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Guiry E, Kennedy JR, Malcom C, Miller M, Hall O, Buckley M, Szpak P. Archaeological evidence for long-term human impacts on sea turtle foraging behaviour. ROYAL SOCIETY OPEN SCIENCE 2024; 11:240120. [PMID: 39021767 PMCID: PMC11253035 DOI: 10.1098/rsos.240120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Revised: 03/18/2024] [Accepted: 06/05/2024] [Indexed: 07/20/2024]
Abstract
Early conservation efforts to prevent the loss of green sea turtles (Chelonia mydas) from the Caribbean Sea jumpstarted marine habitat and biodiversity protection. However, even there, limitations on historical observations of turtle ecology have hampered efforts to contextualize foraging behaviours for conservation management. We integrate isotopic and zooarchaeological evidence from green sea turtles harvested at the Miskito Cays (Nicaragua) to assess foraging behaviour before and after a step change in harvesting intensity. Highly structured isotopic evidence shows greater foraging adaptability in earlier populations. This provides a counterpoint to recent synthesis, suggesting the ecological non-exchangeability of sea turtles, which complicates conservation planning focused on genetic-stock-based repopulation. In contrast, our results suggest future populations would have a capacity for higher degrees of ecological exchangeability than current perspectives allow. This highlights a need to consider the kinds of longer term perspectives, such as those offered by archaeological materials, when planning for future sea turtle recovery.
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Affiliation(s)
- Eric Guiry
- Department of Anthropology, Trent University, 1600 West Bank Drive, Peterborough, OntarioK9L 0G2, Canada
- School of Archaeology and Ancient History, University of Leicester, Mayor’s Walk, LeicesterLE1 7RH, UK
| | - J. Ryan Kennedy
- Department of Anthropology, Indiana University Bloomington, 701 East Kirkwood Avenue, Bloomington, IN47405, USA
| | - Corey Malcom
- Florida Keys History Center, 700 Fleming Street, Key West, FL33040, USA
| | - Mariah Miller
- Department of Anthropology, Trent University, 1600 West Bank Drive, Peterborough, OntarioK9L 0G2, Canada
| | - Olivia Hall
- Department of Anthropology, Trent University, 1600 West Bank Drive, Peterborough, OntarioK9L 0G2, Canada
| | - Michael Buckley
- School of Natural Sciences, Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, ManchesterM17 DN, UK
| | - Paul Szpak
- Department of Anthropology, Trent University, 1600 West Bank Drive, Peterborough, OntarioK9L 0G2, Canada
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2
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Sanchez CL, Casale P, Bunbury N, A'Bear L, Banane V, Benstrong F, Bielsa M, Jones CW, Koester A, Murasko S, van Rooyen MC, Fleischer-Dogley F, Ceriani SA. Fine-scale foraging ecology and habitat use of sympatric green and hawksbill turtles in the Western Indian ocean. MARINE ENVIRONMENTAL RESEARCH 2024; 198:106529. [PMID: 38688109 DOI: 10.1016/j.marenvres.2024.106529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 04/01/2024] [Accepted: 04/26/2024] [Indexed: 05/02/2024]
Abstract
Using stable isotope analysis of carbon and nitrogen of turtle tissues and putative prey items, we investigated the diet of immature green turtles and hawksbill turtles foraging in the lagoon of Aldabra Atoll, a relatively undisturbed atoll in the southern Seychelles. Aldabra offers a unique environment for understanding sea turtle ecology. Green turtles mostly consumed seagrass and brown algae while hawksbill turtles mainly consumed mangroves and invertebrates. Green turtles showed a dietary shift with size (a proxy for age). There was minimal niche overlap between species and evidence of small-scale foraging site fidelity with turtle tissue reflecting site-specific prey. This highlights the ecological importance of seagrass and mangrove habitats and suggests that turtles play a role in controlling algal biomass at Aldabra. This study is the first to closely examine the foraging ecology of these sympatric turtle species in the Western Indian Ocean, a globally important region for both species.
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Affiliation(s)
- Cheryl L Sanchez
- Department of Biology, University of Pisa, Via A. Volta 6, 56126 Pisa, Italy; Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, Saint Petersburg, FL, USA; Seychelles Islands Foundation, Mahé, P.O. Box 853, Victoria, Seychelles
| | - Paolo Casale
- Department of Biology, University of Pisa, Via A. Volta 6, 56126 Pisa, Italy.
| | - Nancy Bunbury
- Seychelles Islands Foundation, Mahé, P.O. Box 853, Victoria, Seychelles; Centre for Ecology and Conservation, University of Exeter, Cornwall Campus, Penryn TR10 9FE, UK
| | - Luke A'Bear
- Seychelles Islands Foundation, Mahé, P.O. Box 853, Victoria, Seychelles
| | - Veronique Banane
- Seychelles Islands Foundation, Mahé, P.O. Box 853, Victoria, Seychelles
| | - Frances Benstrong
- Seychelles Islands Foundation, Mahé, P.O. Box 853, Victoria, Seychelles
| | - Maria Bielsa
- Seychelles Islands Foundation, Mahé, P.O. Box 853, Victoria, Seychelles
| | | | - Anna Koester
- Seychelles Islands Foundation, Mahé, P.O. Box 853, Victoria, Seychelles
| | - Susan Murasko
- Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, Saint Petersburg, FL, USA
| | | | | | - Simona A Ceriani
- Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, Saint Petersburg, FL, USA
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3
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Bezerra MF, Barrios-Rodriguez CA, Rezende CE, López-Castro MC, Lacerda LD. Trophic ecology of sympatric sea turtles in the tropical Atlantic coast of Brazil. MARINE ENVIRONMENTAL RESEARCH 2024; 196:106406. [PMID: 38377937 DOI: 10.1016/j.marenvres.2024.106406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 02/09/2024] [Accepted: 02/12/2024] [Indexed: 02/22/2024]
Abstract
The Tropical Atlantic coast of Brazil is a hotspot area for multiple sea turtle species at all life stages. The multiple nearshore reefs and beaches, oceanic islands, and the only atoll in the south Atlantic Ocean, are suitable for year-round foraging, migration corridors, and nesting activities of five sea turtle species. Still, relatively few studies have assessed trophic niche among sympatric sea turtles which can provide a better understanding of how closely related species compete/partition the available resources. Using multiple biogeochemical tracers (i.e., nitrogen (δ15N) and carbon (δ13C) stable isotopes, and mercury (Hg)), we disentangled the trophic niches of four sea turtle species - the green turtle (Chelonia mydas), the loggerhead turtle (Caretta), the hawksbill turtle (Eretmochelys imbricata), and the olive ridley turtle (Lepidochelys olivacea) - co-occurring in nesting and foraging habitats along the northeastern coast of Brazil. We found interspecific differences in isotopic and contamination niches, as well as intraspecific niche variation associated with life stage. Differences in the estimation niche models associated to life-stage in C. caretta support the notion of ontogenetic shift in habitat and diet composition previously reported for this species. Oceanic habitat signatures were observed in juvenile green turtles and adult olive turtles, while nearshore habitat signatures were observed in adult hawksbill turtles.
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Affiliation(s)
- Moises F Bezerra
- Universidade Federal Do Ceará - Instituto de Ciências Do Mar (LABOMAR-UFC). Fortaleza, Ceará, Brazil.
| | - Cesar A Barrios-Rodriguez
- Universidade Federal Do Ceará - Instituto de Ciências Do Mar (LABOMAR-UFC). Fortaleza, Ceará, Brazil
| | - Carlos E Rezende
- Centro de Biociências e Biotecnologia, Universidade Estadual Do Norte Fluminense Darcy Ribeiro Campos Dos Goytacazes, Rio de Janeiro, Brazil
| | | | - Luiz D Lacerda
- Universidade Federal Do Ceará - Instituto de Ciências Do Mar (LABOMAR-UFC). Fortaleza, Ceará, Brazil
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4
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Verzele P, Rodriguez CB, Bezerra MF, Lacerda LD. Regional differences in Hg contents in the liver and muscle of the green turtle (Chelonia mydas) from three foraging grounds in Northeast Brazil. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:3917-3925. [PMID: 38095795 DOI: 10.1007/s11356-023-31407-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 12/03/2023] [Indexed: 01/19/2024]
Abstract
Mercury (Hg) is a highly toxic pollutant that endangers several marine animals, including green sea turtles (Chelonia mydas), particularly in their foraging grounds along Brazilian coastal waters. Environmental Hg levels differ along this extensive littoral, rendering mandatory Hg long-term assessments of the different Hg fate in different sectors of the Brazilian coast. This study quantifies total Hg concentrations in the liver and muscle of green sea turtle populations from three foraging coastal regions in northeastern Brazil and analyzes Hg concentration differences given the locality and size of 61 juvenile individuals sampled. The results showed wide variations in Hg concentrations in the liver (81-3135 ng g-1) and muscle (10.1-8569 ng g-1). There was no significant correlation between animal size and Hg concentrations. Also, no difference was found among areas, reflecting the opportunistic feeding habit of juveniles of this species. This suggests that, in the case of green turtles, the ontogenetic change of diet plays an important role in influencing Hg concentrations found in this species.
