1
|
Knutie SA, Bahouth R, Bertone MA, Webb C, Mehta M, Nahom M, Barta RM, Ghai S, Love AC, Horan S, Soldo A, Cochrane E, Bartholomew J, Cowan E, Bjerke H, Balenger SL, Butler MW, Cornell A, Kennedy AC, Rolland V, Schultz EM, Stanback M, Taff CC, Albery GF. Understanding spatiotemporal effects of food supplementation on host-parasite interactions using community-based science. J Anim Ecol 2024. [PMID: 39049456 DOI: 10.1111/1365-2656.14155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 07/11/2024] [Indexed: 07/27/2024]
Abstract
Supplemental feeding can increase the overall health of animals but also can have variable effects on how animals defend themselves against parasites. However, the spatiotemporal effects of food supplementation on host-parasite interactions remain poorly understood, likely because large-scale, coordinated efforts to investigate them are difficult. Here, we introduce the Nest Parasite Community Science Project, which is a community-based science project that coordinates studies with bird nest box 'stewards' from the public and scientific community. This project was established to understand broad ecological patterns between hosts and their parasites. The goal of this study was to determine the effect of food supplementation on eastern bluebirds (Sialia sialis) and their nest parasite community across the geographic range of the bluebirds from 2018 to 2021. We received 674 nests from 69 stewards in 26 states in the eastern United States. Nest box stewards reported whether or not they provided mealworms or suet near nesting bluebirds, then they followed the nesting success of the birds (number of eggs laid and hatched, proportion that hatched, number and proportion of nestlings that successfully fledged). We then identified and quantified parasites in the nests. Overall, we found that food supplementation increased fledging success. The most common nest parasite taxon was the parasitic blow fly (Protocalliphora sialia), but a few nests contained fleas (Ceratophyllus idius, C. gallinae and Orchopeas leucopus) and mites (Dermanyssus spp. and Ornithonyssus spp.). Blow flies were primarily found at northern latitudes, where food supplementation affected blow fly prevalence. However, the direction of this effect varied substantially in direction and magnitude across years. More stewards fed bluebirds at southern latitudes than at northern latitudes, which contradicts the findings of other community-based science projects. Overall, food supplementation of birds was associated with increased host fitness but did not appear to play a consistent role in defence against these parasites across all years. Our study demonstrates the importance of coordinated studies across years and locations to understand the effects of environmental heterogeneity, including human-based food supplementation, on host-parasite dynamics.
Collapse
Affiliation(s)
- Sarah A Knutie
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
- Institute for Systems Genomics, University of Connecticut, Storrs, Connecticut, USA
| | - Rachel Bahouth
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Matthew A Bertone
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, North Carolina, USA
| | - Caroline Webb
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Mahima Mehta
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Mia Nahom
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Rachael M Barta
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Sharan Ghai
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Ashley C Love
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Sydney Horan
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Alexandria Soldo
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Elizabeth Cochrane
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Jenna Bartholomew
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Emily Cowan
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Heather Bjerke
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Susan L Balenger
- Department of Biology, University of Mississippi, Oxford, Mississippi, USA
| | - Michael W Butler
- Department of Biology, Lafayette College, Easton, Pennsylvania, USA
| | - Allison Cornell
- Department of Biology, Penn State Altoona, Altoona, Pennsylvania, USA
| | - Ashley C Kennedy
- Mosquito Control Section, Delaware Division of Fish and Wildlife, Newark, Delaware, USA
| | - Virginie Rolland
- Department of Biology, Arkansas State University, Jonesboro, Arkansas, USA
| | | | - Mark Stanback
- Department of Biology, Davidson College, Davidson, North Carolina, USA
| | - Conor C Taff
- Lab of Ornithology and Department of Ecology & Evolutionary Biology, Cornell University, Ithaca, New York, USA
| | - Gregory F Albery
- Department of Biology, Georgetown University, Washington, District of Columbia, USA
| |
Collapse
|
2
|
Lamberson AM, Smith JA. Supplementary feeding of birds during the winter influences measures of avian community structure in yards in a subtropical city. PLoS One 2024; 19:e0302007. [PMID: 38776305 PMCID: PMC11111068 DOI: 10.1371/journal.pone.0302007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 03/26/2024] [Indexed: 05/24/2024] Open
Abstract
Supplementary feeding, the intentional provision of food to wild birds is a common activity in developed nations during the winter. The energy inputs represented by supplementary feeding are vast, and thus it is likely an important mechanism shaping bird communities in urban areas. However, research in this regard has mainly occurred in temperate and non-urban settings. Moreover, few studies have been informed by supplementary feeding habits of local community members limiting their inference. We evaluated the effects of two commonly provided wild bird foods on the abundance and species diversity of birds in yards over two winters in San Antonio, Texas, United States, a city located in a subtropical region. We used a reversed Before-After-Control-Impact experimental design in which yards were randomly allocated either mixed seed, Nyjer, or no food (control) between November 2019 and March 2020 (Year One). Between November 2020 and March 2021 (Year Two) supplementary food was not provided in any yards. Point counts conducted during both years of the study revealed that overall bird abundance was consistent between years in control yards and yards provided with Nyjer. In contrast, overall bird abundance was statistically significantly higher when supplementary food was present in mixed seed yards, driven by an increase in granivorous and omnivorous species. In contrast, supplementary feeding had no statistically significant effect on the abundance of insectivorous species or on species diversity, although species diversity tended to be higher in the presence of mixed seed. Our study demonstrates that wild bird food commonly provided by community members influences measures of avian community structure during the winter in urban yards in a subtropical city. However, these results depend on the type of bird food provided. Our results provide insight into the processes underlying the effects of urbanization on bird communities, and thus have implications for the management of urban birds more broadly.
Collapse
Affiliation(s)
- Amanda M. Lamberson
- Department of Integrative Biology, The University of Texas at San Antonio, San Antonio, Texas, United States of America
| | - Jennifer A. Smith
- Department of Integrative Biology, The University of Texas at San Antonio, San Antonio, Texas, United States of America
| |
Collapse
|
3
|
Patel K, Stapleton GS, Trevejo RT, Tellier WT, Higa J, Adams JK, Hernandez SM, Sanchez S, Nemeth NM, Debess EE, Rogers KH, Mete A, Watson KD, Foss L, Low MSF, Gollarza L, Nichols M. Human Salmonellosis Outbreak Linked to Salmonella Typhimurium Epidemic in Wild Songbirds, United States, 2020-2021. Emerg Infect Dis 2023; 29:2298-2306. [PMID: 37877570 PMCID: PMC10617330 DOI: 10.3201/eid2911.230332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2023] Open
Abstract
Salmonella infection causes epidemic death in wild songbirds, with potential to spread to humans. In February 2021, public health officials in Oregon and Washington, USA, isolated a strain of Salmonella enterica serovar Typhimurium from humans and a wild songbird. Investigation by public health partners ultimately identified 30 illnesses in 12 states linked to an epidemic of Salmonella Typhimurium in songbirds. We report a multistate outbreak of human salmonellosis associated with songbirds, resulting from direct handling of sick and dead birds or indirect contact with contaminated birdfeeders. Companion animals might have contributed to the spread of Salmonella between songbirds and patients; the outbreak strain was detected in 1 ill dog, and a cat became ill after contact with a wild bird. This outbreak highlights a One Health issue where actions like regular cleaning of birdfeeders might reduce the health risk to wildlife, companion animals, and humans.
Collapse
|
4
|
Doremus J, Li L, Jones D. Covid-related surge in global wild bird feeding: Implications for biodiversity and human-nature interaction. PLoS One 2023; 18:e0287116. [PMID: 37531331 PMCID: PMC10395953 DOI: 10.1371/journal.pone.0287116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 05/30/2023] [Indexed: 08/04/2023] Open
Abstract
The global extent of supplementary bird feeding is unknown but has consequences for bird conservation and human well-being. Using a measure of search intensity for words related to bird feeding from Google, we document a surge of interest in bird feeding that occurred around the world after Covid-19 led to lockdowns where people stayed home: 115 countries saw an increase in bird feeding search interest. We test whether the existence of interest in bird feeding is associated with greater species richness of bird species, our proxy for biodiversity, and find the relationship is highly significant. Covid-19 lockdowns may have persistent influences on global bird populations and humans' connection to nature.
Collapse
Affiliation(s)
- Jacqueline Doremus
- Economics Department, California Polytechnic State University, San Luis Obispo, California, United States of America
| | - Liqing Li
- Department of Agricultural Economics, Texas A&M University College Station, College Station, Texas, United States of America
| | - Darryl Jones
- Centre for Planetary Health & Food Security and School of Environment & Science, Griffith University, Gold Coast, Australia
| |
Collapse
|
5
|
Watson H, Nilsson JÅ, Nilsson JF. Thermoregulatory costs of the innate immune response are modulated by winter food availability in a small passerine. J Anim Ecol 2023; 92:1065-1074. [PMID: 37032462 DOI: 10.1111/1365-2656.13914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 02/28/2023] [Indexed: 04/11/2023]
Abstract
In winter, a challenge to the immune system could pose a major energetic trade-off for small endotherms, whereby increasing body temperature (Tb ; i.e. eliciting fever) may be beneficial to fight off invading pathogens yet incur a cost for vital energy-saving mechanisms. Having previously shown that the availability and acquisition of energy, through manipulation of food predictability, influences the depth of rest-phase hypothermia in a wild bird in winter, we expected that the nocturnal thermoregulatory component of the acute-phase immune response would also be modulated by food availability. By manipulating winter food availability in the wild for great tits Parus major, we created an area offering a "predictable" and constant supply of food at feeding stations, while an unmanipulated area was subject to naturally "unpredictable" food. Birds were subject to an immune challenge shortly after dusk, and the thermoregulatory response was quantified via continuous recording of nocturnal Tb , using subcutaneous thermo-sensitive transponders. In response to immune challenge, all birds increased Tb above the level maintained prior to immune challenge (i.e. baseline). However, birds experiencing a naturally unpredictable food supply elevated Tb more than birds subject to predictable food resources, during the period of expected peak response and for the duration of the night. Furthermore, "unpredictable-food" females took longer to return to their baseline Tb . Assuming baseline nocturnal Tb reflects an individual's optimum, based on their available energy budget, the metabolic cost of eliciting an acute-phase response for "unpredictable-food" birds was more than double that of "predictable-food" birds. The absence of differences in absolute Tb during the peak response could support the idea of an optimal Tb for immune system activation. Alternatively, "predictable-food" birds could have acquired tolerance to endotoxin as a result of using feeding stations, thus affording them reduced costs associated with a smaller Tb increase. These findings shed new light on the trade-offs associated with food acquisition, thermoregulation and immune function in small-bodied endotherms. This knowledge is of increasing importance, given the predicted elevated pathogen risks associated with changes in climate and anthropogenic activities.
