scholarly journals Inter-population differences in coyote diet and niche width along an urban–suburban–rural gradient

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Scott Sugden ◽  
Maureen Murray ◽  
Mark A Edwards ◽  
Colleen Cassady St. Clair
Keyword(s):  
Isotope Analysis ◽  
Niche Width ◽  
Food Sources ◽  
Spatial And Temporal Variation ◽  
Model Parameters ◽  
Generalist Species ◽  
Methodological Choices ◽  
Dietary Niche ◽  
Anthropogenic Food ◽  
Urban Coyotes

Abstract Many generalist species thrive in urban environments by supplementing their diets with anthropogenic food, which creates numerous challenges for managing urban wildlife. Management could be advanced with more information on how spatial and temporal variation in habitat use by urban animals predicts variation in their dietary ecology. In this study, we used stable isotope analysis complemented with GPS collar location data to determine how diet composition and the dietary niche of coyotes (Canis latrans) varied across a sample of 169 individuals collected along an urban-to-rural gradient in Alberta, Canada. We further categorized urban individuals as either matrix (frequent use of developed areas) or greenspace (use of natural areas) via GPS locations. Matrix coyotes were isotopically distinct from all other coyote populations: they had the largest dietary niche, exhibited the most among-individual variation in diet, consumed the most anthropogenic food and fruit, and consumed the least amount of prey. Greenspace coyotes consumed more anthropogenic food than rural and suburban coyotes but otherwise exhibited similar niche width, among-individual heterogeneity, and prey consumption. We further tested for seasonal dietary variation and found that urban coyotes had a larger dietary niche during the summer, when they also consumed more anthropogenic food. Our conclusions were robust to our choice of mixing model parameters, including discrimination factors, suggesting that these methodological choices have limited effect when discerning relative trends among populations. Overall, our results suggest that management of urban coyotes should target the food sources accessible to coyotes in the urban matrix to reduce human–coyote conflict.

scholarly journals An altered microbiome in urban coyotes mediates relationships between anthropogenic diet and poor health

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Scott Sugden ◽  
Dana Sanderson ◽  
Kyra Ford ◽  
Lisa Y. Stein ◽  
Colleen Cassady St. Clair
Keyword(s):  
Habitat Use ◽  
Body Condition ◽  
Isotope Analysis ◽  
Food Sources ◽  
Rrna Gene ◽  
Generalist Species ◽  
Fecal Microbiome ◽  
Microbiome Composition ◽  
Anthropogenic Food ◽  
Urban Coyotes

AbstractGeneralist species able to exploit anthropogenic food sources are becoming increasingly common in urban environments. Coyotes (Canis latrans) are one such urban generalist that now resides in cities across North America, where diseased or unhealthy coyotes are frequently reported in cases of human-wildlife conflict. Coyote health and fitness may be related to habitat use and diet via the gut microbiome, which has far-reaching effects on animal nutrition and physiology. In this study, we used stomach contents, stable isotope analysis, 16S rRNA gene amplicon sequencing, and measures of body condition to identify relationships among habitat use, diet, fecal microbiome composition, and health in urban and rural coyotes. Three distinct relationships emerged: (1) Urban coyotes consumed more anthropogenic food, which was associated with increased microbiome diversity, higher abundances of Streptococcus and Enterococcus, and poorer average body condition. (2) Conversely, rural coyotes harbored microbiomes rich in Fusobacteria, Sutterella, and Anaerobiospirillum, which were associated with protein-rich diets and improved body condition. (3) Diets rich in anthropogenic food were associated with increased abundances of Erysipelotrichiaceae, Lachnospiraceae, and Coriobacteriaceae, which correlated with larger spleens in urban coyotes. Urban coyotes also had an increased prevalence of the zoonotic parasite Echinococcus multilocularis, but there were no detectable connections between parasite infection and microbiome composition. Our results demonstrate how the consumption of carbohydrate-rich anthropogenic food by urban coyotes alters the microbiome to negatively affect body condition, with potential relationships to parasite susceptibility and conflict-prone behavior.

scholarly journals Diet assessments as a tool to control invasive species: comparison between Monk and Rose-ringed parakeets with stable isotopes