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Affiliation(s)
- Paul Verzele
- Laboratório de Biogeoquímica Costeira, Instituto de Ciências Do Mar, Universidade Federal Do Ceará, Av. Abolição, Fortaleza, Ceará, 3207, 60165-081, Brazil.
- CNRS/INSU, IRD, MIO UM, Université de Toulon, La Garde, France.
| | - César B Rodriguez
- Laboratório de Biogeoquímica Costeira, Instituto de Ciências Do Mar, Universidade Federal Do Ceará, Av. Abolição, Fortaleza, Ceará, 3207, 60165-081, Brazil
| | - Moisés F Bezerra
- Laboratório de Biogeoquímica Costeira, Instituto de Ciências Do Mar, Universidade Federal Do Ceará, Av. Abolição, Fortaleza, Ceará, 3207, 60165-081, Brazil
| | - Luiz D Lacerda
- Laboratório de Biogeoquímica Costeira, Instituto de Ciências Do Mar, Universidade Federal Do Ceará, Av. Abolição, Fortaleza, Ceará, 3207, 60165-081, Brazil
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Wilkinson A, Ariel E, van de Merwe J, Brodie J. Green Turtle (Chelonia mydas) Blood and Scute Trace Element Concentrations in the Northern Great Barrier Reef. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2023; 42:2375-2388. [PMID: 37477460 DOI: 10.1002/etc.5718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/08/2023] [Accepted: 07/13/2023] [Indexed: 07/22/2023]
Abstract
Marine turtles face numerous anthropogenic threats, including that of chemical contaminant exposure. The ecotoxicological impact of toxic metals is a global issue facing Chelonia mydas in coastal sites. Local investigation of C. mydas short-term blood metal profiles is an emerging field, while little research has been conducted on scute metal loads as potential indicators of long-term exposure. The aim of the present study was to investigate and describe C. mydas blood and scute metal profiles in coastal and offshore populations of the Great Barrier Reef. This was achieved by analyzing blood and scute material sampled from local C. mydas populations in five field sites, for a suite of ecologically relevant metals. By applying principal component analysis and comparing coastal sample data with those of reference intervals derived from the control site, insight was gleaned on local metal profiles of each population. Blood metal concentrations in turtles from coastal sites were typically elevated when compared with levels recorded in the offshore control population (Howick Island Group). Scute metal profiles were similar in Cockle Bay, Upstart Bay, and Edgecumbe Bay, all of which were distinct from that of Toolakea. Some elements were reported at similar concentrations in blood and scutes, but most were higher in scute samples, indicative of temporal accumulation. Coastal C. mydas populations may be at risk of toxic effects from metals such as Co, which was consistently found to be at concentrations magnitudes above region-specific reference intervals. Environ Toxicol Chem 2023;42:2375-2388. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
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Affiliation(s)
- Adam Wilkinson
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland, Australia
| | - Ellen Ariel
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland, Australia
| | - Jason van de Merwe
- Australian Rivers Institute and School of Environment and Science, Griffith University, Gold Coast, Queensland, Australia
| | - Jon Brodie
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, Australia
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6
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Silver-Gorges I, Ceriani SA, Fuentes MMPB. Fine-scale intraspecific niche partitioning in a highly mobile, marine megafauna species: implications for ecology and conservation. ROYAL SOCIETY OPEN SCIENCE 2023; 10:221529. [PMID: 37388320 PMCID: PMC10300683 DOI: 10.1098/rsos.221529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 06/09/2023] [Indexed: 07/01/2023]
Abstract
A species may partition its realized ecological niche along bionomic and scenopoetic axes due to intraspecific competition for limited resources. How partitioning manifests depends on resource needs and availability by and for the partitioning groups. Here we demonstrate the utility of analysing short- and long-term stable carbon and nitrogen isotope ratios from imperiled marine megafauna to characterize realized niche partitioning in these species. We captured 113 loggerhead sea turtles (Caretta caretta) at a high-use area in the eastern Big Bend, Florida, between 2016 and 2022, comprising 53 subadults, 10 adult males and 50 adult females. We calculated trophic niche metrics using established and novel methods, and constructed Bayesian ellipses and hulls, to characterize loggerhead isotopic niches. These analyses indicated that loggerheads partition their realized ecological niche by lifestage, potentially along both bionomic (e.g. trophic) and/or scenopoetic (e.g. habitat, latitude or longitude) axes, and display different characteristics of resource use within their niches. Analysis of stable isotopes from tissues with different turnover rates enabled this first characterization of intraspecific niche partitioning between and within neritic lifestages in loggerhead turtles, which has direct implications for ongoing research and conservation efforts for this and other imperiled marine species.
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Affiliation(s)
- Ian Silver-Gorges
- Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, FL 32304, USA
| | - Simona A. Ceriani
- Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, St. Petersburg, FL 33701, USA
| | - Mariana M. P. B. Fuentes
- Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, FL 32304, USA
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7
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Barrios-Rodríguez CA, de Lacerda LD, Fernandes-Bezerra M. A Pilot Study of Mercury Distribution in the Carapace of Four Species of Sea Turtles from Northeastern Brazil. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2023; 110:99. [PMID: 37243788 DOI: 10.1007/s00128-023-03745-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 05/19/2023] [Indexed: 05/29/2023]
Abstract
Scutes present very complex morphologies with different growth rates at different areas of the carapace that can change the accumulation process of essential and non-essential metals. To infer the effects of morphology and growth on Hg concentrations in scutes, we mapped them in the carapace of one individual of four species of sea turtles sampled along the Brazilian coast. The results showed that Hg concentrations were higher in the vertebral scutes of Chelonia mydas and Eretmochelys imbricata suggesting variation in growth rates of different carapace areas since the vertebral area is the first to develop prior to costal areas. Caretta caretta and Lepidochelys olivacea did not show differences between carapace areas. The preliminary data from this pilot study indicate that vertebral scutes may be suitable for monitoring Hg in C. mydas and E. imbricata, since they reflect longer exposure period. A species-to-species comparison of Hg concentrations is not possible due to the small number of sampled individuals, nevertheless, E. imbricata showed remarkably lower Hg concentrations compared to the other three species. Further studies are required for all four species, with a larger number of individuals, preferentially of varying life stages, due to the unknown effects of different diets, Hg exposure, and migration histories.
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Affiliation(s)
- César Augusto Barrios-Rodríguez
- Laboratório de Biogeoquímica Costeira, Instituto de Ciências do Mar, Universidade Federal do Ceará, Av. Abolição, 3207, Fortaleza, Ceará, 60165-081, Brasil.
| | - Luiz Drude de Lacerda
- Laboratório de Biogeoquímica Costeira, Instituto de Ciências do Mar, Universidade Federal do Ceará, Av. Abolição, 3207, Fortaleza, Ceará, 60165-081, Brasil
| | - Moises Fernandes-Bezerra
- Laboratório de Biogeoquímica Costeira, Instituto de Ciências do Mar, Universidade Federal do Ceará, Av. Abolição, 3207, Fortaleza, Ceará, 60165-081, Brasil
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Teixeira CR, Botta S, Cremer MJ, Marcondes MCC, Pereira LB, Newsome SD, Jorge FGD, Simões-Lopes PC. Ecologically driven differences in individual diet specialization across three populations of Guiana dolphin. Oecologia 2023; 201:397-408. [PMID: 36650314 DOI: 10.1007/s00442-022-05312-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 12/29/2022] [Indexed: 01/19/2023]
Abstract
Populations usually considered foraging generalists may include specialized individuals that feed on a restricted subset of the prey spectrum consumed by the population. By analyzing the time series of δ13C and δ15N values in sequential growth layer groups within tooth dentin, we measured population- and individual-level variation in resource use of three populations of Guiana dolphins (Sotalia guianensis)-Caravelas River, Babitonga Bay, and Norte Bay-along a latitudinal gradient in the southwestern Atlantic Ocean. We show that the Guiana dolphin at Caravelas River is a generalist population consisting of individual dietary specialists, likely due to the absence of other resident dolphin populations thus allowing individuals to target prey across a wide range of habitats. The Babitonga Bay population is also composed of individual specialists potentially due to the selective foraging behavior of some individuals on high-quality prey sources within and near the bay. In contrast, the Norte Bay population comprises individual generalists, which likely reflects its distinctive cohesive social organization, coexistence with two other dolphin species, and an opportunistic foraging strategy in response to resource fluctuations inherent to the southern limit of the species distribution. Although the Guiana dolphin is generally considered to be a dietary generalist at the population level, our findings reveal that the total niche width of populations and the degree of individual diet specialization are highly context dependent, suggesting dietary plasticity that may be related to a latitudinal gradient in resource availability and environmental conditions.
