1
|
Stockin KA, Machovsky-Capuska GE, Palmer EI, Amiot C. Multidimensional trace metals and nutritional niche differ between sexually immature and mature common dolphins (Delphinus delphis). Environ Pollut 2023; 333:121935. [PMID: 37263561 DOI: 10.1016/j.envpol.2023.121935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 05/28/2023] [Accepted: 05/29/2023] [Indexed: 06/03/2023]
Abstract
There is a need to understand the links between metals and nutrition for apex marine predators, which may be subject to different ecotoxicological effects at different life stages. We combined stomach content analyses (SCA), prey composition analysis (PCA), the Multidimensional Niche Framework (MNNF) with Bayesian multivariate ellipses, trace metal analysis and nicheROVER to investigate nutrition and trace metals across sex, age, and sexual maturity status in common dolphins (Delphinus delphis) from New Zealand. A broader prey composition niche breadth (SEAc) was estimated for immature compared to mature conspecifics, showing a higher degree of prey and nutrient generalism driven by protein (P) intake. Cd and Zn niche similarities suggests these metals were incorporated through similar prey in both immature and mature dolphins, whereas Hg and Se niche divergence indicates uptake occurred via different prey. Our multidisciplinary assessment demonstrated how nutrients and metal interactions differ in common dolphins depending upon sexual maturity. This approach has relevance when considering how marine pollution, environmental fluctuations and climate change may affect nutritional and trace metal interactions during different reproductive stages within marine predators.
Collapse
Affiliation(s)
- Karen A Stockin
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, Auckland, 0745, New Zealand; Animal Welfare Science and Bioethics Centre, School of Veterinary Science, Massey University, Private Bag 11-222, Palmerston North, 4442, New Zealand.
| | - Gabriel E Machovsky-Capuska
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, Auckland, 0745, New Zealand; Nutri Lens, East Ryde, NSW, 2113, Australia
| | - Emily I Palmer
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, Auckland, 0745, New Zealand
| | - Christophe Amiot
- UFR Science et Technologie, Nantes Université, 44000, Nantes, France; BiodivAG, Angers Université, Angers, 49000, France
| |
Collapse
|
2
|
Loayza E, Muñoz-Saravia A, De Troch M, Hendriks WH, Janssens GPJ. Detailed whole-body nutrient analysis identifies differences in feeding ecology between related fish species: The case of Orestias native Andean killifish in Lake Titicaca. J Anim Physiol Anim Nutr (Berl) 2023; 107:1302-1310. [PMID: 37203287 DOI: 10.1111/jpn.13831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 05/02/2023] [Accepted: 05/03/2023] [Indexed: 05/20/2023]
Abstract
Body nutrient profiles in ecological studies allow for relating the nutritional status of consumers and their effects on the movement and retention of elements in ecosystems, as well as reflecting feeding conditions and habitat quality. This study compared the detailed whole-body nutrient composition (macronutrients, minerals, fatty acids and amino acids) of two omnivorous natives Orestias killifish from Lake Titicaca (Orestias agassizii and Orestias luteus, Valenciennes), the largest lake in the Andes, as an indirect tool to understand differences in their feeding ecology. Although both species are usually described as omnivorous fish, both have amphipods (Hyalella spp) as their main food source. Our results showed that both killifish had a comparable macronutrient composition, and the mineral concentrations of Mg, P and Ca (reflecting bony structures) differed between them. Many of the saturated fatty acids were significantly lower in O. luteus, and O. agassizii had higher concentrations of cis-vaccenic acid (18:1n11 (cis)), supporting the idea of a higher algal contribution to the diet of this fish. The lower histidine and higher taurine concentrations in O. agassizii compared with O. luteus (independent of body size) may reflect its ubiquitous behaviour and plasticity. This study shows how whole-body nutrient analysis can identify differences in feeding ecology and feeding behaviour between related species.
Collapse
Affiliation(s)
- Erick Loayza
- Department of Veterinary and Biosciences, Ghent University, Merelbeke, Belgium
- Unidad de Ecología Acuática, Instituto de Ecología, Carrera de Biología-Facultad de Ciencias Puras y Naturales, Universidad Mayor de San Andrés, La Paz, Bolivia
| | | | - Marleen De Troch
- Biology Department, Marine Biology, Ghent University, Ghent, Belgium
| | - Wouter H Hendriks
- Animal Nutrition Group, Wageningen University, Wageningen, The Netherlands
| | - Geert P J Janssens
- Department of Veterinary and Biosciences, Ghent University, Merelbeke, Belgium
| |
Collapse
|
3
|
Valenzuela-Toro AM, Mehta R, Pyenson ND, Costa DP, Koch PL. Feeding morphology and body size shape resource partitioning in an eared seal community. Biol Lett 2023; 19:20220534. [PMID: 36883314 PMCID: PMC9993223 DOI: 10.1098/rsbl.2022.0534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023] Open
Abstract
Body size and feeding morphology influence how animals partition themselves within communities. We tested the relationships among sex, body size, skull morphology and foraging in sympatric otariids (eared seals) from the eastern North Pacific Ocean, the most diverse otariid community in the world. We recorded skull measurements and stable carbon (δ13C) and nitrogen (δ15N) isotope values (proxies for foraging) from museum specimens in four sympatric species: California sea lions (Zalophus californianus), Steller sea lions (Eumetopias jubatus), northern fur seals (Callorhinus ursinus) and Guadalupe fur seals (Arctocephalus townsendi). Species and sexes had statistical differences in size, skull morphology and foraging significantly affecting the δ13C values. Sea lions had higher δ13C values than fur seals, and males of all species had higher values than females. The δ15N values were correlated with species and feeding morphology; individuals with stronger bite forces had higher δ15N values. We also found a significant community-wide correlation between skull length (indicator of body length), and foraging, with larger individuals having nearshore habitat preferences, and consuming higher trophic level prey than smaller individuals. Still, there was no consistent association between these traits at the intraspecific level, indicating that other factors might account for foraging variability.
