Human disturbance increases trophic niche overlap in terrestrial carnivore communities

Proceedings of the National Academy of Sciences, Journal Year: 2020, Volume and Issue: 117(43), P. 26842 - 26848

Published: Oct. 12, 2020

Significance Niche theory posits that species must limit overlap in the use of space, time, or resources to minimize competition. However, human disturbances are rapidly altering ecosystems with uncertain consequences for niche partitioning. Dietary partitioning is primary way many interspecific competition, and it particularly important carnivores because diet can trigger interference competition killing. We used stable isotope analyses examine carnivore diets across Great Lakes region United States show inhabiting disturbed consume more foods, leading significant increases both breadth dietary among competing species. These results suggest human-dominated landscapes experience conflict due consumption food subsidies.

Language: Английский

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Intrapopulation niche partitioning in a generalist predator limits food web connectivity

Ecology, Journal Year: 2009, Volume and Issue: 90(8), P. 2263 - 2274

Published: July 24, 2009

Predators are increasingly recognized as key elements in food webs because of their ability to link the fluxes nutrients and energy between spatially separated chains. However, context web connectivity, predator populations have been mainly treated homogeneous units, despite compelling evidence individual specialization resource use. It is conceivable that individuals a predatory species use different resources associated with chains, thereby decoupling cross-habitat linkages. We tested whether intrapopulation differences habitat generalist freshwater Eurasian perch (Perca fluviatilis) led long-term niche partitioning affected degree ecological coupling. evaluated trophic variability at successively larger timescales by analyzing gut contents stable isotopes (delta13C delta15N) liver muscle, tissues provide longer integration activity. found distinct habitats pelagic littoral subpopulations, consistent through various timescales. Pelagic fish showed narrower niche, lower specialization, more behavior than fish, could be expected from inhabiting relatively less diverse environment. This result indicated substantial reduction occur subpopulation level, provides fewer chances specialization. limits predators In addition, we suggest quantitative, standardized approach based on measure coupling mediated top predator.

Language: Английский

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Quantifying Inter- and Intra-Population Niche Variability Using Hierarchical Bayesian Stable Isotope Mixing Models

PLoS ONE, Journal Year: 2009, Volume and Issue: 4(7), P. e6187 - e6187

Published: July 8, 2009

Variability in resource use defines the width of a trophic niche occupied by population. Intra-population variability may occur across hierarchical levels population structure from individuals to subpopulations. Understanding how organization contribute is critical ecology and evolution. Here we describe stable isotope mixing model that can simultaneously estimate both prey composition consumer diet among organization. By explicitly estimating variance components for multiple scales, deconstruct into relevant structure. We apply this new approach data gray wolves coastal British Columbia, show support extensive intra-population individuals, social groups, geographically isolated The analytic method improves models accounting variability, analysis quantitatively assessing contribution

Language: Английский

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Invasions and niche width: does niche width of an introduced crayfish differ from a native crayfish?

Freshwater Biology, Journal Year: 2009, Volume and Issue: 54(8), P. 1731 - 1740

Published: April 23, 2009

Summary 1. Human activities have promoted the spread of species worldwide. Several crayfish been introduced into new areas, posing a threat to native and other biota. Invader success may depend on ability utilise wide variety habitats resources. Successful invaders are generally expected broader niches be more plastic than non‐invasive species. 2. Using stable isotope ratios carbon nitrogen we compared niche widths noble signal crayfish, successful invader Swedish streams. The calculation width took account between‐site differences in basal resource signature ranges. We also assessed whether population density, prey biomass or diversity affected width. 3. At level, had twice crayfish. However, individual populations streams similar widths. This suggests that has greater plasticity with respect habitat utilisation feeding Niche both correlated positively benthic invertebrate diversity, indicating animal food sources important for 4. find assessing relation can useful tool trying predict impact invasions different scales. findings this study suggest natives will stream scale whereas larger regional due wider range

Language: Английский

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Characterizing trophic ecology of generalist consumers: a case study of the invasive lionfish in The Bahamas

Marine Ecology Progress Series, Journal Year: 2011, Volume and Issue: 448, P. 131 - 141

Published: Nov. 23, 2011

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 448:131-141 (2012) - DOI: https://doi.org/10.3354/meps09511 Characterizing trophic ecology of generalist consumers: a case study invasive lionfish in The Bahamas Craig A. Layman1,*, Jacob E. Allgeier2 1Marine Sciences Program, Florida International University, 3000 N.E. 151st St., North Miami, 33181, USA 2Odum School Ecology, University Georgia, Athens, Georgia 30602, *Email: [email protected] ABSTRACT: Population sizes consumers are increasing many ecosystems because various human activities, and it is critical understand role these species if we predict how they may affect food web structure ecosystem function. Lionfish Pterois volitans/miles have spread throughout Western Atlantic Gulf Mexico significant effects on native faunal communities. We characterized back reef habitats Abaco Island, Bahamas, drawing recently developed analytical tools that employ both direct diet information stable isotope data. Although δ15N δ13C bi-plot data appeared suggest substantial niche overlap with gray snapper schoolmaster snapper, Bayesian suggested differences core isotopic niches among species. This was consistent information, as fed almost exclusively small prey fishes more commonly crustaceans. When combining empirical simulation model, individual appear be specialized their diets than snapper. this pattern driven by high site-fidelity lionfish, conjunction distinct assemblages at patch scale. widely considered predators, reveal aspects generality must invaded continues examined. KEY WORDS: Food · Individual specialization Invasive Optimal foraging Predator-prey interaction volitans miles Full text pdf format PreviousNextCite article as: Layman CA, Allgeier JE Bahamas. Mar Ecol Prog Ser 448:131-141. Export citation Tweet linkedIn Cited Published Vol. 448. Online publication date: February 23, 2012 Print ISSN: 0171-8630; 1616-1599 Copyright © Inter-Research.