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Affiliation(s)
- Clarissa R Teixeira
- Laboratório de Mamíferos Aquáticos (LAMAQ), Departamento de Ecologia e Zoologia, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil. .,Department of Fisheries, Wildlife, and Conservation Sciences, Marine Mammal Institute, Oregon State University, Newport, OR, USA.
| | - Silvina Botta
- Laboratório de Ecologia e Conservação da Megafauna Marinha (ECOMEGA), Instituto de Oceanografia, Universidade Federal do Rio Grande, Rio Grande, Brazil
| | - Marta J Cremer
- Laboratório de Ecologia e Conservação de Tetrápodes Marinhos e Costeiros (TetraMar), Unidade São Francisco do Sul, Universidade da Região de Joinville, São Francisco do Sul, Santa Catarina, Brazil
| | | | - Luiza B Pereira
- Laboratório de Mamíferos Aquáticos (LAMAQ), Departamento de Ecologia e Zoologia, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Seth D Newsome
- Department of Biology, University of New Mexico, Albuquerque, NM, USA
| | - Fábio G Daura Jorge
- Laboratório de Mamíferos Aquáticos (LAMAQ), Departamento de Ecologia e Zoologia, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Paulo C Simões-Lopes
- Laboratório de Mamíferos Aquáticos (LAMAQ), Departamento de Ecologia e Zoologia, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil
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Walker RH, Hutchinson MC, Potter AB, Becker JA, Long RA, Pringle RM. Mechanisms of individual variation in large herbivore diets: Roles of spatial heterogeneity and state-dependent foraging. Ecology 2023; 104:e3921. [PMID: 36415899 PMCID: PMC10078531 DOI: 10.1002/ecy.3921] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 10/05/2022] [Accepted: 10/06/2022] [Indexed: 11/24/2022]
Abstract
Many populations of consumers consist of relatively specialized individuals that eat only a subset of the foods consumed by the population at large. Although the ecological significance of individual-level diet variation is recognized, such variation is difficult to document, and its underlying mechanisms are poorly understood. Optimal foraging theory provides a useful framework for predicting how individuals might select different diets, positing that animals balance the "opportunity cost" of stopping to eat an available food item against the cost of searching for something more nutritious; diet composition should be contingent on the distribution of food, and individual foragers should be more selective when they have greater energy reserves to invest in searching for high-quality foods. We tested these predicted mechanisms of individual niche differentiation by quantifying environmental (resource heterogeneity) and organismal (nutritional condition) determinants of diet in a widespread browsing antelope (bushbuck, Tragelaphus sylvaticus) in an African floodplain-savanna ecosystem. We quantified individuals' realized dietary niches (taxonomic richness and composition) using DNA metabarcoding of fecal samples collected repeatedly from 15 GPS-collared animals (range 6-14 samples per individual, median 12). Bushbuck diets were structured by spatial heterogeneity and constrained by individual condition. We observed significant individual-level partitioning of food plants by bushbuck both within and between two adjacent habitat types (floodplain and woodland). Individuals with home ranges that were closer together and/or had similar vegetation structure (measured using LiDAR) ate more similar diets, supporting the prediction that heterogeneous resource distribution promotes individual differentiation. Individuals in good nutritional condition had significantly narrower diets (fewer plant taxa), searched their home ranges more intensively (intensity-of-use index), and had higher-quality diets (percent digestible protein) than those in poor condition, supporting the prediction that animals with greater endogenous reserves have narrower realized niches because they can invest more time in searching for nutritious foods. Our results support predictions from optimal foraging theory about the energetic basis of individual-level dietary variation and provide a potentially generalizable framework for understanding how individuals' realized niche width is governed by animal behavior and physiology in heterogeneous landscapes.
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Affiliation(s)
- Reena H Walker
- Department of Fish and Wildlife Sciences, University of Idaho, Moscow, Idaho, USA
| | - Matthew C Hutchinson
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey, USA
| | - Arjun B Potter
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey, USA
| | - Justine A Becker
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey, USA.,Department of Zoology and Physiology, University of Wyoming, Laramie, Wyoming, USA
| | - Ryan A Long
- Department of Fish and Wildlife Sciences, University of Idaho, Moscow, Idaho, USA
| | - Robert M Pringle
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey, USA
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10
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Jarcovis RDLM, Taniguchi S, da Silva J, Lourenço RA. Persistent organic pollutants and stable isotopes in the liver of Chelonia mydas stranded on the southeastern Brazilian coast. MARINE POLLUTION BULLETIN 2021; 173:113075. [PMID: 34741921 DOI: 10.1016/j.marpolbul.2021.113075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 10/16/2021] [Accepted: 10/17/2021] [Indexed: 06/13/2023]
Abstract
Among the various pollutants released into the environment, there are persistent organic pollutants (POPs). Chelonia mydas are one of the species that can be exposed to these pollutants and it is classified in the IUCN Red List as "endangered". The present study evaluated the occurrence of POPs in 49liver tissue samples of C. mydas juveniles collected on the southeastern Brazilian coast. Furthermore, the concentrations were correlated with carbon and nitrogen isotopic ratio, biometrics, and ecological factors. The main POPs found were ƴ-HCH and PCBs. Overall, the concentrations found were low and there were no significant correlations among POPs, isotopic ratios, size and weight, which may be related to the fact that the studied individuals are juveniles and occupy similar trophic positions despite the individual variations found. Despite the low concentrations, the presence of POPs, mainly PCBs, in the sea turtles' liver indicates their exposure to these compounds.
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Affiliation(s)
- Raphael De Lucca Marcello Jarcovis
- Instituto Oceanográfico da Universidade de São Paulo (IO-USP), Praça do Oceanográfico, 191, Cidade Universitária, São Paulo 05508-120, Brazil.
| | - Satie Taniguchi
- Instituto Oceanográfico da Universidade de São Paulo (IO-USP), Praça do Oceanográfico, 191, Cidade Universitária, São Paulo 05508-120, Brazil
| | - Josilene da Silva
- Instituto Oceanográfico da Universidade de São Paulo (IO-USP), Praça do Oceanográfico, 191, Cidade Universitária, São Paulo 05508-120, Brazil
| | - Rafael André Lourenço
- Instituto Oceanográfico da Universidade de São Paulo (IO-USP), Praça do Oceanográfico, 191, Cidade Universitária, São Paulo 05508-120, Brazil
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11
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Dogruer G, Kramer NI, Schaap IL, Hollert H, Gaus C, van de Merwe JP. An integrative approach to define chemical exposure threshold limits for endangered sea turtles. JOURNAL OF HAZARDOUS MATERIALS 2021; 420:126512. [PMID: 34284283 DOI: 10.1016/j.jhazmat.2021.126512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 06/04/2021] [Accepted: 06/24/2021] [Indexed: 06/13/2023]
Abstract
Environmental contaminants pose serious health threats to marine megafauna species, yet methods defining exposure threshold limits are lacking. Here, a three-pillar chemical risk assessment framework is presented based on (1) species- and chemical-specific lifetime bioaccumulation modelling, (2) non-destructive in vitro and in vivo toxicity threshold assessment, and (3) chemical risk quantification. We used the effects of cadmium (Cd) in green sea turtles (Chelonia mydas) as a proof of concept to evaluate the quantitative mechanistic modelling approach. A physiologically-based kinetic (PBK) model simulated Cd tissue concentrations (liver, kidney, muscle, fat, brain, scute, and 'rest of the body') in C.mydas. The validated PBK model then translated species-specific in vitro results to in vivo effects. The results showed that the resilience of C.mydas towards Cd kidney toxicity is age-dependent and differs with changing physiology and feeding ecology. Using the model in reverse mode, a steady-state exposure threshold of 0.1 µg/g dry weight Cd in forage was derived and compared to real-world exposure scenarios. Three out of the four globally distinct C.mydas populations assessed are exposed to Cd levels above this threshold limit. This approach can be adapted to other marine species and chemicals to prioritize measures for managing potentially harmful chemical exposures.