Collapse
Affiliation(s)
- Hannah Watson
- Evolutionary Ecology, Lund University, Lund, SE-223 62, Sweden
| | - Jan-Åke Nilsson
- Evolutionary Ecology, Lund University, Lund, SE-223 62, Sweden
| | - Johan F Nilsson
- Evolutionary Ecology, Lund University, Lund, SE-223 62, Sweden
| |
Collapse
|
6
|
Wanelik KM, Begon M, Bradley JE, Friberg IM, Jackson JA, Taylor CH, Paterson S. Effects of an IgE receptor polymorphism acting on immunity, susceptibility to infection, and reproduction in a wild rodent. eLife 2023; 12:e77666. [PMID: 36645701 PMCID: PMC9842384 DOI: 10.7554/elife.77666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 12/22/2022] [Indexed: 01/17/2023] Open
Abstract
The genotype of an individual is an important predictor of their immune function, and subsequently, their ability to control or avoid infection and ultimately contribute offspring to the next generation. However, the same genotype, subjected to different intrinsic and/or extrinsic environments, can also result in different phenotypic outcomes, which can be missed in controlled laboratory studies. Natural wildlife populations, which capture both genotypic and environmental variability, provide an opportunity to more fully understand the phenotypic expression of genetic variation. We identified a synonymous polymorphism in the high-affinity Immunoglobulin E (IgE) receptor (GC and non-GC haplotypes) that has sex-dependent effects on immune gene expression, susceptibility to infection, and reproductive success of individuals in a natural population of field voles (Microtus agrestis). We found that the effect of the GC haplotype on the expression of immune genes differed between sexes. Regardless of sex, both pro-inflammatory and anti-inflammatory genes were more highly relatively expressed in individuals with the GC haplotype than individuals without the haplotype. However, males with the GC haplotype showed a stronger signal for pro-inflammatory genes, while females showed a stronger signal for anti-inflammatory genes. Furthermore, we found an effect of the GC haplotype on the probability of infection with a common microparasite, Babesia microti, in females - with females carrying the GC haplotype being more likely to be infected. Finally, we found an effect of the GC haplotype on reproductive success in males - with males carrying the GC haplotype having a lower reproductive success. This is a rare example of a polymorphism whose consequences we are able to follow across immunity, infection, and reproduction for both males and females in a natural population.
Collapse
Affiliation(s)
- Klara M Wanelik
- Institute of Infection, Veterinary and Ecological Sciences, University of LiverpoolLiverpoolUnited Kingdom
| | - Mike Begon
- Institute of Infection, Veterinary and Ecological Sciences, University of LiverpoolLiverpoolUnited Kingdom
| | - Janette E Bradley
- School of Life Sciences, University of NottinghamNottinghamUnited Kingdom
| | - Ida M Friberg
- School of Environment and Life Sciences, University of SalfordSalfordUnited Kingdom
| | - Joseph A Jackson
- School of Environment and Life Sciences, University of SalfordSalfordUnited Kingdom
| | | | - Steve Paterson
- Institute of Infection, Veterinary and Ecological Sciences, University of LiverpoolLiverpoolUnited Kingdom
| |
Collapse
|
7
|
Briggs CW, Dudus KA, Ely TE, Kwasnoski LA, Downs CJ. Hemolytic parasites affect survival in migrating red-tailed hawks. CONSERVATION PHYSIOLOGY 2022; 10:coac075. [PMID: 36570735 PMCID: PMC9773370 DOI: 10.1093/conphys/coac075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 10/18/2022] [Accepted: 11/18/2022] [Indexed: 06/17/2023]
Abstract
Migrating birds face a myriad of hazards, including higher exposure to parasites and numerous competing energy demands. It follows that migration may act as a selective filter and limit population growth. Understanding how individual-level physiological condition and disease status scale up to population dynamics through differential survival of individuals is necessary to identify threats and management interventions for migratory populations, many of which face increasing conservation challenges. However, linking individual physiological condition, parasite infection status and survival can be difficult. We examined the relationship among two measures of physiological condition [scaled-mass index and heterophil/leukocyte (H/L) ratio], hematozoa (i.e. hemoparasites) presence and abundance, and constitutive immunity in 353 autumn migrating red-tailed hawks (Buteo jamaicensis calurus) from 2004 to 2018. Hematazoa (i.e. Haemoproteus and Leucocytozoon) were in the blood smears from 139 red-tailed hawks (39.4%). H/L ratio decreased with scaled-mass index. Adults had a significantly higher H/L ratio than juveniles. Our two measures of immune defences, hemolytic-complement activity and bacteria-killing ability, were highly positively correlated. Our most notable finding was a negative relationship between Haemoproteus parasitemia and survival (i.e. documented individual mortality), indicating that haemosporidian parasites influence survival during a challenging life stage. The effect of haemosporidian parasites on individuals is often debated, and we provide evidence that parasitemia can affect individual survival. In contrast, we did not find evidence of trade-offs between survival and immune defences.
Collapse
Affiliation(s)
- Christopher W Briggs
- Golden Gate Raptor Observatory, Golden Gate National Parks Conservancy, Sausalito, CA 94965, USA
- Department of Biology, Colgate University, Hamilton, NY 13346, USA
- Department of Environmental Biology, State University of New York College of Environmental Science and Forestry, Syracuse, NY 13210, USA
| | - Kris A Dudus
- Golden Gate Raptor Observatory, Golden Gate National Parks Conservancy, Sausalito, CA 94965, USA
- National Park Service, Gulf Breeze, FL 32563, USA
| | - Teresa E Ely
- Golden Gate Raptor Observatory, Golden Gate National Parks Conservancy, Sausalito, CA 94965, USA
| | | | - Cynthia J Downs
- Corresponding author: Department of Environmental Biology, State University of New York College of Environmental Science and Forestry, Syracuse, NY 13210, USA.
| |
Collapse
|
8
|
Galvin AN, Pandit PS, English SG, Quock RC, Bandivadekar RR, Colwell RR, Robinson BW, Ernest HB, Brown MH, Sehgal RNM, Tell LA. Evaluation of minimally invasive sampling methods for detecting Avipoxvirus: Hummingbirds as a case example. Front Vet Sci 2022; 9:924854. [PMID: 36090172 PMCID: PMC9450938 DOI: 10.3389/fvets.2022.924854] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 07/18/2022] [Indexed: 11/13/2022] Open
Abstract
Avian pox is a common avian virus that in its cutaneous form can cause characteristic lesions on a bird's dermal surfaces. Detection of avian pox in free-ranging birds historically relied on observations of visual lesions and/or histopathology, both which can underestimate avian pox prevalence. We compared traditional visual observation methods for avian pox with molecular methods that utilize minimally invasive samples (blood, toenail clipping, feathers, and dermal swabs) in an ecologically important group of birds, hummingbirds. Specifically, avian pox prevalence in several species of hummingbirds were examined across multiple locations using three different methods: (1) visual inspection of hummingbirds for pox-like lesions from a long-term banding data set, (2) qPCR assay of samples from hummingbird carcasses from wildlife rehabilitation centers, and (3) qPCR assay of samples from live-caught hummingbirds. A stark difference in prevalences among these three methods was identified, with an avian pox prevalence of 1.5% from banding data, 20.4% from hummingbird carcasses, and 32.5% from live-caught hummingbirds in California. This difference in detection rates underlines the necessity of a molecular method to survey for avian pox, and this study establishes one such method that could be applied to other wild bird species. Across all three methods, Anna's hummingbirds harbored significantly higher avian pox prevalence than other species examined, as did males compared with females and birds caught in Southern California compared with Northern California. After hatch-year hummingbirds also harbored higher avian pox prevalences than hatch-year hummingbirds in the California banding data set and the carcass data set. This is the first study to estimate the prevalence of avian pox in hummingbirds and address the ecology of this hummingbird-specific strain of avian pox virus, providing vital information to inform future studies on this charismatic and ecologically important group of birds.
Collapse
Affiliation(s)
- Aoife N. Galvin
- Department of Biology, San Francisco State University, San Francisco, CA, United States
| | - Pranav S. Pandit
- EpiCenter for Disease Dynamics, One Health Insititute, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| | - Simon G. English
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| | - Rachel C. Quock
- Department of Biology, San Francisco State University, San Francisco, CA, United States
| | - Ruta R. Bandivadekar
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| | - Rita R. Colwell
- Hummingbird Monitoring Network, Patagonia, AZ, United States
| | | | - Holly B. Ernest
- Wildlife Genomics and Disease Ecology Laboratory, Department of Veterinary Sciences, University of Wyoming, Laramie, WY, United States
| | - Mollie H. Brown
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| | - Ravinder N. M. Sehgal
- Department of Biology, San Francisco State University, San Francisco, CA, United States
- *Correspondence: Ravinder N. M. Sehgal
| | - Lisa A. Tell
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
- Lisa A. Tell
| |
Collapse
|
9
|
Population density mediates induced immune response, but not physiological condition in a well-adapted urban bird. Sci Rep 2022; 12:9150. [PMID: 35650222 PMCID: PMC9160275 DOI: 10.1038/s41598-022-12910-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 05/18/2022] [Indexed: 11/30/2022] Open
Abstract
Thriving under high population density is considered a major feature of urban exploiter species. Nevertheless, population density appears to be a surprisingly overlooked factor in urban ecology studies. High population numbers observed in urban species might promote pathogen transmission and negatively affect health or condition, thus requiring investments in immunocompetence. The feral pigeon Columba livia domestica is an example of a successful city-dweller, found in great abundance in large cities across the globe. We investigated the effects of population density on induced immune response (phytohaemagglutinin skin test) and body condition (blood haemoglobin concentration and size-corrected body mass) in 120 feral pigeons, captured along population density gradient in Łódź (central Poland). We found that stronger immune response was associated with higher population density, but was not related to physiological condition and physiological stress (heterophil/lymphocyte ratio). Moreover, condition indices were not associated with population density. However, since pigeon population density was highly correlated with the level of habitat urbanization, we cannot exclude that any density-dependent effects may be mediated by habitat variation. Our results indicate that urban environment, via population density, might exert different selective pressures on immunocompetence and body condition in this successful urban exploiter.
Collapse
|
10
|
Affiliation(s)
- Amy R. Sweeny
- Institute of Evolutionary Biology University of Edinburgh Edinburgh Scotland
| | - Gregory F. Albery
- Department of Biology Georgetown University Washington DC USA
- Wissenschaftskolleg zu Berlin Berlin Germany
| |
Collapse
|
11
|
Corra J, Sullivan SMP. Temperature and land use influence tree swallow individual health. CONSERVATION PHYSIOLOGY 2021; 9:coab084. [PMID: 34712488 PMCID: PMC8546433 DOI: 10.1093/conphys/coab084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 08/30/2021] [Accepted: 10/06/2021] [Indexed: 06/13/2023]
Abstract
Aerial insectivorous bird populations have declined precipitously in both North America and Europe. We assessed the effects of insect prey availability, climate and shifts in water quality associated with urbanization on haematocrit, haemoglobin concentration and heterophil-lymphocyte (H/L) ratios among ~13-day-old tree swallow (Tachycineta bicolor) nestlings in the Columbus, Ohio area. Higher mean temperature and increased frequency of extreme heat days during the early breeding period (May-June) were linked to reduced nestling physiological condition as evidenced by lower concentrations of haemoglobin and haematocrit, potentially due to increased heat stress, shifts in insect prey availability or altered parental provisioning efforts. Urbanization and the size and density of emergent aquatic insects were associated with elevated physiological stress, whereas higher mean temperatures and terrestrial insect size were related to lower stress as measured by H/L ratios. Overall, these findings highlight the complex environmental conditions driving nestling health, which may be indicative of post-fledging survival and, consequently, population growth. Our results underscore the need for conservation approaches that adequately address the interrelated effects of changes in climate, land use and food resources on aerial insectivorous birds.