Collapse
Affiliation(s)
- Ana M Valenzuela-Toro
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA 95060, USA.,Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20560, USA
| | - Rita Mehta
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA 95060, USA
| | - Nicholas D Pyenson
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA 95060, USA.,Department of Paleontology and Geology, Burke Museum of Natural History and Culture, Seattle, WA 98105, USA
| | - Daniel P Costa
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA 95060, USA.,Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | - Paul L Koch
- Department of Earth and Planetary Sciences, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| |
Collapse
|
4
|
Dwyer GK, Stoffels RJ, Silvester E, Rees GN. Two wild carnivores selectively forage for prey but not amino acids. Sci Rep 2023; 13:3254. [PMID: 36828827 PMCID: PMC9958011 DOI: 10.1038/s41598-023-28231-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 01/16/2023] [Indexed: 02/26/2023] Open
Abstract
In nutritional ecology the intake target is the diet that maximises consumer fitness. A key hypothesis of nutritional ecology is that natural selection has acted upon the behavioural and physiological traits of consumers to result in them Selectively Consuming prey to match the Intake Target (SCIT). SCIT has been documented in some herbivores and omnivores, which experience strong heterogeneity in the nutritional quality of available foods. Although carnivores experience a prey community with a much more homogeneous nutrient composition, SCIT by carnivores has nevertheless been deemed highly likely by some researchers. Here we test for SCIT for micronutrients (amino acids) in two freshwater carnivores: the river blackfish and the two-spined blackfish. Although both blackfishes exhibited non-random consumption of prey from the environment, this resulted in non-random consumption of amino acids in only one species, the river blackfish. Non-random consumption of amino acids by river blackfish was not SCIT, but instead an artefact of habitat-specific foraging. We present hypotheses to explain why wild populations of freshwater carnivores may not exhibit SCIT for amino acids. Our work highlights the need for careful, critical tests of the hypotheses and assumptions of nutritional ecology and its application to wild populations.
Collapse
Affiliation(s)
- Georgia K Dwyer
- Centre for Regional and Rural Futures, Deakin University, Locked Bag 20000, Geelong, VIC, 3220, Australia.
| | - Rick J Stoffels
- National Institute of Water and Atmospheric Research, Riccarton, PO Box 8602, Christchurch, 8440, New Zealand
| | - Ewen Silvester
- Department of Ecology, Environment and Evolution, Centre for Freshwater Ecosystems, School of Life Sciences, La Trobe University, Wodonga, VIC, 3690, Australia
| | - Gavin N Rees
- CSIRO Land and Water, and Institute for Land, Water and Society, Charles Sturt University, PO Box 789, Albury, NSW, 2640, Australia
| |
Collapse
|
5
|
Hansen MJ, Krause S, Dhellemmes F, Pacher K, Kurvers RHJM, Domenici P, Krause J. Mechanisms of prey division in striped marlin, a marine group hunting predator. Commun Biol 2022; 5:1161. [PMID: 36316537 PMCID: PMC9622829 DOI: 10.1038/s42003-022-03951-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 09/06/2022] [Indexed: 11/18/2022] Open
Abstract
Many terrestrial group-hunters cooperate to kill prey but then compete for their share with dominance being a strong predictor of prey division. In contrast, little is known about prey division in group-hunting marine predators that predominately attack small, evasive prey (e.g. fish schools). We identified individual striped marlin (Kajikia audax) hunting in groups. Groups surrounded prey but individuals took turns attacking. We found that competition for prey access led to an unequal division of prey among the predators, with 50% of the most frequently attacking marlin capturing 70–80% of the fish. Neither aggression, body size nor variation in hunting efficiency explained this skewed prey division. We did find that newly arrived groups of marlin gained on average more access to the prey. This raises the possibility that newly arrived marlin were hungrier and more motivated to feed. However, this result does not necessarily explain the unequal prey division among the predators because the skew in prey captures was found at the level of these groups. Dynamic prey division is probably widespread but under-reported in marine group-hunters and the inability of individuals to monopolize prey until satiation likely reduces the importance of social hierarchies for prey division. Striped marlin use a dynamic prey division method when hunting as a group, taking turns to feed but without doing so equally.