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Affiliation(s)
- Gulsah Dogruer
- Australian Rivers Institute, School of Environment and Science, Griffith University, Gold Coast, Australia; Institute for Risk Assessment Sciences, The School of Veterinary Medicine, Utrecht University, Utrecht, Netherlands.
| | - Nynke I Kramer
- Institute for Risk Assessment Sciences, The School of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Iris L Schaap
- Institute for Risk Assessment Sciences, The School of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Henner Hollert
- Department Evolutionary Ecology & Environmental Toxicology, Institute of Ecology, Evolution and Diversity, Goethe University Frankfurt, Frankfurt, Germany
| | - Caroline Gaus
- Queensland Alliance for Environmental Health Science, The University of Queensland, Brisbane, Australia
| | - Jason P van de Merwe
- Australian Rivers Institute, School of Environment and Science, Griffith University, Gold Coast, Australia
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12
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Ramirez MD, Besser AC, Newsome SD, McMahon KW. Meta‐analysis of primary producer amino acid δ
15
N values and their influence on trophic position estimation. Methods Ecol Evol 2021. [DOI: 10.1111/2041-210x.13678] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Matthew D. Ramirez
- Graduate School of Oceanography University of Rhode Island Narragansett RI USA
| | - Alexi C. Besser
- Department of Biology University of New Mexico Albuquerque NM USA
| | - Seth D. Newsome
- Department of Biology University of New Mexico Albuquerque NM USA
| | - Kelton W. McMahon
- Graduate School of Oceanography University of Rhode Island Narragansett RI USA
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13
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Seminoff JA, Komoroske LM, Amorocho D, Arauz R, Chacón‐Chaverrí D, Paz N, Dutton PH, Donoso M, Heidemeyer M, Hoeffer G, Todd Jones T, Kelez S, Lemons GE, Rguez‐Baron JM, Sampson L, Santos Baca L, Steiner T, Vejar Rubio M, Zárate P, Zavala‐Norzagaray A, Popp BN. Large‐scale patterns of green turtle trophic ecology in the eastern Pacific Ocean. Ecosphere 2021. [DOI: 10.1002/ecs2.3479] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Jeffrey A. Seminoff
- NOAA‐National Marine Fisheries Service Southwest Fisheries Science Center La Jolla California USA
| | - Lisa M. Komoroske
- NOAA‐National Marine Fisheries Service Southwest Fisheries Science Center La Jolla California USA
- Department of Environmental Conservation University of Massachusetts Amherst Amherst Massachusetts USA
| | - Diego Amorocho
- Centro De Investigacion Para El Manejo Ambiental y El Desarrollo Cali Colombia
| | - Randall Arauz
- Fins Attached Marine Research and Conservation Colorado Springs Colorado USA
| | | | - Nelly Paz
- Areas Costeras y Recursos Marinos Pisco Perú
| | - Peter H. Dutton
- NOAA‐National Marine Fisheries Service Southwest Fisheries Science Center La Jolla California USA
| | | | - Maike Heidemeyer
- Escuela de Biología Centro de Investigación en Biología Celular y Molecular Centro de Investigación en Ciencas del Mar y Limnología (CIMAR) Universidad de Costa Rica San Pedro Costa Rica
| | | | - T. Todd Jones
- Pacific Islands Fisheries Science Center NOAA‐National Marine Fisheries Service Honolulu Hawaii USA
| | | | - Garrett E. Lemons
- NOAA‐National Marine Fisheries Service Southwest Fisheries Science Center La Jolla California USA
| | - Juan M. Rguez‐Baron
- Universidad Autónoma de Baja California Sur La Paz Baja California Sur México
| | - Laura Sampson
- Department of Biology Universidad del Valle Cali Colombia
| | - Lucía Santos Baca
- Department of Natural Resources Centro de Investigaciones Biológicas del Noroeste La Paz México
| | - Todd Steiner
- Turtle Island Restoration Network Forest Knolls California USA
- MigraMar Forest Knolls California USA
| | - Maria Vejar Rubio
- Instituto Politécnico Nacional CIIDIR Unidad Sinaloa Guasave Sinaloa México
| | - Patricia Zárate
- MigraMar Forest Knolls California USA
- Department of Biology University of Florida Gainesville Florida USA
| | | | - Brian N. Popp
- Department of Earth Sciences University of Hawai'i at Manoa Honolulu Hawaii USA
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14
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Filippos LS, Taniguchi S, Baldassin P, Pires T, Montone RC. Persistent organic pollutants in plasma and stable isotopes in red blood cells of Caretta caretta, Chelonia mydas and Lepidochelys olivacea sea turtles that nest in Brazil. MARINE POLLUTION BULLETIN 2021; 167:112283. [PMID: 33799149 DOI: 10.1016/j.marpolbul.2021.112283] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 03/11/2021] [Accepted: 03/13/2021] [Indexed: 06/12/2023]
Abstract
Studies of persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs), in sea turtles are reported, but there are still spatial data gaps worldwide. POP contamination of live female blood plasma from Caretta caretta (n = 28), Chelonia mydas (n = 31) and Lepidochelys olivacea (n = 19), which nest in Brazil and feed along the South Atlantic Ocean, was investigated. Carbon and nitrogen stable isotopes from red blood cells (RBC) were also evaluated to obtain information about trophic ecology. C. caretta had the highest POP concentrations, followed by L. olivacea and C. mydas. PCBs predominated in all species, and the major OCPs were the DDTs (dichlorodiphenyltrichloroethane and derivatives) and Lindane. POPs and stable isotopes revealed intra- and interspecific variations, which reflect the high plasticity in the use of habitat and food resources, making individuals within the same population susceptible to different exposures to pollutants.
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Affiliation(s)
- Luciana S Filippos
- Universidade de São Paulo, Instituto Oceanográfico, Laboratório de Química Orgânica Marinha, Praça do Oceanográfico 191, São Paulo, SP 05508-120, Brazil.
| | - Satie Taniguchi
- Universidade de São Paulo, Instituto Oceanográfico, Laboratório de Química Orgânica Marinha, Praça do Oceanográfico 191, São Paulo, SP 05508-120, Brazil
| | - Paula Baldassin
- Instituto BW, Professora Suely Brasil Flores, 88, CEP 28.970-000, Praia Seca, Araruama, RJ, Brazil
| | - Thaís Pires
- Fundação Projeto Tamar, Rua Rubens Guelli 134/307, Itaigara, Salvador, CEP: 41815-135, Bahia, Brazil
| | - Rosalinda C Montone
- Universidade de São Paulo, Instituto Oceanográfico, Laboratório de Química Orgânica Marinha, Praça do Oceanográfico 191, São Paulo, SP 05508-120, Brazil
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15
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Páez-Rosas D, Salinas-de-León P, Proaño A, Vaca-Pita L, Suarez-Moncada J. Multi-tissue stable isotope analyses reveal temporal changes in the feeding patterns of green turtles in the Galapagos Marine Reserve. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2021; 335:319-328. [PMID: 33481356 DOI: 10.1002/jez.2444] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 12/24/2020] [Accepted: 12/26/2020] [Indexed: 11/07/2022]
Abstract
Knowledge of feeding patterns of highly migratory species is critical for understanding their habitat use and informing the management of their populations. The Galapagos Islands are one of the most important nesting and feeding areas for green turtles (Chelonia mydas) across the tropical eastern Pacific, yet little is known about the feeding patterns of this species. The isotopic composition of different tissues has been used to gain insight into the trophic dynamics of mobile aquatic consumers whose trophic behavior is difficult to directly measure. To elucidate the temporal feeding patterns and isotopic niche sizes of Galapagos green turtles, stable isotope analyses were performed on multiple tissues (skin and carapace) collected at the two most important nesting areas in the archipelago: Bachas and Quinta Playa. The δ13 C and δ15 N signatures on the skin and carapace samples from 56 adult females revealed significant differences between tissues (p = .001 and p = .021, respectively) and nesting areas (p = .011 and p = .003, respectively). These differences suggest a shift from oceanic feeding grounds to neritic habitats before nesting. The carapace isotope values indicated an offshore feeding strategy and a greater isotopic niche (SEAc = 1.91‰2 ), whereas the skin isotope values represented an inshore feeding strategy with a narrower niche (SEAc = 1.37‰2 ), likely related to the consumption of specific coastal prey. Our results suggest that Galapagos green turtles feed across different habitats, and this information can be applied to improve the management of this endangered species.
