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Knutie SA, Webster CN, Vaziri GJ, Albert L, Harvey JA, LaRue M, Verrett TB, Soldo A, Koop JAH, Chaves JA, Wegrzyn JL. Urban living can rescue Darwin's finches from the lethal effects of invasive vampire flies. GLOBAL CHANGE BIOLOGY 2024; 30:e17145. [PMID: 38273516 DOI: 10.1111/gcb.17145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 12/15/2023] [Accepted: 12/21/2023] [Indexed: 01/27/2024]
Abstract
Human activity changes multiple factors in the environment, which can have positive or negative synergistic effects on organisms. However, few studies have explored the causal effects of multiple anthropogenic factors, such as urbanization and invasive species, on animals and the mechanisms that mediate these interactions. This study examines the influence of urbanization on the detrimental effect of invasive avian vampire flies (Philornis downsi) on endemic Darwin's finches in the Galápagos Islands. We experimentally manipulated nest fly abundance in urban and non-urban locations and then characterized nestling health, fledging success, diet, and gene expression patterns related to host defense. Fledging success of non-parasitized nestlings from urban (79%) and non-urban (75%) nests did not differ significantly. However, parasitized, non-urban nestlings lost more blood, and fewer nestlings survived (8%) compared to urban nestlings (50%). Stable isotopic values (δ15 N) from urban nestling feces were higher than those from non-urban nestlings, suggesting that urban nestlings are consuming more protein. δ15 N values correlated negatively with parasite abundance, which suggests that diet might influence host defenses (e.g., tolerance and resistance). Parasitized, urban nestlings differentially expressed genes within pathways associated with red blood cell production (tolerance) and pro-inflammatory response (innate immunological resistance), compared to parasitized, non-urban nestlings. In contrast, parasitized non-urban nestlings differentially expressed genes within pathways associated with immunoglobulin production (adaptive immunological resistance). Our results suggest that urban nestlings are investing more in pro-inflammatory responses to resist parasites but also recovering more blood cells to tolerate blood loss. Although non-urban nestlings are mounting an adaptive immune response, it is likely a last effort by the immune system rather than an effective defense against avian vampire flies since few nestlings survived.
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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
| | - Cynthia N Webster
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Grace J Vaziri
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Lauren Albert
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Johanna A Harvey
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
- Department of Science and Technology, University of Maryland, College Park, Maryland, USA
| | - Michelle LaRue
- School of Earth and Environment, University of Canterbury, Christchurch, New Zealand
| | - Taylor B Verrett
- 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
| | - Jennifer A H Koop
- Department of Biological Sciences, Northern Illinois University, DeKalb, Illinois, USA
| | - Jaime A Chaves
- Department of Biology, San Francisco State University, San Francisco, California, USA
- Colegio de Ciencias Biológicas y Ambientales, Universidad San Francisco de Quito, Quito, Ecuador
| | - Jill L Wegrzyn
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
- Institute for Systems Genomics, University of Connecticut, Storrs, Connecticut, USA
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2
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Solomon G, Love AC, Vaziri GJ, Harvey J, Verrett T, Chernicky K, Simons S, Albert L, Chaves JA, Knutie SA. Effect of urbanization and parasitism on the gut microbiota of Darwin's finch nestlings. Mol Ecol 2023; 32:6059-6069. [PMID: 37837269 DOI: 10.1111/mec.17164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 09/20/2023] [Accepted: 10/02/2023] [Indexed: 10/15/2023]
Abstract
Host-associated microbiota can be affected by factors related to environmental change, such as urbanization and invasive species. For example, urban areas often affect food availability for animals, which can change their gut microbiota. Invasive parasites can also influence microbiota through competition or indirectly through a change in the host immune response. These interacting factors can have complex effects on host fitness, but few studies have disentangled the relationship between urbanization and parasitism on an organism's gut microbiota. To address this gap in knowledge, we investigated the effects of urbanization and parasitism by the invasive avian vampire fly (Philornis downsi) on the gut microbiota of nestling small ground finches (Geospiza fuliginosa) on San Cristóbal Island, Galápagos. We conducted a factorial study in which we experimentally manipulated parasite presence in an urban and nonurban area. Faeces were then collected from nestlings to characterize the gut microbiota (i.e. bacterial diversity and community composition). Although we did not find an interactive effect of urbanization and parasitism on the microbiota, we did find main effects of each variable. We found that urban nestlings had lower bacterial diversity and different relative abundances of taxa compared to nonurban nestlings, which could be mediated by introduction of the microbiota of the food items or changes in host physiology. Additionally, parasitized nestlings had lower bacterial richness than nonparasitized nestlings, which could be mediated by a change in the immune system. Overall, this study advances our understanding of the complex effects of anthropogenic stressors on the gut microbiota of birds.
