FW 403 (001) Fall 2025 Urban Wildlife Management

Overview

The article I chose to review is “Black-tailed deer resource selection reveals some mechanisms behind the ‘luxury effect’ in urban wildlife” by Fisher et al. (2024). The study focuses on how urban deer choose where they live and feed, particularly in relation to wealthier neighborhoods. The “luxury effect” is the idea that richer areas often have more biodiversity, and this study aimed to see how that effect applies to black-tailed deer in Oak Bay, British Columbia. The authors explored whether features like big yards, green lawns, parks, and golf courses were influencing where deer spend their time.

The main goal of this study was to better understand how urban environments are providing food and shelter for deer and how that affects their movements and populations. This is important because as cities grow, interactions between people and deer are becoming more common, sometimes leading to conflicts. By figuring out what attracts deer, city planners and wildlife managers can make better decisions to balance human needs with healthy wildlife populations.

Methods

This research was conducted in Oak Bay, a wealthy neighborhood on Vancouver Island. The study area included residential neighborhoods, parks, golf courses, and the surrounding urban matrix.

Between 2018 and 2019, researchers captured 20 female black-tailed deer and fitted them with GPS collars. These collars collected location data every 13 hours, which allowed the researchers to map where the deer went throughout the year.

They then analyzed which features were most common in the locations the deer chose compared to random points across the landscape. The features they focused on were:

• Lot size (small, medium, or large yards)
• Vegetation greenness (NDVI, which measures how productive and healthy plants are)
• Tree cover
• Proximity to parks and golf courses
• Road density

They also calculated each deer’s home range size using kernel density estimation, which gave a sense of how much space each deer used over time.

Results

The results showed strong evidence for the luxury effect. Large residential lots were the most important factor as deer were over twice as likely to be found in areas with bigger yards. These large lots also tended to have more irrigated gardens and lawns, which gave deer a steady food source.

Deer also preferred areas with greener vegetation, as well as locations near parks and golf courses. These spaces offered both food and cover. Roads, on the other hand, were avoided, which suggests that traffic is still a major deterrent.

Tree cover wasn’t a big factor in whether deer used an area. Because food and water were so easy to find in Oak Bay, the deer had very small home ranges, about a quarter of the size of deer living in wild areas, meaning that the same deer were staying in the same neighborhoods for long periods of time, which could explain why residents report seeing deer frequently.

Critique and Reflection of this Article

I found this article very interesting because it shows that urban design, particularly in wealthier areas, can actually create perfect deer habitat. The authors did a great job using GPS tracking and statistical models to clearly show how lot size and vegetation greenness are influencing deer behavior.

One limitation of the study is that it only focused on female deer, so we don’t know if males are using the landscape in the same way. It also didn’t look at how deer behavior might change across seasons, which could be important for things like fawning or mating.

References

Fisher, J. T., Fuller, H. W., Hering, A., Frey, S., & Fisher, A. C. (2024). Black-tailed deer resource selection reveals some mechanisms behind the ‘luxury effect’ in urban wildlife. Urban Ecosystems, 27, 63–74. https://doi.org/10.1007/s11252-023-01428-7

Schulte-Hostedde AI, Mazal Z, Jardine CM, Gagnon J. Enhanced access to anthropogenic food waste is related to hyperglycemia in raccoons (Procyon lotor). Conserv Physiol. 2018 Jun 13;6(1):coy026. doi: 10.1093/conphys/coy026. PMID: 29992022; PMCID: PMC6025200. https://pmc.ncbi.nlm.nih.gov/articles/PMC6025200/#coy026C24

The study makes a hypothesis that if glucose metabolism, adiposity, and body weight are affected by consumption of anthropogenic food waste, then they predict that raccoons with greater access will have higher body mass and evidence of hyperglyclemia than those with reduced access. Samples were collected from 3 different location types in Southern Ontario. Each location type had varying access to anthropogenic food: one being the Toronto Zoo grounds, with access to garbage bins, on site restaurants, etc. Moderate access sites included 3 conservation areas in Grand River Watershed, Ontario in 2012. People do not live in these areas but in close proximity residential areas. Food was only available during weekly municipal garbage collection. Low access food waste site was a farming area in Grand River Watershed, Ontario in 2012.

They limited analysis of the raccoon samples to 60 adult raccoons sampled during the months of July and August to account for seasonal variations in body weight. Their estimates of consumption were qualitative and based on potential access to food, not specific bodily measurements. More precise estimates of consumption, for example, use of stable isotopes for corn, would help determine the relative consumption of processed foods.