Collapse
Affiliation(s)
- M. J. Hansen
- grid.419247.d0000 0001 2108 8097Department of Fish Biology, Fisheries and Aquaculture, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany
| | - S. Krause
- grid.4562.50000 0001 0057 2672Department of Electrical Engineering and Computer Science, Lübeck University of Applied Sciences, 23562 Lübeck, Germany
| | - F. Dhellemmes
- grid.419247.d0000 0001 2108 8097Department of Fish Biology, Fisheries and Aquaculture, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany
| | - K. Pacher
- grid.7468.d0000 0001 2248 7639Faculty of Life Science, Humboldt-Universität zu Berlin, Invalidenstrasse 42, 10115 Berlin, Germany
| | - R. H. J. M. Kurvers
- grid.419247.d0000 0001 2108 8097Department of Fish Biology, Fisheries and Aquaculture, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany ,grid.419526.d0000 0000 9859 7917Center for Adaptive Rationality, Max Planck Institute for Human Development, Lentzeallee 94, 14195 Berlin, Germany
| | - P. Domenici
- grid.5326.20000 0001 1940 4177IBF-CNR, Consiglio Nazionale delle Ricerche, Area di Ricerca San Cataldo, Via G. Moruzzi N°1, 56124 Pisa, Italy ,IAS-CNR, Località Sa Mardini, 09170 Torregrande, Oristano Italy
| | - J. Krause
- grid.419247.d0000 0001 2108 8097Department of Fish Biology, Fisheries and Aquaculture, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany ,grid.6734.60000 0001 2292 8254Cluster of Excellence “Science of Intelligence,” Technical University of Berlin, Marchstr. 23, 10587 Berlin, Germany ,grid.7468.d0000 0001 2248 7639Present Address: Faculty of Life Science, Humboldt-Universität zu Berlin, Invalidenstrasse 42, 10115 Berlin, Germany
| |
Collapse
|
6
|
Abstract
Climate change directly impacts the foraging opportunities of cetaceans (e.g. lower prey availability), leads to habitat loss, and forces cetaceans to move to other feeding grounds. The rise in ocean temperature, low prey availability and loss of habitat can have severe consequences for cetacean survival, particularly those species that are already threatened or those with a limited habitat range. In addition, it is predicted that the concentration of contaminants in aquatic environments will increase owing to Arctic meltwater and increased rainfall events leading to higher rates of land-based runoff in downstream coastal areas. These persistent and mobile contaminants can bioaccumulate in the ecosystem, and lead to ecotoxicity with potentially severe consequences on the reproductive organs, immune system and metabolism of marine mammals. There is a need to measure and assess the cumulative impact of multiple stressors, given that climate change, habitat alteration, low prey availability and contaminants do not act in isolation. Human-caused perturbations to cetacean foraging abilities are becoming a pervasive and prevalent threat to many cetacean species on top of climate change-associated stressors. We need to move to a greater understanding of how multiple stressors impact the metabolism of cetaceans and ultimately their population trajectory. This article is part of the theme issue 'Nurturing resilient marine ecosystems'.
Collapse
Affiliation(s)
- Anna Kebke
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
| | - Filipa Samarra
- University of Iceland's Institute of Research Centres, Vestmannaeyjar, Iceland
| | - Davina Derous
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
| |
Collapse
|
7
|
Stricker CA, Rode KD, Taras BD, Bromaghin JF, Horstmann L, Quakenbush L. Summer/fall diet and macronutrient assimilation in an Arctic predator. Oecologia 2022. [PMID: 35412091 DOI: 10.1007/s00442-022-05155-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 03/28/2022] [Indexed: 10/18/2022]
Abstract
Free-ranging predator diet estimation is commonly achieved by applying molecular-based tracers because direct observation is not logistically feasible or robust. However, tracers typically do not represent all dietary macronutrients, which likely obscures resource use as prey proximate composition varies and tissue consumption can be specific. For example, polar bears (Ursus maritimus) preferentially consume blubber, yet diets have been estimated using fatty acids based on prey blubber or stable isotopes of lipid-extracted prey muscle, neither of which represent both protein and lipid macronutrient contributions. Further, additional bias can be introduced because dietary fat is known to be flexibly routed beyond short-term energy production and storage. We address this problem by simultaneously accounting for protein and lipid assimilation using carbon and nitrogen isotope compositions of lipid-containing prey muscle and blubber to infer summer/fall diet composition and macronutrient proportions from Chukchi Sea polar bear guard hair (n = 229) sampled each spring between 2008 and 2017. Inclusion of blubber (85-95% lipid by dry mass) expanded the isotope mixing space and improved separation among prey species. Ice-associated seals, including nutritionally dependent pups, were the primary prey in summer/fall diets with lower contributions by Pacific walruses (Odobenus rosmarus) and whales. Percent blubber estimates confirmed preferential selection of this tissue and represented the highest documented lipid assimilation for any animal species. Our results offer an improved understanding of summer/fall prey macronutrient usage by Chukchi Sea polar bears which likely coincides with a nutritional bottleneck as the sea ice minimum is approached.
Collapse
|
8
|
Anderson AB, Fiuza TMJ, Araujo GS, Canterle AM, Canto LMC, Freitas RHA, Gadig OBF, Floeter SR. A safe haven for potential reproductive aggregations of the critically endangered Brazilian guitarfish (Pseudobatos horkelii). J Fish Biol 2021; 99:2030-2034. [PMID: 34402530 DOI: 10.1111/jfb.14880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 07/30/2021] [Accepted: 08/13/2021] [Indexed: 06/13/2023]
Abstract
Brazilian endemic batoid elasmobranch populations have declined dramatically in the past 40 years due to anthropic activities (e.g., overfishing). The Brazilian guitarfish, Pseudobatos horkelii, included in the IUCN red list of endangered species [Critically Endangered (CR)], has been captured as by-catch by trawling fishing boats to the edge of extinction. Despite governmental conservation initiatives, the species is still caught and commercialized along the Brazilian coast. In this study, the authors report three rare aggregation events for the Brazilian coast of P. horkelii, inside the only nearshore no-entry Brazilian marine protected area. Strategies for its protection are also discussed.