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Affiliation(s)
- Gabrielle Solomon
- Department of Ecology and Evolutionary Biology, University of Connecticut, Connecticut, Storrs, USA
| | - Ashley C Love
- Department of Ecology and Evolutionary Biology, University of Connecticut, Connecticut, Storrs, USA
| | - Grace J Vaziri
- Department of Ecology and Evolutionary Biology, University of Connecticut, Connecticut, Storrs, USA
| | - Johanna Harvey
- Department of Ecology and Evolutionary Biology, University of Connecticut, Connecticut, Storrs, USA
| | - Taylor Verrett
- Department of Ecology and Evolutionary Biology, University of Connecticut, Connecticut, Storrs, USA
| | - Kiley Chernicky
- Department of Ecology and Evolutionary Biology, University of Connecticut, Connecticut, Storrs, USA
| | - Shelby Simons
- Department of Ecology and Evolutionary Biology, University of Connecticut, Connecticut, Storrs, USA
| | - Lauren Albert
- Department of Ecology and Evolutionary Biology, University of Connecticut, Connecticut, Storrs, USA
| | - Jaime A Chaves
- Colegio de Ciencias Biológicas y Ambientales, Universidad San Francisco de Quito, Quito, Ecuador
- Galapagos Science Center, Puerto Baquerizo Moreno, Galapagos, Ecuador
- Department of Biology, San Francisco State University, California, San Francisco, USA
| | - Sarah A Knutie
- Department of Ecology and Evolutionary Biology, University of Connecticut, Connecticut, Storrs, USA
- Colegio de Ciencias Biológicas y Ambientales, Universidad San Francisco de Quito, Quito, Ecuador
- Institute for Systems Genomics, University of Connecticut, Connecticut, Storrs, USA
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3
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Pike CL, Kofler B, Richner H, Tebbich S. Parental food provisioning and nestling growth under Philornis downsi parasitism in the Galapagos Green Warbler-Finch, classified as 'vulnerable' by the IUCN. JOURNAL OF ORNITHOLOGY 2023; 164:669-676. [PMID: 37205902 PMCID: PMC10188583 DOI: 10.1007/s10336-023-02049-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 01/31/2023] [Accepted: 02/04/2023] [Indexed: 05/21/2023]
Abstract
In the Galapagos Islands, many endemic landbird populations are declining due to habitat degradation, food availability, introduced species and other factors. Given nestlings typically lack efficient defense mechanisms against parasites, hematophagous ectoparasites such as the larvae of the introduced Avian Vampire Fly, Philornis downsi, can impose high brood mortality and cause threatening population declines in Darwin finches and other landbirds. Here, we assess whether the food compensation hypothesis (i.e., the parents' potential to compensate for deleterious parasite effects via increased food provisioning) applies to the Green Warbler-Finch. We differentiated nests with low or high infestation levels by P. downsi and quantified food provisioning rates of male and female parents, time females spent brooding nestlings, and nestling growth. Male provisioning rates, total provisioning rates and female brooding time did not significantly vary in relation to infestation levels, nor by the number of nestlings. Opposed to the predictions of the food compensation hypothesis, females showed significantly reduced provisioning rates at high infestation levels. Nestling body mass was significantly lower and there was a reduction of skeletal growth, although not significantly, in highly infested nests. The females' response to high infestation may be due to parasites directly attacking and weakening brooding females, or else that females actively reduce current reproductive effort in favor of future reproduction. This life-history trade-off may be typical for Darwin finches and many tropical birds with long lifespans and therefore high residual reproductive value. Conservation strategies may not build on the potential for parental food compensation by this species.
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Affiliation(s)
- Courtney L. Pike
- Department of Behavioral and Cognitive Biology, University of Vienna, Vienna, Vienna Austria
| | - Barbara Kofler
- Department of Behavioral and Cognitive Biology, University of Vienna, Vienna, Vienna Austria
| | - Heinz Richner
- Department of Biology, University of Bern, Bern, Bern Switzerland
| | - Sabine Tebbich
- Department of Behavioral and Cognitive Biology, University of Vienna, Vienna, Vienna Austria
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Romine MG, Knutie SA, Crow CM, Vaziri GJ, Chaves JA, Koop JAH, Lamichhaney S. The genome sequence of the avian vampire fly ( Philornis downsi), an invasive nest parasite of Darwin’s finches in Galápagos. G3 GENES|GENOMES|GENETICS 2022; 12:6456303. [PMID: 34878103 PMCID: PMC9210292 DOI: 10.1093/g3journal/jkab414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 11/15/2021] [Indexed: 11/14/2022]
Abstract
The invasive avian vampire fly (Philornis downsi, Diptera: Muscidae) is considered one of the greatest threats to the endemic avifauna of the Galápagos Islands. The fly larvae parasitize nearly every passerine species, including Darwin’s finches. Most P. downsi research to date has focused on the effects of the fly on avian host fitness and mitigation methods. A lag in research related to the genetics of this invasion demonstrates, in part, the need to develop full-scale genomic resources with which to address further questions within this system. In this study, an adult female P. downsi was sequenced to generate a high-quality genome assembly. We examined various features of the genome (e.g., coding regions and noncoding transposable elements) and carried out comparative genomics analysis against other dipteran genomes. We identified lists of gene families that are significantly expanding or contracting in P. downsi that are related to insecticide resistance, detoxification, and counter defense against host immune responses. The P. downsi genome assembly provides an important resource for studying the molecular basis of successful invasion in the Galápagos and the dynamics of its population across multiple islands. The findings of significantly changing gene families associated with insecticide resistance and immune responses highlight the need for further investigations into the role of different gene families in aiding the fly’s successful invasion. Furthermore, this genomic resource provides a necessary tool to better inform future research studies and mitigation strategies aimed at minimizing the fly’s impact on Galápagos birds.
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Affiliation(s)
- Melia G Romine
- School of Biomedical Sciences, Kent State University, Kent, OH 44240, USA
| | - Sarah A Knutie
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
- Institute for Systems Genomics, University of Connecticut, Storrs, CT 06269, USA
| | - Carly M Crow
- Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115, USA
| | - Grace J Vaziri
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
| | - Jaime A Chaves
- Department of Biology, San Francisco State University, San Francisco, CA 94132, USA
- Colegio de Ciencias Biológicas y Ambientales, Universidad San Francisco de Quito, Quito 170901, Ecuador
| | - Jennifer A H Koop
- Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115, USA
| | - Sangeet Lamichhaney
- School of Biomedical Sciences, Kent State University, Kent, OH 44240, USA
- Department of Biological Sciences, Kent State University, Kent, OH 44240, USA
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Kleindorfer S, Common LK, O'Connor JA, Garcia-Loor J, Katsis AC, Dudaniec RY, Colombelli-Négrel D, Adreani NM. Female in-nest attendance predicts the number of ectoparasites in Darwin's finch species. Proc Biol Sci 2021; 288:20211668. [PMID: 34905711 PMCID: PMC8670954 DOI: 10.1098/rspb.2021.1668] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 11/19/2021] [Indexed: 11/12/2022] Open
Abstract
Selection should act on parental care and favour parental investment decisions that optimize the number of offspring produced. Such predictions have been robustly tested in predation risk contexts, but less is known about alternative functions of parental care under conditions of parasitism. The avian vampire fly (Philornis downsi) is a myasis-causing ectoparasite accidentally introduced to the Galápagos Islands, and one of the major mortality causes in Darwin's finch nests. With an 11-year dataset spanning 21 years, we examine the relationship between parental care behaviours and number of fly larvae and pupae in Darwin's finch nests. We do so across three host species (Camarhynchus parvulus, C. pauper, Geospiza fuliginosa) and one hybrid Camarhynchus group. Nests with longer female brooding duration (minutes per hour spent sitting on hatchlings to provide warmth) had fewer parasites, and this effect depended on male food delivery to chicks. Neither male age nor number of nest provisioning visits were directly associated with number of parasites. While the causal mechanisms remain unknown, we provide the first empirical study showing that female brooding duration is negatively related to the number of ectoparasites in nests. We predict selection for coordinated host male and female behaviour to reduce gaps in nest attendance, especially under conditions of novel and introduced ectoparasites.
