FW 403 (001) Fall 2025 Urban Wildlife Management

Overview:

This study seeks to understand more about urban wildlife management in U.S. cities, specifically looking at predator management and rodent control. It looks at rodenticides, as well as non-lethal forms of rodent control. Human-wildlife coexistence and interactions are also discussed in this article.

Methods:

The authors first looked wildlife management and rodent control governmental policy documents, newspaper articles, and fact sheets from wildlife organizations. They then chose fourteen urban wildlife management plans that prioritized nonlethal management of predators and rodent control. They conducted a direct content analysis qualitatively on the wildlife documents. The analysis consisted of each researcher reading the documents and finding relevant themes, exchanging notes with each other, and lastly discussed together the themes/subthemes that felt most relevant to the group about co-existence based urban wildlife management, shown in the table below.

Results:

The researchers found that the urban wildlife plans desired for human-wildlife coexistence. Additionally, they found that the plans were against eradicating species that are considered “nuisance species” and that some cities were okay with living near predators that may pose a risk for humans. Humans should instead get used to living with them, with coyotes being included in this plan as long as it is in the boundaries that they should exist in. The plans also are against killing urban wildlife, unless the animal is seriously aggressive. Normalizing human-wildlife interactions that are unproblematic are also important to show the public that interactions with urban wildlife can be positive.

When looking at rodent control, rodenticides have been most popular to control rat populations. However, predators that consume rats that have poisoned have also perished because of the poison that was in the rats. Thus, there has been more of a movement to ban these rodenticides. Some nonlethal methods to control rat populations are mostly preventative measures that limit the possibility of rat populations to occur in a specific area.

Reflection/Critiques:

I found this study to be very informative when looking at urban wildlife plans from around the United States. I also found it interesting what the urban wildlife management plans had to say about predator management. However, I do think that they could have benefited from incorporating data about different types of human attitudes toward wildlife. Going more in depth about the history of certain species and why humans feel a certain way towards them could be helpful as well. Lastly, I found the data analysis to be lacking a bit and not as professional as I would have thought.

References:

Hunold, C., & Mazuchowski, M. (2020). Human–wildlife coexistence in urban wildlife management: Insights from Nonlethal Predator Management and rodenticide bans. Animals, 10(11), 1983. https://doi.org/10.3390/ani10111983 

Background and Overview

With two-thirds of humanity expected to live in urban areas within the next few decades and cities expanding across the globe, we’re creating entirely new ecosystems. While much attention has been paid to how urbanization affects wildlife abundance and diversity, less is known about how cities influence disease transmission among wildlife populations. This is a critical gap in our knowledge, especially since many wildlife pathogens can also infect humans or threaten already vulnerable animal species.

Cities create dramatic changes in the landscape: more impervious surfaces like roads and buildings, altered microclimates with heat island effects, concentrated human populations, and significantly reduced biodiversity. These changes don’t just affect which animals live in cities—they fundamentally alter how diseases spread among wildlife. Researchers hypothesized that urbanization would influence wildlife–pathogen interactions through several mechanisms: changes in host biodiversity, altered contact rates due to resource provisioning, environmental contamination, and climate modifications.

Methods

Rather than conducting new field experiments, this paper synthesized existing research on wildlife diseases across urban–rural gradients. The authors drew from case studies spanning multiple continents, taxonomic groups, and pathogen types. They examined how urbanization affected three key components of disease transmission: hosts (the animals that carry diseases), pathogens (the disease-causing agents themselves), and vectors (organisms like ticks and mosquitoes that transmit diseases between hosts).

The researchers categorized urbanization effects into several major themes: biodiversity loss and the dilution effect, resource provisioning and host contact rates, pathogen exposure and pollution, and climate-related changes. For each theme, they identified specific host–pathogen systems that illustrated how urban landscapes alter disease dynamics. Examples ranged from Lyme disease in white-footed mice in northeastern United States suburbs to toxoplasmosis in sea otters off the California coast. Urbanization was typically quantified using measures like human population density, impervious surface coverage, and distance from urban centers.

Results

The picture that emerged from this synthesis is complex and sometimes contradictory. Overall, urbanization reduces the abundance of many wildlife parasites simply because it eliminates most wildlife species and their associated pathogens from urban cores. However, for species that do adapt to city life, disease dynamics can intensify in surprising ways.