Collapse
Affiliation(s)
- Joseph Corra
- Office of Research and Development, U.S. Environmental Protection Agency, 26 Martin Luther King Dr., Cincinnati, OH 45268, USA
| | - S Mažeika P Sullivan
- School of Environment and Natural Resources, The Ohio State University, 125 Heffner Bldg 352 W. Dodridge St., Columbus, OH 43202, USA
| |
Collapse
|
12
|
Names GR, Schultz EM, Hahn TP, Hunt KE, Angelier F, Ribout C, Klasing KC. Variation in immunity and health in response to introduced avian malaria in an endemic Hawaiian songbird. Anim Conserv 2021. [DOI: 10.1111/acv.12744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- G. R. Names
- Animal Behavior Graduate Group University of California Davis Davis CA USA
- Department of Neurobiology Physiology and Behavior University of California Davis Davis CA USA
| | - E. M. Schultz
- Department of Biology Wittenberg University Springfield OH USA
| | - T. P. Hahn
- Department of Neurobiology Physiology and Behavior University of California Davis Davis CA USA
| | - K. E. Hunt
- Smithsonian‐Mason School of Conservation & Department of Biology George Mason University Front Royal VA USA
| | - F. Angelier
- Centre d'Etudes Biologiques de Chizé, CNRS‐La Rochelle Université, UMR7372 Villiers en Bois France
| | - C. Ribout
- Centre d'Etudes Biologiques de Chizé, CNRS‐La Rochelle Université, UMR7372 Villiers en Bois France
| | - K. C. Klasing
- Department of Animal Science University of California Davis Davis CA USA
| |
Collapse
|
13
|
Hockenhull J, Squibb K, Cameron A. How Has the COVID-19 Pandemic Affected the Way We Access and Interact with the Countryside and the Animals within It? Animals (Basel) 2021; 11:ani11082281. [PMID: 34438739 PMCID: PMC8388493 DOI: 10.3390/ani11082281] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 07/27/2021] [Accepted: 07/30/2021] [Indexed: 12/05/2022] Open
Abstract
Simple Summary In March 2020, the UK entered its first mandatory lockdown to reduce the spread of COVID-19. The restrictions associated with the lockdown led to changes in human behaviour, particularly in relation to exercise and accessing the outdoors. This study used an online survey of UK residents to explore these changes and to understand how people interacted with the natural world while they were outside, including interactions with wildlife and domestic animals. There was an increase in how often respondents went for walks outside during lockdown, compared to pre-lockdown levels, and this increase lasted beyond the end of the first lockdown. Interacting with animals was a common feature of walks. This most commonly involved watching wildlife or domestic animals, such as livestock or horses, but sometimes also involved physically interacting with them and/or feeding them which may have implications for their welfare, for example, if inappropriate food is provided. There is also a risk of humans transferring disease between the animals they have contact with or zoonotic disease transmission between the humans and animals. While is it positive that people are interacting with the natural world, it is important that this does not compromise animal wellbeing. Abstract There is growing evidence that the changes in human behaviour resulting from the COVID-19 pandemic have had positive and negative impacts on the natural world. This study used an online survey to explore how the first UK lockdown affected human exercising behaviour, with particular focus on the role of wild and domestic animals. The survey was completed by 308 respondents. There was a significant increase in the frequency that respondents went for walks outdoors during lockdown, in comparison to pre-lockdown levels (p ≤ 0.001), and this was sustained (albeit to a lesser extent) once lockdown ended (p = 0.005). Engaging with the natural world was an important feature of walks outside for 81% of respondents. A small proportion of respondents reported physically interacting with the animals they encountered and/or feeding them, which may have implications for their welfare. The findings suggest that those who value animal encounters during their time outside always seek these interactions, while those who do not, did not tend to change this behaviour following lockdown. Should the changes in human exercising behaviour be sustained, it is important to balance the benefits of walking outdoors for human health and wellbeing with the health and welfare of the animals they encounter.
Collapse
Affiliation(s)
- Jo Hockenhull
- Animal Welfare and Behaviour Group, Bristol Veterinary School, University of Bristol, Langford, Bristol BS40 5DU, UK;
- Correspondence:
| | | | - Amelia Cameron
- Animal Welfare and Behaviour Group, Bristol Veterinary School, University of Bristol, Langford, Bristol BS40 5DU, UK;
- School of Veterinary Medicine and Science, University of Nottingham, Loughborough LE12 5RD, UK
| |
Collapse
|
14
|
Erastova DA, Galbraith JA, Cain KE, van Heezik Y, Filion A, Stanley MC. Sugar water feeding practices are associated with bird species composition in urban backyards. JOURNAL OF URBAN ECOLOGY 2021. [DOI: 10.1093/jue/juab018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Feeding backyard birds with sugar water is increasingly popular in urban areas, but it has poorly understood effects on bird assemblages. In New Zealand, ca. 20% of households engaged in feeding wild birds use sugar water, often in an attempt to attract native, nectarivorous birds. Developing best practices for sugar water feeding could be a powerful tool for attracting these species in urban areas. However, it is currently unclear whether these feeders actually support native species, and, if so, which feeding practices are most effective in increasing visitation. We surveyed New Zealanders who provide sugar water to birds about their feeding practices via an online questionnaire. The aim of our research was to understand existing practices and their effect on attracting native species, as well as the motivations and social factors behind urban sugar water bird feeding. Our results show that this practice is popular throughout the country with the majority of households successful in attracting native nectarivorous species to their gardens. Sugar water feeder type had the largest effect on reported species richness at feeders in comparison to other factors (e.g. sugar concentration). Feeders specifically designed for nectarivorous birds, namely the Tui Nectar Feeder™, are more successful at attracting natives in comparison to other commonly used feeder types. Thus, individual householder decisions around feeder use can have important consequences for bird species composition in urban gardens. Future research is needed to understand the consequences of sugar water feeding for bird communities and individual bird health.
Collapse
Affiliation(s)
- Daria A Erastova
- School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Josie A Galbraith
- Auckland War Memorial Museum, The Auckland Domain, Parnell, Auckland 1010, New Zealand
| | - Kristal E Cain
- School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Yolanda van Heezik
- Department of Zoology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Antoine Filion
- Department of Zoology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Margaret C Stanley
- School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| |
Collapse
|
15
|
Lack of Evidence That Bird Feeders Are a Source of Salmonellosis during Winter in Poland. Animals (Basel) 2021; 11:ani11061831. [PMID: 34205243 PMCID: PMC8234643 DOI: 10.3390/ani11061831] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 06/17/2021] [Accepted: 06/18/2021] [Indexed: 11/17/2022] Open
Abstract
Bird feeders are known to be a transfer site for many important bird pathogens, such as zoonotic Salmonella spp., known to be widespread among wild birds in Poland. The aim of the study was to investigate (1) whether feeders can be a source of Salmonella spp., (2) whether the risk is the same for feeders located in cities and rural areas and (3) whether there is a different level of contamination with Salmonella spp. between old and new feeders. Data were collected in the period 12 January-28 February 2018 in four cities in Poland and nearby rural areas. In total, 204 feeders were sampled. The samples from feeders were taken after a 2-week period of feeding birds. Material for analysis consisted of the remains of food and feces. We did not find the presence of Salmonella spp. in any of the tested samples collected from bird feeders. Therefore, the estimated value of the 95% confidence interval for the binary data was 0.000-0.018. Reasons for the isolation of Salmonella spp. from feeders not being successful lie in the low intensity of bacterial shedding by infected wild birds and low survival of bacteria in the environment in bird feces-which are still not well studied.
Collapse
|
16
|
Schaper L, Hutton P, McGraw KJ. Bird-feeder cleaning lowers disease severity in rural but not urban birds. Sci Rep 2021; 11:12835. [PMID: 34145310 PMCID: PMC8213693 DOI: 10.1038/s41598-021-92117-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 12/02/2020] [Indexed: 11/24/2022] Open
Abstract
Animals inhabiting urban areas often experience elevated disease threats, putatively due to factors such as increased population density and horizontal transmission or decreased immunity (e.g. due to nutrition, pollution, stress). However, for animals that take advantage of human food subsidies, like feeder-visiting birds, an additional mechanism may include exposure to contaminated feeders as fomites. There are some published associations between bird feeder presence/density and avian disease, but to date no experimental study has tested the hypothesis that feeder contamination can directly impact disease status of visiting birds, especially in relation to the population of origin (i.e. urban v. rural, where feeder use/densities naturally vary dramatically). Here we used a field, feeder-cleaning experimental design to show that rural, but not urban, house finches (Haemorhous mexicanus) showed increased infection from a common coccidian endoparasite (Isospora spp.) when feeders were left uncleaned and that daily cleaning (with diluted bleach solution) over a 5-week period successfully decreased parasite burden. Moreover, this pattern in rural finches was true for males but not females. These experimental results reveal habitat- and sex-specific harmful effects of bird feeder use (i.e. when uncleaned in rural areas). Our study is the first to directly indicate to humans who maintain feeders for granivorous birds that routine cleaning can be critical for ensuring the health and viability of visiting avian species.
Collapse
Affiliation(s)
- Laren Schaper
- Barrett The Honors College, Arizona State University, Tempe, AZ, 85287, USA.,School of Life Sciences, Arizona State University, Tempe, AZ, 85287, USA
| | - Pierce Hutton
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287, USA
| | - Kevin J McGraw
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287, USA.
| |
Collapse
|
17
|
Abstract
Avian pox is a widespread infection in birds caused by genus Avipoxvirus pathogens. It is a noteworthy, potentially lethal disease to wild and domestic hosts. It can produce two different conditions: cutaneous pox, and diphtheritic pox. Here, we carry out an exhaustive review of all cases of avian pox reported from wild birds to analyze the effect and distribution in different avian species. Avian poxvirus strains have been detected in at least 374 wild bird species, a 60% increase on a 1999 review on avian pox hosts. We also analyze epizootic cases and if this disease contributes to wild bird population declines. We frequently observe very high prevalence in wild birds in remote island groups, e.g., Hawaii, Galapagos, etc., representing a major risk for the conservation of their unique endemic avifauna. However, the difference in prevalence between islands and continents is not significant given the few available studies. Morbidity and mortality can also be very high in captive birds, due to high population densities. However, despite the importance of the disease, the current detection rate of new Avipoxvirus strains suggests that diversity is incomplete for this group, and more research is needed to clarify its real extent, particularly in wild birds.
Collapse
|
18
|
Stephens CRA, McAmmond BM, Van Hamme JD, Otter KA, Reudink MW, Bottos EM. Analysis of bacterial communities associated with Mountain Chickadees ( Poecile gambeli) across urban and rural habitats. Can J Microbiol 2021; 67:572-583. [PMID: 33656947 DOI: 10.1139/cjm-2020-0320] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Host-associated microbial communities play important roles in wildlife health, but these dynamics can be influenced by environmental factors. Urbanization has numerous effects on wildlife; however, the degree to which wildlife-associated bacterial communities and potential bacterial pathogens vary across urban-rural/native habitat gradients remains largely unknown. We used 16S rRNA gene amplicon sequencing to examine bacterial communities found on Mountain Chickadee (Poecile gambeli) feathers and nests in urban and rural habitats. The feathers and nests in urban and rural sites had similar abundances of major bacterial phyla and dominant genera with pathogenic members. However, richness of bacterial communities and potential pathogens on birds were higher in urban habitats, and potential pathogens accounted for some of the differences in bacterial occurrence between urban and rural environments. We predicted habitat using potential pathogen occurrence with a 90% success rate for feather bacteria, and a 72.2% success rate for nest bacteria, suggesting an influence of urban environments on the presence of potential pathogens. We additionally observed similarities in bacterial communities between nests and their occupants, suggesting bacterial transmission between them. These findings improve our understanding of the bacterial communities associated with urban wildlife and suggest that urbanization impacts the composition of wildlife-associated bacterial communities.