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Affiliation(s)
- Sonia Kleindorfer
- College of Science and Engineering, Flinders University, Adelaide 5001, Australia
- Konrad Lorenz Research Center for Behavior and Cognition and Department of Behavioral and Cognitive Biology, University of Vienna, Vienna 1090, Austria
| | - Lauren K. Common
- College of Science and Engineering, Flinders University, Adelaide 5001, Australia
| | | | - Jefferson Garcia-Loor
- Konrad Lorenz Research Center for Behavior and Cognition and Department of Behavioral and Cognitive Biology, University of Vienna, Vienna 1090, Austria
- Charles Darwin Research Station, Galápagos, Ecuador
| | - Andrew C. Katsis
- College of Science and Engineering, Flinders University, Adelaide 5001, Australia
| | - Rachael Y. Dudaniec
- Department of Biological Sciences, Macquarie University, Sydney 2109, Australia
| | | | - Nico M. Adreani
- Konrad Lorenz Research Center for Behavior and Cognition and Department of Behavioral and Cognitive Biology, University of Vienna, Vienna 1090, Austria
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Nesting Success and Nesting Height in the Critically Endangered Medium Tree Finch (Camarhynchus pauper). BIRDS 2021. [DOI: 10.3390/birds2040032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
When different introduced species across trophic levels (parasite, predator) invade island systems, they may pose significant threats to nesting birds. In this study, we measure nesting height and infer causes of offspring mortality in the critically endangered Medium Tree Finch (Camarhynchus pauper), an island endemic restricted to Floreana Island on the Galápagos Archipelago. Considering all nests at which a male built a nest, sang and attempted to attract a female (n = 222 nests), only 10.4% of nests produced fledglings (5% of nests had total fledging success, 5.4% of nests had partial fledging success). Of the 123 nests chosen by a female, 18.7% produced fledglings and of 337 eggs laid, 13.4% produced fledglings. Pairing success was higher for older males, but male age did not predict nesting success. All nests with chicks were infested with avian vampire fly larvae (Philornis downsi). We attributed the cause of death to avian vampire fly if chicks were found dead in the nest with fly larvae or pupae (45%) present. We inferred avian (either Asio flammeus galapagoensis or Crotophaga ani) predation (24%) if the nest was empty but dishevelled; and black rat (Rattus rattus) predation (20%) if the nest was empty but undamaged. According to these criteria, the highest nests were depredated by avian predators, the lowest nests by rats, and intermediate nests failed because of avian vampire fly larvae. In conclusion, there is no safe nesting height on Floreana Island under current conditions of threats from two trophic levels (introduced parasitic dipteran, introduced mammalian/avian predators; with Galápagos Short-Eared Owls being the only native predator in the system).
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Romano A, Corti M, Soravia C, Cecere JG, Rubolini D. Ectoparasites exposure affects early growth and mouth colour in nestlings of a cavity-nesting raptor. Behav Ecol Sociobiol 2021. [DOI: 10.1007/s00265-021-03098-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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8
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Common LK, Sumasgutner P, Dudaniec RY, Colombelli-Négrel D, Kleindorfer S. Avian vampire fly (Philornis downsi) mortality differs across Darwin's finch host species. Sci Rep 2021; 11:15832. [PMID: 34349147 PMCID: PMC8338931 DOI: 10.1038/s41598-021-94996-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 07/19/2021] [Indexed: 12/03/2022] Open
Abstract
In invasive parasites, generalism is considered advantageous during the initial phase of introduction. Thereafter, fitness costs to parasites, such as host-specific mortality, can drive parasites towards specialism to avoid costly hosts. It is important to determine changes in host specificity of invasive populations to understand host-parasite dynamics and their effects on vulnerable host populations. We examined changes in mortality in the introduced avian vampire fly (Philornis downsi) (Diptera: Muscidae), a generalist myasis-causing ectoparasite, between 2004 and 2020 on Floreana Island (Galápagos). Mortality was measured as the proportion of immature larvae found upon host nest termination. Over the time period, the avian vampire fly was most abundant and had low mortality in nests of the critically endangered medium tree finch (Camarhynchus pauper) and had the highest mortality in nests of hybrid tree finches (Camarhynchus spp.). Low larval mortality was also found in small tree (Camarhynchus parvulus) and small ground finch (Geospiza fuliginosa) nests. Selection could favour avian vampire flies that select medium tree finch nests and/or avoid hybrid nests. Overall, the finding of differences in avian vampire fly survival across host species is parsimonious with the idea that the introduced fly may be evolving towards host specialisation.
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Affiliation(s)
- Lauren K Common
- College of Science and Engineering, Flinders University, Bedford Park, SA, 5001, Australia
| | - Petra Sumasgutner
- Department of Behavioral and Cognitive Biology, Konrad Lorenz Research Center, Core Facility for Behavior and Cognition, University of Vienna, Vienna, Austria
| | - Rachael Y Dudaniec
- Department of Biological Sciences, Macquarie University, Sydney, NSW , 2109, Australia
| | | | - Sonia Kleindorfer
- College of Science and Engineering, Flinders University, Bedford Park, SA, 5001, Australia. .,Department of Behavioral and Cognitive Biology, Konrad Lorenz Research Center, Core Facility for Behavior and Cognition, University of Vienna, Vienna, Austria.