One of the most interesting findings involves the “dilution effect.” In areas with high biodiversity, disease transmission can actually decrease because vectors like ticks feed on multiple host species that vary in their ability to spread pathogens. In urbanized areas with low host diversity, competent reservoir hosts (like white-footed mice for Lyme disease) can become proportionally more abundant, leading to increased infection rates in both ticks and humans. Similar patterns were found for West Nile virus, where areas with lower bird diversity showed higher infection rates.

Resource provisioning in cities—both intentional, like bird feeders, and accidental, like garbage—creates hotspots where wildlife congregate. This dramatically increases contact rates among animals. Studies of urban raccoons showed that clumped resources led to higher population densities and increased prevalence of raccoon roundworm, particularly among juveniles. Interestingly, the spatial distribution of resources mattered as much as their abundance.

Environmental contamination also played a major role. Urban runoff carrying cat feces led to toxoplasmosis infections in southern sea otters, with infection rates three times higher in areas of maximum freshwater runoff near human population centers. The urban heat island effect extended the activity period of disease-carrying ticks in Stockholm, coinciding with elevated tick-borne encephalitis cases.

Perhaps most concerning for conservation, the researchers found evidence that diseases maintained in abundant urban-adapted species (like gray squirrels or raccoons) can spill over to affect rarer wildlife species. The introduction of gray squirrels carrying a lethal paramyxovirus has contributed significantly to red squirrel declines in the UK, with the effect amplified by food provisioning that increases contact rates between species.

Reflection and Critiques

I find the complexity of these patterns fascinating—urbanization doesn’t simply increase or decrease disease risk; it fundamentally reshapes the entire disease landscape in ways that vary by pathogen, host, and specific urban characteristics. The idea that cities might reduce overall parasite diversity while intensifying transmission among adapted species makes intuitive sense and has important implications for both wildlife conservation and human health.

One strength of this paper is its recognition that multiple mechanisms can work in opposite directions. For example, supplemental feeding increases contact rates (bad for disease spread) but might also improve host nutrition and immunity (good for resisting infection). Similarly, milder urban winters could increase vector survival but might also help infected animals survive that would otherwise die from secondary causes like starvation. I appreciate that the authors don’t oversimplify these relationships.

However, this paper is a review rather than a primary research study, which means it’s limited by the quality and scope of existing research. The authors acknowledge this limitation and call for more experimental and modeling approaches. I would have liked to see more discussion of publication bias—are researchers more likely to publish and report cases where urbanization does affect disease dynamics, potentially skewing our understanding?

I also think the paper could have explored socioeconomic dimensions more deeply. They mention briefly that higher family incomes predict greater plant diversity in Phoenix, but urban ecology involves enormous variation in resource availability, green space access, and environmental quality across different neighborhoods. Disease risks probably vary significantly within cities based on these factors, not just across the urban-rural gradient.

The suggestion that urban planning could be used as a disease management tool is intriguing but feels underdeveloped. How realistic is it to design cities that maintain high biodiversity while supporting dense human populations? What would that actually look like in practice? This seems like an area ripe for future research, especially as cities continue to grow.

Overall, this paper does an excellent job of synthesizing a complex and emerging field. It raises as many questions as it answers, which is exactly what a good review should do. As someone interested in conservation, I’m left wondering how we can better protect vulnerable wildlife species from disease spillover while managing the very real urban-adapted reservoir hosts that sustain these pathogens. The intersection of urban planning, wildlife management, and public health will only become more important as urbanization continues its rapid global expansion.

Bradley, C. A., & Altizer, S. (2007). Urbanization and the ecology of wildlife diseases. Trends in Ecology & Evolution, 22(2), 95-102.

Habitat fragmentation and destruction is one of the primary drivers of extinction and species’ endangerment in today’s ever-evolving world. With impervious surfaces becoming very prevalent as urban areas continue to grow and sprawl, animals are left without safe passageways within urban settings. One solution that has gained traction and support are ecological corridors. Ecological corridors or wildlife corridors are physical green spaces that are protected from surrounding human development that allow for a natural passageway between dangerous environments such as highways, cities, and other development.

One study in France in 2020 wanted to test the efficacy of these corridors through various least-cost paths (LCPs) that both reduce cost of development of a corridor with success-rate of a well-used corridor by wildlife. This study was done primarily using mark-release-recapture (MRR) methods for moths, and using audio playback of calls for passerines to get a broader scope of data for determining future landscape planning decisions for wildlife corridors.

The study area for this research consisted of two medium-sized cities within France (Rennes and Lens). Both sites were comprised of a rough half and half split between “artificialized surfaces” (man-made structures, developments) and urban green spaces (parks, yards, large medians). The study groups of moths and passerines were carefully picked for both their vulnerability to urban development and their previously noted behaviors with movement across urban settings.