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
N A Borray-Escalante ◽  
D Mazzoni ◽  
A Ortega-Segalerva ◽  
L Arroyo ◽  
V Morera-Pujol ◽  
...  
Keyword(s):  
Invasive Species ◽  
Isotope Analysis ◽  
Control Measures ◽  
Food Sources ◽  
Effective Control ◽  
Limiting Factor ◽  
Δ13c And Δ15n ◽  
Isotopic Signatures ◽  
Monk Parakeet ◽  
Anthropogenic Food

Abstract Food is a main limiting factor for most populations. As a consequence, knowledge about the diet of invasive alien species determines the design of control measures. The Monk and Rose-ringed parakeets are two typical species of successful invasive parrots that are highly appreciated by people. Although some observations suggest that Monk parakeets rely on a higher percentage of anthropogenic food than Rose-ringed parakeets, no detailed quantitative data is available. The aim of this study was to compare the diet of the two parakeets using stable isotope analysis (SIA). We performed SIA of carbon and nitrogen in feathers collected in Barcelona, Spain. We also measured isotopic ratios for potential food sources. We reconstructed the diet of parakeets using Bayesian mixing models. The two species differed in the isotopic signatures of their feathers for both δ13C and δ15N. Diet reconstruction showed that Monk parakeets feed mainly on anthropogenic food (41.7%), herbaceous plants (26.9%) and leaves/seeds (22.2%), while Rose-ringed parakeets feed mainly on flowers/fruits (44.1%), anthropogenic food provided in the trap located at the museum (32.4%) and leaves/seeds (23.1%). The more detailed information we can obtain from the diet of these species is useful to develop more effective control measures for their populations. The Monk parakeet may be more susceptible to control through education local residents, given the greater use of anthropogenic food in this species compared to Rose-ringed parakeet. Our conclusions also indicate that SIA is a powerful tool in providing crucial information about the diet and informing measures to control invasive species.

Food sources for the bivalve Corbicula japonica in the foremost fishing lakes estimated from stable isotope analysis

2006 ◽  
Vol 72 (1) ◽  
pp. 105-114 ◽  
Author(s):  
Akihide KASAI ◽  
Haruhiko TOYOHARA ◽  
Akiko NAKATA ◽  
Tsunehiro MIURA ◽  
Nobuyuki AZUMA
Keyword(s):  
Stable Isotope ◽  
Stable Isotope Analysis ◽  
Isotope Analysis ◽  
Food Sources ◽  
Corbicula Japonica

Food sources of the pearl oyster in coastal ecosystems of Japan: Evidence from diet and stable isotope analysis

2008 ◽  
Vol 76 (3) ◽  
pp. 704-709 ◽  
Author(s):  
Kayoko Fukumori ◽  
Misa Oi ◽  
Hideyuki Doi ◽  
Noboru Okuda ◽  
Hitomi Yamaguchi ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Stable Isotope Analysis ◽  
Isotope Analysis ◽  
Pearl Oyster ◽  
Coastal Ecosystems ◽  
Food Sources

Stable isotope analysis reveals partitioning in prey use by Kajikia audax (Istiophoridae), Thunnus albacares, Katsuwonus pelamis, and Auxis spp. (Scombridae) in the Eastern Tropical Pacific of Ecuador

2021 ◽  
Vol 19 (4) ◽  
Author(s):  
Rigoberto Rosas-Luis ◽  
Nancy Cabanillas-Terán ◽  
Carmen A. Villegas-Sánchez
Keyword(s):  
Stable Isotope ◽  
Food Web ◽  
Stable Isotope Analysis ◽  
Trophic Ecology ◽  
Isotope Analysis ◽  
Middle Level ◽  
Food Sources ◽  
Thunnus Albacares ◽  
Katsuwonus Pelamis ◽  
Δ13c And Δ15n