Collapse
Affiliation(s)
- Colton R A Stephens
- Department of Biological Sciences, Thompson Rivers University, 805 TRU Way, Kamloops, BC V2C 0C8, Canada
| | - Breanne M McAmmond
- Department of Biological Sciences, Thompson Rivers University, 805 TRU Way, Kamloops, BC V2C 0C8, Canada
| | - Jonathan D Van Hamme
- Department of Biological Sciences, Thompson Rivers University, 805 TRU Way, Kamloops, BC V2C 0C8, Canada
| | - Ken A Otter
- Natural Resources and Environmental Studies, University of Northern British Columbia, 3333 University Way, Prince George, BC V2N 4Z9, Canada
| | - Matthew W Reudink
- Department of Biological Sciences, Thompson Rivers University, 805 TRU Way, Kamloops, BC V2C 0C8, Canada
| | - Eric M Bottos
- Department of Biological Sciences, Thompson Rivers University, 805 TRU Way, Kamloops, BC V2C 0C8, Canada
| |
Collapse
|
19
|
Carmona M, Aymí R, Navarro J. Importance of predictable anthropogenic food subsidies for an opportunistic gull inhabiting urban ecosystems. EUR J WILDLIFE RES 2021. [DOI: 10.1007/s10344-020-01446-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
|
20
|
Aberle M, Langwig K, Adelman J, Hawley D. Effects of bird feeder density on the foraging behaviors of a backyard songbird (the House Finch, Haemorhous mexicanus) subject to seasonal disease outbreaks. CAN J ZOOL 2020. [DOI: 10.1139/cjz-2019-0282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Provisioning of wildlife, such as backyard bird feeding, can alter animal behavior and ecology in diverse ways. For species that are highly dependent on supplemental resources, it is critical to understand how variation in the degree of provisioning, as occurs naturally across backyards, alters wildlife behavior and ecology in ways potentially relevant to disease spread. We experimentally manipulated feeder density at suburban sites and tracked local abundance, foraging behaviors, body mass, and movement in House Finches (Haemorhous mexicanus (P.L. Statius Müller, 1776)), the primary host of a pathogen commonly spread at feeders. Sites with high feeder density harbored higher local House Finch abundance, and birds at these sites had longer feeding bouts and total time on feeders relative to sites with low feeder density. House Finches at high-density feeder sites had lower residual body mass despite greater apparent feeder access. Finally, birds first recorded at low-density feeder sites were more likely to move to neighboring high-density feeder sites than vice versa. Because local abundance and time spent on feeders have both been linked with disease risk in this species, the effects of heterogeneity in bird feeder density on these traits may have important consequences for disease dynamics in this system and more broadly.
Collapse
Affiliation(s)
- M.A. Aberle
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - K.E. Langwig
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - J.S. Adelman
- Department of Biological Sciences, University of Memphis, Memphis, TN 38152, USA
| | - D.M. Hawley
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| |
Collapse
|
21
|
Cummings CR, Hernandez SM, Murray M, Ellison T, Adams HC, Cooper RE, Curry S, Navara KJ. Effects of an anthropogenic diet on indicators of physiological challenge and immunity of white ibis nestlings raised in captivity. Ecol Evol 2020; 10:8416-8428. [PMID: 32788990 PMCID: PMC7417218 DOI: 10.1002/ece3.6548] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 05/12/2020] [Accepted: 06/02/2020] [Indexed: 12/01/2022] Open
Abstract
When wildlife forage and/or live in urban habitats, they often experience a shift in resource availability and dietary quality. Some species even use human handouts, such as bread, as well as human refuse, as a large part of their new diets; yet the influences of this nutritional shift on health and survival remain unclear. American white ibises are increasingly being seen in urban areas in Florida; they collect handouts, such as bread and other food items, from humans in parks, and are also found foraging on anthropogenic sources in trash heaps. We hypothesized that the consumption of these new anthropogenic food sources may trigger increases in indicators of physiological challenge and dampen immune responses. We tested this experimentally by raising 20 white ibis nestlings in captivity, and exposing 10 to a simulated anthropogenic diet (including the addition of white bread and a reduction in seafood content) while maintaining 10 on a diet similar to what ibises consume in more natural environments. We then tested two indicators of physiological challenge (corticosterone and heat shock protein 70), assessed innate immunity in these birds via bactericidal assays and an in vitro carbon clearance assay, and adaptive immunity using a phytohemagglutinin skin test. The anthropogenic diet depressed the development of the ability to kill Salmonella paratyphi in culture. Our results suggest that consuming an anthropogenic diet may be detrimental in terms of the ability to battle a pathogenic bacterial species, but there was little effect on indicators of physiological challenge and other immunological measures.
Collapse
Affiliation(s)
| | - Sonia M. Hernandez
- Warnell School of Forestry and Natural ResourcesThe University of GeorgiaAthensGAUSA
| | - Maureen Murray
- Department of Poultry ScienceThe University of GeorgiaAthensGAUSA
- Warnell School of Forestry and Natural ResourcesThe University of GeorgiaAthensGAUSA
| | - Taylor Ellison
- Department of Poultry ScienceThe University of GeorgiaAthensGAUSA
- Warnell School of Forestry and Natural ResourcesThe University of GeorgiaAthensGAUSA
| | - Henry C. Adams
- Department of Poultry ScienceThe University of GeorgiaAthensGAUSA
- Warnell School of Forestry and Natural ResourcesThe University of GeorgiaAthensGAUSA
| | - Robert E. Cooper
- Department of Poultry ScienceThe University of GeorgiaAthensGAUSA
- Warnell School of Forestry and Natural ResourcesThe University of GeorgiaAthensGAUSA
| | - Shannon Curry
- Warnell School of Forestry and Natural ResourcesThe University of GeorgiaAthensGAUSA
| | | |
Collapse
|
22
|
Hammond RL. Bird Feeders Increase Connection to Nature in Parents But Not in Their Children. ECOPSYCHOLOGY 2020. [DOI: 10.1089/eco.2019.0036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Ruby L. Hammond
- Biological Sciences Department, Northern Arizona University, Flagstaff, Arizona
| |
Collapse
|
23
|
Knutie SA. Food supplementation affects gut microbiota and immunological resistance to parasites in a wild bird species. J Appl Ecol 2020. [DOI: 10.1111/1365-2664.13567] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Sarah A. Knutie
- Department of Ecology and Evolutionary Biology University of Connecticut Storrs CT USA
- Institute for Systems Genomics University of Connecticut Storrs CT USA
| |
Collapse
|
24
|
Becker DJ, Albery GF, Kessler MK, Lunn TJ, Falvo CA, Czirják GÁ, Martin LB, Plowright RK. Macroimmunology: The drivers and consequences of spatial patterns in wildlife immune defence. J Anim Ecol 2020; 89:972-995. [PMID: 31856309 DOI: 10.1111/1365-2656.13166] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 11/06/2019] [Indexed: 01/26/2023]
Abstract
The prevalence and intensity of parasites in wild hosts varies across space and is a key determinant of infection risk in humans, domestic animals and threatened wildlife. Because the immune system serves as the primary barrier to infection, replication and transmission following exposure, we here consider the environmental drivers of immunity. Spatial variation in parasite pressure, abiotic and biotic conditions, and anthropogenic factors can all shape immunity across spatial scales. Identifying the most important spatial drivers of immunity could help pre-empt infectious disease risks, especially in the context of how large-scale factors such as urbanization affect defence by changing environmental conditions. We provide a synthesis of how to apply macroecological approaches to the study of ecoimmunology (i.e. macroimmunology). We first review spatial factors that could generate spatial variation in defence, highlighting the need for large-scale studies that can differentiate competing environmental predictors of immunity and detailing contexts where this approach might be favoured over small-scale experimental studies. We next conduct a systematic review of the literature to assess the frequency of spatial studies and to classify them according to taxa, immune measures, spatial replication and extent, and statistical methods. We review 210 ecoimmunology studies sampling multiple host populations. We show that whereas spatial approaches are relatively common, spatial replication is generally low and unlikely to provide sufficient environmental variation or power to differentiate competing spatial hypotheses. We also highlight statistical biases in macroimmunology, in that few studies characterize and account for spatial dependence statistically, potentially affecting inferences for the relationships between environmental conditions and immune defence. We use these findings to describe tools from geostatistics and spatial modelling that can improve inference about the associations between environmental and immunological variation. In particular, we emphasize exploratory tools that can guide spatial sampling and highlight the need for greater use of mixed-effects models that account for spatial variability while also allowing researchers to account for both individual- and habitat-level covariates. We finally discuss future research priorities for macroimmunology, including focusing on latitudinal gradients, range expansions and urbanization as being especially amenable to large-scale spatial approaches. Methodologically, we highlight critical opportunities posed by assessing spatial variation in host tolerance, using metagenomics to quantify spatial variation in parasite pressure, coupling large-scale field studies with small-scale field experiments and longitudinal approaches, and applying statistical tools from macroecology and meta-analysis to identify generalizable spatial patterns. Such work will facilitate scaling ecoimmunology from individual- to habitat-level insights about the drivers of immune defence and help predict where environmental change may most alter infectious disease risk.
Collapse
Affiliation(s)
- Daniel J Becker
- Department of Biology, Indiana University, Bloomington, IN, USA.,Center for the Ecology of Infectious Disease, University of Georgia, Athens, GA, USA
| | - Gregory F Albery
- Department of Biology, Georgetown University, Washington, DC, USA
| | | | - Tamika J Lunn
- Environmental Futures Research Institute, Griffith University, Nathan, Queensland, Australia
| | - Caylee A Falvo
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | - Gábor Á Czirják
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Lynn B Martin
- Department of Global and Planetary Health, University of South Florida, Tampa, FL, USA
| | - Raina K Plowright
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| |
Collapse
|
25
|
Bailes EJ, Bagi J, Coltman J, Fountain MT, Wilfert L, Brown MJF. Host density drives viral, but not trypanosome, transmission in a key pollinator. Proc Biol Sci 2020; 287:20191969. [PMID: 31910787 PMCID: PMC7003466 DOI: 10.1098/rspb.2019.1969] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Supplemental feeding of wildlife populations can locally increase the density of individuals, which may in turn impact disease dynamics. Flower strips are a widely used intervention in intensive agricultural systems to nutritionally support pollinators such as bees. Using a controlled experimental semi-field design, we asked how density impacts transmission of a virus and a trypanosome parasite in bumblebees. We manipulated bumblebee density by using different numbers of colonies within the same area of floral resource. In high-density compartments, slow bee paralysis virus was transmitted more quickly, resulting in higher prevalence and level of infection in bumblebee hosts. By contrast, there was no impact of density on the transmission of the trypanosome Crithidia bombi, which may reflect the ease with which this parasite is transmitted. These results suggest that agri-environment schemes such as flower strips, which are known to enhance the nutrition and survival of bumblebees, may also have negative impacts on pollinators through enhanced disease transmission. Future studies should assess how changing the design of these schemes could minimize disease transmission and thus maximise their health benefits to wild pollinators.