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Affiliation(s)
- Diego Páez-Rosas
- Galapagos Science Center, Universidad San Francisco de Quito, Isla San Cristóbal, Islas Galápagos, Ecuador
| | - Pelayo Salinas-de-León
- Fundación Charles Darwin, Charles Darwin Research Station, Isla Santa Cruz, Islas Galápagos, Ecuador.,Pristine Seas, National Geographic Society, Washington, District of Columbia, USA
| | - Alberto Proaño
- Departamento de Ecosistemas Marinos, Dirección Parque Nacional Galápagos, Isla Santa Cruz, Islas Galápagos, Ecuador
| | - Leandro Vaca-Pita
- Galapagos Science Center, Universidad San Francisco de Quito, Isla San Cristóbal, Islas Galápagos, Ecuador
| | - Jenifer Suarez-Moncada
- Departamento de Ecosistemas Marinos, Dirección Parque Nacional Galápagos, Isla Santa Cruz, Islas Galápagos, Ecuador
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16
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Agostinho KFF, Monteiro LR, Beneditto APMD. Individual niche trajectories in nesting green turtles on Rocas Atoll, Brazil: an isotopic tool to assess diet shifts over time. BIOTA NEOTROPICA 2021. [DOI: 10.1590/1676-0611-bn-2020-1099] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Abstract In this study, multi-tissue (yolk and carapace) stable isotope analysis was used to assess individual isotopic niche trajectories of nesting green turtles on Rocas Atoll, off northeastern Brazil, and to reveal a diet shift in the temporal dimension. The diet trajectories of individual green turtles were highly directional, with a stronger component towards decreasing values of δ15N from carapace to yolk. When the green turtles are in their foraging sites (temporal window measured by the yolk samples), they are more herbivores. Conversely, in a broader temporal window, the green turtles demonstrate a carnivore-omnivore strategy, such as represented by heavier δ15N values in the carapace. This finding confirms a temporal diet shift. This is the first study that applies trophic niche trajectories for sea turtles, adding a new isotopic tool to understand the trophic ecology of these migrant animals.
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17
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Agostinho KFF, Pestana IA, Carvalho CEVD, Di Beneditto APM. Trace elements and stable isotopes in egg yolk of green turtles on Rocas Atoll, Brazil. MARINE POLLUTION BULLETIN 2021; 162:111821. [PMID: 33162056 DOI: 10.1016/j.marpolbul.2020.111821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 10/26/2020] [Accepted: 10/28/2020] [Indexed: 06/11/2023]
Abstract
This study analyzed trace elements (As, Ba, Cd, Cu, Fe, Mn, Pb, Zn) and stable isotopes of carbon and nitrogen in egg yolk samples of female green turtles that nested in Rocas Atoll, Brazil, in 2017 and 2018. The trace elements concentration varied between years, with higher concentrations in 2017, suggesting that the nesting groups come from different foraging sites. The isotopic data indicated high overlap between years (73%), leading to an ambiguous interpretation on the turtles' foraging site. The Normalized Total Load presented a low association (0.01 < R2 < 0.41) with the stable isotopes. The Normalized Total Load that represents the trace element load in egg yolk is a holistic approach that can be applied elsewhere to predict ecotoxicology pathways in any animal species. We recommend a continuous monitoring to verify how the trace elements load behave in the nesting green turtles on Rocas Atoll.
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Affiliation(s)
- Karoline Fernanda Ferreira Agostinho
- Universidade Estadual do Norte Fluminense Darcy Ribeiro, CBB, Laboratório de Ciências Ambientais, Av. Alberto Lamego 2000, Campos dos Goytacazes 28013-602, RJ, Parque Califórnia, Brazil.
| | - Inácio Abreu Pestana
- Universidade Estadual do Norte Fluminense Darcy Ribeiro, CBB, Laboratório de Ciências Ambientais, Av. Alberto Lamego 2000, Campos dos Goytacazes 28013-602, RJ, Parque Califórnia, Brazil.
| | - Carlos Eduardo Veiga de Carvalho
- Universidade Estadual do Norte Fluminense Darcy Ribeiro, CBB, Laboratório de Ciências Ambientais, Av. Alberto Lamego 2000, Campos dos Goytacazes 28013-602, RJ, Parque Califórnia, Brazil
| | - Ana Paula Madeira Di Beneditto
- Universidade Estadual do Norte Fluminense Darcy Ribeiro, CBB, Laboratório de Ciências Ambientais, Av. Alberto Lamego 2000, Campos dos Goytacazes 28013-602, RJ, Parque Califórnia, Brazil.
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18
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Zango L, Navarro-Herrero L, García-Vendrell M, Safi K, González-Solís J. Niche partitioning and individual specialization among age, breeding status and sex classes in a long-lived seabird. Anim Behav 2020. [DOI: 10.1016/j.anbehav.2020.10.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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19
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Carrasco TS, de Lima RC, Botta S, Machado R, Simões-Lopes PC, Ott PH, Secchi ER. Temporal and individual variation in the diet of the Neotropical otter, Lontra longicaudis (Olfers, 1818) (Carnivora, Mustelidae), as revealed by stable isotope analysis of vibrissae. Mamm Biol 2020. [DOI: 10.1007/s42991-020-00060-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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20
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Rodriguez CAB, de Lacerda LD, Bezerra MF, Moura VL, de Rezende CE, Bastos WR. Influence of size on total mercury (THg), methyl mercury (MeHg), and stable isotopes of N and C in green turtles (Chelonia mydas) from NE Brazil. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:20527-20537. [PMID: 32242319 DOI: 10.1007/s11356-020-08623-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 03/26/2020] [Indexed: 06/11/2023]
Abstract
The green turtle (Chelonia mydas) is known to present an herbivorous diet as an adult; however, juveniles may have an omnivore habit, and these changes in food preference may affect the uptake and accumulation of pollutants, such as mercury (Hg). In order to better understand the influence of this ontogenetic shift on Hg accumulation, this study evaluates the concentrations of total mercury (THg), methyl mercury (MeHg), and stable isotopes of carbon and nitrogen (δ13C and δ15N) in a group of juveniles of the green turtle. Tissue samples (liver, kidney, muscle, and scutes) were sampled from 47 turtles stranded dead on the coast of Bahia, NE, Brazil, between 2009 and 2013. The turtles analyzed showed a size range of 24.9-62.0 cm and an average of 36.4 ± 7.2 cm of curved carapace length. The scutes showed to be a viable method for Hg monitoring in the green turtles. The concentrations of THg and MeHg decreased with increasing size. The isotope values of δ15N and δ13C did not show a clear relationship with the size, suggesting that the green turtles used in our work would be occupying similar trophic levels, and foraging habitat.
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Affiliation(s)
- César Augusto Barrios Rodriguez
- Laboratório de Biogeoquímica Costeira, Instituto de Ciências do Mar, Universidade Federal do Ceará, Av. Abolição, 3207, Fortaleza, CE, 60165-081, Brazil.
| | - Luiz Drude de Lacerda
- Laboratório de Biogeoquímica Costeira, Instituto de Ciências do Mar, Universidade Federal do Ceará, Av. Abolição, 3207, Fortaleza, CE, 60165-081, Brazil
| | | | - Victor Lacerda Moura
- Laboratório de Biogeoquímica Costeira, Instituto de Ciências do Mar, Universidade Federal do Ceará, Av. Abolição, 3207, Fortaleza, CE, 60165-081, Brazil
| | - Carlos Eduardo de Rezende
- Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade estadual do Norte Fluminense, Darcy Ribeiro, Av. Alberto Lamego, 2000, Parque California, Campos dos Goytacazes, RJ, 28013-602, Brazil
| | - Wanderley Rodrigues Bastos
- Regional Development and Environment Postgraduate Program, Environmental Biogeochemistry Laboratory Wolfgang C. Pfeiffer, Rondônia Federal University, Av. Pres. Dutra, 2967, Olaria, Porto Velho, RO, 76801-059, Brazil
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21
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Jacquier M, Simon L, Ruette S, Vandel JM, Hemery A, Devillard S. Isotopic evidence of individual specialization toward free-ranging chickens in a rural population of red foxes. EUR J WILDLIFE RES 2020. [DOI: 10.1007/s10344-019-1352-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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22
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Musseau C, Vincenzi S, Santoul F, Boulêtreau S, Jesenšek D, Crivelli AJ. Within-individual trophic variability drives short-term intraspecific trait variation in natural populations. J Anim Ecol 2020; 89:921-932. [PMID: 31758696 DOI: 10.1111/1365-2656.13149] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 10/20/2019] [Indexed: 11/29/2022]
Abstract
Intraspecific trait variability (ITV) maintains functional diversity in populations and communities, and plays a crucial role in ecological and evolutionary processes such as trophic cascades or speciation. Furthermore, functional variation within a species and its populations can help buffer against harmful environmental changes. Trait variability within species can be observed from differences among populations, and between- and within individuals. In animals, ITV can be driven by ontogeny, the environment in which populations live and by within-individual specialization or variation unrelated to growth. However, we still know little about the relative strength of these drivers in determining ITV variation in natural populations. Here, we aimed to (a) measure the relative strength of between- and within-individual effects of body size on ITV over time, and (b) disentangle the trophic changes due to ontogeny from other sources of variability, such as the environment experienced by populations and individual preferences at varying temporal and spatial scales. We used as a model system the endangered marble trout Salmo marmoratus, a freshwater fish living in a restricted geographical area (<900 km2 ) that shows marked changes in diet through ontogeny. We investigated two trophic traits, trophic position and resource use, with stable isotopes (δ15 N and δ13 C), and followed over time 238 individually tagged marble trout from six populations to estimate the trophic changes between and within individuals through ontogeny at three different time-scales (short term: 3 months, medium term: 1 year and long term: 2 years). We found that the relative strength of between- and within-individual effects of body size on trophic position and resource use change strongly over time. Both effects played a similar role in ITV over medium- and long-term time-scales, but within-individual effects were significantly driving trophic variability over short-term scales. Apart from ontogenetic shifts, individuals showed variability in trophic traits as big as the variability estimated between populations. Overall, our results show how the relative strengths of ITV drivers change over time. This study evidences the crucial importance of considering effects of time-scales on functional variability at individual, population and species levels.
