Urban Gray Squirrels

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Urbanization is an obvious problem for multiple species of wildlife. Dependency on humans, and boldness are two of the largest effects urbanization has on species. One species in particular being the Eastern Gray Squirrel. From eating bird feed from backyards, to eating out of people’s hands, it shows that they have shifted from their natural avoidance of humans. A study conducted in Boston Commons, a 50 acre urban park in downtown Boston, shows this perfectly.

The study conducted on the boldness of the Eastern Gray Squirrel divides Boston Commons into 5 sectors, two of which had dense tree cover, while the others contained mostly grassland and scattered trees. All quadrants are surrounded by roadway, so noise pollution and distractions could be factors in results. The experimenter in the study observed squirrels in each quadrant 3 times for periods of 20-60 minutes throughout the month of March. It is important to note that this is around spring breeding times for squirrels, and could see increased activity and boldness. The experimenter observed squirrels feeding, how quickly the squirrels fled, how bold they were, or if they were conducting other activities. 

It is important to understand that this study has many flaws. One being that it is only a regional study, in a park setting. Boston has vastly different weather conditions in March than in say the Midwest. Only being a regional study, it can be hard to determine if the behavior in that specific region can correlate to different environments. Not only that, it is important to realize that another flaw in the sampling is that the study is at a time of peak activity, and no other time of the year. Squirrels breed and produce young between February and May. What if another study was conducted in July, when temperatures peak? Lack of consistency is also important to consider. A human body was introduced when seeing how bold the squirrels would be when presented with a nut in a hand. Some squirrels took it, and some didn’t. Humans aren’t perfect, and there is no control group in the study.

Overall the study does a great job of highlighting the problems of urbanization for squirrels. In the wilderness, a squirrel will not just walk up to an out of place object, a human, and accept a nut from their hand. It is just not realistic in their natural environment. An urban squirrel taking a nut from hand not only shows they don’t fear natural predators anymore, but they may be becoming dependent. No study is without flaw, and I think this could be a great resource in future research, to help raise awareness about problems of species urbanization.

Light pollution is the fastest growing potential threat to firefly conservation in the Atlantic Forest hotspot

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Link: https://resjournals-onlinelibrary-wiley-com.prox.lib.ncsu.edu/doi/10.1111/icad.12481

Light pollution is an increasing threat to firefly populations. Due to the aspect of sexual attraction in the process of this species mating behavior. Although fireflies are also harmed by habitat loss and urbanization, light pollution is hard to mitigate. This paper is interesting in that it compares the damage from different sources that implement harm on firefly’s to highlight the most alarming threat. Moreover, I remember as a kid there would be so many fireflies outside at night that my friends and I would catch with our hands and admire how they could produce light. This article modeled the possible distribution of the tracker ghost firefly Amydetes fastigiata and determined the rate of growth for light pollution, urbanization, and deforestation in the Atlantic Forest.


This study was conducted in the Atlantic Forest. The light pollution data was collected by analyzing a data set on harmonized global nighttime light observations from 1992-2018.Then the urbanization and forest cover trends data were collected by using MapBioMas Collect 5 to analyze the distribution of the ghost firefly from 1992-2018. To compare the first and last 5-year time frames of this data set the researchers calculated mean values and other statistical analysis to find the percentage of land cover, pixel numbers, etc. The researchers performed the Cramer’s V test to find associations between the split data set. I believe that the data analysis could have included some self-observations from the researchers of at least a year’s worth of data to add it to the analysis of the data set from 1992-2018. However, the researchers did compile entomological collections, literature, and field work data. Therefore, with the understanding that research has limitations based on funds, the self-observations for at least a year would not have been a priority; it would have just added another year of data collection.

The authors’ findings showed that light pollution had the greatest rate of growth in the study site. Approximately 1,4000 km2 of dark areas were found to be impacted by artificial light. It was emphasized that the main reason that light pollution outdoes the other threats in the speed of growing concern is that it is difficult to cut off the light’s reach. Unlike how protected spaces allow there to be a buffer between urbanization and deforestation. Light pollution is a challenging matter especially to nocturnal insects that are most vulnerable to the changes it implies. The discussion does a great job in explaining the different vulnerabilities to fireflies. For instance, to the males using the light signaling to detect females. The activity of the light flashes are reduced lowering reproductive opportunities. Furthermore, larvae are left with both decreased defense mechanisms and effectiveness as predators. Since, larvae use aposematic signals under bioluminescent communication. Additional variable that should be considered is that given that more than 60% Brazil’s population lives within the Atlantic Forest that the visits from the growing number of people to the areas that the fireflies reside on may be damaging the larvae, capturing fireflies for entertainment purposes, etc.

