Coyotes are becoming an increasingly important signal of how urban growth, fragmented habitats and a warming climate are reshaping wildlife disease. A new multi-city study across North America finds that sarcoptic mange, a debilitating skin disease caused by the mite Sarcoptes scabiei, is more common in urban environments with particular combinations of human density, habitat connectivity and climate conditions. The researchers report that disease occurrence is already linked to the structure of cities and their surrounding landscapes, and they forecast that mange could become more widespread by 2050 as urban areas expand and winters grow milder.
The study focused on coyotes (Canis latrans), one of North America’s most adaptable urban mammals. Coyotes now inhabit landscapes ranging from heavily developed city centers to suburban neighborhoods, industrial zones and remnant natural areas. Their ability to move through human-dominated environments makes them valuable indicators of ecological change, but it also brings them into contact with other wildlife, domestic animals and people. To assess disease patterns without capturing or disturbing the animals, the research team analyzed images collected through camera-trap biomonitoring programs operating in multiple North American cities. In these photographs, visible signs of mange—including hair loss, thickened skin and characteristic lesions—were used to estimate disease occurrence.
Sarcoptic mange is transmitted when mites move between hosts through direct contact or contaminated resting sites. The microscopic parasites burrow into the skin, triggering intense irritation and an immune response. Infected animals often scratch excessively, lose fur and develop crusted, inflamed skin. Severe infections can compromise an animal’s ability to regulate body temperature, find food or avoid predators. Although mange is not generally considered a major human health threat, the disease can affect domestic dogs and has significant consequences for wildlife welfare. In coyotes, outbreaks may also alter movement, survival and interactions with other species, potentially influencing urban ecosystems in ways that are difficult to detect from disease records alone.
At the local scale, the researchers found that mange occurred more often at sites with greater urban intensity. Urban intensity captures the degree to which an area is dominated by buildings, roads, paved surfaces and other forms of development. Such landscapes can concentrate animals around predictable food sources, shelter and movement routes, increasing opportunities for contact. Coyotes in cities may gather near waste containers, parks, transport corridors and residential areas, creating repeated encounters among individuals that would otherwise occupy larger, more separated territories. These conditions could increase the probability that mites pass from one host to another, particularly when infected animals continue using shared dens, resting areas or travel paths.
The local findings also revealed a more complex relationship between disease and habitat connectivity. Mange occurrence was higher at sites located near connectivity corridors, places that allow animals to move between otherwise isolated patches of habitat. At first glance, this result may seem to conflict with the idea that fragmentation promotes disease by forcing animals into smaller spaces. However, corridors can function as biological meeting points. They may funnel multiple coyotes through the same narrow routes, increasing contact rates and allowing pathogens to spread across connected populations. Corridors can therefore have contrasting effects: they may improve access to food, shelter and escape routes, while also accelerating the movement of infectious agents through a landscape.
The pattern changed when the scientists compared cities at the continental scale. Cities with higher human population density showed greater mange occurrence, while cities with fewer connectivity corridors also tended to have more disease. This distinction between local and continental patterns is crucial. A corridor may increase transmission at a particular site by concentrating animal movement, yet a city with an overall shortage of corridors may impose broader habitat constraints that increase crowding, reduce escape options or intensify contact around the remaining usable spaces. The findings suggest that disease risk cannot be predicted from a single landscape feature. Instead, it emerges from the interaction of urban form, animal behavior and the spatial arrangement of habitat across several scales.
Climate change adds another layer to this interaction. Winter conditions are especially important for both coyotes and mange mites. Cold temperatures can limit host activity and reduce the survival of mites away from an animal’s body, while harsh weather may constrain movement and alter where coyotes seek shelter. As winters become milder, infected and susceptible animals may remain active for longer periods, increasing opportunities for contact. Warmer conditions could also improve the survival of mites in the environment, although the precise effect will depend on humidity, temperature fluctuations and the type of surface where mites are deposited. The researchers incorporated these ecological relationships into projections of future disease occurrence under expected urban growth and climate change.
Their forecasts indicate that mange is likely to increase across cities by 2050, with the strongest changes expected at northern latitudes. Northern cities may experience a particularly pronounced shift because they are projected to undergo both urban densification and substantial winter warming. Densification can compress wildlife movement into fewer remaining green spaces and corridors, while milder winters may extend the period during which coyotes and mites remain active. Together, these forces could increase overlap between hosts and improve the persistence of the parasite. The study does not suggest that every northern city will experience the same outcome, but it identifies northern urban regions as potential hotspots for future change.
The results carry practical implications for city planners, wildlife managers and public-health agencies. Habitat connectivity is often promoted because it supports movement, genetic exchange and access to resources, and the study does not argue against connected landscapes. Instead, it highlights the need to design corridors with disease ecology in mind. Wider or more numerous routes could reduce bottlenecks, while strategically distributed green spaces might prevent animals from being forced into a small number of high-contact locations. Monitoring corridors with camera traps could help identify emerging hotspots before severe disease becomes widespread. Managers might also combine surveillance with public education, responsible waste management and guidance for reducing contact between pets and visibly infected wildlife.
The researchers emphasize that proactive management will become increasingly important as cities expand. Camera traps offer a relatively low-impact way to monitor disease over large areas and can reveal changes in both animal distribution and visible health. Repeated imaging can help distinguish a temporary increase from a persistent trend, while linking photographs with temperature, land-cover and movement data can clarify the mechanisms behind transmission. Future work will need to determine how often infected coyotes recover, how mange affects survival and reproduction, and how frequently mites move between coyotes, foxes, domestic dogs and other hosts. Even with those uncertainties, the study provides a warning that urban wildlife disease is not driven by development or climate alone. It is produced by the changing overlap among animals, infrastructure, habitat and weather—a relationship that cities may still be able to reshape before projected increases become reality.
Subject of Research: Sarcoptic mange occurrence in urban coyotes and its relationship with urban density, habitat connectivity and climate change.
Article Title: Wildlife disease occurrence increases with changes to urban density, habitat connectivity and climate.
Article References: Gelmi-Candusso, T.A., Murray, M.H., Rodriguez, P. et al. Wildlife disease occurrence increases with changes to urban density, habitat connectivity and climate. Nature Cities (2026). https://doi.org/10.1038/s44284-026-00501-4
Image Credits: AI Generated
DOI: https://doi.org/10.1038/s44284-026-00501-4
Keywords: wildlife disease, sarcoptic mange, coyotes, urban ecology, habitat connectivity, climate change, camera traps, zoonoses, urban planning, Sarcoptes scabiei
Tags: camera-trap biomonitoring for wildlife healthclimate change and disease forecasting in urban areascoyotes as indicators of ecological changeeffects of climate change on wildlife diseaseshabitat connectivity and disease spreadimpact of urbanization on wildlife healthinfluence of human density on disease prevalencesarcoptic mange in coyotesurban ecology and disease dynamicsurban habitat fragmentation and pathogen transmissionurban wildlife diseasewildlife disease risk in North American cities