After determining the habitat data for each experimental group, the study modeled a few predictions for effective corridors using LCP models in ArcGIS. In these models, they cross-referenced high density habitats with rough resistance values of the animals to travel/move near specific land types. 

The mark-release-recapture for the moth study group was conducted in 2015 in Lens and 2016 in Rennes, with results primarily relying on the amount of individuals recaptured within specific areas across the city. Additionally, each recapture was replicated three times per area for accuracy.

Then the playback recalls for the passerine study group were conducted from April to May in Lens and 2016 in Rennes. These trials were to test response behavior of passerines to specific areas based on development. The variables for this group were testing how far an individual would fly based on the artificial calls and their response time to the call. 

The data was collected into mixed models to contextualize the connectivity in context with the variables tested of moths and birds to the different levels of urban development. The amount of connectivity was categorized into two different sections, highly connecting contexts (HCCs like green spaces and less developed areas) and less connecting contexts (LCCs like buildings, impervious surfaces, and more developed areas). 

For the moth recapture group, among marked individuals, 77% of them were recaptured in HCC areas and and 23% were recaptured in LCC areas.

For the passerine callback group, 66% of birds had a positive response (significant movement speed and distance moved). Overall, in the HCC areas, it was observed that there was significantly higher movement distance (~84m) and speed on average than in LCC areas (~46m). Additionally, there was a longer delay in response from passerines within LCC areas than in HCC areas. 

The larger results show that moths were 4 times more likely to be recaptured in HCC than in LCC areas. However, the study admits that some likely explanations for this could have been due to the presence of light pollution and habitat fragmentation within the cities when compared to natural habitats. This supported the original hypothesis that natural areas do help to facilitate moth movement and dispersal. Similarly, passerines did travel significantly more in HCC than LCC areas. Also, since passerines reacted quicker in HCC areas, it suggests that they do react quicker with territorial behaviors in more natural settings. This shows that urban matrixes could be contributing to an overall slowing down of both movement and responses from local wildlife. 

For future research, the study suggests that shifting to more small mammals studies in a similar habitat connectivity context could be useful for aggregating data and drawing more connections for urban planners. Additionally, this study included many species from both moths and passerines, and still seeing large trends towards more movement and faster responses in natural settings, showing that this effect is not specialized towards specific species. However they also point out that every single city is going to have a slightly different matrix of developed to non-developed areas, hampering the ability for a blanket-approach to be possible. In future studies and urban planning, specialized research and approaches need to be taken in context to the city they are taking place in. Only broader knowledge of impacted behaviors and movements can be applied across multiple areas for baseline understanding to be built upon.

Balbi, M., Croci, S., Petit, E., Butet, A., Georges, R., Madec, L., Caudal, J. & Ernoult, A., (2020, November 24). Least-cost path analysis for urban greenways planning: A test with moths and birds across two habitats and two cities. Journal of Applied Ecology, Volume 58, Issue 3, Pages 632-643, https://doi.org/10.1111/1365-2664.13800 

Background and Overview:

The increase in human population has led to the increase of urban areas, leading many bird species to develop new ways to thrive under these novel conditions. An important fitness technique is how birds respond to fear stimuli. Black-capped chickadees, a common fixture in urban environments due to their non-migratory nature and success in urban parks and woodlands, have developed new behaviors that include altering vocal and nesting behaviors as well as being tolerant of a noisy environment. This makes them a good candidate to study fear response. Anthropogenic impacts like noise, human presence, and novel objects do not appear to have an impact on chickadee fitness. Because of this, researchers hypothesized that fear responses would decrease with the increase in urbanization.

Methods:

24 feeding stations were set up around Kent County, Michigan, which includes suburban and rural areas as well as a mid sized city (Grand Rapids). All 24 stations were at least one kilometer apart and were located in parks owned by the city of Grand Rapids or by the county. Automatic feeders that dispensed seed at peak foraging hours were utilized. As controls, feeders were observed with no additional stimuli and when a familiar object (a branch) was placed at the feeder. The experimental manipulations were: the presence of a cat model, the presence of a novel object, anthropogenic noise, and human approach. Urbanization was quantified by percent of impervious surfaces, distance from the center of Grand Rapids, land cover breakdown, and road length. Each feeder was observed from a hunting blind for seven minutes, then researchers replenished the seed and added either a branch, cat model, or novel object. When testing noise, pink noise was played at steadily increasing increments while observers recorded the number of chickadees present at regular intervals. Human presence was tested by a researching standing increasingly closer to the feeder and recording the number of visits.