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9
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Katsis AC, Colombelli-Négrel D, Common LK, O’connor JA, Dudaniec RY, García-Loor J, Kleindorfer S. Nestling behaviour predicts naris deformation in Darwin’s finches parasitized by the avian vampire fly. Biol J Linn Soc Lond 2021. [DOI: 10.1093/biolinnean/blab092] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Although in-nest parasitism can reduce the fitness of avian hosts, the severity of these effects may vary with host physiology and behaviour. If certain nestling behaviours are beneficial for resisting parasitism, then selection may favour some behavioural phenotypes over others. Here, we tested whether differences in nestling behaviour mediate the negative effects of parasitism, using small ground finches (Geospiza fuliginosa), on Floreana Island, that had been parasitized by the invasive avian vampire fly (Philornis downsi). We first established, using 4 years of breeding data (2005, 2006, 2010 and 2020), that nestlings exposed to more parasites had larger nares and, among older nestlings only, lower body mass. We then examined, using data from the 2020 season, whether each nestling’s behaviour (specifically, its response to human handling) predicted the severity of its naris deformation. When faced with high-intensity parasitism, more responsive nestlings (i.e. those that struggled more during handling) had larger nares compared to more docile nestlings. This suggests that more responsive nestlings suffer greater fitness costs due to parasitism, although we also discuss alternative explanations. Future work should consider the stability and heritability of these nestling behavioural differences and whether parasite-induced selection shapes behavioural variation at the population level.
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Affiliation(s)
- Andrew C Katsis
- College of Science and Engineering, Flinders University, Adelaide, South Australia, Australia
| | - Diane Colombelli-Négrel
- College of Science and Engineering, Flinders University, Adelaide, South Australia, Australia
| | - Lauren K Common
- College of Science and Engineering, Flinders University, Adelaide, South Australia, Australia
| | - Jody A O’connor
- College of Science and Engineering, Flinders University, Adelaide, South Australia, Australia
- Department for Environment and Water, Government of South Australia, Adelaide, South Australia, Australia
| | - Rachael Y Dudaniec
- Department of Biological Sciences, Macquarie University, Sydney, New South Wales, Australia
| | | | - Sonia Kleindorfer
- College of Science and Engineering, Flinders University, Adelaide, South Australia, Australia
- Konrad Lorenz Research Centre for Behaviour and Cognition and Department of Behavioural and Cognitive Biology, University of Vienna, Vienna, Austria
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Heyer E, Cimadom A, Wappl C, Tebbich S. Parental care in the Small Tree Finch Camarhynchus parvulus in relation to parasitism and environmental factors. THE IBIS 2021; 163:137-149. [PMID: 33362293 PMCID: PMC7754105 DOI: 10.1111/ibi.12845] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 04/28/2020] [Indexed: 05/30/2023]
Abstract
The parental food compensation hypothesis suggests that parents may compensate for the negative effects of parasites on chicks by increased food provisioning. However, this ability differs widely among host species and may also depend on ecological factors such as adverse weather conditions and habitat quality. Although weed management can improve habitat quality, management measures can bring about a temporary decrease in food availability and thus may reduce parents' ability to provide their nestlings with enough energy. In our study we investigated the interaction of parasitism and weed management, and the influence of climate on feeding rates in a Darwin's tree finch species, which is negatively impacted by two invasive species. The larvae of the invasive parasitic fly Philornis downsi ingest the blood and body tissues of tree finch nestlings, and the invasive Blackberry Rubus niveus affects one of the main habitats of Darwin's tree finches. We compared parental food provisioning of the Small Tree Finch Camarhynchus parvulus in parasitized and parasite-free nests in three different areas, which differed in invasive weed management (no management, short-term and long-term management). In a parasite reduction experiment, we investigated whether the Small Tree Finch increases food provisioning rates to nestlings when parasitized and whether this ability depends on weed management conditions and precipitation. Our results provide no evidence that Small Tree Finches can compensate with additional food provisioning when parasitized with P. downsi. However, we found an increase in male effort in the short-term management area, which might indicate that males compensate for lower food quality with increased provisioning effort. Furthermore, parental food provisioning was lower during rainfall, which provides an explanation for the negative influence of rain on breeding success found in earlier studies. Like other Darwin's finches, the Small Tree Finch seems to lack the ability to compensate for the negative effects of P. downsi parasitism, which is one explanation for why this invasive parasite has such a devastating effect on this host species.
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Affiliation(s)
- Eileen Heyer
- Department of Behavioural BiologyUniversity of ViennaAlthanstraße 141090ViennaAustria
| | - Arno Cimadom
- Department of Behavioural BiologyUniversity of ViennaAlthanstraße 141090ViennaAustria
| | - Christian Wappl
- Department of Behavioural BiologyUniversity of ViennaAlthanstraße 141090ViennaAustria
| | - Sabine Tebbich
- Department of Behavioural BiologyUniversity of ViennaAlthanstraße 141090ViennaAustria
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11
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Ohmer MEB, Costantini D, Czirják GÁ, Downs CJ, Ferguson LV, Flies A, Franklin CE, Kayigwe AN, Knutie S, Richards-Zawacki CL, Cramp RL. Applied ecoimmunology: using immunological tools to improve conservation efforts in a changing world. CONSERVATION PHYSIOLOGY 2021; 9:coab074. [PMID: 34512994 PMCID: PMC8422949 DOI: 10.1093/conphys/coab074] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 07/27/2021] [Accepted: 08/09/2021] [Indexed: 05/11/2023]
Abstract
Ecoimmunology is a rapidly developing field that explores how the environment shapes immune function, which in turn influences host-parasite relationships and disease outcomes. Host immune defence is a key fitness determinant because it underlies the capacity of animals to resist or tolerate potential infections. Importantly, immune function can be suppressed, depressed, reconfigured or stimulated by exposure to rapidly changing environmental drivers like temperature, pollutants and food availability. Thus, hosts may experience trade-offs resulting from altered investment in immune function under environmental stressors. As such, approaches in ecoimmunology can provide powerful tools to assist in the conservation of wildlife. Here, we provide case studies that explore the diverse ways that ecoimmunology can inform and advance conservation efforts, from understanding how Galapagos finches will fare with introduced parasites, to using methods from human oncology to design vaccines against a transmissible cancer in Tasmanian devils. In addition, we discuss the future of ecoimmunology and present 10 questions that can help guide this emerging field to better inform conservation decisions and biodiversity protection. From better linking changes in immune function to disease outcomes under different environmental conditions, to understanding how individual variation contributes to disease dynamics in wild populations, there is immense potential for ecoimmunology to inform the conservation of imperilled hosts in the face of new and re-emerging pathogens, in addition to improving the detection and management of emerging potential zoonoses.