Collapse
Affiliation(s)
- Antônio B Anderson
- Laboratory of Ichthyology, Department of Oceanography, Federal University of Espírito Santo, Vitória, Brazil
| | - Thiago M J Fiuza
- Marine Macroecology and Biogeography Laboratory, Department of Ecology and Zoology, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Gabriel S Araujo
- Marine Macroecology and Biogeography Laboratory, Department of Ecology and Zoology, Federal University of Santa Catarina, Florianópolis, Brazil
- Universidade Federal do Rio de Janeiro, Instituto de Biodiversidade e Sustentabilidade, NUPEM/UFRJ, Avenida São José Barreto, Macaé, Brazil
| | - Angela M Canterle
- Marine Macroecology and Biogeography Laboratory, Department of Ecology and Zoology, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Luiza M C Canto
- Biology of Teleosts and Elasmobranchs Laboratory (LABITEL), Department of Ecology and Zoology, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Renato H A Freitas
- Biology of Teleosts and Elasmobranchs Laboratory (LABITEL), Department of Ecology and Zoology, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Otto B F Gadig
- Elasmobranch Research Laboratory, São Paulo State University, Campus do Litoral Paulista, Pça. Infante Dom Henrique, São Vicente, Brazil
| | - Sergio R Floeter
- Marine Macroecology and Biogeography Laboratory, Department of Ecology and Zoology, Federal University of Santa Catarina, Florianópolis, Brazil
| |
Collapse
|
9
|
Stockin KA, Pantos O, Betty EL, Pawley MDM, Doake F, Masterton H, Palmer EI, Perrott MR, Nelms SE, Machovsky-Capuska GE. Fourier transform infrared (FTIR) analysis identifies microplastics in stranded common dolphins (Delphinus delphis) from New Zealand waters. Mar Pollut Bull 2021; 173:113084. [PMID: 34775153 DOI: 10.1016/j.marpolbul.2021.113084] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 10/17/2021] [Accepted: 10/17/2021] [Indexed: 06/13/2023]
Abstract
Here we provide a first assessment of microplastics (MPs) in stomach contents of 15 common dolphins (Delphinus delphis) from both single and mass stranding events along the New Zealand coast between 2019 and 2020. MPs were observed in all examined individuals, with an average of 7.8 pieces per stomach. Most MPs were fragments (77%, n = 90) as opposed to fibres (23%, n = 27), with translucent/clear (46%) the most prevalent colour. Fourier transform infrared (FTIR) spectroscopy revealed polyethylene terephthalate (65%) as the most predominant polymer in fibres, whereas polypropylene (31%) and acrylonitrile butadiene styrene (20%) were more frequently recorded as fragments. Mean fragment and fibre size was 584 μm and 1567 μm, respectively. No correlation between total number of MPs and biological parameters (total body length, age, sexual maturity, axillary girth, or blubber thickness) was observed, with similar levels of MPs observed between each of the mass stranding events. Considering MPs are being increasingly linked to a wide range of deleterious effects across taxa, these findings in a typically pelagic marine sentinel species warrants further investigation.
Collapse
Affiliation(s)
- Karen A Stockin
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, Private Bag 102 904, Auckland 0745, New Zealand.
| | - Olga Pantos
- Institute of Environmental Science and Research, 27 Creyke Rd, Ilam, Christchurch 8041, New Zealand
| | - Emma L Betty
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, Private Bag 102 904, Auckland 0745, New Zealand
| | - Matthew D M Pawley
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, Private Bag 102 904, Auckland 0745, New Zealand
| | - Fraser Doake
- Institute of Environmental Science and Research, 27 Creyke Rd, Ilam, Christchurch 8041, New Zealand
| | - Hayden Masterton
- Institute of Environmental Science and Research, 27 Creyke Rd, Ilam, Christchurch 8041, New Zealand
| | - Emily I Palmer
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, Private Bag 102 904, Auckland 0745, New Zealand
| | - Matthew R Perrott
- School of Veterinary Science, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand
| | - Sarah E Nelms
- Centre for Ecology and Conservation, University of Exeter, Cornwall TR10 9EZ, United Kingdom
| | - Gabriel E Machovsky-Capuska
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, Private Bag 102 904, Auckland 0745, New Zealand
| |
Collapse
|
10
|
Stockin KA, Yi S, Northcott GL, Betty EL, Machovsky-Capuska GE, Jones B, Perrott MR, Law RJ, Rumsby A, Thelen MA, Graham L, Palmer EI, Tremblay LA. Per- and polyfluoroalkyl substances (PFAS), trace elements and life history parameters of mass-stranded common dolphins (Delphinus delphis) in New Zealand. Mar Pollut Bull 2021; 173:112896. [PMID: 34601248 DOI: 10.1016/j.marpolbul.2021.112896] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 08/19/2021] [Accepted: 08/20/2021] [Indexed: 06/13/2023]
Abstract
Profiles of 33 PFAS analytes and 12 essential and non-essential trace elements were measured in livers of stranded common dolphins (Delphinus delphis) from New Zealand. PFAS concentrations reported were largely comparable to those measured in other marine mammal species globally and composed mostly of long-chain compounds including perfluorooctanesulfonic acid (PFOS), perfluorododecanoic acid (PFDoDA), perfluorotridecanoic acid (PFTrDA) and perfluorooctanesulfonamide (FOSA). PFAS profiles did not vary significantly by location, body condition, or life history. Notably, significant positive correlations were observed within respective PFAS and trace elements. However, only negative correlations were evident between these two contaminant types, suggesting different exposure and metabolic pathways. Age-associated concentrations were found for PFTrDA and four trace elements, i.e. silver, mercury, cadmium, selenium, indicating differences in the bioaccumulation biomagnification mechanisms. Overall, our results contribute to global understanding of accumulation of PFAS by offering first insights of PFAS exposure in cetaceans living within South Pacific Australasian waters.
