Coyotes

Contributed Paper
ROOM: HCCC, Room 19
SESSION NUMBER: 92
 

12:50PM Urbanization and Its Effects on Resource Use in Coyotes in Southern California
Rachel N. Larson; Justin L. Brown; Seth P. D. Riley; Tim J. Karels
As humans increasingly develop and inhabit urban areas, the number of species coming into contact with us is increasing. In addition, urbanization can change the distribution and availability of resources. The increased availability of anthropogenic resources is an often cited but poorly understood mechanism believed to attract and sustain wildlife populations in cities. Southern California is one of the largest urban areas in the United States, yet populations of mammalian carnivores, such as coyotes (Canis latrans), still persist there. Studying the diet of urban coyotes will help us understand how these carnivores colonize and persist in human-dominated landscapes and how they influence urban ecosystems. Our goal is to describe the diet of coyotes living in the urban areas of Los Angeles and draw comparisons to surrounding suburban Thousand Oaks and rural agricultural areas. We collected scat data from 47 transects to assess population-level trends and whiskers from 19 collared individuals and 44 carcasses for stable isotope analysis. Anthropogenic items are a common occurrence in urban coyote scats (63% of scats). This is in contrast to the suburban population, where the occurrence of natural prey items is far more common (79% of scats) compared to anthropogenic items (42% of scats). On an individual level, coyotes are segregated by their stable isotope values, with urban coyotes consuming mostly anthropogenic foods, rural coyotes consuming mostly natural foods, and suburban coyotes exhibiting greater variation in isotope signatures. Individuals are also variable within their own isotope signatures: some express high amounts of intra-individual variation and others low amounts. This suggests that some individuals are specializing on particular resources and others maintaining a generalist diet. Increasing our knowledge of urban coyotes will furthering our understanding their role within urban ecosystems while also informing wildlife biologists on the best steps to reduce human-coyote conflict.
1:10PM Genetic Aspects of Boldness and Aggression in Urban Coyotes
Ashley Wurth; Jean Dubach; Stanley Gehrt
Animal behavior has been linked to hormones, neurotransmitters, gene expression, and gene regions. Serotonin, dopamine, and androgen-linked gene regions impact emotions and behaviors such as aggression, boldness, anxiety, and activity. However, behavioral-genetic linkages have been mainly researched in people, domestic animals such as dogs (Canis lupus familiaris), birds, or in a lab setting. Our objective was to determine if gene-behavior linkages described in dogs, particularly for boldness or aggression, also occur within an urban population of coyotes (Canis latrans). We captured, analyzed behavior, and genotyped over 100 coyotes in the Chicago Metropolitan Area during 2014-2017. We recorded behavior in 5 different contexts (3 field and 2 lab), including behavioral actions from trapped coyotes while 1) people were seen by a coyote at a distance, 2) when a person approached the edge of a capture circle, and 3) once the coyote was restrained. In the lab, behavioral actions of captured coyotes were then recorded 4) in the cage at the lab facility and lastly 5) during a manipulated fake arm experiment. Coyotes were given a boldness and aggression rating by observers and an aggression comprehensive score was calculated based on actions in all contexts. Sequencing and restriction length polymorphisms were used to genotype SNPs. We used GLM models to test relationships between genotyped polymorphic SNPs and independent variables of boldness, aggression binary, and aggression comprehensive scores. Some SNPs that were correlated with behavior in the dog were not found to be polymorphic (n=5) or related to behavior in the coyote (5) but new SNPs were also detected in the coyote (9). Nine markers were correlated with boldness and/or aggression measures in serotonin related gene regions. This correlation indicates that certain gene regions may be associated with behavior in coyotes. Such markers may be useful for understanding human-carnivore conflicts in urban settings.
1:30PM All in the Family: Territorial Inheritance and Budding in the Urban Landscape
Hance Ellington; Ashley Wurth; Stan Gehrt