Collapse
Affiliation(s)
- Emily J Bailes
- Department of Biological Sciences, Royal Holloway University of London, Bourne Building, Egham TW20 0EX, UK.,Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Sheffield S10 2TN, UK
| | - Judit Bagi
- Department of Biological Sciences, Royal Holloway University of London, Bourne Building, Egham TW20 0EX, UK.,Ear Institute, University College London, 332 Gray's Inn Road, London WC1X 8EE, UK
| | - Jake Coltman
- Expedia Group, Angel Building, 407 St John Street, London EC1V 4AD, UK
| | | | - Lena Wilfert
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, 89069 Ulm, Germany
| | - Mark J F Brown
- Department of Biological Sciences, Royal Holloway University of London, Bourne Building, Egham TW20 0EX, UK
| |
Collapse
|
26
|
Paton GD, Shoffner AV, Wilson AM, Gagné SA. The traits that predict the magnitude and spatial scale of forest bird responses to urbanization intensity. PLoS One 2019; 14:e0220120. [PMID: 31344134 PMCID: PMC6657869 DOI: 10.1371/journal.pone.0220120] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 07/09/2019] [Indexed: 11/19/2022] Open
Abstract
As humans continue moving to urban areas, there is a growing need to understand the effects of urban intensification on native wildlife populations. Forest species in remnant habitat are particularly vulnerable to urban intensification, but the mechanisms behind these effects are poorly understood. An understanding of how species traits, as proxies for mechanisms, mediate the effects of urban intensification on forest species can help fill this knowledge gap. Using a large point count dataset from the Second Pennsylvania Breeding Bird Atlas, we tested for the effects of species traits on the magnitude and spatial scale of the responses of 58 forest bird species to urbanization intensity in landscapes surrounding count locations. Average urbanization intensity effect size across species was -0.36 ± 0.49 (SE) and average scale of effect of urbanization intensity was 4.87 ± 5.95 km. Resident forest bird species that are granivorous or frugivorous, cavity-nesting, and have larger clutch sizes and more fledglings per clutch had more positive associations with increasing urbanization intensity in landscapes. In addition, the effect of urbanization intensity on forest birds manifested most strongly at larger spatial scales for granivorous, frugivorous, or omnivorous species that are cavity-nesting, have larger clutch sizes and longer wingspans, and flock in larger numbers. To our knowledge, the present study represents the first direct tests of the effects of species traits on both the magnitude and spatial scale of the effect of urbanization on forest birds, as well as the first evidence that migratory status, clutch size, wingspan, and fledglings per clutch are important determinants of the responses of forest birds to urbanization. We discuss the possible mechanisms underlying our results and their implications for forest bird conservation in urbanizing landscapes.
Collapse
Affiliation(s)
- Grant D. Paton
- Department of Geography and Earth Sciences, The University of North Carolina at Charlotte, Charlotte, North Carolina, United States of America
- * E-mail:
| | - Alexandra V. Shoffner
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, United States of America
| | - Andrew M. Wilson
- Environmental Studies Department, Gettysburg College, Gettysburg, Pennsylvania, United States of America
| | - Sara A. Gagné
- Department of Geography and Earth Sciences, The University of North Carolina at Charlotte, Charlotte, North Carolina, United States of America
| |
Collapse
|
27
|
Graham JL, Needham KB, Bertucci EM, Pearson AA, Bauer CM, Greives TJ. Onset of Daily Activity in a Female Songbird Is Related to Peak-Induced Estradiol Levels. Integr Comp Biol 2019; 59:1059-1067. [DOI: 10.1093/icb/icz112] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Research in captive birds and mammals has demonstrated that circadian (i.e., daily) behavioral rhythms are altered in response to increases in sex-steroid hormones. Recently, we and others have demonstrated a high degree of individual repeatability in peak (gonadotropin-releasing hormone [GnRH]-induced sex) steroid levels, and we have found that these GnRH-induced levels are highly correlated with their daily (night-time) endogenous peak. Whether or not individual variation in organization and activity of the reproductive endocrine axis is related to daily timing in wild animals is not well known. To begin to explore these possible links, we tested the hypothesis that maximal levels of the sex steroid hormone estradiol (E2) and onset of daily activity are related in a female songbird, the dark-eyed junco (Junco hyemalis). We found that females with higher levels of GnRH-induced E2 departed from their nest in the morning significantly earlier than females with lower stimulated levels. We did not observe a relationship between testosterone and this measure of onset of activity. Our findings suggest an interaction between an individual’s reproductive endocrine axis and the circadian system and variation observed in an individuals’ daily activity onset. We suggest future studies examine the relationship between maximal sex-steroid hormones and timing of daily activity onset.
Collapse
Affiliation(s)
- Jessica L Graham
- Ecologie Comportementale, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National De La Recherche Scientifique (CNRS), 1919 Route de Mende, 34293 Montpellier 5, France
- Department of Biological Sciences, North Dakota State University, 201 Stevens Hall, 1340 Bolley Drive, Fargo, ND 58108-6050, USA
| | - Katie B Needham
- Department of Biological Sciences, North Dakota State University, 201 Stevens Hall, 1340 Bolley Drive, Fargo, ND 58108-6050, USA
| | - Emily M Bertucci
- School of Ecology, University of Georgia, 140 E Green Street, Athens, GA 30602-2202, USA
| | - Alexis A Pearson
- Department of Biological Sciences, North Dakota State University, 201 Stevens Hall, 1340 Bolley Drive, Fargo, ND 58108-6050, USA
| | - Carolyn M Bauer
- Department of Biology, Adelphi University, 1 South Ave, Garden City, NY 11530, USA
| | - Timothy J Greives
- Department of Biological Sciences, North Dakota State University, 201 Stevens Hall, 1340 Bolley Drive, Fargo, ND 58108-6050, USA
| |
Collapse
|
28
|
Vennum CR, Downs CJ, Hayes JP, Houston I, Collopy MW, Woodbridge B, Briggs CW. Early Life Conditions and Immune Defense in Nestling Swainson's Hawks. Physiol Biochem Zool 2019; 92:419-429. [PMID: 31180801 DOI: 10.1086/704364] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The quality of perinatal conditions directly influences the physical and immunological development of nestlings, yet it is inherently variable across space and time. Long-term breeding data for a population of Swainson's hawks (Buteo swainsoni) in northern California show a continuum of territory occupancy and productivity values of individual territories and nests. Here we explore effects of variation among territories on immune system development. We hypothesize that nestlings benefitting from favorable conditions will invest in stronger immune systems, a trait with long-term benefits. We used two immunological assays, a bactericidal assay and a hemolytic-complement activity assay, with leukocyte differentials (heterophil∶lymphocyte ratio) to evaluate the constitutive innate immune system. We examined whether early brood-rearing conditions (i.e., number of siblings, hatch date, endoparasite prevalence) were associated with immunological development. Linear mixed-effects models indicated a positive relationship between extended territory occupancy history-an index of habitat quality-and nestling immune function during years with poorer reproduction. There was no association during an exceptionally good reproductive year. Hence, at least under some circumstances, nestling environments or territory characteristics may affect immune function of nestlings. Our study contributes to the growing body of evidence highlighting the importance of facultative allocation to immune traits using long-term demographic data of a top avian predator.
Collapse
|
29
|
The composition of British bird communities is associated with long-term garden bird feeding. Nat Commun 2019; 10:2088. [PMID: 31113960 PMCID: PMC6529538 DOI: 10.1038/s41467-019-10111-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 04/18/2019] [Indexed: 11/17/2022] Open
Abstract
There is a multi-billion dollar global industry dedicated to feeding wild birds in residential gardens. This extraordinary boost to food resources is almost certainly reshaping entire bird communities, yet the large-scale, long-term impacts on community ecology remain unknown. Here we reveal a 40-year transformation of the bird communities using garden bird feeders in Britain, and provide evidence to suggest how this may have contributed to national-scale population changes. We find that increases in bird diversity at feeders are associated with increasing community evenness, as species previously rarely observed in gardens have increasingly exploited the growing variety of foods on offer over time. Urban areas of Britain are consequently nurturing growing populations of feeder-using bird species, while the populations of species that do not use feeders remain unchanged. Our findings illustrate the on-going, gross impact people can have on bird community structure across large spatial scales. Garden bird feeding is a prolific human activity that provides a reliable foraging opportunity to wild birds. Here the authors use a 40-year data set to show that large-scale restructuring of garden bird communities and growth in urban bird populations can be linked to changing feeding practices.
Collapse
|
30
|
Dayer AA, Rosenblatt C, Bonter DN, Faulkner H, Hall RJ, Hochachka WM, Phillips TB, Hawley DM. Observations at backyard bird feeders influence the emotions and actions of people that feed birds. PEOPLE AND NATURE 2019. [DOI: 10.1002/pan3.17] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Ashley A. Dayer
- Department of Fish and Wildlife Conservation Virginia Tech Blacksburg Virginia
| | - Connor Rosenblatt
- Department of Fish and Wildlife Conservation Virginia Tech Blacksburg Virginia
| | | | | | - Richard J. Hall
- Odum School of Ecology and Department of Infectious Diseases College of Veterinary Medicine University of Georgia Athens Georgia
| | | | | | - Dana M. Hawley
- Department of Biological Sciences Virginia Tech Blacksburg Virginia
| |
Collapse
|
31
|
Lajoie JL, Ganio LM, Rivers JW. Individual variation and seasonality drive bird feeder use during winter in a Mediterranean climate. Ecol Evol 2019; 9:2535-2549. [PMID: 30891198 PMCID: PMC6405926 DOI: 10.1002/ece3.4902] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 12/06/2018] [Accepted: 12/14/2018] [Indexed: 12/23/2022] Open
Abstract
Purposeful provisioning of food to wild animals is a widespread and growing activity that has the potential to impact populations and communities. Nevertheless, studies assessing use of recreational feeders by free-living birds during winter are surprisingly rare and largely limited to regions with continental climates characterized by freezing temperatures and snow cover. In contrast, there is little information available regarding bird use of feeders within warmer climates during winter, despite widespread recreational feeding in these areas. In this study, we quantified visitation patterns to bird feeders in a Mediterranean climate to evaluate the relationship between feeder use and several environmental variables known to influence supplemental feeder use in continental climates. We established a network of bird feeders in Corvallis, Oregon, USA, that were filled with black oil sunflower (Helianthus annuus) seeds and equipped with radio frequency identification (RFID) data loggers that recorded >315,000 visits by 70 individual Black-capped Chickadees (Poecile atricapillus) across a 5-month period (October 2016-March 2017). We found extensive variation in feeder use, with individuals averaging 1-406 feeder visits/day and using 1-9 of the 21 feeders that were available; individual variability was largely consistent during the course of our study. At the population level, we found that feeder use decreased from the start of our study, and this decline continued through the period when foraging was most limited by daylight, including the winter solstice. In contrast to theoretical predictions and empirical work in continental climates, we found that weather variables did not drive feeder use and that feeder visits peaked at mid-day and gradually decreased until sunset. Our study indicates that individual-level differences combined with seasonality to drive feeder use patterns, and we conclude that use of supplemental feeders during winter in Mediterranean climates appears to differ notably from feeder use in continental climates.