Collapse
Affiliation(s)
- K A Stockin
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, Private Bag 102 904, Auckland 0745, New Zealand.
| | - S Yi
- Department of Chemical and Materials Engineering, University of Auckland, Auckland 1142, New Zealand
| | - G L Northcott
- Northcott Research Consultants Limited, 20 River Oaks Place, Hamilton 3200, New Zealand
| | - E L Betty
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, Private Bag 102 904, Auckland 0745, New Zealand
| | - G E Machovsky-Capuska
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, Private Bag 102 904, Auckland 0745, New Zealand; The Charles Perkins Centre, The University of Sydney, New South Wales, Australia
| | - B Jones
- School of Biological Sciences, University of Auckland, PO Box 92019, Auckland 1142, New Zealand
| | - M R Perrott
- School of Veterinary Science, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand
| | - R J Law
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, Private Bag 102 904, Auckland 0745, New Zealand; Centre for Environment, Fisheries and Aquaculture Science (Cefas), Pakefield Road, Lowestoft, Suffolk NR33 0HT, United Kingdom
| | - A Rumsby
- Department of Chemical and Materials Engineering, University of Auckland, Auckland 1142, New Zealand
| | - M A Thelen
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, Private Bag 102 904, Auckland 0745, New Zealand
| | - L Graham
- AsureQuality Limited, PO Box 31 242, Lower Hutt, New Zealand
| | - E I Palmer
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, Private Bag 102 904, Auckland 0745, New Zealand
| | - L A Tremblay
- School of Biological Sciences, University of Auckland, PO Box 92019, Auckland 1142, New Zealand; Cawthron Institute, Private Bag 2, Nelson 7042, New Zealand
| |
Collapse
|
11
|
Rode KD, Robbins CT, Stricker CA, Taras BD, Tollefson TN. Energetic and health effects of protein overconsumption constrain dietary adaptation in an apex predator. Sci Rep 2021; 11:15309. [PMID: 34321600 PMCID: PMC8319126 DOI: 10.1038/s41598-021-94917-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Accepted: 07/19/2021] [Indexed: 12/02/2022] Open
Abstract
Studies of predator feeding ecology commonly focus on energy intake. However, captive predators have been documented to selectively feed to optimize macronutrient intake. As many apex predators experience environmental changes that affect prey availability, limitations on selective feeding can affect energetics and health. We estimated the protein:fat ratio of diets consumed by wild polar bears using a novel isotope-based approach, measured protein:fat ratios selected by zoo polar bears offered dietary choice and examined potential energetic and health consequences of overconsuming protein. Dietary protein levels selected by wild and zoo polar bears were low and similar to selection observed in omnivorous brown bears, which reduced energy intake requirements by 70% compared with lean meat diets. Higher-protein diets fed to zoo polar bears during normal care were concurrent with high rates of mortality from kidney disease and liver cancer. Our results suggest that polar bears have low protein requirements and that limitations on selective consumption of marine mammal blubber consequent to climate change could meaningfully increase their energetic costs. Although bear protein requirements appear lower than those of other carnivores, the energetic and health consequences of protein overconsumption identified in this study have the potential to affect a wide range of taxa.
Collapse
Affiliation(s)
- Karyn D Rode
- U.S. Geological Survey, Alaska Science Center, 4210 University Drive, Anchorage, AK, 99508, USA.
| | - Charles T Robbins
- School of the Environment and School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA
| | - Craig A Stricker
- U.S. Geological Survey, Fort Collins Science Center, Fort Collins, CO, 80526, USA
| | - Brian D Taras
- Division of Wildlife Conservation, Alaska Department of Fish and Game, Fairbanks, AK, 99701, USA
| | - Troy N Tollefson
- Mazuri Exotic Animal Nutrition, Land O'Lakes, Inc., St. Louis, MO, 63166, USA
| |
Collapse
|
12
|
Becker YA, Fioramonti NE, Dellabianca NA, Riccialdelli L. Feeding ecology of the long finned pilot whale, Globicephala melas edwardii, in the southwestern Atlantic Ocean, determined by stable isotopes analysis. Polar Biol 2021; 44:1655-67. [DOI: 10.1007/s00300-021-02908-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
13
|
Hou R, Chapman CA, Rothman JM, Zhang H, Huang K, Guo S, Li B, Raubenheimer D. The geometry of resource constraint: An empirical study of the golden snub-nosed monkey. J Anim Ecol 2021; 90:751-765. [PMID: 33314075 DOI: 10.1111/1365-2656.13408] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 11/23/2020] [Indexed: 12/29/2022]
Abstract
Apposite conceptualization and measurement of resource variation is critical for understanding many issues in ecology, including ecological niches, persistence and distribution of populations, the structure of communities and population resilience to perturbations. We apply the nutritional geometry framework to conceptualize and quantify the responses of a temperate-living primate, the golden snub-nosed monkey Rhinopithecus roxellana to variation in resource quality and quantity and in nutrient requirements associated with seasonal environments. We present a geometric model distinguishing qualitative constraint, quantitative constraint and 'pseudo-constraint' whereby nutrient intakes resemble response to qualitative resource constraint but are in fact driven by variation in nutrient requirements. The model is applied to analyse nutrient intakes recorded in 164 full-day observations of monkeys from two populations, one wild and the other captive, across seasons. Additionally, we recorded the diet of a single animal over 32 consecutive days in the wild. Despite considerable differences in available resources, the captive and wild populations showed marked similarities in nutrient intakes, including indistinguishable amounts and ratios of ingested macronutrients during summer and autumn and strong year-round maintenance of protein compared to seasonally variable fat and carbohydrate intakes. These similarities suggest homeostatically regulated nutritional targets and provide reference points to identify factors driving population differences in macronutrient intake in winter and spring. Our framework enabled us to distinguish examples of quantitative, qualitative and 'pseudo-constraint'. We suggest that this approach can increase the resolution at which resource constraint is conceptualized and measured in ecological studies.