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Affiliation(s)
- Michel E B Ohmer
- Living Earth Collaborative, Washington University in St. Louis, MO 63130, USA
| | - David Costantini
- Unité Physiologie Moléculaire et Adaptation (PhyMA), Muséum National d’Histoire Naturelle, CNRS, 57 Rue Cuvier, CP32, 75005, Paris, France
| | - Gábor Á Czirják
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, 10315 Berlin, Germany
| | - Cynthia J Downs
- Department of Environmental Biology, SUNY College of Environmental Science and Forestry, Syracuse, NY 13210, USA
| | - Laura V Ferguson
- Department of Psychology and Neuroscience, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Andy Flies
- Menzies Institute for Medical Research, University of Tasmania, Tasmania 7001, Australia
| | - Craig E Franklin
- School of Biological Sciences, The University of Queensland, Queensland 4072, Australia
| | - Ahab N Kayigwe
- Menzies Institute for Medical Research, University of Tasmania, Tasmania 7001, Australia
| | - Sarah Knutie
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06268, USA
- Institute for Systems Genomics, University of Connecticut, Storrs, CT 06268, USA
| | | | - Rebecca L Cramp
- School of Biological Sciences, The University of Queensland, Queensland 4072, Australia
- Corresponding author: School of Biological Sciences, The University of Queensland, Queensland 4072, Australia.
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Timing of infestation influences virulence and parasite success in a dynamic multi-host-parasite interaction between the invasive parasite, Philornis downsi, and Darwin's finches. Oecologia 2020; 195:249-259. [PMID: 33258992 PMCID: PMC7882474 DOI: 10.1007/s00442-020-04807-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Accepted: 11/16/2020] [Indexed: 12/30/2022]
Abstract
Recently commenced host–parasite interactions provide an excellent opportunity to study co-evolutionary processes. Multi-host systems are especially informative because variation in virulence between hosts and temporal changes provides insight into evolutionary dynamics. However, empirical data under natural conditions are scarce. In the present study, we investigated the interaction between Darwin’s finches and the invasive fly Philornis downsi whose larvae feed on the blood of nestlings. Recently, however, the fly has changed its behavior and now also attacks incubating females. Two sympatric hosts are affected differently by the parasite and parasite load has changed over time. Our study observed a reversal of trends described two decades ago: while, currently, small tree finches (Camarhynchus parvulus) experience significantly higher parasite load than warbler finches (Certhidea olivacea), this was the opposite two decades ago. Currently, fledging success is higher in warbler finches compared to small tree finches. Our data indicate that not only intensity but also timing of infestation influences hosts’ reproductive success and parasite fitness. During incubation, prevalence was higher in warbler finches, but once chicks had hatched, prevalence was 100% in both species and parasite load was higher in small tree finches. Furthermore, our results suggest faster development and higher reproductive success of P. downsi in small tree finch nests. A change in host preference driven by larvae competition could have led to the reversal in parasite load.
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Wappl C, Cimadom A, Filek N, Heyer E, Tebbich S. Under adverse conditions, older small tree finch males ( Camarhynchus parvulus) produce more offspring than younger males. Ethology 2020; 126:966-975. [PMID: 33162627 PMCID: PMC7604768 DOI: 10.1111/eth.13069] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Revised: 04/29/2020] [Accepted: 05/04/2020] [Indexed: 11/30/2022]
Abstract
Females of many bird species prefer mating with older males, presumably because they provide superior parental care and possibly superior genes. A previous study found that female small tree finches (Camarhynchus parvulus) preferred pairing with old males and had a higher breeding success when paired with old males because their nests were more concealed, higher up in the canopy and therefore less likely to be depredated. However, causes for brood loss have changed over the last decade: predation of small tree finch nests has decreased, whereas brood losses due to parasitism by the invasive parasitic fly Philornis downsi have increased. In the present study, we investigated (a) how the change in predation and parasitism by P. downsi influenced the breeding success of small tree finches, (b) whether there were still differences in breeding success between young and old males, (c) whether P. downsi infestation had a differential effect on nests of young and old males and (d) whether young and old males differed in foraging success. During 2012-2016, we found an overall low influence of predation and a high influence of P. downsi, but neither differed between nests of young and old males. Nests of old males had more fledglings than those of young males. However, the difference in breeding success disappeared when P. downsi numbers were experimentally reduced by injecting an insecticide into nests. This indicates that older males were able to compensate for the detrimental effects of parasitism.
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Affiliation(s)
- Christian Wappl
- Department of Behavioural BiologyUniversity of ViennaViennaAustria
| | - Arno Cimadom
- Department of Behavioural BiologyUniversity of ViennaViennaAustria
| | - Nikolaus Filek
- Department of Behavioural BiologyUniversity of ViennaViennaAustria
| | - Eileen Heyer
- Department of Behavioural BiologyUniversity of ViennaViennaAustria
| | - Sabine Tebbich
- Department of Behavioural BiologyUniversity of ViennaViennaAustria
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14
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Bulgarella M, Knutie SA, Voss MA, Cunninghame F, Florence-Bennett BJ, Robson G, Keyzers RA, Taylor LM, Lester PJ, Heimpel GE, Causton CE. Sub-lethal effects of permethrin exposure on a passerine: implications for managing ectoparasites in wild bird nests. CONSERVATION PHYSIOLOGY 2020; 8:coaa076. [PMID: 32908668 PMCID: PMC7416766 DOI: 10.1093/conphys/coaa076] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 07/10/2020] [Accepted: 07/26/2020] [Indexed: 06/11/2023]
Abstract
Permethrin is increasingly used for parasite control in bird nests, including nests of threatened passerines. We present the first formal evaluation of the effects of continued permethrin exposure on the reproductive success and liver function of a passerine, the zebra finch (Taeniopygia guttata), for two generations. We experimentally treated all nest material with a 1% permethrin solution or a water control and provided the material to breeding finches for nest building. The success of two consecutive clutches produced by the parental generation and one clutch produced by first-generation birds were tracked. Finches in the first generation were able to reproduce and fledge offspring after permethrin exposure, ruling out infertility. Permethrin treatment had no statistically significant effect on the number of eggs laid, number of days from clutch initiation to hatching, egg hatch rate, fledgling mass or nestling sex ratio in either generation. However, treating nest material with permethrin significantly increased the number of hatchlings in the first generation and decreased fledgling success in the second generation. Body mass for hatchlings exposed to permethrin was lower than for control hatchlings in both generations, but only statistically significant for the second generation. For both generations, an interaction between permethrin treatment and age significantly affected nestling growth. Permethrin treatment had no effect on liver function for any generation. Permethrin was detected inside 6 of 21 exposed, non-embryonated eggs (28.5% incidence; range: 693-4781 ng of permethrin per gram of dry egg mass). Overall, results from exposing adults, eggs and nestlings across generations to permethrin-treated nest material suggest negative effects on finch breeding success, but not on liver function. For threatened bird conservation, the judicious application of this insecticide to control parasites in nests can result in lower nestling mortality compared to when no treatment is applied. Thus, permethrin treatment benefits may outweigh its sub-lethal effects.