Collapse
Affiliation(s)
- Janel L. Lajoie
- Department of Forest Ecosystems and SocietyOregon State UniversityCorvallisOregon
| | - Lisa M. Ganio
- Department of Forest Ecosystems and SocietyOregon State UniversityCorvallisOregon
| | - James W. Rivers
- Department of Forest Ecosystems and SocietyOregon State UniversityCorvallisOregon
| |
Collapse
|
32
|
Strandin T, Babayan SA, Forbes KM. Reviewing the effects of food provisioning on wildlife immunity. Philos Trans R Soc Lond B Biol Sci 2019. [PMID: 29531143 DOI: 10.1098/rstb.2017.0088] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
While urban expansion increasingly encroaches on natural habitats, many wildlife species capitalize on anthropogenic food resources, which have the potential to both positively and negatively influence their responses to infection. Here we examine how food availability and key nutrients have been reported to shape innate and adaptive immunity in wildlife by drawing from field-based studies, as well as captive and food restriction studies with wildlife species. Examples of food provisioning and key nutrients enhancing immune function were seen across the three study type distinctions, as were cases of trace metals and pharmaceuticals impairing the immunity of wildlife species. More generally, food provisioning in field studies tended to increase innate and adaptive responses to certain immune challenges, whereas patterns were less clear in captive studies. Mild food restriction often enhanced, whereas severe food restriction frequently impaired immunity. However, to enable stronger conclusions we stress a need for further research, especially field studies, and highlight the importance of integrating nutritional manipulation, immune challenge, and functional outcomes. Despite current gaps in research on this topic, modern high throughput molecular approaches are increasingly feasible for wildlife studies and offer great opportunities to better understand human influences on wildlife health.This article is part of the theme issue 'Anthropogenic resource subsidies and host-parasite dynamics in wildlife'.
Collapse
Affiliation(s)
- Tomas Strandin
- Department of Virology, University of Helsinki, Helsinki 00290, Finland
| | - Simon A Babayan
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, UK.,The Moredun Research Institute, Pentlands Science Park, Penicuik, Midlothian EH26 0PZ, UK
| | - Kristian M Forbes
- Department of Virology, University of Helsinki, Helsinki 00290, Finland .,Center for Infectious Disease Dynamics and Department of Biology, The Pennsylvania State University, University Park, PA 16082, USA
| |
Collapse
|
33
|
Lawson B, Robinson RA, Toms MP, Risely K, MacDonald S, Cunningham AA. Health hazards to wild birds and risk factors associated with anthropogenic food provisioning. Philos Trans R Soc Lond B Biol Sci 2019. [PMID: 29531146 PMCID: PMC5882997 DOI: 10.1098/rstb.2017.0091] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Provision of supplementary food for wild birds at garden feeding stations is a common, large-scale and year-round practice in multiple countries including Great Britain (GB). While these additional dietary resources can benefit wildlife, there is a concomitant risk of disease transmission, particularly when birds repeatedly congregate in the same place at high densities and through interactions of species that would not normally associate in close proximity. Citizen science schemes recording garden birds are popular and can integrate disease surveillance with population monitoring, offering a unique opportunity to explore inter-relationships between supplementary feeding, disease epidemiology and population dynamics. Here, we present findings from a national surveillance programme in GB and note the dynamism of endemic and emerging diseases over a 25-year period, focusing on protozoal (finch trichomonosis), viral (Paridae pox) and bacterial (passerine salmonellosis) diseases with contrasting modes of transmission. We also examine the occurrence of mycotoxin contamination of food residues in bird feeders, which present both a direct and indirect (though immunosuppression) risk to wild bird health. Our results inform evidence-based mitigation strategies to minimize anthropogenically mediated health hazards, while maintaining the benefits of providing supplementary food for wild birds.This article is part of the theme issue 'Anthropogenic resource subsidies and host-parasite dynamics in wildlife'.
Collapse
Affiliation(s)
- Becki Lawson
- Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK
| | - Robert A Robinson
- British Trust for Ornithology, The Nunnery, Thetford, Norfolk IP24 2PU, UK
| | - Mike P Toms
- British Trust for Ornithology, The Nunnery, Thetford, Norfolk IP24 2PU, UK
| | - Kate Risely
- British Trust for Ornithology, The Nunnery, Thetford, Norfolk IP24 2PU, UK
| | - Susan MacDonald
- Fera Science Ltd, National Agri-Food Innovation Campus, Sand Hutton, York YO41 1LZ, UK
| | - Andrew A Cunningham
- Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK
| |
Collapse
|
34
|
Altizer S, Becker DJ, Epstein JH, Forbes KM, Gillespie TR, Hall RJ, Hawley DM, Hernandez SM, Martin LB, Plowright RK, Satterfield DA, Streicker DG. Food for contagion: synthesis and future directions for studying host-parasite responses to resource shifts in anthropogenic environments. Philos Trans R Soc Lond B Biol Sci 2019. [PMID: 29531154 DOI: 10.1098/rstb.2017.0102] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Human-provided resource subsidies for wildlife are diverse, common and have profound consequences for wildlife-pathogen interactions, as demonstrated by papers in this themed issue spanning empirical, theoretical and management perspectives from a range of study systems. Contributions cut across scales of organization, from the within-host dynamics of immune function, to population-level impacts on parasite transmission, to landscape- and regional-scale patterns of infection. In this concluding paper, we identify common threads and key findings from author contributions, including the consequences of resource subsidies for (i) host immunity; (ii) animal aggregation and contact rates; (iii) host movement and landscape-level infection patterns; and (iv) interspecific contacts and cross-species transmission. Exciting avenues for future work include studies that integrate mechanistic modelling and empirical approaches to better explore cross-scale processes, and experimental manipulations of food resources to quantify host and pathogen responses. Work is also needed to examine evolutionary responses to provisioning, and ask how diet-altered changes to the host microbiome influence infection processes. Given the massive public health and conservation implications of anthropogenic resource shifts, we end by underscoring the need for practical recommendations to manage supplemental feeding practices, limit human-wildlife conflicts over shared food resources and reduce cross-species transmission risks, including to humans.This article is part of the theme issue 'Anthropogenic resource subsidies and host-parasite dynamics in wildlife'.
Collapse
Affiliation(s)
- Sonia Altizer
- Odum School of Ecology, College of Veterinary Medicine, University of Georgia, Athens, GA, USA .,Center for the Ecology of Infectious Disease, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Daniel J Becker
- Odum School of Ecology, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.,Center for the Ecology of Infectious Disease, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.,Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | | | - Kristian M Forbes
- Department of Virology, University of Helsinki, Helsinki, Finland.,Department of Biology, The Pennsylvania State University, University Park, PA, USA.,Center for Infectious Disease Dynamics, The Pennsylvania State University, University Park, PA, USA
| | - Thomas R Gillespie
- Department of Environmental Sciences and Program in Population Biology, Ecology and Evolution, Rollins School of Public Health, Emory University, Atlanta, GA, USA.,Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Richard J Hall
- Odum School of Ecology, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.,Center for the Ecology of Infectious Disease, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.,Department of Infectious Disease, College of Veterinary Medicine, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Dana M Hawley
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, USA
| | - Sonia M Hernandez
- Warnell School of Forestry and Natural Resources, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.,Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Lynn B Martin
- Department of Integrative Biology, University of South Florida, Tampa, FL, USA
| | - Raina K Plowright
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | - Dara A Satterfield
- Migratory Bird Center, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC 20008, USA
| | - Daniel G Streicker
- Odum School of Ecology, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.,Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, UK.,MRC-University of Glasgow Centre for Virus Research, Glasgow G61 1QH, UK
| |
Collapse
|
35
|
Moyers SC, Adelman JS, Farine DR, Thomason CA, Hawley DM. Feeder density enhances house finch disease transmission in experimental epidemics. Philos Trans R Soc Lond B Biol Sci 2019. [PMID: 29531145 DOI: 10.1098/rstb.2017.0090] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Anthropogenic food provisioning of wildlife can alter the frequency of contacts among hosts and between hosts and environmental sources of pathogens. Despite the popularity of garden bird feeding, few studies have addressed how feeders influence host contact rates and disease dynamics. We experimentally manipulated feeder density in replicate aviaries containing captive, pathogen-naive, groups of house finches (Haemorhous mexicanus) and continuously tracked behaviours at feeders using radio-frequency identification devices. We then inoculated one bird per group with Mycoplasma gallisepticum (Mg), a common bacterial pathogen for which feeders are fomites of transmission, and assessed effects of feeder density on house finch behaviour and pathogen transmission. We found that pathogen transmission was significantly higher in groups with the highest density of bird feeders, despite a significantly lower rate of intraspecific aggressive interactions relative to the low feeder density groups. Conversely, among naive group members that never showed signs of disease, we saw significantly higher concentrations of Mg-specific antibodies in low feeder density groups, suggesting that birds in low feeder density treatments had exposure to subclinical doses of Mg. We discuss ways in which the density of garden bird feeders could play an important role in mediating the intensity of Mg epidemics.This article is part of the theme issue 'Anthropogenic resource subsidies and host-parasite dynamics in wildlife'.
Collapse
Affiliation(s)
- Sahnzi C Moyers
- Department of Biological Sciences, Virginia Tech, Derring Hall Room 2125, 1405 Perry Street, Blacksburg, VA 24061-0406, USA
| | - James S Adelman
- Department of Biological Sciences, Virginia Tech, Derring Hall Room 2125, 1405 Perry Street, Blacksburg, VA 24061-0406, USA.,Natural Resource Ecology and Management Department, Iowa State University, Ames, IA 50011, USA
| | - Damien R Farine
- Edward Grey Institute of Field Ornithology, Department of Zoology, University of Oxford, Oxford OX1 3PS, UK.,Department of Collective Behaviour, Max Planck Institute for Ornithology, Konstanz 78464, Germany.,Chair of Biodiversity and Collective Behaviour, Department of Biology, University of Konstanz, Konstanz 78464, Germany
| | - Courtney A Thomason
- Department of Biological Sciences, Virginia Tech, Derring Hall Room 2125, 1405 Perry Street, Blacksburg, VA 24061-0406, USA
| | - Dana M Hawley
- Department of Biological Sciences, Virginia Tech, Derring Hall Room 2125, 1405 Perry Street, Blacksburg, VA 24061-0406, USA
| |
Collapse
|
36
|
Becker DJ, Hall RJ, Forbes KM, Plowright RK, Altizer S. Anthropogenic resource subsidies and host-parasite dynamics in wildlife. Philos Trans R Soc Lond B Biol Sci 2019. [PMID: 29531141 DOI: 10.1098/rstb.2017.0086] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Affiliation(s)
- Daniel J Becker
- Odum School of Ecology, College of Veterinary Medicine, University of Georgia, Athens, GA, USA .,Center for the Ecology of Infectious Disease, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.,Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | - Richard J Hall
- Odum School of Ecology, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.,Center for the Ecology of Infectious Disease, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.,Department of Infectious Disease, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Kristian M Forbes
- Department of Virology, University of Helsinki, Helsinki, Finland.,Center for Infectious Disease Dynamics, Pennsylvania State University, University Park, PA, USA.,Department of Biology, Pennsylvania State University, University Park, PA, USA
| | - Raina K Plowright
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | - Sonia Altizer
- Odum School of Ecology, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.,Center for the Ecology of Infectious Disease, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| |
Collapse
|
37
|
Murray MH, Kidd AD, Curry SE, Hepinstall-Cymerman J, Yabsley MJ, Adams HC, Ellison T, Welch CN, Hernandez SM. From wetland specialist to hand-fed generalist: shifts in diet and condition with provisioning for a recently urbanized wading bird. Philos Trans R Soc Lond B Biol Sci 2019. [PMID: 29531152 DOI: 10.1098/rstb.2017.0100] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Many wildlife species shift their diets to use novel resources in urban areas. The consequences of these shifts are not well known, and consumption of reliable-but low quality-anthropogenic food may present important trade-offs for wildlife health. This may be especially true for carnivorous species such as the American white ibis (Eudocimus albus), a nomadic wading bird which has been increasingly observed in urban parks in South Florida, USA. We tested the effects of anthropogenic provisioning on consumer nutrition (i.e. dietary protein), body condition and ectoparasite burdens along an urban gradient using stable isotope analysis, scaled mass index values and GPS transmitter data. Ibises that assimilated more provisioned food were captured at more urban sites, used more urban habitat, had lower mass-length residuals, lower ectoparasite scores, assimilated less δ15N and had smaller dietary isotopic ellipses. Our results suggest that ibises in urban areas are heavily provisioned with anthropogenic food, which appears to offer a trade-off by providing low-quality, but easily accessible, calories that may not support high mass but may increase time available for anti-parasite behaviours such as preening. Understanding such trade-offs is important for investigating the effects of provisioning on infection risk and the conservation of wildlife in human-modified habitats.This article is part of the theme issue 'Anthropogenic resource subsidies and host-parasite dynamics in wildlife'.