Collapse
Affiliation(s)
- Rong Hou
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China.,Department of Anthropology, McGill University, Montreal, QC, Canada
| | - Colin A Chapman
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China.,Department of Anthropology, McGill University, Montreal, QC, Canada.,Department of Anthropology, Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC, USA.,School of Life Sciences, University of KwaZulu-Natal, Pietermaritzburg, South Africa
| | - Jessica M Rothman
- Department of Anthropology, Hunter College of the City University of New York, New York, NY, USA
| | - He Zhang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Kang Huang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Songtao Guo
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Baoguo Li
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China.,CAS Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, China
| | - David Raubenheimer
- Charles Perkins Centre and School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| |
Collapse
|
14
|
Lerma M, Dehnhard N, Luna-jorquera G, Voigt CC, Garthe S. Breeding stage, not sex, affects foraging characteristics in masked boobies at Rapa Nui. Behav Ecol Sociobiol 2020; 74. [DOI: 10.1007/s00265-020-02921-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Abstract
Sexual segregation in foraging occurs in some species and populations of boobies (Sulidae), but it is not a general pattern. Sexual segregation in foraging may occur to avoid competition for food, and this competition may intensify during specific stages of breeding. We examined sexual segregation in foraging in relation to breeding stage in masked boobies Sula dactylatra at Rapa Nui by tracking simultaneously incubating and chick-rearing birds using GPS recorders (n = 18) and collected a total of 11 regurgitate samples. Stable isotope analyses (δ13C and δ15N) of whole blood samples were carried out in 20 birds. There were no differences in foraging trip parameters or diet between females and males. Both sexes traveled farther and for longer while incubating than while rearing chicks. Isotopic niches (δ13C and δ15N) overlapped to some degree among all groups at all times, but the lowest overlap between sexes occurred during incubation. While preying on ephemerally distributed flying fish, vertical or horizontal competition avoidance may be almost impossible, and thus females and males share their foraging grounds. Since birds were tracked simultaneously, shorter foraging trips of chick-rearing birds must be an effect of the constraints of provisioning the chick. Differences observed in δ15N and δ13C values between sexes may be caused by subtle differences in their foraging behaviors, or by differences in physiology linked to breeding. Our findings suggest that local oceanography and its inherent food distribution are determinants for sexual segregation in foraging patterns in masked boobies and possibly also other booby species.
Significance statement
In some animals, females and males forage on different areas or prey on different species to avoid competition for food resources. In boobies (Sula sp.), some studies show evidence of sexual segregation in foraging and others do not. Here, we tested if sexual segregation in foraging occurred in masked boobies on the Pacific island of Rapa Nui by studying simultaneously incubating and chick-rearing birds. We found no evidence of sexual segregation on foraging behavior or diet. We discuss that the difference between this and other studies in boobies may be an effect of the local prey availability. When the prey community is more diverse and heterogeneously distributed, each sex may access different resources and thus sexual foraging segregation will occur. In contrast, in areas like Rapa Nui where prey resources are distributed ephemerally, sexual segregation in foraging will not be useful and is thus less likely to occur.
Collapse
|
15
|
Santos RG, Andrades R, Demetrio GR, Kuwai GM, Sobral MF, Vieira JDS, Machovsky-Capuska GE. Exploring plastic-induced satiety in foraging green turtles. Environ Pollut 2020; 265:114918. [PMID: 32544788 DOI: 10.1016/j.envpol.2020.114918] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 05/29/2020] [Accepted: 05/30/2020] [Indexed: 05/10/2023]
Abstract
In the last decade many studies have described the ingestion of plastic in marine animals. While most studies were dedicated to understanding the pre-ingestion processes involving decision-making foraging choices based on visual and olfactory cues of animals, our knowledge in the post-ingestion consequences remains limited. Here we proposed a theoretical complementary view of post-ingestion consequences, attempting to connect plastic ingestion with plastic-induced satiety. We analyzed data of plastic ingestion and dietary information of 223 immature green turtles (Chelonia mydas) from tropical Brazilian reefs in order to understand the impacts of plastic ingestion on foraging behavior. Generalized linear mixing models and permutational analysis of variance suggested that plastic accumulations in esophagus, stomach and intestine differed in their impact on green turtle's food intake. At the initial stages of plastic ingestion, where the plastic still in the stomach, an increase in food intake was observed. The accumulation of plastic in the gastrointestinal tract can reduce food intake likely leading to plastic-induced satiety. Our results also suggest that higher amounts of plastics in the gastrointestinal tract may led to underweight and emaciated turtles. We hope that adopting and refining our proposed framework will help to clarify the post-ingestion consequences of plastic ingestion in wildlife.