Over the past several decades, coyotes (Canis latrans) have expanded their distribution across most of North America and have adapted to most ecosystems, including urban environments. Urban environments offer both challenges and rewards for coyotes, and these vary across urbanization gradients. Reproductive coyotes maintain territories, where an alpha pair often produces a litter of pups each year. Non-reproductive coyotes employ three non-exclusive strategies for establishing a territory: 1) depart the area and search for a vacant territory (long-distance transiency); 2) stay in the area and wait to occupy a neighboring territory when it becomes vacant; 3) stay within the area and wait to inherit the natal territory. The third strategy could be further divided into two outcomes: a) inherit the full natal territory; or b) create a smaller territory from a portion of the natal territory (budding). Except for long-distance transiency, these strategies can promote kin clustering, whereby closely related individuals live near one another. The success of these strategies and the tolerance of alpha pairs for lingering offspring might be linked to habitat quality. We explored cases of territory inheritance, territory budding, and territory neighbors from 2000-2017 using VHF- and GPS-collars deployed on 261 coyotes. We combined this spatio-temporal dataset with relatedness estimates and pedigree charts to explore patterns of kin clustering across the urbanization gradient. In carnivores, kin clustering is often driven by sex-biased dispersal. We did not find evidence of this, as male and female offspring both inherited territories, budded territories, and formed new adjacent territories. We also found cases of offspring displacing parents from territories. While territorial consolidation did occur, territorial splitting and budding were more common. This suggests that kin clustering plays a role in the establishment of coyote territories in urban environments and could promote higher population densities of coyotes.
1:50PM Interference Competition with Coyotes and Wolves during Variable Prey Availability
Tyler R. Petroelje
The ecological niche can be described as a range of conditions and resource availability in which a species can exist, and two species with strong resource utilization overlap results in competition or exclusion. Interference competition is a low cost and highly effective activity such as stealing food or territory displacement. Coyotes (Canis latrans) and wolves (C. spp.) are sympatric across much of their range in North America where both can be efficient predators of white-tailed deer. We examined three seasons of changing resource availability in relation to white-tailed deer (Odocoileus virginianus) fawns and we assessed the potential for niche overlap of coyotes and wolves using diet, activity, and space-use as evidence for interference competition in Michigan’s Upper Peninsula. We collected and analyzed scat for each species to determine dietary breadth (B) and food niche overlap (α). We used circular analysis to assess activity overlap (Δ) with data from accelerometers onboard global positioning system (GPS) collars worn by coyotes (n = 19) and wolves (n = 12). We used resource utilization functions (RUFs) with canid GPS location data, deer probability, ruffed grouse (Bonasa umbellus) and snowshoe hare (Lepus americanus) densities, and landscape variables to compare space-use at the population-level during changing resource availability when active and inactive. Coyotes and wolves exhibited considerable overlap in diet (B = 3.1-4.9; α = 0.76-1.0), activity (Δ = 0.86-0.92), and space-use of active RUFs across all seasons. Coyotes exploited areas that wolves avoided when inactive, such as areas near roads, or areas with greater prey densities that were not selected for by wolves when active. This improved understanding of how coyotes and wolves coexist with large resource overlaps provides a better understanding of how predator competition can influence predator-prey interactions and how generalists, like coyotes, can exploit narrow differences in resource availability.
2:10PM Spatial Ecology and Landscape-Scale Behavior of Coyotes in South Texas
Justin T. French; John M. Tomeček; Tyler A. Campbell
Despite repeated calls in the literature for further research into basic coyote (Canis latrans) behavior and space use, scientific understanding of these topics remains limited. Our goals were to quantify activity patterns and landscape-scale behaviors of coyotes, as well as correlates of these behaviors that may be of management significance. We captured a total of 16 coyotes between 2 capture events in December 2016 and April 2017 and fitted them with satellite-transmission GPS collars that record locations every 2 hours. We used autocorrelation functions to analyze the structure of coyote activity patterns. We used novel applications of kernel intersection methods to gain insight into the temporal dynamics of coyote space use and inter-individual interactions. We found that coyote movements exhibited strong diel periodicity with subtle differences between social strata. Territorial individuals exhibited strongly crepuscular behavior while transient individuals showed less stable rhythms. With our kernel methods, we were able to uncover behavioral responses to carrion deposition. Four territorial coyotes converged on a calf (Bos taurus) carcass outside of their territories, resulting in subtle changes in individual space use, but a sharp increase in inter-individual overlap. The dynamics of inter-individual interaction were markedly different from this event through the end of the study, 3 months later. This suggests that carrion deposition can have marked and lingering effects on coyote space use.

 

Contributed Paper
Location: Huntington Convention Center of Cleveland Date: October 11, 2018 Time: 12:50 pm - 2:30 pm