Collapse
Affiliation(s)
- Maureen H Murray
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA .,Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Anjelika D Kidd
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA.,Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Shannon E Curry
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA.,Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | | | - Michael J Yabsley
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA.,Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Henry C Adams
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA.,Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Taylor Ellison
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA.,Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Catharine N Welch
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA.,Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Sonia M Hernandez
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA.,Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| |
Collapse
|
38
|
Needham KB, Bergeon Burns C, Graham JL, Bauer CM, Kittilson JD, Ketterson ED, Hahn T, Greives TJ. Changes in processes downstream of the hypothalamus are associated with seasonal follicle development in a songbird, the dark-eyed junco (Junco hyemalis). Gen Comp Endocrinol 2019; 270:103-112. [PMID: 30339809 DOI: 10.1016/j.ygcen.2018.10.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 10/04/2018] [Accepted: 10/15/2018] [Indexed: 02/07/2023]
Abstract
Mechanisms related to seasonal reproductive timing in vertebrates have received far more study in males than in females, despite the fact that female timing decisions dictate when rearing of offspring will occur. Production and release of gonadotropin-releasing hormone (GnRH) by the hypothalamus stimulates the pituitary to secrete gonadotropins, initiating the beginning stages of gonadal recrudescence and production of the sex steroids, testosterone and estradiol, which are necessary to prime the liver for secretion of yolk precursors in breeding female birds. While stimulation by the hypothalamus can occur during the pre-breeding period, egg development itself is likely regulated downstream of the hypothalamus. We used GnRH challenges to examine variation in breeding-stage-specific patterns of pituitary and ovarian responsiveness in free-living female dark-eyed juncos (Junco hyemalis) and also examined the ovary and liver for variation in mRNA expression of candidate genes. Baseline LH levels increased during the transition from pre-breeding to egg-development, however no significant difference was observed in post-GnRH injection levels for LH or sex steroids (testosterone and estradiol). Interestingly, a stage by time-point interaction was observed, with post-GnRH LH levels increasing over baseline during the pre-breeding stage, but not during the egg-development stage. We observed a decrease in liver mRNA expression of estradiol receptor-alpha, and glucocorticoid and mineralocorticoid receptors and a decrease in glucocorticoid receptor expression levels in the ovary. A decline in FSH receptor expression across stages was also observed in the ovary. Combined, our data suggest seasonal variation in female's sensitivity to signals of HPG activity and energetic or stress signals. These data provide additional insight into the physiological mechanisms regulating onset of clutch initiation.
Collapse
Affiliation(s)
- Katie B Needham
- Department of Biological Sciences, North Dakota State University, Fargo, ND, USA; Environmental and Conservation Sciences Program, North Dakota State University, Fargo, ND, USA
| | | | - Jessica L Graham
- Department of Biological Sciences, North Dakota State University, Fargo, ND, USA; Environmental and Conservation Sciences Program, North Dakota State University, Fargo, ND, USA
| | - Carolyn M Bauer
- Department of Biological Sciences, North Dakota State University, Fargo, ND, USA; Department of Biology, Adelphi University, Garden City, NY, USA
| | - Jeffrey D Kittilson
- Department of Biological Sciences, North Dakota State University, Fargo, ND, USA
| | | | - Thomas Hahn
- College of Biological Sciences, UC Davis, Davis, CA, USA
| | - Timothy J Greives
- Department of Biological Sciences, North Dakota State University, Fargo, ND, USA; Environmental and Conservation Sciences Program, North Dakota State University, Fargo, ND, USA
| |
Collapse
|
39
|
Tollington S, Ewen JG, Newton J, McGill RAR, Smith D, Henshaw A, Fogell DJ, Tatayah V, Greenwood A, Jones CG, Groombridge JJ. Individual consumption of supplemental food as a predictor of reproductive performance and viral infection intensity. J Appl Ecol 2018. [DOI: 10.1111/1365-2664.13303] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Simon Tollington
- Durrell Institute of Conservation and EcologySchool of Anthropology and ConservationUniversity of Kent Canterbury UK
- North of England Zoological Society Chester UK
| | - John G. Ewen
- Institute of ZoologyZoological Society of London London UK
| | - Jason Newton
- NERC Life Sciences Mass Spectrometry FacilitySUERC East Kilbride UK
| | | | - Donal Smith
- Institute of ZoologyZoological Society of London London UK
- School of Environment and Life SciencesUniversity of Salford Salford UK
| | | | - Deborah J. Fogell
- Durrell Institute of Conservation and EcologySchool of Anthropology and ConservationUniversity of Kent Canterbury UK
- Institute of ZoologyZoological Society of London London UK
| | | | | | - Carl G. Jones
- School of Environment and Life SciencesUniversity of Salford Salford UK
- Durrell Wildlife Conservation Trust Jersey UK
| | - Jim J. Groombridge
- Durrell Institute of Conservation and EcologySchool of Anthropology and ConservationUniversity of Kent Canterbury UK
| |
Collapse
|
40
|
The relative effects of forest amount, forest configuration, and urban matrix quality on forest breeding birds. Sci Rep 2018; 8:17140. [PMID: 30459396 PMCID: PMC6244229 DOI: 10.1038/s41598-018-35276-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 10/25/2018] [Indexed: 11/17/2022] Open
Abstract
Urbanization modifies landscape structure in three major ways that impact avian diversity in remnant habitat: habitat amount is reduced and habitat configuration and matrix quality are altered. The relative effects of these three components of landscape structure are relatively well-studied in agricultural landscapes, but little is known about the relative effect of urban matrix quality. We addressed this gap by investigating the relative effects of forest amount, forest configuration, and matrix quality, indicated by degree of urbanization and agriculture amount, on the diversity of three guilds of forest birds using data from 13,763 point counts from Pennsylvania, USA. Forest amount had the largest independent effect on forest bird diversity, followed by matrix quality, then forest configuration. In particular, urbanization had strong negative effects on the relative abundance and species evenness of all forest birds and the relative abundance of forest generalist birds. To our knowledge, these are the first results of the effect of urban matrix quality on forest bird relative abundance and species evenness independent of forest amount and forest configuration. Our results imply that conservation practitioners in human-modified landscapes prioritize maximizing forest amount, then reducing the effects of disturbances originating in the matrix, and then preserving large, spatially-dispersed forest patches to most effectively conserve forest birds.
Collapse
|
41
|
Spatio-temporal dynamics and aetiology of proliferative leg skin lesions in wild British finches. Sci Rep 2018; 8:14670. [PMID: 30305642 PMCID: PMC6180014 DOI: 10.1038/s41598-018-32255-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 08/31/2018] [Indexed: 11/21/2022] Open
Abstract
Proliferative leg skin lesions have been described in wild finches in Europe although there have been no large-scale studies of their aetiology or epizootiology to date. Firstly, disease surveillance, utilising public reporting of observations of live wild finches was conducted in Great Britain (GB) and showed proliferative leg skin lesions in chaffinches (Fringilla coelebs) to be widespread. Seasonal variation was observed, with a peak during the winter months. Secondly, pathological investigations were performed on a sample of 39 chaffinches, four bullfinches (Pyrrhula pyrrhula), one greenfinch (Chloris chloris) and one goldfinch (Carduelis carduelis) with proliferative leg skin lesions and detected Cnemidocoptes sp. mites in 91% (41/45) of affected finches and from all species examined. Fringilla coelebs papillomavirus (FcPV1) PCR was positive in 74% (23/31) of birds tested: a 394 base pair sequence was derived from 20 of these birds, from all examined species, with 100% identity to reference genomes. Both mites and FcPV1 DNA were detected in 71% (20/28) of birds tested for both pathogens. Histopathological examination of lesions did not discriminate the relative importance of mite or FcPV1 infection as their cause. Development of techniques to localise FcPV1 within lesions is required to elucidate the pathological significance of FcPV1 DNA detection.
Collapse
|
42
|
Citizen science reveals widespread supplementary feeding of African woolly-necked storks in suburban areas of KwaZulu-Natal, South Africa. Urban Ecosyst 2018. [DOI: 10.1007/s11252-018-0774-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
43
|
Becker DJ, Czirják GÁ, Volokhov DV, Bentz AB, Carrera JE, Camus MS, Navara KJ, Chizhikov VE, Fenton MB, Simmons NB, Recuenco SE, Gilbert AT, Altizer S, Streicker DG. Livestock abundance predicts vampire bat demography, immune profiles and bacterial infection risk. Philos Trans R Soc Lond B Biol Sci 2018; 373:20170089. [PMID: 29531144 PMCID: PMC5882995 DOI: 10.1098/rstb.2017.0089] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/26/2017] [Indexed: 12/14/2022] Open
Abstract
Human activities create novel food resources that can alter wildlife-pathogen interactions. If resources amplify or dampen, pathogen transmission probably depends on both host ecology and pathogen biology, but studies that measure responses to provisioning across both scales are rare. We tested these relationships with a 4-year study of 369 common vampire bats across 10 sites in Peru and Belize that differ in the abundance of livestock, an important anthropogenic food source. We quantified innate and adaptive immunity from bats and assessed infection with two common bacteria. We predicted that abundant livestock could reduce starvation and foraging effort, allowing for greater investments in immunity. Bats from high-livestock sites had higher microbicidal activity and proportions of neutrophils but lower immunoglobulin G and proportions of lymphocytes, suggesting more investment in innate relative to adaptive immunity and either greater chronic stress or pathogen exposure. This relationship was most pronounced in reproductive bats, which were also more common in high-livestock sites, suggesting feedbacks between demographic correlates of provisioning and immunity. Infection with both Bartonella and haemoplasmas were correlated with similar immune profiles, and both pathogens tended to be less prevalent in high-livestock sites, although effects were weaker for haemoplasmas. These differing responses to provisioning might therefore reflect distinct transmission processes. Predicting how provisioning alters host-pathogen interactions requires considering how both within-host processes and transmission modes respond to resource shifts.This article is part of the theme issue 'Anthropogenic resource subsidies and host-parasite dynamics in wildlife'.