Collapse
Affiliation(s)
- Robson G Santos
- Laboratório de Biologia Marinha e Conservação, Universidade Federal de Alagoas, Av. Lourival Melo Mota, s/n, Cidade Universitária, 57072-900, Maceió, AL, Brazil.
| | - Ryan Andrades
- Laboratório de Ictiologia, Universidade Federal do Espírito Santo, Av. Fernando Ferrari, 514, Goiabeiras, 29075-910, Vitória, ES, Brazil
| | - Guilherme Ramos Demetrio
- Laboratório de Ecologia Vegetal, Universidade Federal de Alagoas/Campus Arapiraca - Unidade de Ensino Penedo, Avenida Beira Rio, s/n, Centro Histórico, 57200-000, Penedo, AL, Brazil
| | - Gabriela Miki Kuwai
- Laboratório de Biologia Marinha e Conservação, Universidade Federal de Alagoas, Av. Lourival Melo Mota, s/n, Cidade Universitária, 57072-900, Maceió, AL, Brazil
| | - Mañana Félix Sobral
- Laboratório de Biologia Marinha e Conservação, Universidade Federal de Alagoas, Av. Lourival Melo Mota, s/n, Cidade Universitária, 57072-900, Maceió, AL, Brazil
| | - Júlia de Souza Vieira
- Laboratório de Biologia Marinha e Conservação, Universidade Federal de Alagoas, Av. Lourival Melo Mota, s/n, Cidade Universitária, 57072-900, Maceió, AL, Brazil
| | | |
Collapse
|
16
|
Machovsky-Capuska GE, von Haeften G, Romero MA, Rodríguez DH, Gerpe MS. Linking cadmium and mercury accumulation to nutritional intake in common dolphins (Delphinus delphis) from Patagonia, Argentina. Environ Pollut 2020; 263:114480. [PMID: 32283460 DOI: 10.1016/j.envpol.2020.114480] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 03/04/2020] [Accepted: 03/26/2020] [Indexed: 06/11/2023]
Abstract
Bioaccumulation of Hg and Cd from food is a complex ecological process that has been oversimplified in the past. Common dolphins (Delphinus delphis) provide a powerful model to biomonitor metal concentrations in marine environments worldwide. We combined proportions-based nutritional geometry with metal analysis, stomach content analysis and the proximate composition of prey, to yield novel insights into the accumulation of Hg and Cd. Our analysis showed an age-related accumulation trend for Cd and Hg in kidney and liver, with highest concentrations found at 18 years of age. When viewed through the lens of nutritional ecology, Argentine anchovy (58.1 Mass %) and South American long-finned squid (22.7 Mass %), provided most of the dietary intake of protein (P) and lipids (L) (P:L ratio = 2.6:1.0) and also represented the main source for Cd and Hg levels accumulated in their bodies. This study presents unprecedented evidence on metal accumulation in relation to age and nutritional intake in a marine predator.
Collapse
Affiliation(s)
| | | | - M Alejandra Romero
- Centro de Investigación Aplicada y Transferencia Tecnológica en Recursos Marinos "Almirante Storni", Güemes 1030, San Antonio Oeste, 8520, Rio Negro, Argentina; Escuela Superior de Ciencias Marinas, Universidad Nacional del Comahue, San Martín 247, San Antonio Oeste, Rio Negro, Argentina
| | - Diego H Rodríguez
- Instituto de Investigaciones Marinas y Costeras, Departamento de Ciencias Marinas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, CONICET, Funes 3350, Mar del Plata, B7602AYL, Argentina; Laboratorio de Mamíferos Marinos, Departamento de Ciencias Marinas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Mar del Plata, Argentina
| | - Marcela S Gerpe
- Instituto de Investigaciones Marinas y Costeras, Departamento de Ciencias Marinas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, CONICET, Funes 3350, Mar del Plata, B7602AYL, Argentina; Laboratorio de Ecotoxicología, Departamento de Ciencias Marinas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Mar del Plata, Argentina
| |
Collapse
|
17
|
Soledade Lemos L, Burnett JD, Chandler TE, Sumich JL, Torres LG. Intra‐ and inter‐annual variation in gray whale body condition on a foraging ground. Ecosphere 2020. [DOI: 10.1002/ecs2.3094] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Leila Soledade Lemos
- Geospatial Ecology of Marine Megafauna Lab Marine Mammal Institute, Fisheries and Wildlife Department Oregon State University Corvallis Oregon 97331 USA
| | - Jonathan D. Burnett
- Aerial Information Systems Laboratory Forest Engineering, Resources and Management Department Oregon State University Corvallis Oregon 97331 USA
| | - Todd E. Chandler
- Geospatial Ecology of Marine Megafauna Lab Marine Mammal Institute, Fisheries and Wildlife Department Oregon State University Corvallis Oregon 97331 USA
| | - James L. Sumich
- Fisheries and Wildlife Department Oregon State University Corvallis Oregon 97331 USA
| | - Leigh G. Torres
- Geospatial Ecology of Marine Megafauna Lab Marine Mammal Institute, Fisheries and Wildlife Department Oregon State University Corvallis Oregon 97331 USA
| |
Collapse
|
18
|
Morimoto J, Lihoreau M. Open Data for Open Questions in Comparative Nutrition. Insects 2020; 11:E236. [PMID: 32283710 DOI: 10.3390/insects11040236] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 04/02/2020] [Accepted: 04/07/2020] [Indexed: 11/26/2022]
Abstract
Achieving a better understanding of the consequences of nutrition to animal fitness and human health is a major challenge of our century. Nutritional ecology studies increasingly use nutritional landscapes to map the complex interacting effects of nutrient intake on animal performances, in a wide range of species and ecological contexts. Here, we argue that opening access to these hard-to-obtain, yet considerably insightful, data is fundamental to develop a comparative framework for nutrition research and offer new quantitative means to address open questions about the ecology and evolution of nutritional processes.