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Affiliation(s)
- Mariana Bulgarella
- School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington, 6140, New Zealand
| | - Sarah A Knutie
- Department of Ecology and Evolutionary Biology, University of Connecticut, 75 N. Eagleville Road, Unit 3043, Storrs, CT, 06269, USA
| | | | - Francesca Cunninghame
- Charles Darwin Research Station, Charles Darwin Foundation, Puerto Ayora, Santa Cruz Island, Galápagos Islands, Ecuador
| | | | - Gemma Robson
- School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington, 6140, New Zealand
| | - Robert A Keyzers
- School of Chemical and Physical Sciences, Victoria University of Wellington, PO Box 600, Wellington, 6140, New Zealand
| | - Lauren M Taylor
- School of Chemical and Physical Sciences, Victoria University of Wellington, PO Box 600, Wellington, 6140, New Zealand
| | - Philip J Lester
- School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington, 6140, New Zealand
| | - George E Heimpel
- Department of Entomology, University of Minnesota, 1980 Folwell Avenue, St. Paul, MN, 55108, USA
| | - Charlotte E Causton
- Charles Darwin Research Station, Charles Darwin Foundation, Puerto Ayora, Santa Cruz Island, Galápagos Islands, Ecuador
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15
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Common LK, O'Connor JA, Dudaniec RY, Peters KJ, Kleindorfer S. Evidence for rapid downward fecundity selection in an ectoparasite (Philornis downsi) with earlier host mortality in Darwin's finches. J Evol Biol 2020; 33:524-533. [PMID: 31961983 PMCID: PMC7217188 DOI: 10.1111/jeb.13588] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 01/09/2020] [Accepted: 01/15/2020] [Indexed: 01/05/2023]
Abstract
Fecundity selection is a critical component of fitness and a major driver of adaptive evolution. Trade‐offs between parasite mortality and host resources are likely to impose a selection pressure on parasite fecundity, but this is little studied in natural systems. The ‘fecundity advantage hypothesis’ predicts female‐biased sexual size dimorphism whereby larger females produce more offspring. Parasitic insects are useful for exploring the interplay between host resource availability and parasite fecundity, because female body size is a reliable proxy for fecundity in insects. Here we explore temporal changes in body size in the myiasis‐causing parasite Philornis downsi (Diptera: Muscidae) on the Galápagos Islands under conditions of earlier in‐nest host mortality. We aim to investigate the effects of decreasing host resources on parasite body size and fecundity. Across a 12‐year period, we observed a mean of c. 17% P. downsi mortality in host nests with 55 ± 6.2% host mortality and a trend of c. 66% higher host mortality throughout the study period. Using specimens from 116 Darwin's finch nests (Passeriformes: Thraupidae) and 114 traps, we found that over time, P. downsi pupae mass decreased by c. 32%, and male (c. 6%) and female adult size (c. 11%) decreased. Notably, females had c. 26% smaller abdomens in later years, and female abdomen size was correlated with number of eggs. Our findings imply natural selection for faster P. downsi pupation and consequently smaller body size and lower parasite fecundity in this newly evolving host–parasite system.
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Affiliation(s)
- Lauren K Common
- College of Science and Engineering, Flinders University, Adelaide, SA, Australia
| | - Jody A O'Connor
- College of Science and Engineering, Flinders University, Adelaide, SA, Australia.,Department for Environment and Water, Government of South Australia, Adelaide, SA, Australia
| | - Rachael Y Dudaniec
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
| | - Katharina J Peters
- College of Science and Engineering, Flinders University, Adelaide, SA, Australia
| | - Sonia Kleindorfer
- College of Science and Engineering, Flinders University, Adelaide, SA, Australia.,Konrad Lorenz Research Center for Behaviour and Cognition and Department of Behavioural and Cognitive Biology, University of Vienna, Vienna, Austria
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16
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McNew SM, Goodman GB, Yépez R J, Clayton DH. Parasitism by an invasive nest fly reduces future reproduction in Galápagos mockingbirds. Oecologia 2020; 192:363-374. [PMID: 31897722 DOI: 10.1007/s00442-019-04582-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Accepted: 12/13/2019] [Indexed: 11/30/2022]
Abstract
Organisms allocate limited resources to competing activities such as reproduction, growth, and defense against parasites and predators. The introduction of a novel parasite may create new life history trade-offs. As hosts increase their investment in self-maintenance or defense, the cost of parasitism may carry over to other aspects of host biology. Here, in an experimental field study, we document delayed effects of an introduced nest parasite, Philornis downsi, on reproduction of Galápagos mockingbirds (Mimus parvulus). Parasitism of first nests reduced both the number and size of chicks that parents hatched when they re-nested several weeks later. The delayed effect of P. downsi on future reproduction may have been mediated by behavioral shifts by the parents to avoid or resist parasitism. Our results demonstrate that effects of parasitism can persist even after immediate exposure ends. We draw attention to the potential implications that introduced parasites have for host reproductive strategies.
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Affiliation(s)
- Sabrina M McNew
- Department of Biology, University of Utah, Salt Lake City, UT, 84112-0840, USA.