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Affiliation(s)
- Camille Musseau
- Department of Biology, Chemistry, Pharmacy, Institute of Biology, Freie Universität Berlin, Berlin, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research, Berlin, Germany.,Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Berlin, Germany.,EcoLab, Université de Toulouse, CNRS, Toulouse, France
| | - Simone Vincenzi
- Center for Stock Assessment Research, Department of Applied Mathematics and Statistics, University of California, Santa Cruz, CA, USA
| | | | | | | | - Alain J Crivelli
- Research Institute for the Conservation of Mediterranean Wetlands, Tour du Valat, Arles, France
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23
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Figgener C, Bernardo J, Plotkin PT. Beyond trophic morphology: stable isotopes reveal ubiquitous versatility in marine turtle trophic ecology. Biol Rev Camb Philos Soc 2019; 94:1947-1973. [PMID: 31338959 PMCID: PMC6899600 DOI: 10.1111/brv.12543] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 06/07/2019] [Accepted: 06/13/2019] [Indexed: 11/30/2022]
Abstract
The idea that interspecific variation in trophic morphology among closely related species effectively permits resource partitioning has driven research on ecological radiation since Darwin first described variation in beak morphology among Geospiza. Marine turtles comprise an ecological radiation in which interspecific differences in trophic morphology have similarly been implicated as a pathway to ecopartition the marine realm, in both extant and extinct species. Because marine turtles are charismatic flagship species of conservation concern, their trophic ecology has been studied intensively using stable isotope analyses to gain insights into habitat use and diet, principally to inform conservation management. This legion of studies provides an unparalleled opportunity to examine ecological partitioning across numerous hierarchical levels that heretofore has not been applied to any other ecological radiation. Our contribution aims to provide a quantitative analysis of interspecific variation and a comprehensive review of intraspecific variation in trophic ecology across different hierarchical levels marshalling insights about realised trophic ecology derived from stable isotopes. We reviewed 113 stable isotope studies, mostly involving single species, and conducted a meta-analysis of data from adults to elucidate differences in trophic ecology among species. Our study reveals a more intricate hierarchy of ecopartitioning by marine turtles than previously recognised based on trophic morphology and dietary analyses. We found strong statistical support for interspecific partitioning, as well as a continuum of intraspecific trophic sub-specialisation in most species across several hierarchical levels. This ubiquity of trophic specialisation across many hierarchical levels exposes a far more complex view of trophic ecology and resource-axis exploitation than suggested by species diversity alone. Not only do species segregate along many widely understood axes such as body size, macrohabitat, and trophic morphology but the general pattern revealed by isotopic studies is one of microhabitat segregation and variation in foraging behaviour within species, within populations, and among individuals. These findings are highly relevant to conservation management because they imply ecological non-exchangeability, which introduces a new dimension beyond that of genetic stocks which drives current conservation planning. Perhaps the most remarkable finding from our data synthesis is that four of six marine turtle species forage across several trophic levels. This pattern is unlike that seen in other large marine predators, which forage at a single trophic level according to stable isotopes. This finding affirms suggestions that marine turtles are robust sentinels of ocean health and likely stabilise marine food webs. This insight has broader significance for studies of marine food webs and trophic ecology of large marine predators. Beyond insights concerning marine turtle ecology and conservation, our findings also have broader implications for the study of ecological radiations. Particularly, the unrecognised complexity of ecopartitioning beyond that predicted by trophic morphology suggests that this dominant approach in adaptive radiation research likely underestimates the degree of resource overlap and that interspecific disparities in trophic morphology may often over-predict the degree of realised ecopartitioning. Hence, our findings suggest that stable isotopes can profitably be applied to study other ecological radiations and may reveal trophic variation beyond that reflected by trophic morphology.
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Affiliation(s)
- Christine Figgener
- Marine Biology Interdisciplinary ProgramTexas A&M University3258 TAMU, College StationTX77843U.S.A.
- Department of BiologyTexas A&M University3258 TAMU, College StationTX77843U.S.A.
- Department of OceanographyTexas A&M University3146 TAMU, College StationTX77843U.S.A.
| | - Joseph Bernardo
- Marine Biology Interdisciplinary ProgramTexas A&M University3258 TAMU, College StationTX77843U.S.A.
- Department of BiologyTexas A&M University3258 TAMU, College StationTX77843U.S.A.
- Program in Ecology and Evolutionary BiologyTexas A&M University2475 TAMU, College StationTX77843U.S.A.
| | - Pamela T. Plotkin
- Marine Biology Interdisciplinary ProgramTexas A&M University3258 TAMU, College StationTX77843U.S.A.
- Department of OceanographyTexas A&M University3146 TAMU, College StationTX77843U.S.A.
- Texas Sea Grant, Texas A&M University4115 TAMU, College StationTX77843U.S.A.
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24
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Year-round individual specialization in the feeding ecology of a long-lived seabird. Sci Rep 2019; 9:11812. [PMID: 31413291 PMCID: PMC6694139 DOI: 10.1038/s41598-019-48214-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 07/31/2019] [Indexed: 11/08/2022] Open
Abstract
Many generalist species are composed of individuals varying in the size of their realized niches within a population. To understand the underlying causes and implications of this phenomenon, repeated samplings on the same individuals subjected to different environmental conditions are needed. Here, we studied individual specialization of feeding strategies in breeding and non-breeding grounds of Cory's shearwaters (Calonectris borealis) for 2-8 years, and its relationship with fitness. Individuals were relatively flexible in non-breeding destinations, but specialized in diet, habitat use and daily activity across years. Daily activity was also consistent throughout the year for the same individual, suggesting that it is driven by individual constraints, whereas individual diet and habitat use changed between breeding and non-breeding grounds, indicating that these specializations may be learned at each area. Moreover, individuals that were intermediate specialized in their diet tended to show higher breeding success than those with weakly and highly specialized diets, suggesting stabilizing selection. Overall, this study suggests that the development of individual specialization is more flexible than previously thought, i.e. it emerges under specific environmental conditions and can develop differently when environmental conditions vary. However, once established, individual specialization may compromise the ability of individuals to cope with environmental stochasticity.
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25
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Villa CA, Bell I, Madden Hof C, Limpus CJ, Gaus C. Elucidating temporal trends in trace element exposure of green turtles (Chelonia mydas) using the toxicokinetic differences of blood and scute samples. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 651:2450-2459. [PMID: 30336435 DOI: 10.1016/j.scitotenv.2018.10.092] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 10/01/2018] [Accepted: 10/07/2018] [Indexed: 06/08/2023]
Abstract
Blood is considered a suitable biomonitoring matrix for evaluating relatively recent exposure to environmental contaminants since abrupt changes in exposure regimes are rapidly reflected in blood. On the other hand, keratinized tissues, such as turtle scutes, are known to integrate trace element exposure over relatively long time periods. This study aimed to test the use of the differences in blood and scute to inform on the historical trace element exposure of green turtles. We propose a blood-scute kinetic model to predict how an increase in exposure would affect the concentrations in these two matrices over time. We then tested the relationship between blood and scute concentrations for 19 trace elements in two green turtle populations presumed to experience relatively constant exposure conditions. Significant log-log and linear correlations were observed between blood and scute concentrations for Co, As, Mo, Sb, and Cd. We then analysed blood-scute ratios in turtles from two coastal sites with known elevated exposure to various trace elements from previous studies. Deviations from the steady-state were clearly evident in these coastal turtles (for Co and Cd) and were consistent with the model prediction of changes in exposure. These field data provide evidence that blood-scute ratios can provide a valuable tool for examining the historical trace element exposure of turtles. We further present a method by which the general model may be refined and validated, by using data from individual turtles that had been recaptured across multiple years. Although the timeframe and number of recaptured samples available for this study were limited, the temporal changes in blood-scute ratios in these animals were generally consistent with those suggested by the model. Thus, the ratio between paired blood and scute trace element concentrations could be used to establish a temporal exposure index in turtles.