Abstract Kajikia audax, Thunnus albacares, Katsuwonus pelamis, and Auxis spp. occupy high and middle-level trophic positions in the food web. They represent important sources for fisheries in Ecuador. Despite their ecological and economic importance, studies on pelagic species in Ecuador are scarce. This study uses stable isotope analysis to assess the trophic ecology of these species, and to determine the contribution of prey to the predator tissue. Isotope data was used to test the hypothesis that medium-sized pelagic fish species have higher δ15N values than those of the prey they consumed, and that there is no overlap between their δ13C and δ15N values. Results showed higher δ15N values for K. audax, followed by T. albacares, Auxis spp. and K. pelamis, which indicates that the highest position in this food web is occupied by K. audax. The stable isotope Bayesian ellipses demonstrated that on a long time-scale, these species do not compete for food sources. Moreover, δ15N values were different between species and they decreased with a decrease in predator size.

scholarly journals Morphology and stable isotope analysis demonstrate different structuring of bat communities in rainforest and savannah habitats

2018 ◽  
Vol 5 (12) ◽  
pp. 180849 ◽  
Author(s):  
Ara Monadjem ◽  
Adam Kane ◽  
Peter Taylor ◽  
Leigh R. Richards ◽  
Grant Hall ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Stable Isotope Analysis ◽  
Niche Breadth ◽  
Isotope Analysis ◽  
Morphological Characters ◽  
Trophic Levels ◽  
Species Packing ◽  
Dietary Niche ◽  
The One ◽  
Ellipse Area

Bats play important ecological roles in tropical systems, yet how these communities are structured is still poorly understood. Our study explores the structure of African bat communities using morphological characters to define the morphospace occupied by these bats and stable isotope analysis to define their dietary niche breadth. We compared two communities, one in rainforest (Liberia) and one in savannah (South Africa), and asked whether the greater richness in the rainforest was due to more species ‘packing’ into the same morphospace and trophic space than bats from the savannah, or some other arrangement. In the rainforest, bats occupied a larger area in morphospace and species packing was higher than in the savannah; although this difference disappeared when comparing insectivorous bats only. There were also differences in morphospace occupied by different foraging groups (aerial, edge, clutter and fruitbat). Stable isotope analysis revealed that the range of δ 13 C values was almost double in rainforest than in savannah indicating a greater range of utilization of basal C 3 and C 4 resources in the former site, covering primary productivity from both these sources. The ranges in δ 15 N, however, were similar between the two habitats suggesting a similar number of trophic levels. Niche breadth, as defined by either standard ellipse area or convex hull, was greater for the bat community in rainforest than in savannah, with all four foraging groups having larger niche breadths in the former than the latter. The higher inter-species morphospace and niche breadth in forest bats suggest that species packing is not necessarily competitive. By employing morphometrics and stable isotope analysis, we have shown that the rainforest bat community packs more species in morphospace and uses a larger niche breadth than the one in savannah.

scholarly journals From wetland specialist to hand-fed generalist: shifts in diet and condition with provisioning for a recently urbanized wading bird

2018 ◽  
Vol 373 (1745) ◽  
pp. 20170100 ◽  
Author(s):  
Maureen H. Murray ◽  
Anjelika D. Kidd ◽  
Shannon E. Curry ◽  
Jeffrey Hepinstall-Cymerman ◽  
Michael J. Yabsley ◽  
...  
Keyword(s):  
Urban Areas ◽  
Isotope Analysis ◽  
Protein Body ◽  
South Florida ◽  
High Mass ◽  
Urban Habitat ◽  
Resource Subsidies ◽  
Wading Bird ◽  
Trade Offs ◽  
Anthropogenic Food

Many wildlife species shift their diets to use novel resources in urban areas. The consequences of these shifts are not well known, and consumption of reliable—but low quality—anthropogenic food may present important trade-offs for wildlife health. This may be especially true for carnivorous species such as the American white ibis ( Eudocimus albus ), a nomadic wading bird which has been increasingly observed in urban parks in South Florida, USA. We tested the effects of anthropogenic provisioning on consumer nutrition (i.e. dietary protein), body condition and ectoparasite burdens along an urban gradient using stable isotope analysis, scaled mass index values and GPS transmitter data. Ibises that assimilated more provisioned food were captured at more urban sites, used more urban habitat, had lower mass–length residuals, lower ectoparasite scores, assimilated less δ 15N and had smaller dietary isotopic ellipses. Our results suggest that ibises in urban areas are heavily provisioned with anthropogenic food, which appears to offer a trade-off by providing low-quality, but easily accessible, calories that may not support high mass but may increase time available for anti-parasite behaviours such as preening. Understanding such trade-offs is important for investigating the effects of provisioning on infection risk and the conservation of wildlife in human-modified habitats. This article is part of the theme issue ‘Anthropogenic resource subsidies and host–parasite dynamics in wildlife’.