Language: Английский

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Landscape heterogeneity and marine subsidy generate extensive intrapopulation niche diversity in a large terrestrial vertebrate

Journal of Animal Ecology, Journal Year: 2008, Volume and Issue: 78(1), P. 126 - 133

Published: Sept. 26, 2008

1. Inquiries into niche variation within populations typically focus on proximate ecological causes such as competition. Here we examine how landscape heterogeneity and allochthonous (marine) subsidy might ultimately generate intrapopulation diversity. 2. Using stable isotope analysis, detected extensive terrestrial-marine isotopic among subpopulations, social groups, individual grey wolves (Canis lupus) that occupy a spatially heterogeneous in coastal British Columbia comprising mainland area adjacent archipelago. 3. The inner island subpopulation exhibited the widest population, consuming terrestrial marine resources. Mainland outer subpopulations occupied comparatively narrow primarily terrestrial, marine, niches respectively. Within these biogeographical groups also diverged niche. 4. To support examination at level, used an approach to test Van Valen's (1965) hypothesis. Consistent with hypothesis, observed among-individual increased width. 5. Patterns all levels related structured competitive environment, which turn mediated availability use of Broadly, our results suggest spatial subsidy--both widespread but commonly subject contemporary anthropogenic change--might provide novel opportunities for conservation populations.

Language: Английский

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Food web structure and body size: trophic position and resource acquisition

Oikos, Journal Year: 2009, Volume and Issue: 119(1), P. 147 - 153

Published: Nov. 27, 2009

Language: Английский

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Quantifying the multiple facets of isotopic diversity: New metrics for stable isotope ecology

Ecological Indicators, Journal Year: 2015, Volume and Issue: 56, P. 152 - 160

Published: May 15, 2015

Language: Английский

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Tissue Turnover Rates and Isotopic Trophic Discrimination Factors in the Endothermic Teleost, Pacific Bluefin Tuna (Thunnus orientalis)

PLoS ONE, Journal Year: 2012, Volume and Issue: 7(11), P. e49220 - e49220

Published: Nov. 7, 2012

Stable isotope analysis (SIA) of highly migratory marine pelagic animals can improve understanding their patterns and trophic ecology. However, accurate interpretation isotopic analyses relies on knowledge turnover rates tissue-diet discrimination factors. Laboratory-derived factors have been difficult to obtain due the challenges maintaining these species in captivity. We conducted a study determine tissue- (white muscle liver) isotope- (nitrogen carbon) specific (TDFs) using archived tissues from captive Pacific bluefin tuna (PBFT), Thunnus orientalis, 1–2914 days after diet shift Half-life values for 15N white liver were 167 86 days, 13C 255 162 respectively. TDFs 1.9 1.1‰ δ15N 1.8 1.2‰ δ13C, Our results demonstrate that is well described by single compartment first-order kinetics model. report variability between tissue types dynamics, hypothesize metabolic processes play large role nitrogen carbon PBFT tissues. showed most predictable change with over time, suggesting data may provide reliable inferences migration studies stable isotopes wild fish. These allow more field dramatically our ability use tunas better understand

Language: Английский

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Dietary niche overlap in a nearshore elasmobranch mesopredator community

Marine Ecology Progress Series, Journal Year: 2010, Volume and Issue: 425, P. 247 - 260

Published: Dec. 28, 2010

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 425:247-260 (2011) - DOI: https://doi.org/10.3354/meps08988 Dietary niche overlap in a nearshore elasmobranch mesopredator community Jeremy J. Vaudo*, Michael R. Heithaus Science Program, Department of Biological Sciences, Florida International University, 3000 NE 151 Street, North Miami, 33181, USA *Email: [email protected] ABSTRACT: Understanding trophic interactions is crucial understanding dynamics food webs because mesopredators provide link between apex predators and lower levels. Using stable isotopic analysis stomach content analysis, we examined dietary within diverse Shark Bay, Western Australia. Isotopic values (δ13C δ15N) were consistent with most species being highly dependent on seagrass-based web. Differences observed mean species, but there was great deal space used by when at level individuals. Stomach contents also suggest among diets Himantura spp. Glaucostegus typus, which contained many same prey primarily crustaceans typically associated seagrass habitats, although different proportions. Diet data that, despite having similar other Pastinachus atrus appears feed sandflat-associated species. In this community, variation groups examined, possibly due individual specialization, result high resource may be key component allowing for diversity system perhaps role dynamics. KEY WORDS: Stable isotope · Resource partitioning Individual specialization Stingray Batoid Elasmobranch Full text pdf format PreviousNextCite article as: Vaudo JJ, MR community. Mar Ecol Prog Ser 425:247-260. Export citation Tweet linkedIn Cited Published Vol. 425. Online publication date: March 14, 2011 Print ISSN: 0171-8630; 1616-1599 Copyright © Inter-Research.

Language: Английский

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