With the sampling of raccoons, I believe they could’ve gone further by maybe doing a longer study about from the beginning of their life or different age brackets to see if it affects different groups. It would expand the scope to examine raccoons in different seasons, not just July-August, which restricts variation in body mass. Their distribution of females to males was also highly varied in each access level. For example, there were 5 males selected for the low access area and 16 for the high access area. Because there was a higher amount sampled in the high access area, there is more variability that can be accounted for and more reliable statistical analysis. There is a slight variation in weight between females and males, which was significant in the study. There was no interaction between sex and the effect of access to anthropogenic food waste on body weight. In the future, there should be more even sample sizes to accurately measure this.

No significant difference was observed between the mean body weights of the raccoons with moderate and low access to anthropogenic food waste. In this study, they assumed that variation in body mass would be the result of differences in fat mass, but there could be differences in body size or composition instead. Their are many different ways to look at body weight distribution. Raccoons with high access to anthropogenic food waste had significantly higher glycemia levels than those with moderate and low access to anthropogenic food waste. Leptin was not significantly different among sites nor was the body mass and leptin. With other wildlife groups, such as black bear and white tail deer, leptin has had both significant and insignificant results of correlation with adiposity (fat deposition). More studies are needed to understand the impact of lepin in different wildlife groups.

Overall, there is not enough research on human activities and wildlife nutrition beyond ecological and life history consequences. There needs to be more focus on how these diets affect the endocrine and metabolic functions of these species. This may have implications for human’s food sources containing more pesticides, as well as disposal methods as waste is only increasing. It makes me wonder what solutions to wildlife access to anthropogenic food would be, especially in high access areas. Hyperglycemia and adiposity could potentially compomise the immune system of animals and increase chances of disease transmission. This could threaten the livelihood of such species. It would be interesting to look at how species are adapting to anthropogenic food sources, and what metabolic pathways are formed with unique nutrients now in their diet.

Urban areas commonly develop in formerly biodiverse habitats, such as wetlands and valleys. This development tends to lead to an overall decrease in biodiversity, but some raptors have adapted their predation strategies to thrive in urban ecosystems. However, urban environments can also pose a higher threat to raptors through anthropogenic causes, such as window strikes and exposure to chemicals. This is especially true of anticoagulant rodenticides (ARs), which are primarily used on rodents in urban settings. The aim of this study was to determine the if exposure to ARs in barred owls stemmed from consumption of rodents with ARs in their system, or if secondary exposure from predating at bait stations caused the exposure. 

Owl pellets and prey remains were collected at nesting and roosting sites in and around Vancouver, British Columbia, Canada. The sites were found by local chapters of naturalist clubs, and playbacks were used at said sites to determine presence of barred owls. Bait stations of ARs were also scouted and their locations and distances from nests were marked. After collection, the pellets were dissected, and prey items were identified. 

The researchers found that the primary prey product of their studied owls was young adult rats. Barred owls with higher urban development surrounding their nests and roosts also had an relatively larger proportion of rats in their diets. Because rats are one of the primary targets of ARs, barred owls are subsequently at risk for posioning from secondary exposure to ARs. 

This study does state that barred owl in urban areas in British Columbia are at risk for secondary AR exposure, it never discusses if there is a risk for primary exposure. Primary exposure is mentioned in the abstract and background information, but not in the results, so readers do not know if this is also a reason for concentrations of ARs in barred owls. Furthermore, the researchers do not discuss how these results could apply to other urban areas. Doing so might be considered speculation, but I would like to know more about how we can use their results more broadly. I also would’ve liked to know more about black bait stations used to deploy ARs, so I could know specifically how they are affecting barred owl predation efforts. 

Hindmarch, S. and Elliot, J.E. When Owls Go To Town: The Diet of Urban Barred Owls. Journal of Raptor Research 49 (1): 66-74. https://doi.org/10.3356/jrr-14-00012.1

Overview: This study assessed the public’s perceptions of urban wildlife in Krakow, Poland and compared it with 2010 data. In a questionnaire, the researchers found that wildlife interactions with wild boars, red squirrels, brown hares, red foxes, and roe deer have increased since 2010. Since urbanization is only increasing, it makes sense that human-wildlife interactions are increasing as well.