Collapse
|
19
|
Machovsky-Capuska GE, Andrades R, Santos RG. Debris ingestion and nutritional niches in estuarine and reef green turtles. Mar Pollut Bull 2020; 153:110943. [PMID: 32056851 DOI: 10.1016/j.marpolbul.2020.110943] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 01/23/2020] [Accepted: 01/26/2020] [Indexed: 06/10/2023]
Abstract
Little attention has been drawn toward the effects of marine debris ingestion in relation to nutrient acquisition and fitness consequences. We tested whether anthropogenic debris ingestion influence the nutritional niches of endangered green turtles (Chelonia mydas) in estuarine and reef habitats on the Brazilian coast. Our results showed that estuarine turtles consumed diets with lower proportional wet mass composition of protein (P) and water (W) than their reef conspecifics. The amounts of debris, mostly plastics, retrieved from the digestive tracts of estuarine turtles were higher compared with those individuals from reefs. The realized nutritional niche from estuarine turtles was subject to the debris density in the environment, lack of benthic food resources available and the surface foraging behavior, likely preventing them from reaching their nutritional goals and resulting in lower fitness. The study provides critical information for the management and conservation of ecologically threatened individuals, populations, and their natural habitats.
Collapse
Affiliation(s)
| | - Ryan Andrades
- Departamento de Oceanografia e Ecologia, Universidade Federal do Espírito Santo, Av. Fernando Ferrari, 514, 29075-910 Vitória, ES, Brazil
| | - Robson Guimarães Santos
- Instituto de Ciências Biológicas e da Saúde, Universidade Federal de Alagoas, Av. Lourival Melo Mota, s/n, Cidade Universitária, 57072-900 Maceió, AL, Brazil
| |
Collapse
|
20
|
Alves F, Dromby M, Baptista V, Ferreira R, Correia AM, Weyn M, Valente R, Froufe E, Rosso M, Sousa-Pinto I, Dinis A, Dias E, Teodósio MA. Ecophysiological traits of highly mobile large marine predators inferred from nucleic acid derived indices. Sci Rep 2020; 10:4752. [PMID: 32179865 PMCID: PMC7075925 DOI: 10.1038/s41598-020-61769-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 02/26/2020] [Indexed: 11/28/2022] Open
Abstract
Nucleic acid-derived indices such as RNA/DNA ratios have been successfully applied as ecophysiological indicators to assess growth, nutritional condition and health status in marine organisms given that they provide a measure of tissue protein reserves, which is known to vary depending on changes in the environment. Yet, the use of these biochemical indices on highly mobile large predators is scarce. In this study, we tested the applicability of using nucleic acids to provide insights on the ecophysiological traits of two marine mammal species (common bottlenose dolphins and short-finned pilot whales) and explored potential related factors (species, sex, season, and residency pattern), using skin tissue (obtained from biopsy darts) of apparently healthy and adult free-ranging animals. Significantly higher RNA/DNA ratios were obtained for bottlenose dolphins (p < 0.001), and for visitor pilot whales when compared with resident pilot whales (p = 0.001). No significant changes were found between the sexes. Based on the percentile approach, the samples contain individuals in a general good condition (as the 10th percentile is not closer to the mean than the 75th percentile), suggesting that the studied region of Macaronesia may be considered an adequate habitat. The combination of this effective tool with genetic sexing and photographic-identification provided an overall picture of ecosystem health, and although with some limitations and still being a first approach, it has the applicability to be used in other top predators and ecosystems.
Collapse
Affiliation(s)
- F Alves
- MARE - Marine and Environmental Sciences Centre, ARDITI, Madeira, Portugal. .,OOM - Oceanic Observatory of Madeira, Funchal, Portugal.
| | - M Dromby
- OOM - Oceanic Observatory of Madeira, Funchal, Portugal.,Faculty of Sciences and Technology, Universidade do Algarve, Campus de Gambelas, Faro, Portugal
| | - V Baptista
- CCMAR - Centre of Marine Sciences, Universidade do Algarve, Campus de Gambelas, Faro, Portugal
| | - R Ferreira
- MARE - Marine and Environmental Sciences Centre, ARDITI, Madeira, Portugal.,OOM - Oceanic Observatory of Madeira, Funchal, Portugal
| | - A M Correia
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Matosinhos, Portugal.,Department of Biology, Faculty of Sciences, University of Porto - FCUP, Porto, Portugal
| | - M Weyn
- OOM - Oceanic Observatory of Madeira, Funchal, Portugal.,Marine Biology Research Group, Ghent University, Ghent, Belgium
| | - R Valente
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Matosinhos, Portugal.,Department of Biology, Faculty of Sciences, University of Porto - FCUP, Porto, Portugal
| | - E Froufe
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Matosinhos, Portugal
| | - M Rosso
- CIMA Research Foundation, Savona, Italy
| | - I Sousa-Pinto
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Matosinhos, Portugal.,Department of Biology, Faculty of Sciences, University of Porto - FCUP, Porto, Portugal
| | - A Dinis
- MARE - Marine and Environmental Sciences Centre, ARDITI, Madeira, Portugal.,OOM - Oceanic Observatory of Madeira, Funchal, Portugal
| | - E Dias
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Matosinhos, Portugal
| | - M A Teodósio
- Faculty of Sciences and Technology, Universidade do Algarve, Campus de Gambelas, Faro, Portugal.,CCMAR - Centre of Marine Sciences, Universidade do Algarve, Campus de Gambelas, Faro, Portugal
| |
Collapse
|