Results
Overall, chickadee visits to feeders increased as urbanization increased across the sample sites. Parks that failed to attract chickadees were at the top end of the urbanization gradient. It was found that the branch had no effect on the number of chickadee visits to a feeder, indicating that the presence of an object alone is not enough to deter birds. With nearly all stimuli, chickadee visits to feeders increased with urbanization, except for the introduction of a model cat. When the cat was introduced, chickadee visits did not change with urbanization; rather, they remained about the same across the gradient. Urbanization also led to a decreased fear of noise stimulation. Cats and increased noise are both common effects of urbanization, yet they have opposite impacts on chickadee fear behaviors.

Reflection and Critiques

It seems to me that chickadees are beginning to exhibit less fear response to human-caused effects of urbanization, like noise and the presence of people. I think this is likely because people generally aren’t a threat to chickadees- unlike cats, which are very much a danger. It makes sense to me that heightened fear response towards an increased feline presence would happen in urban areas. I would like to know how realistic the fake cat was, because I’m not sure how much a toy cat really looks like a real cat to birds. This doesn’t seem to have an impact on the study, however. I honestly don’t have a lot to critique; this study was well-planned, very thought out, and did a good job minimizing the impact of any outside variables. My one gripe is that I found the way they graphed the results to be somewhat difficult to follow; it was a very statistical analysis-heavy approach, and I am not exactly a shining example of a statistician. They also only graphed results for two of the experimental variables (cat presence and noise) and I would have liked to see more visualizations of the results. Overall, though, I found this to be an interesting and well-done study.

Van Donselaar, J.L., Atma, J.L., Kruyf, Z.A. et al. Urbanization alters fear behavior in black-capped chickadees. Urban Ecosyst 21, 1043–1051 (2018). https://doi.org/10.1007/s11252-018-0783-5

Overview

Human-Wildlife interactions are becoming increasingly common in urban areas. People are particularly concerned about interactions with carnivores, such as urban foxes (Vulpes vulpes). Urban foxes are often described as “bold” or “fearless,” but this study challenges that idea by breaking down what “boldness” actually means. In this study, the authors focus on two key behaviors: neophobia, which is the fear of new things, and wariness, which is the fear of potential threats. The authors then explored how these traits vary depending on a fox’s social status. They wanted to know whether dominance within a group, rather than city living itself, shapes how foxes behave around unfamiliar or risky situations.

Methods

The study was conducted in northwest Bristol, England, an area with a well-documented history of urban fox research. Six fox social groups were observed across residential neighborhoods, each with its own territory. Within each territory, researchers worked with homeowners who already fed foxes, setting up small experimental arenas in their backyards. This approach increased visitation rates and allowed for consistent observations without drastically altering the foxes’ normal behavior.

Two main experiments were designed to measure different responses. The first was a novelty test, which measureed neophobia. During this test, a shiny reflective garden ornament was placed near a food source to represent an unfamiliar object. The second tested wariness, introducing a line soaked in wolf urine, a scent cue meant to simulate a natural predator. These experiments were conducted during two 20-day periods: one in late November and early December, and another in May, to test for possible seasonal effects. Food was placed in the arena each evening to attract foxes, and all activity was recorded using motion-sensitive cameras positioned to capture multiple angles.

Researchers identified individual foxes by their distinct markings, scars, and tail shapes, and ranked them as either dominant or subordinate based on observed interactions. Dominant foxes typically controlled territory use and access to food, while subordinates tended to be younger, lower-ranking individuals. The team recorded each fox’s hesitation time, level of alertness, time spent feeding, and frequency of entries into the test area. They then analyzed these behaviors using principal components analysis (PCA) and linear mixed models to look for patterns between social status, season, and social context (foraging alone or with others).

Results

The study found that dominant foxes were more cautious, showing higher levels of both neophobia and wariness. They approached new or threatening objects more slowly and displayed longer periods of vigilance. Subordinate foxes were more exploratory and willing to take risks, likely due to their lower access to food and greater need to forage widely. When foxes were observed with others, both dominants and subordinates were less fearful, suggesting that social presence reduces perceived risk. Season had no significant effect, meaning social structure was the strongest factor shaping behavior.

Discussion

These results suggest that the “bold” foxes people often see near homes or gardens are usually subordinates taking greater risks to survive, not animals evolving to be braver, which is important for wildlife management. Actions like culling, which remove dominant individuals, can break up social groups and lead to an increase in subordinate foxes.