scholarly journals Trophodynamics at the Longqi hydrothermal vent field and comparison with the East Scotia and Central Indian Ridges

2020 ◽  
Vol 167 (10) ◽  
Author(s):  
W. D. K. Reid ◽  
B. D. Wigham ◽  
L. Marsh ◽  
J. N. J. Weston ◽  
Y. Zhu ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Hydrothermal Vent ◽  
Hydrothermal Vents ◽  
Trophic Ecology ◽  
Tricarboxylic Acid Cycle ◽  
Isotope Analysis ◽  
Southwest Indian Ridge ◽  
Food Sources ◽  
Model Based Clustering ◽  
Indian Ridge

Abstract The Longqi vent field, situated on the Southwest Indian Ridge, is ecologically distinct among known hydrothermal vents fields. It hosts a combination of previously unknown species and those shared at species or genus level with other hydrothermal vents on the Central Indian Ridge (CIR) and East Scotia Ridge (ESR). We investigate the size-based and trophodynamics of consumers at Longqi vent field and compared these with ESR and CIR vent fields using stable isotope analysis. Intra-specific variability in δ13C and δ15N values in relationship to shell length was observed in Gigantopelta aegis but absent in Chrysomallon squamiferum. A model-based clustering approach identified four trophic groupings at Longqi: species with the lowest δ13C values being supported by carbon fixed via the Calvin–Benson–Bassham cycle, the highest δ13C values being supported by the reductive tricarboxylic acid cycle and intermediate values potentially supported by a mix of these primary production sources. These clusters were driven by potential differences in resource partitioning. There were also differences in the spread of stable isotope values at the vent field level when comparing Bayesian stable isotope ellipse areas among Longqi, CIR and ESR vent fields. This was driven by a combination of the range in δ13C value of macrofauna, and the negative δ15N values which were only observed at Longqi and CIR vent fields. Many of the shared species or genera showed inter-vent field differences in stable isotope values which may be related to site-specific differences in food sources, geochemistry or potential intra-field competition. This study provides important information on the trophic ecology of hydrothermal vent macrofauna found within an area of seabed that is licensed for seabed mining exploration.

Swan grazing on seagrass: abundance but not grazing pressure varies over an annual cycle in a temperate estuary

2014 ◽  
Vol 65 (8) ◽  
pp. 738 ◽  
Author(s):  
Gary E. Choney ◽  
Kathryn McMahon ◽  
Paul S. Lavery ◽  
Neil Collier
Keyword(s):  
Annual Cycle ◽  
River Estuary ◽  
Grazing Pressure ◽  
Food Sources ◽  
Spatial And Temporal Variation ◽  
Human Disturbances ◽  
Black Swans ◽  
New Findings ◽  
Cycle Maximum ◽  
Negative Effect

Herbivorous waterfowl such as black swans are significant grazers in temperate waterbodies; their abundance, distribution and grazing rates vary over seasonal cycles. The present study examined spatial and temporal variation in the abundance and grazing rates of black swans in the Lower Swan River estuary, Western Australia, using visual surveys over 1 year (2009), and potential drivers of this variation, food sources and disturbance factors were assessed. We predicted that swan abundance and grazing pressure would be greater in summer and autumn when seasonal wetlands dry and the abundance of food sources would positively influence their distribution, whereas the level of disturbance would have a negative effect. Plant–grazer interactions are dynamic and complex; the present study revealed new findings on the seasonality of this relationship, where swan abundance but not grazing pressure varied over an annual cycle. Maximum swan abundance occurred in autumn (185) with minima in spring (53) but the swan grazing pressure did not vary between seasons, ranging from 6% to 25% of seagrass production consumed. Swan abundance was a function of season and the cover of seagrass. Key hot spots for swan abundance were identified where management efforts could be targeted by minimising human disturbances and protecting seagrass.

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