Collapse
Affiliation(s)
- Daniel J Becker
- Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
- Center for the Ecology of Infectious Disease, University of Georgia, Athens, GA 30602, USA
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | - Gábor Á Czirják
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Dmitriy V Volokhov
- Center for Biologics Evaluation & Research, U.S. Food & Drug Administration, Rockville, MD, USA
| | - Alexandra B Bentz
- Department of Poultry Science, University of Georgia, Athens, GA, USA
- Department of Biology, Indiana University, Bloomington, IN, USA
| | - Jorge E Carrera
- Facultad de Ciencias, Universidad Nacional de Piura, Piura, Perú
- Programa de Conservación de Murciélagos de Perú, Piura, Perú
| | - Melinda S Camus
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Kristen J Navara
- Department of Poultry Science, University of Georgia, Athens, GA, USA
| | - Vladimir E Chizhikov
- Center for Biologics Evaluation & Research, U.S. Food & Drug Administration, Rockville, MD, USA
| | - M Brock Fenton
- Department of Biology, Western University, London, Ontario, Canada
| | - Nancy B Simmons
- Department of Mammalogy, Division of Vertebrate Zoology, American Museum of Natural History, New York, NY, USA
| | - Sergio E Recuenco
- Department of Preventive Medicine and Public Health, Faculty of Medicine, Universidad Nacional Mayor de San Marcos, Lima, Perú
| | - Amy T Gilbert
- National Wildlife Research Center, United States Department of Agriculture, Fort Collins, CO, USA
| | - Sonia Altizer
- Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
- Center for the Ecology of Infectious Disease, University of Georgia, Athens, GA 30602, USA
| | - Daniel G Streicker
- Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
| |
Collapse
|
44
|
Hwang J, Kim Y, Lee S, Kim N, Chun M, Lee H, Gottdenker N. Anthropogenic food provisioning and immune phenotype: Association among supplemental food, body condition, and immunological parameters in urban environments. Ecol Evol 2018; 8:3037-3046. [PMID: 29531715 PMCID: PMC5838038 DOI: 10.1002/ece3.3814] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 11/06/2017] [Accepted: 12/11/2017] [Indexed: 11/23/2022] Open
Abstract
Direct or indirect supplemental feeding of free-ranging animals occurs worldwide, resulting in significant impacts on population density or altered demographic processes. Another potential impact of increased energy intake from supplemental feeding is altered immunocompetence. As immune system maintenance is energetically costly, there may be trade-offs between immune responses and other energy-demanding physiological processes in individual animals. Although increased availability of food sources through supplemental feeding is expected to increase the overall immunocompetence of animals, empirical data verifying the association between supplemental feeding and different immune parameters are lacking. Understanding the potential influence of supplemental feeding on immune phenotypes is critical, as it may also impact host-pathogen dynamics in free-ranging animals. Using urban stray cats as a study model, we tested for associations between the intensity of supplemental feeding due to cat caretaker activity (CCA); body condition; and immune phenotype (bacterial killing assay (BKA), immunoglobulin G (IgG) concentration, and leukocyte counts). Significantly higher bacterial killing ability was observed in cats from high CCA districts, whereas higher IgG concentration and eosinophil counts were observed in cats from low CCA districts. Other leukocyte counts and body condition indices showed no significant association with CCA. We observed varying patterns of different immune components in relation to supplemental feeding. Out data suggest that supplemental feeding influences immune phenotype, not only by means of energy provisioning, but also by potentially reducing exposure rates to parasite infections through stray cat behavioral changes.
Collapse
Affiliation(s)
- Jusun Hwang
- Department of Veterinary PathologyCollege of Veterinary MedicineUniversity of GeorgiaAthensGAUSA
- College of Veterinary MedicineSeoul National UniversitySeoulKorea
| | - Yongbaek Kim
- College of Veterinary MedicineSeoul National UniversitySeoulKorea
| | - Sang‐Won Lee
- College of Veterinary MedicineKon‐Kuk UniversitySeoulKorea
| | - Na‐Yon Kim
- College of Veterinary MedicineSeoul National UniversitySeoulKorea
| | - Myung‐Sun Chun
- College of Veterinary MedicineSeoul National UniversitySeoulKorea
| | - Hang Lee
- College of Veterinary MedicineSeoul National UniversitySeoulKorea
| | - Nicole Gottdenker
- Department of Veterinary PathologyCollege of Veterinary MedicineUniversity of GeorgiaAthensGAUSA
| |
Collapse
|
45
|
Becker DJ, Streicker DG, Altizer S, Derryberry E. Using host species traits to understand the consequences of resource provisioning for host-parasite interactions. J Anim Ecol 2018; 87:511-525. [PMID: 29023699 PMCID: PMC5836909 DOI: 10.1111/1365-2656.12765] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Accepted: 08/31/2017] [Indexed: 12/17/2022]
Abstract
Supplemental food provided to wildlife by human activities can be more abundant and predictable than natural resources, and subsequent changes in wildlife ecology can have profound impacts on host-parasite interactions. Identifying traits of species associated with increases or decreases in infection outcomes with resource provisioning could improve assessments of wildlife most prone to disease risks in changing environments. We conducted a phylogenetic meta-analysis of 342 host-parasite interactions across 56 wildlife species and three broad taxonomic groups of parasites to identify host-level traits that influence whether provisioning is associated with increases or decreases in infection. We predicted dietary generalists that capitalize on novel food would show greater infection in provisioned habitats owing to population growth and food-borne exposure to contaminants and parasite infectious stages. Similarly, species with fast life histories could experience stronger demographic and immunological benefits from provisioning that affect parasite transmission. We also predicted that wide-ranging and migratory behaviours could increase infection risks with provisioning if concentrated and non-seasonal foods promote dense aggregations that increase exposure to parasites. We found that provisioning increased infection with bacteria, viruses, fungi and protozoa (i.e. microparasites) most for wide-ranging, dietary generalist host species. Effect sizes for ectoparasites were also highest for host species with large home ranges but were instead lowest for dietary generalists. In contrast, the type of provisioning was a stronger correlate of infection outcomes for helminths than host species traits. Our analysis highlights host traits related to movement and feeding behaviour as important determinants of whether species experience greater infection with supplemental feeding. These results could help prioritize monitoring wildlife with particular trait profiles in anthropogenic habitats to reduce infectious disease risks in provisioned populations.
Collapse
Affiliation(s)
- Daniel J. Becker
- Odum School of EcologyUniversity of GeorgiaAthensGAUSA
- Center for the Ecology of Infectious DiseaseUniversity of GeorgiaAthensGAUSA
| | - Daniel G. Streicker
- Odum School of EcologyUniversity of GeorgiaAthensGAUSA
- Institute of Biodiversity, Animal Health and Comparative MedicineUniversity of GlasgowGlasgowUK
- MRC‐University of Glasgow Centre for Virus ResearchGlasgowUK
| | - Sonia Altizer
- Odum School of EcologyUniversity of GeorgiaAthensGAUSA
- Center for the Ecology of Infectious DiseaseUniversity of GeorgiaAthensGAUSA
| | | |
Collapse
|
46
|
Galbraith JA, Jones DN, Beggs JR, Parry K, Stanley MC. Urban Bird Feeders Dominated by a Few Species and Individuals. Front Ecol Evol 2017. [DOI: 10.3389/fevo.2017.00081] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
47
|
MacColl E, Vanesky K, Buck JA, Dudek BM, Eagles-Smith CA, Heath JA, Herring G, Vennum C, Downs CJ. Correlates of immune defenses in golden eagle nestlings. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2017; 327:243-253. [PMID: 29356454 DOI: 10.1002/jez.2081] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 05/30/2017] [Accepted: 06/21/2017] [Indexed: 11/07/2022]
Abstract
An individual's investment in constitutive immune defenses depends on both intrinsic and extrinsic factors. We examined how Leucocytozoon parasite presence, body condition (scaled mass), heterophil-to-lymphocyte (H:L) ratio, sex, and age affected immune defenses in golden eagle (Aquila chrysaetos) nestlings from three regions: California, Oregon, and Idaho. We quantified hemolytic-complement activity and bacterial killing ability, two measures of constitutive immunity. Body condition and age did not affect immune defenses. However, eagles with lower H:L ratios had lower complement activity, corroborating other findings that animals in better condition sometimes invest less in constitutive immunity. In addition, eagles with Leucocytozoon infections had higher concentrations of circulating complement proteins but not elevated opsonizing proteins for all microbes, and eagles from Oregon had significantly higher constitutive immunity than those from California or Idaho. We posit that Oregon eagles might have elevated immune defenses because they are exposed to more endoparasites than eagles from California or Idaho, and our results confirmed that the OR region has the highest rate of Leucocytozoon infections. Our study examined immune function in a free-living, long-lived raptor species, whereas most avian ecoimmunological research focuses on passerines. Thus, our research informs a broad perspective regarding the evolutionary and environmental pressures on immune function in birds.
Collapse
Affiliation(s)
| | - Kris Vanesky
- Academy for the Environment, University of Nevada Reno, NV, USA
| | - Jeremy A Buck
- US Fish and Wildlife Service, Oregon Fish and Wildlife Office, Portland, OR, USA
| | - Benjamin M Dudek
- Department of Biological Sciences and Raptor Research Center, Boise State University, Boise, ID, USA
| | - Collin A Eagles-Smith
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, Corvallis, OR
| | - Julie A Heath
- Department of Biological Sciences and Raptor Research Center, Boise State University, Boise, ID, USA
| | - Garth Herring
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, Corvallis, OR
| | - Chris Vennum
- Department of Biology, University of Nevada, Reno, NV, USA
| | | |
Collapse
|
48
|
Needham KB, Dochtermann NA, Greives TJ. Consistent individual variation in day, night, and GnRH-induced testosterone concentrations in house sparrows (Passer domesticus). Gen Comp Endocrinol 2017; 246:211-217. [PMID: 28017731 DOI: 10.1016/j.ygcen.2016.12.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Revised: 12/13/2016] [Accepted: 12/19/2016] [Indexed: 11/25/2022]
Abstract
The hypothalamic-pituitary-gonadal (HPG) axis, with gonadotropin-releasing hormone (GnRH) initiating the endocrine cascade, regulates testosterone secretion. Testosterone, through its pleiotropic effects, plays a crucial role in coordinating morphology, physiology and behavior in a reproductive context. The concentration of circulating testosterone, however, varies over the course of the day and in response to other internal or external stimuli, potentially making it difficult to relate testosterone sampled at one time point with traits of interest. Many researchers now utilize the administration of exogenous GnRH to elicit a standardized stimulation of testosterone secretion. However, it has remained unclear if and how this exogenously stimulated activation of the HPG axis is related with endogenously regulated testosterone that is capable of influencing testosterone related traits. Repeated measures of a hormone can uncover consistent individual variation in hormonal differences at the HPG axis level, variation that potentially stems from underlying genetic variation in a population experiencing identical environmental cues. Thus, we asked, using the house sparrow (Passer domesticus), how daily endogenous variation in testosterone profiles relates to GnRH-induced testosterone secretion. Further, we explore the relationship between endogenous daily testosterone peaks and GnRH-induced testosterone with badge size, a morphological trait related with status within a social group. We found that GnRH-induced testosterone levels reflect a highly repeatable hormonal phenotype that is strongly correlated with nighttime testosterone levels. The results demonstrate the usefulness of GnRH-induced testosterone in studies aimed at understanding individual variation and selection on endogenously regulated testosterone levels and the potential importance of nighttime testosterone levels to physiology and behavior.
Collapse
Affiliation(s)
- Katie B Needham
- Department of Biological Sciences, North Dakota State University, Fargo, ND 58102, USA.
| | - Ned A Dochtermann
- Department of Biological Sciences, North Dakota State University, Fargo, ND 58102, USA
| | - Timothy J Greives
- Department of Biological Sciences, North Dakota State University, Fargo, ND 58102, USA
| |
Collapse
|