Methods: The study area was in Krakow, Poland which is the second largest city in Poland. The Vistula River goes through the city which acts as a natural migration corridor for wildlife. The area consists of green patches, agricultural areas, watercourses, and urban land. The researchers sampled the population of Krakow, with 887 responses observed. The questionnaire consisted of sections that observed the population’s attitudes toward wildlife in the city, attitudes toward managing conflict situations with wildlife, socio-demographic information, encounters with wildlife and their reported behavior, and perceptions of conflictual wildlife and their associated problems. This questionnaire conducted in 2020 was similar to the 2010 questionnaire and statistical differences of the sociodemographic variables between the two years were calculated in ANOVA. Chi-square tests were also conducted to evaluate the differences in wildlife in Krakow and the respondents’ attitudes toward wildlife.

Results: The results showed that the socio-demographic factors between 2010 and 2020 were not significantly different. Results also showed that human-wildlife encounters have increased over the decade, with multiple species being significant.

Wildlife	2010 (n)	2020 (n)	Mean (±SD)	χ2	p-Value
Red squirrel (Sciurus vulgaris)	93	791	442 (±493.56)	551.13	<0.001
Hedgehog (Erinaceus roumanicus)	601	701	651 (±70.71)	7.68	0.005
Red fox (Vulpes vulpes)	276	444	360 (±118.79)	39.20	<0.001
Roe deer (Capreolus capreolus)	271	409	340 (±97.58)	28.00	<0.001
Wild boar (Sus scrofa)	130	308	219 (±125.87)	72.34	<0.001
Stone marten (Martes foina)	256	394	325 (±97.58)	29.30	<0.001
Mute swan (Cygnus olor)	490	651	570.5 (±113.84)	22.72	<0.001
Bat (Chiroptera)	257	286	271.5 (±20.51)	1.54	0.213
Mallard (Anas platyrhynchos)	29	703	366 (±476.59)	620.60	<0.001
Brown hare (Lepus europaeus)	66	344	205 (±196.58)	188.50	<0.001

“χ²: p < 0.05; Bonferroni correction: p < 0.025. Italic: significant in Chi Square test, bold: significant after Bonferroni correction, bold and italic: significant in Chi Square test and Bonferroni.”

Additionally, the behavior of the species also changed from 2010 to 2020. More recently, the respondents found wildlife showing more behaviors (Figure B) other than running away from humans when being encountered like in 2010 (Figure A).

“Fig. 1. Canonical correlational analysis (CCA) ordination biplot of wildlife (in red) and their reaction while observing residents (blue arrows) as recorded in Krakow in 2010 (A) and 2020 (B). CCA plots to determine the relationship between wildlife and their observed behaviour.”

The researchers also found that the participants agreed that the most conflict causing species included the roe deer, stone marten, red fox, and wild boar. (Figure A = 2010, Figure B = 2020) The number and types of nuisance wildlife proved to be significantly different.

Lastly, the attitudes of the public were mostly neutral (36%), with around 25% of people being negative and 23% being positive. They found that there was a significant difference in the attitudes of the public between 2010 and 2020.

Critiques: Although this paper was pretty straight forward, I do wish that they mentioned the 2010 data of the public’s overall attitudes like they did with the 2020 data. Additionally, they mentioned in the limitations section that their selection of the participants was not completely random, and that there was only 23% of men representation. I do think picking a better selection of the participants would have been better for a more accurate representation of the Krakow population. Other than that, I did find it interesting to see how human-wildlife encounters have changed from 2010. I think this paper could help wildlife managers understand the public opinion in Krakow in order to inform possible management strategies.

References: Basak, S. M., Hossain, Md. S., O’Mahony, D. T., Okarma, H., Widera, E., & Wierzbowska, I. A. (n.d.). Public perceptions and attitudes toward urban wildlife encounters – a decade of change. ADS. https://ui.adsabs.harvard.edu/abs/2022ScTEn.83455603B/abstract 

This study was conducted to examine the effects of the COVID-19 pandemic on conservation issues among adults with different political affiliations, as well as to determine the relative importance of these issues across the political spectrum. Additionally, it looked to understand how these issues coalesced during the 2020 US general election. It is crucial to determine the changes in the polarization on this broad category of issues because out of 14 major policy issues listed to voters in the study, conservation issues such as endangered species conservation and control of zoonotic disease ranked very low; Even lower than climate change.

The researchers used Qualtrics surveys and distributed them to 1,560 residents in August 2020. The study had quotas for how many respondents they used by state, age, and political affiliation. These political affiliations were assigned the following strata: Conservative Republican, Liberal/Moderate Republican, Independent/Other, Moderate/Conservative Democrat, and Liberal Democrat. Respondents were asked a series of 14 policy questions, with 12 being “standard” policies such as immigration and abortion, and 2 environmental questions. Their answers were on a 5-point scale, with answers ranging from “Not important at all” to “Very important to my vote”.