Critical Analysis

I thought the authors of this paper did a good job linking fox behavior to social structure and challenging the idea that urban foxes are simply “getting bolder.” However, I feel like the novelty test could have been more controlled as the ornament used moved in the wind and reflected light, which likely triggered several reactions at once, making it hard to tell what actually caused the foxes’ hesitation. Another limitation is that all testing occurred in feeding backyards, where foxes were already comfortable around people. Including non-feeding sites would make results more representative of typical urban fox behavior.

Reference

Padovani, R., Shi, Z., & Harris, S. (2021). Are British urban foxes (Vulpes vulpes) “bold”? The importance of understanding human–wildlife interactions in urban areas. Ecology and Evolution, 11(2), 835–851. https://doi.org/10.1002/ece3.7087

Intro: This study was conducted to explore the barriers to collaboration in the context of a deer crisis in the Scottish Highlands, where deer numbers in 2008 were higher than at any time in recorded history. The researchers explored the role of recreational hunters in government mandated lethal control. Using both qualitative and quantitative analyses, they determined that hunting traditions, and personal preferences, reinforced by antipathy toward conservations and land stewards were the major barriers to hunters shooting more deer each season.

Methods: MacMillan and Leitch as discussed earlier, used both qualitative and quantitative methods to determine attitudes towards this emotionally heated issue. They started with a mail survey to individual sporting estate owners, and followed that with a series of interviews with selected owners. They selected 172 estates out of 300 options.

Results: MacMillan & Leitch found that estate owners had nuanced perceptions of their role in the ecosystem, and the role of their land on conservation management. They found that most of their surveyed individuals owned the estates for personal as opposed to business reasons, and that they saw themselves as caretakers of the land. They perceived high deer populations as an indicator of healthy ecosystems, and were mainly focused on maximizing trophy stag quality for sport and prestige. (This is foundational literature for what would come to be known as QDM, or quality deer management.) Overall, they found that estate management was shaped by culture, lifestyle, and social identity even more so than ecology or economics, and that conflict persists between private estate culture and public conservation agendas.

Management implications: In order to meet conservation goals, management agencies must increase hunting substantially, and consistently. Estate landowners prefer “soft” incentives like grants and marketing as opposed to taxes and regulation. Owners were also enthusiastic about venison marketing as a way to increase hunting but this is unlikely to succeed in the researchers opinion due to a various economic reasons. Additionally, British sport hunting culture historically has disdain for “hunting for the pot”, meat focused hunting is seen as unsporting or greedy. In order to combat these things, conservationists and agency workers must engage more positively with landowners, and human dimensions will play a large role in the success or failure of those efforts.

Overview:
Chronic wasting disease has become an increasing concern for white-tailed deer in the U.S. Along with this, urban deer densities have risen as more areas are urbanized and deer populations grow. This leads to an aggregation of deer, as they have smaller spaces to occupy around human residential communities and gardens. CWD is transmitted at highest frequencies when there is high traffic of deer over one area. Storm Et. Al. researched the connection between deer density, landscape features, and soil clay content with chronic wasting disease transmission. The study was conducted on young white-tailed deer, less than 2 years old, in Wisconsin.

Methods:
They conducted this study in areas nearby reported CWD outbreaks. They collected samples from lymph nodes of harvested deer by hunters. Registration, including the location of deer harvested, was mandatory. Most deer were harvested in fall, giving them 1.5 years of potential exposure time. Helicopter counts were used to estimate deer density in research areas. Data from the National Land Cover Database and data from NRCS Survey Spatial and Tabular Data around the CWD core areas were used for landscape and clay soil content connections.

Results:
Their findings actually showed that traditional density models did not have a linear correlation with CWD cases. They did find a positive relationship between deciduous forest landcover and CWD cases.

Discussion:
They stated that the social dynamics of yearling deer are likely too complex for density relationships to predict CWD transmission. Social dynamics are matriarchical at young ages, and circles change throughout a deer’s life, meaning deer are interacting in large webs. However, deciduous forest cover was a reliable predictor, likely due to high use of these spaces by deer.

Critical Analysis:
They looked at a lot of factors that could contribute to CWD transmission, but did not focus in on one. I feel like there were a lot of lurking variables in this study, and there could be some answers missed. Mostly, I think it’s worth looking specifically at deer density by comparing a wildland area with an urban/suburban area. That might produce clearer results on the relationship between deer density and disease prevalence. However, I recognize that the limitation here is the culling of deer for sampling in urban/suburban spaces.