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Affiliation(s)
- C A Villa
- Australian Rivers Institute, School of Environment and Science, Griffith University, Gold Coast, QLD 4222, Australia.
| | - I Bell
- Queensland Department of Environment and Science, Townsville, QLD 4810, Australia
| | - C Madden Hof
- World Wide Fund for Nature-Australia, Brisbane, QLD 4000, Australia
| | - C J Limpus
- Queensland Department of Environment and Science, Brisbane, QLD 4102, Australia
| | - C Gaus
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Woolloongabba, QLD 4102, Australia
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Pena SA, Mendes-Oliveira AC. Effect of oil palm (Elaeis guineensis Jacq.) plantations on individual-level diet variation of Hylaeamys megacephalus (G. Fisher 1814) (Rodentia, Cricetidae) in eastern Amazon Forest. BIOTA NEOTROPICA 2019. [DOI: 10.1590/1676-0611-bn-2018-0597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
Abstract
Abstract: In this study we described the diet of Hylaeamys megacephalus (G. Fisher, 1814) and investigated the degree of individual variation in the diet of this species among the Amazon Forest and the oil palm plantation. We analyzed the stomach contents of 36 individuals, of whom 11 were collected in the forest and 25 captured in the palm oil palm plantation. The H. megacephalus diet consisted of 18 food items, of which 12 were animal composition and eight were vegetable composition. The niche amplitude of the species was narrower in the forest area (Baforest = 0.013) compared to the palm tree plantation area (Bapalm = 0.478). This shows that individuals have greater niche overlap in forest areas, while in the plantation areas the animals expand their food niche. In addition, the values of the mean of the individual diet in relation to the diet of the entire population were lower in the palm oil palm plantation environment (ISpalm = 0.164) than in the Forest environment (ISforest = 0.357), indicating a high specialization in the palm oil plantation. These results indicate a population mechanism to reduce intraspecific competition in response to scarce resources.
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Wildermann NE, Gredzens C, Avens L, Barrios-Garrido HA, Bell I, Blumenthal J, Bolten AB, Braun McNeill J, Casale P, Di Domenico M, Domit C, Epperly SP, Godfrey MH, Godley BJ, González-Carman V, Hamann M, Hart KM, Ishihara T, Mansfield KL, Metz TL, Miller JD, Pilcher NJ, Read MA, Sasso C, Seminoff JA, Seney EE, Willard AS, Tomás J, Vélez-Rubio GM, Ware M, Williams JL, Wyneken J, Fuentes MMPB. Informing research priorities for immature sea turtles through expert elicitation. ENDANGER SPECIES RES 2018. [DOI: 10.3354/esr00916] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Votier SC, Fayet AL, Bearhop S, Bodey TW, Clark BL, Grecian J, Guilford T, Hamer KC, Jeglinski JWE, Morgan G, Wakefield E, Patrick SC. Effects of age and reproductive status on individual foraging site fidelity in a long-lived marine predator. Proc Biol Sci 2018; 284:rspb.2017.1068. [PMID: 28747480 PMCID: PMC5543227 DOI: 10.1098/rspb.2017.1068] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 06/19/2017] [Indexed: 12/22/2022] Open
Abstract
Individual foraging specializations, where individuals use a small component of the population niche width, are widespread in nature with important ecological and evolutionary implications. In long-lived animals, foraging ability develops with age, but we know little about the ontogeny of individuality in foraging. Here we use precision global positioning system (GPS) loggers to examine how individual foraging site fidelity (IFSF), a common component of foraging specialization, varies between breeders, failed breeders and immatures in a long-lived marine predator-the northern gannet Morus bassanus Breeders (aged 5+) showed strong IFSF: they had similar routes and were faithful to distal points during successive trips. However, centrally placed immatures (aged 2-3) were far more exploratory and lacked route or foraging site fidelity. Failed breeders were intermediate: some with strong fidelity, others being more exploratory. Individual foraging specializations were previously thought to arise as a function of heritable phenotypic differences or via social transmission. Our results instead suggest a third alternative-in long-lived species foraging sites are learned during exploratory behaviours early in life, which become canalized with age and experience, and refined where possible-the exploration-refinement foraging hypothesis. We speculate similar patterns may be present in other long-lived species and moreover that long periods of immaturity may be a consequence of such memory-based individual foraging strategies.
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Affiliation(s)
- Stephen C Votier
- Environment and Sustainability Institute, University of Exeter, Penryn Campus, Cornwall TR10 9EZ, UK .,Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Cornwall TR10 9EZ, UK
| | - Annette L Fayet
- Animal Behaviour Research Group, Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
| | - Stuart Bearhop
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Cornwall TR10 9EZ, UK
| | - Thomas W Bodey
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Cornwall TR10 9EZ, UK
| | - Bethany L Clark
- Environment and Sustainability Institute, University of Exeter, Penryn Campus, Cornwall TR10 9EZ, UK.,Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Cornwall TR10 9EZ, UK
| | - James Grecian
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
| | - Tim Guilford
- Animal Behaviour Research Group, Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
| | - Keith C Hamer
- School of Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Jana W E Jeglinski
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
| | - Greg Morgan
- RSPB Ramsey Island, St David's, Pembrokeshire SA62 6PY, UK
| | - Ewan Wakefield
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
| | - Samantha C Patrick
- School of Environmental Sciences, University of Liverpool, Nicholson Building, Brownlow Street, Liverpool L69 3GP, UK
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Price JT, Paladino FV, Lamont MM, Witherington BE, Bates ST, Soule T. Characterization of the juvenile green turtle (Chelonia mydas) microbiome throughout an ontogenetic shift from pelagic to neritic habitats. PLoS One 2017; 12:e0177642. [PMID: 28493980 PMCID: PMC5426784 DOI: 10.1371/journal.pone.0177642] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 05/01/2017] [Indexed: 02/01/2023] Open
Abstract
The gut microbiome of herbivorous animals consists of organisms that efficiently digest the structural carbohydrates of ingested plant material. Green turtles (Chelonia mydas) provide an interesting model of change in these microbial communities because they undergo a pronounced shift from a surface-pelagic distribution and omnivorous diet to a neritic distribution and herbivorous diet. As an alternative to direct sampling of the gut, we investigated the cloacal microbiomes of juvenile green turtles before and after recruitment to neritic waters to observe any changes in their microbial community structure. Cloacal swabs were taken from individual turtles for analysis of the 16S rRNA gene sequences using Illumina sequencing. One fecal sample was also obtained, allowing for a preliminary comparison with the bacterial community of the cloaca. We found significant variation in the juvenile green turtle bacterial communities between pelagic and neritic habitats, suggesting that environmental and dietary factors support different bacterial communities in green turtles from these habitats. This is the first study to characterize the cloacal microbiome of green turtles in the context of their ontogenetic shifts, which could provide valuable insight into the origins of their gut bacteria and how the microbial community supports their shift to herbivory.
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Affiliation(s)
- James T. Price
- Department of Biology, Indiana University-Purdue University, Fort Wayne, Indiana, United States of America
| | - Frank V. Paladino
- Department of Biology, Indiana University-Purdue University, Fort Wayne, Indiana, United States of America
| | | | - Blair E. Witherington
- Disney’s Animals, Science, and Environment, Lake Buena Vista, Florida, United States of America
| | - Scott T. Bates
- Department of Biological Sciences, Purdue University Northwest, Westville, Indiana, United States of America
| | - Tanya Soule
- Department of Biology, Indiana University-Purdue University, Fort Wayne, Indiana, United States of America
- * E-mail:
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30
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Powell EC, Taylor LA. Specialists and generalists coexist within a population of spider-hunting mud dauber wasps. Behav Ecol 2017; 28:890-898. [PMID: 29622922 PMCID: PMC5873241 DOI: 10.1093/beheco/arx050] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 03/06/2017] [Accepted: 03/14/2017] [Indexed: 01/05/2023] Open
Abstract
Individual foraging specialization describes the phenomenon where conspecifics within a population of generalists exhibit differences in foraging behavior, each specializing on different prey types. Individual specialization is widespread in animals, yet is understudied in invertebrates, despite potential impacts to food web and population dynamics. Sceliphron caementarium (Hymenoptera: Sphecidae) is an excellent system to examine individual specialization. Females of these mud dauber wasps capture and paralyze spiders which they store in mud nests to provision their offspring. Individuals may make hundreds of prey choices in their short lifespan and fully intact prey items can be easily excavated from their mud nests, where each distinct nest cell represents a discrete foraging bout. Using data collected from a single population of S. caementarium (where all individuals had access to the same resources), we found evidence of strong individual specialization; individuals utilized different resources (with respect to prey taxa, prey ecological guild, and prey size) to provision their nests. The extent of individual specialization differed widely within the population with some females displaying extreme specialization (taking only prey from a single species) while others were generalists (taking prey from up to 6 spider families). We also found evidence of temporal consistency in individual specialization over multiple foraging events. We discuss these findings broadly in the context of search images, responses to changing prey availability, and intraspecific competition pressure.