Researchers found that polarization was highest among the farthest fringes of political ideologies, with the most drastic differences between those who considered themselves furthest right and furthest left. The study found that Democrats experienced positive changes in their opinions (the pandemic made them more favorable to conservation), while Republicans had an adverse change in their views (the pandemic made them less favorable to conservation).

To improve this study, I would have liked to see the changes over a temporal scale represented. For example, the study could have sent Qualtrics surveys to respondents once in 2019 and compared the changes in the resurvey conducted in August 2020. This would have allowed researchers to directly compare individual changes as well as changes in self-reported political affiliations over the course of time. Overall, however, the results showed substantial management implications for state agency workers creating policy as well as lawmakers looking to represent their constituents better.

Casola WR, Beall JM, Nils Peterson M, Larson LR, Brent Jackson S, Stevenson KT. Political polarization of conservation issues in the era of COVID-19: An examination of partisan perspectives and priorities in the United States. J Nat Conserv. 2022 Jun;67:126176. doi: 10.1016/j.jnc.2022.126176. Epub 2022 Mar 26. PMID: 35370533; PMCID: PMC8957370.

https://pmc.ncbi.nlm.nih.gov/articles/PMC8957370/#ab010

Background and purpose: As Canada goose populations have recovered from near extirpation to approximately 113,000 individuals in Indiana over the past 60 years, urban densities have created persistent human-wildlife conflicts and novel behavioral adaptations. Canada geese typically nest on the ground or slightly elevated natural sites like muskrat lodges near water bodies. However, the effects of urbanization on nesting site selection in this species have been understudied. This article documented observations of Canada geese nesting on rooftops 2.6–12.2 meters above ground level in central Indiana to understand how urban environments are influencing nesting behavior in this adaptable waterfowl species.

Methods: Researchers conducted routine nest surveys across three study areas in the Indianapolis Metropolitan Area from March to July 2021. Five rooftop nests were discovered and monitored on a weekly basis. Data collection included capturing band information from adult geese, counting eggs, recording nest materials, and tracking nest success through observations of egg membranes and goslings. Nest characteristics such as height above ground, distance to nearest water body, clutch size, and construction materials were documented. Hatching success was compared between elevated nests and ground-level nests in the same study areas.

Results: Rooftop-nesting Canada geese showed distinct differences from traditional ground nesters. Elevated nests had significantly smaller clutch sizes (average 4.00 eggs) compared to ground nests (5.01 eggs), but achieved 100% hatching success versus only 59.9% for ground-level nests. This suggests that while elevated nesting may reduce reproductive output, it significantly improves nest survival. Nest construction materials differed substantially, with rooftop nests using atypical materials like automotive belts, plastic sheets, and loose gravel with minimal traditional down and body feathers. All five rooftop nests successfully hatched, though goslings from two nests required human rescue due to barriers preventing natural departure. The researchers hypothesize that geese are selecting these elevated sites to avoid ground predators including mammals and human disturbance.

Criticisms: This study provides valuable documentation of an emerging urban adaptation, but several limitations affect the strength of conclusions. The sample size of only five nests is quite small for making broad generalizations about population-level behavioral changes. The study lacks systematic methodology for nest discovery, so it’s unclear whether these represent rare occurrences or a more common behavior that’s simply underreported. I would be interested to know if the researchers were actively searching for rooftop nests or if they just happened upon them during other surveys. Additionally, the research provides no data on long-term gosling survival rates after hatching, which is crucial for determining whether this apparent nesting advantage translates to reproductive success. While hatching success was high, the fact that goslings from two nests required rescue suggests potential survival challenges that could offset the benefits. 

The study also lacks environmental controls such as temperature measurements comparing rooftop versus ground conditions, which could help explain the higher hatching success. I am curious whether this behavior is spreading to other regions or if it represents a local adaptation specific to central Indiana’s urban landscape. Future research would benefit from larger sample sizes across multiple urban areas and longitudinal tracking of gosling survival rates to determine the true fitness consequences of this behavior.

Reference:

Shearer, D. J., Carter, T. C., & O’Neal, B. J. (2022). Canada geese (Branta canadensis) nesting on elevated structures in urban Indiana, USA. Ecology and Evolution, 12(3), e8735. https://doi.org/10.1002/ece3.8735