- Fuller Evolutionary Biology Program, Cornell Lab of Ornithology, Ithaca, NY, 14850, USA.
| | - Graham B Goodman
- Department of Biology, University of Utah, Salt Lake City, UT, 84112-0840, USA
- Department of Biology, Hobart and William Smith Colleges, Geneva, NY, 14456, USA
| | - Janai Yépez R
- Charles Darwin Research Station, Santa Cruz Island, Galápagos, Ecuador
| | - Dale H Clayton
- Department of Biology, University of Utah, Salt Lake City, UT, 84112-0840, USA
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17
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Kleindorfer S, Custance G, Peters KJ, Sulloway FJ. Introduced parasite changes host phenotype, mating signal and hybridization risk: Philornis downsi effects on Darwin's finch song. Proc Biol Sci 2019; 286:20190461. [PMID: 31185871 DOI: 10.1098/rspb.2019.0461] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Introduced parasites that alter their host's mating signal can change the evolutionary trajectory of a species through sexual selection. Darwin's Camarhynchus finches are threatened by the introduced fly Philornis downsi that is thought to have accidentally arrived on the Galapagos Islands during the 1960s. The P. downsi larvae feed on the blood and tissue of developing finches, causing on average approximately 55% in-nest mortality and enlarged naris size in survivors. Here we test if enlarged naris size is associated with song characteristics and vocal deviation in the small tree finch ( Camarhynchus parvulus), the critically endangered medium tree finch ( C. pauper) and the recently observed hybrid tree finch group ( Camarhynchus hybrids). Male C. parvulus and C. pauper with enlarged naris size produced song with lower maximum frequency and greater vocal deviation, but there was no significant association in hybrids. Less vocal deviation predicted faster pairing success in both parental species. Finally, C. pauper males with normal naris size produced species-specific song, but male C. pauper with enlarged naris size had song that was indistinguishable from other tree finches. When parasites disrupt host mating signal, they may also facilitate hybridization. Here we show how parasite-induced naris enlargement affects vocal quality, resulting in blurred species mating signals.
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Affiliation(s)
- Sonia Kleindorfer
- 1 College of Science and Engineering, Flinders University , Adelaide 5001 , Australia.,2 Konrad Lorenz Research Station and Department of Behavioural Biology, University of Vienna , Vienna , Austria
| | - Georgina Custance
- 1 College of Science and Engineering, Flinders University , Adelaide 5001 , Australia
| | - Katharina J Peters
- 1 College of Science and Engineering, Flinders University , Adelaide 5001 , Australia
| | - Frank J Sulloway
- 3 Department of Psychology, University of California , 2121 Berkeley Way, Room 3302, 4125 Tolman Hall, Berkeley, CA 94720 , USA
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18
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McNew SM, Knutie SA, Goodman GB, Theodosopoulos A, Saulsberry A, Yépez R. J, Bush SE, Clayton DH. Annual environmental variation influences host tolerance to parasites. Proc Biol Sci 2019; 286:20190049. [PMID: 30963843 PMCID: PMC6408884 DOI: 10.1098/rspb.2019.0049] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 02/06/2019] [Indexed: 12/16/2022] Open
Abstract
When confronted with a parasite or pathogen, hosts can defend themselves by resisting or tolerating the attack. While resistance can be diminished when resources are limited, it is unclear how robust tolerance is to changes in environmental conditions. Here, we investigate the sensitivity of tolerance in a single host population living in a highly variable environment. We manipulated the abundance of an invasive parasitic fly, Philornis downsi, in nests of Galápagos mockingbirds ( Mimus parvulus) over four field seasons and measured host fitness in response to parasitism. Mockingbird tolerance to P. downsi varied significantly among years and decreased when rainfall was limited. Video observations indicate that parental provisioning of nestlings appears key to tolerance: in drought years, mockingbirds likely do not have sufficient resources to compensate for the effects of P. downsi. These results indicate that host tolerance is a labile trait and suggest that environmental variation plays a major role in mediating the consequences of host-parasite interactions.
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Affiliation(s)
- Sabrina M. McNew
- Department of Biology, University of Utah, Salt Lake City, UT 84112-0840, USA
| | - Sarah A. Knutie
- Department of Biology, University of Utah, Salt Lake City, UT 84112-0840, USA
| | - Graham B. Goodman
- Department of Biology, University of Utah, Salt Lake City, UT 84112-0840, USA
| | | | - Ashley Saulsberry
- Department of Biology, University of Utah, Salt Lake City, UT 84112-0840, USA
| | - Janai Yépez R.
- Charles Darwin Research Station, Santa Cruz Island, Galápagos, Ecuador
| | - Sarah E. Bush
- Department of Biology, University of Utah, Salt Lake City, UT 84112-0840, USA
| | - Dale H. Clayton
- Department of Biology, University of Utah, Salt Lake City, UT 84112-0840, USA
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19
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Knutie SA. Relationships among introduced parasites, host defenses, and gut microbiota of Galapagos birds. Ecosphere 2018. [DOI: 10.1002/ecs2.2286] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Affiliation(s)
- Sarah A. Knutie
- Department of Ecology and Evolutionary Biology University of Connecticut Storrs Connecticut 06269 USA
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20
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Clark TD, Kleindorfer S, Dudaniec RY. Baseline and stress-induced blood properties of male and female Darwin's small ground finch (Geospiza fuliginosa) of the Galapagos Islands. Gen Comp Endocrinol 2018; 259:199-206. [PMID: 29197554 DOI: 10.1016/j.ygcen.2017.11.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 11/01/2017] [Accepted: 11/28/2017] [Indexed: 10/18/2022]
Abstract
Birds are renowned for exhibiting marked sex-specific differences in activity levels and reproductive investment during the breeding season, potentially impacting circulating blood parameters associated with stress and energetics. Males of many passerines often do not incubate, but they experience direct exposure to intruder threat and exhibit aggressive behaviour during the nesting phase in order to defend territories against competing males and predators. Nesting females often have long bouts of inactivity during incubation, but they must remain vigilant of the risks posed by predators and conspecific intruders approaching the nest. Here, we use 33 free-living male (n = 16) and female (n = 17) Darwin's small ground finches (Geospiza fuliginosa) on Floreana Island (Galapagos Archipelago) to better understand how sex-specific roles during the reproductive period impact baseline and stress-induced levels of plasma corticosterone (CORT), blood glucose and haematocrit. Specifically, we hypothesise that males are characterised by higher baseline values given their direct and relatively frequent exposure to intruder threat, but that a standardised stress event (capture and holding) overrides any sex-specific differences. In contrast with expectations, baseline levels of all blood parameters were similar between sexes (13.4 ± 1.9 ng ml-1 for CORT, 13.7 ± 0.4 mmol l-1 for glucose, 58.3 ± 0.8% for haematocrit). Interestingly, females with higher body condition had lower baseline haematocrit. All blood parameters changed with time since capture (range 1.2-41.3 min) in both sexes, whereby CORT increased linearly, haematocrit decreased linearly, and glucose increased to a peak at ∼20 min post-capture and declined to baseline levels thereafter. Our results do not support the hypothesis that sex-specific roles during the reproductive period translate to differences in blood parameters associated with stress and energetics, but we found some evidence that blood oxygen transport capacity may decline as finches increase in body condition.