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Affiliation(s)
- Erin C Powell
- Entomology and Nematology Department, University of Florida, 1881 Natural Area Drive, Gainesville, FL 32611, USA.,School of Biological Sciences, University of Auckland, 3A Symonds St, Auckland Central 1010, New Zealand, and
| | - Lisa A Taylor
- Entomology and Nematology Department, University of Florida, 1881 Natural Area Drive, Gainesville, FL 32611, USA.,Florida Museum of Natural History, University of Florida, 3215 Hull Road, Gainesville, FL 32611, USA
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Rees AF, Alfaro-Shigueto J, Barata PCR, Bjorndal KA, Bolten AB, Bourjea J, Broderick AC, Campbell LM, Cardona L, Carreras C, Casale P, Ceriani SA, Dutton PH, Eguchi T, Formia A, Fuentes MMPB, Fuller WJ, Girondot M, Godfrey MH, Hamann M, Hart KM, Hays GC, Hochscheid S, Kaska Y, Jensen MP, Mangel JC, Mortimer JA, Naro-Maciel E, Ng CKY, Nichols WJ, Phillott AD, Reina RD, Revuelta O, Schofield G, Seminoff JA, Shanker K, Tomás J, van de Merwe JP, Van Houtan KS, Vander Zanden HB, Wallace BP, Wedemeyer-Strombel KR, Work TM, Godley BJ. Are we working towards global research priorities for management and conservation of sea turtles? ENDANGER SPECIES RES 2016. [DOI: 10.3354/esr00801] [Citation(s) in RCA: 175] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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32
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Bakker ES, Wood KA, Pagès JF, Veen G(C, Christianen MJ, Santamaría L, Nolet BA, Hilt S. Herbivory on freshwater and marine macrophytes: A review and perspective. AQUATIC BOTANY 2016. [PMID: 0 DOI: 10.1016/j.aquabot.2016.04.008] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
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Vander Zanden HB, Bolten AB, Tucker AD, Hart KM, Lamont MM, Fujisaki I, Reich KJ, Addison DS, Mansfield KL, Phillips KF, Pajuelo M, Bjorndal KA. Biomarkers reveal sea turtles remained in oiled areas following the Deepwater Horizon oil spill. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2016; 26:2145-2155. [PMID: 27755731 DOI: 10.1002/eap.1366] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 01/19/2016] [Accepted: 03/08/2016] [Indexed: 06/06/2023]
Abstract
Assessments of large-scale disasters, such as the Deepwater Horizon oil spill, are problematic because while measurements of post-disturbance conditions are common, measurements of pre-disturbance baselines are only rarely available. Without adequate observations of pre-disaster organismal and environmental conditions, it is impossible to assess the impact of such catastrophes on animal populations and ecological communities. Here, we use long-term biological tissue records to provide pre-disaster data for a vulnerable marine organism. Keratin samples from the carapace of loggerhead sea turtles record the foraging history for up to 18 years, allowing us to evaluate the effect of the oil spill on sea turtle foraging patterns. Samples were collected from 76 satellite-tracked adult loggerheads in 2011 and 2012, approximately one to two years after the spill. Of the 10 individuals that foraged in areas exposed to surface oil, none demonstrated significant changes in foraging patterns post spill. The observed long-term fidelity to foraging sites indicates that loggerheads in the northern Gulf of Mexico likely remained in established foraging sites, regardless of the introduction of oil and chemical dispersants. More research is needed to address potential long-term health consequences to turtles in this region. Mobile marine organisms present challenges for researchers to monitor effects of environmental disasters, both spatially and temporally. We demonstrate that biological tissues can reveal long-term histories of animal behavior and provide critical pre-disaster baselines following an anthropogenic disturbance or natural disaster.
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Affiliation(s)
- Hannah B Vander Zanden
- Department of Geology and Geophysics, University of Utah, 115 S 1460 E Salt Lake City, Utah, 84112, USA.
- Archie Carr Center for Sea Turtle Research and Department of Biology, University of Florida, PO Box 118525 Gainesville, Florida, 32611, USA.
| | - Alan B Bolten
- Archie Carr Center for Sea Turtle Research and Department of Biology, University of Florida, PO Box 118525 Gainesville, Florida, 32611, USA
| | - Anton D Tucker
- Mote Marine Laboratory, 1600 Ken Thompson Pkwy, Sarasota, Florida, 34236, USA
| | - Kristen M Hart
- Wetland and Aquatic Research Center, U.S. Geological Survey, 3321 College Ave, Davie, Florida, 33314, USA
| | - Margaret M Lamont
- Wetland and Aquatic Research Center, U.S. Geological Survey, 7920 NW 71St St, Gainesville, Florida, 32653, USA
| | - Ikuko Fujisaki
- Ft. Lauderdale Research and Education Center, University of Florida, 3205 College Ave, Davie, Florida, 33314, USA
| | - Kimberly J Reich
- Texas A & M Galveston, P.O. Box 1675, Galveston, Texas, 77553, USA
| | - David S Addison
- Conservancy of Southwest Florida, 1495 Smith Preserve Way, Naples, Florida, 34102, USA
| | - Katherine L Mansfield
- Department of Biology, University of Central Florida, 4110 Libra Dr, Orlando, Florida, 32816, USA
| | - Katrina F Phillips
- Department of Biology, University of Central Florida, 4110 Libra Dr, Orlando, Florida, 32816, USA
| | - Mariela Pajuelo
- Archie Carr Center for Sea Turtle Research and Department of Biology, University of Florida, PO Box 118525 Gainesville, Florida, 32611, USA
| | - Karen A Bjorndal
- Archie Carr Center for Sea Turtle Research and Department of Biology, University of Florida, PO Box 118525 Gainesville, Florida, 32611, USA
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Codron D, Codron J, Sponheimer M, Clauss M. Within-Population Isotopic Niche Variability in Savanna Mammals: Disparity between Carnivores and Herbivores. Front Ecol Evol 2016. [DOI: 10.3389/fevo.2016.00015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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35
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Wakefield ED, Cleasby IR, Bearhop S, Bodey TW, Davies RD, Miller PI, Newton J, Votier SC, Hamer KC. Long-term individual foraging site fidelity—why some gannets don't change their spots. Ecology 2015; 96:3058-74. [DOI: 10.1890/14-1300.1] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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36
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Rossman S, Ostrom PH, Stolen M, Barros NB, Gandhi H, Stricker CA, Wells RS. Individual specialization in the foraging habits of female bottlenose dolphins living in a trophically diverse and habitat rich estuary. Oecologia 2015; 178:415-25. [PMID: 25656585 DOI: 10.1007/s00442-015-3241-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 01/14/2015] [Indexed: 10/24/2022]
Abstract
We examine individual specialization in foraging habits (foraging habitat and trophic level) of female bottlenose dolphins (Tursiops truncatus) resident in Sarasota Bay, Florida, USA, by analyzing time series of stable isotope (δ(15)N and δ(13)C) values in sequential growth layer groups within teeth. The isotope data provide a chronology of foraging habits over the lifetime of the individual and allowed us to show that female bottlenose dolphins exhibit a high degree of individual specialization in both foraging habitat and trophic level. The foraging habits used by adult females are similar to those they used as calves and may be passed down from mother to calf through social learning. We also characterized the foraging habits and home range of each individual by constructing standard ellipses from isotope values and dolphin sightings data (latitude and longitude), respectively. These data show that Sarasota Bay bottlenose dolphins forage within a subset of the habitats in which they are observed. Moreover, females with similar observational standard ellipses often possessed different foraging specializations. Female bottlenose dolphins may demonstrate individual specialization in foraging habits because it reduces some of the cost of living in groups, such as competition for prey.
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Affiliation(s)
- Sam Rossman
- Department of Integrative Biology, Michigan State University, East Lansing, MI, 48824, USA,
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Shimada T, Aoki S, Kameda K, Hazel J, Reich K, Kamezaki N. Site fidelity, ontogenetic shift and diet composition of green turtles Chelonia mydas in Japan inferred from stable isotope analysis. ENDANGER SPECIES RES 2014. [DOI: 10.3354/esr00616] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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38
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López-Castro MC, Bjorndal KA, Bolten AB. Evaluation of scute thickness to infer life history records in the carapace of green and loggerhead turtles. ENDANGER SPECIES RES 2014. [DOI: 10.3354/esr00593] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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