Humanization of wildlife gut microbiota in urban environments

Urbanization is rapidly altering Earth’s environments, demanding investigations of the impacts on resident wildlife. Here, we show that urban populations of coyotes (Canis latrans) and crested anole lizards (Anolis cristatellus) acquire gut microbiota constituents found in humans, including the gut bacterial lineages most significantly associated with urbanization in humans (e.g., Bacteroides). Comparisons of urban and rural wildlife and human populations revealed significant convergence of the gut microbiota among urban host populations. Remarkably, all microbial lineages found in humans that were overrepresented in urban wildlife relative to rural wildlife were also overrepresented in urban humans relative to rural humans. These results indicate parallel effects of urbanization on human and wildlife gut microbiota and suggest spillover of bacteria from humans into wildlife in cities.

Diet reveals potential for competition and coexistence among coyotes (Canis latrans), red foxes (Vulpes vulpes), and gray foxes (Urocyon cinereoargenteus)

Species can alleviate competition by reducing diet overlap. Nonnative coyotes (Canis latrans (Say, 1823)) and historically native gray foxes (Urocyon cinereoargenteus (Schreber, 1775)) have expanded their ranges and may compete with native red foxes (Vulpes vulpes (Linnaeus, 1758)). To examine potential competition among canids in Maine, we compared δ13C and δ15N from muscle and hair samples to assess relative resource use, and we compared frequency of occurrence of prey items from stomach contents to assess diets. For these species, red foxes consumed anthropogenically-based foods the most in fall-early winter, gray foxes consumed anthropogenically-based foods the most in summer, and coyotes consumed anthropogenically-based foods the least in all seasons. Coyotes held the highest relative trophic position in fall-early winter, red foxes held the highest relative trophic position in summer, and gray foxes held the lowest relative trophic position. Based on stomach contents, gray foxes had the broadest diet and consumed the most plants, and coyotes had the narrowest diet. Red foxes were the only species to show isotopic niche overlap with both potential competitors across seasons. Thus they may be most susceptible to competitive exclusion among these canids, with implications for community dynamics as ranges shift due to human activity.

Coyote (Canis latrans) predation of colonial rodents facilitated by Golden Eagles (Aquila chrysaetos)

Interactions between Coyote (Canis latrans) and Golden Eagle (Aquila chrysaetos) are complex and likely not yet fully documented or understood. I observed a Coyote prey on a Black-tailed Prairie Dog (Cynomys ludovicianus) at the edge of a large colony in Grasslands National Park, Saskatchewan. The prairie dogs were vigilant toward three Golden Eagles circling above, and the Coyote apparently used this to its advantage. As such, the eagles appeared to facilitate the ability of the Coyote to rush in virtually undetected and prey on a prairie dog that was distracted by the avian predators. This observation is of scientific interest because it is another example of the varied interactions between Coyotes and Golden Eagles, which is competitive and includes kleptoparasitism.

Interface of Human/Wildlife Interactions: An Example of a Bold Coyote (Canis latrans) in Atlanta, GA, USA

There is arguably no other North American species that better illustrates the complexities of the human-wildlife interface than the coyote. In this study, a melanistic coyote in metropolitan Atlanta, Georgia was exhibiting unusually bold behaviors that included encounters with humans, domestic dogs, and attempts to enter homes. After tracking this coyote (nicknamed Carmine) across a highly urbanized landscape with participatory science, including at least 80 publicly reported sightings, he was captured and relocated to a wildlife sanctuary. Genome-wide analyses revealed 92.8% coyote ancestry, 1.7% gray wolf ancestry, and 5.5% domestic dog ancestry. The dog alleles in Carmine’s genome were estimated to have been acquired by his ancestors 14–29 years ago. Despite his bold behavior, Carmine did not carry any mutations known to shape hypersociability in canines. He did, however, carry a single copy of the dominant mutation responsible for his melanistic coat color. This detailed study of Carmine dispels common assumptions about the reticent coyote personality and the origins of behavior. His unusual bold behavior created a higher level of human-coyote interaction. He now serves as a public ambassador for human-wildlife coexistence, urging the global community to reconsider mythologies about wildlife and promote coexistence with them in landscapes significantly altered by human activity in our rapidly changing world.