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Affiliation(s)
- Timothy D Clark
- Deakin University, School of Life and Environmental Sciences, Geelong 3216, Australia
| | - Sonia Kleindorfer
- College of Science and Engineering, Flinders University, Adelaide 5001, Australia.
| | - Rachael Y Dudaniec
- Department of Biological Sciences, Macquarie University, Sydney 2109, Australia
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21
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Stynoski JL, Stynoski PB, Noble VR. Empirical evidence for multiple costs of begging in poison frog tadpoles. ZOOL ANZ 2018. [DOI: 10.1016/j.jcz.2018.01.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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22
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McNew SM, Clayton DH. Alien Invasion: Biology of Philornis Flies Highlighting Philornis downsi, an Introduced Parasite of Galápagos Birds. ANNUAL REVIEW OF ENTOMOLOGY 2018; 63:369-387. [PMID: 29058976 DOI: 10.1146/annurev-ento-020117-043103] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The muscid genus Philornis comprises approximately 50 described species of flies, nearly all of which are obligate parasites of nestling birds. Philornis species are native to the Neotropics and widely distributed from Florida to Argentina. Most research on this group has focused on P. downsi, which was introduced to the Galápagos Islands in the late twentieth century. Although Philornis parasitism kills nestlings in several native host species, nowhere do the effects seem more severe than in P. downsi in the Galápagos. Here, we review studies of native and introduced Philornis in an attempt to identify factors that may influence virulence and consider implications for the conservation of hosts in the Galápagos.
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Affiliation(s)
- Sabrina M McNew
- Department of Biology, University of Utah, Salt Lake City, Utah 84112-0840, USA;
| | - Dale H Clayton
- Department of Biology, University of Utah, Salt Lake City, Utah 84112-0840, USA;
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23
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Fessl B, Heimpel GE, Causton CE. Invasion of an Avian Nest Parasite, Philornis downsi, to the Galapagos Islands: Colonization History, Adaptations to Novel Ecosystems, and Conservation Challenges. DISEASE ECOLOGY 2018. [DOI: 10.1007/978-3-319-65909-1_9] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Ben-Yosef M, Zaada DSY, Dudaniec RY, Pasternak Z, Jurkevitch E, Smith RJ, Causton CE, Lincango MP, Tobe SS, Mitchell JG, Kleindorfer S, Yuval B. Host-specific associations affect the microbiome ofPhilornis downsi, an introduced parasite to the Galápagos Islands. Mol Ecol 2017; 26:4644-4656. [DOI: 10.1111/mec.14219] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 05/25/2017] [Accepted: 06/13/2017] [Indexed: 01/08/2023]
Affiliation(s)
- Michael Ben-Yosef
- Department of Entomology; Faculty of Agriculture Food and Environment; The Hebrew University of Jerusalem; Rehovot Israel
| | - Doron S. Y. Zaada
- Department of Entomology; Faculty of Agriculture Food and Environment; The Hebrew University of Jerusalem; Rehovot Israel
| | - Rachael Y. Dudaniec
- Department of Biological Sciences; Macquarie University; Sydney NSW Australia
| | - Zohar Pasternak
- Department of Microbiology and Plant Pathology; Faculty of Agriculture Food and Environment; The Hebrew University of Jerusalem; Rehovot Israel
| | - Edouard Jurkevitch
- Department of Microbiology and Plant Pathology; Faculty of Agriculture Food and Environment; The Hebrew University of Jerusalem; Rehovot Israel
| | - Renee J. Smith
- School of Biological Sciences; Flinders University; Adelaide SA Australia
| | - Charlotte E. Causton
- Charles Darwin Foundation; Puerto Ayora Santa Cruz Island Galápagos Islands Ecuador
| | - Maria Piedad Lincango
- Charles Darwin Foundation; Puerto Ayora Santa Cruz Island Galápagos Islands Ecuador
- Facultad De Ciencias Agrícolas; Universidad Central Del Ecuador; Quito Pichincha Ecuador
| | - Shanan S. Tobe
- School of Biological Sciences; Flinders University; Adelaide SA Australia
- Department of Chemistry and Physics; Arcadia University; Glenside PA USA
| | - James G. Mitchell
- School of Biological Sciences; Flinders University; Adelaide SA Australia
| | - Sonia Kleindorfer
- School of Biological Sciences; Flinders University; Adelaide SA Australia
| | - Boaz Yuval
- Department of Entomology; Faculty of Agriculture Food and Environment; The Hebrew University of Jerusalem; Rehovot Israel
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25
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Kleindorfer S, Dudaniec RY. Host-parasite ecology, behavior and genetics: a review of the introduced fly parasite Philornis downsi and its Darwin’s finch hosts. BMC ZOOL 2016. [DOI: 10.1186/s40850-016-0003-9] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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26
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Kleindorfer S, Sulloway FJ. Naris deformation in Darwin’s finches: Experimental and historical evidence for a post-1960s arrival of the parasite Philornis downsi. Glob Ecol Conserv 2016. [DOI: 10.1016/j.gecco.2016.05.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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27
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Interactions between the Avian Parasite, Philornis downsi (Diptera: Muscidae) and the Galapagos Flycatcher, Myiarchus magnirostris Gould (Passeriformes: Tyrannidae). J Wildl Dis 2015; 51:907-10. [PMID: 26267462 DOI: 10.7589/2015-01-025] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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