This study brings attention to artificial light being the top stressor to fireflies and the challenges of mitigating it. In addition, to the need for adapting regional conservation policies and locations of protected areas. The framework that the research created can help future research pinpoint areas of improvement for vulnerable populations of species. The study found that deforestation had the greatest extent of effect on firefly’s however, pointing out that light pollution was found to be an emerging concern which directs future research. It is important to know that further growth of light pollution comes from habitat loss for new developments that changes the land use.

Critical Review of global trends in urban wildlife ecology and conservation- Cecille Ernst

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In September of 2021, Merri K. Collins, Seth B. Magle, and Travis Gallo conducted a literature review of peer reviewed and scientific primary literature sources that had to do with urban wildlife from 2011-2020. In a previous literature review from 2012, Dr. Magle performed a similar review of primary literature articles from 1971-2010 also looking into urban wildlife. The original Magle paper found an increase in papers from 1971-2010 having to do with conservation, with the new paper finding an even larger increase.

This paper used literature criteria along with key words in order to find the sources. They searched on World of Science in the most high journals, along with the word urban, exurban, and periurban, but limited the search to just primary literature. They then organized their data into categories based of of areas of study, including animal behavior, conservation, ecology, general science, landscape ecology, and wildlife biology. They then broadened their search by using Google Scholar, and including the term wildlife with urban. They ended up adding spatial ecology and social science as two more areas of study in order to acomodate for the increase in articles written in those disciplines.

Once they collected all of the literature sources, they placed them into a table side by side with the table from the Magle paper from 2012. The data was the translated into a graph in order to show the extreme increase in urban wildlife papers since 2010, and can be found below.

This graph shows the uptick in publications from 1971-2020, but specifically from 2011-2020. In the original Magle paper, Magle has hypothesized this increase, and from the new paper, they expect an even greater increase.

The paper found the highest proportion of papers to be in the animal behavior discipline, followed by conservation, and then wildlife management. Mammal studies were the most common found, followed by bird studies. These scientists also made note of the fact that many of these articles came from North America, followed by Europe, with very little coming from Africa, South America, and lastly Asia.

After reading this literature review, I am hopeful that more and more research is being done in the urban wildlife field, especially in conservation. I do believe though that we need more research in areas that are underrepresented, along with more articles that are written in a more interdisciplinary way, as many of these issues can be tackled from different perspectives. I think it is interesting that animal behavior was the most common discipline articles were found in, as I would have originally thought it to be wildlife management.

I think that literature review papers can be very beneficial for public education, as they allow everyone to read, visualize, and understand trends in conservation and urbanization. Considering the majority of the population is projected to live in urban areas by 2050, it is important for people to learn the impact that this has on our natural lands and ecosystems. More wildlife biologists are focusing on urban wildlife research, which can only help us in the long run.

Merri K. Collins a, et al. “Global Trends in Urban Wildlife Ecology and Conservation.” Biological Conservation, Elsevier, 10 July 2021, www.sciencedirect.com/science/article/pii/S0006320721002883?casa_token=wYjg9uqo7sEAAAAA%3AXrA2S7D3aXz-rFSMBOzzI2JZXAsajrJFv8pk2uBBjEw-DX2CFM0gQHoYieIjrKYc_It00-ev-Voh.

Greater consumption of protein-poor anthropogenic food by urban relative to rural coyotes increases diet breadth and potential for human wildlife conflict

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We have all seen it, news articles on human wildlife conflicts with coyotes. These are never good interactions as most of the time coyotes are attacking someone’s pet. Sometimes you see videos of a coyote catching a squirrel and people get mad at the coyote for doing so. Why? He has to catch his own meal. He would be doing the same thing in the woods where you can’t see them. This article studied the effects on anthropogenic foods on urban and rural coyotes and tried to find a correlation with the coyotes that caused conflict and their anthropogenic food consumption and overall health.

Urban coyotes that were studied came from Edmonton and Calgary in Alberta, Canada. Rural coyotes came from Elk Island National Park and Ministik Lake. Elk Island National park is a fenced park and Ministik is a bird sanctuary closed to the public. Scat collection was a way they were studying food choices by coyotes in all locations. Edmonton produced 531 scats and Calgary produced 484 scats. Calgary was collected between 2006-2007 and Edmonton was collected between 2009-2012. I am not sure why they were collected this many years apart and I believe they should have been collected more closely in time. Cities can change a fair amount in 6 years and that can change the diet of these carnivores. Elk Island had 1221 scats and once again a big time difference; these were from 1994-2000. There was no scat collected in Minisitk but collected from Wasbasca, a nearby town that allowed the public to enter. In my opinion, none of this collection seems very consistent as many things can change in that wide of a time period. Hair collection was another way data was collected. It turns out you can understand an animals diet by examining different parts of their guard hairs. Hair was from live-trapped animals or from deceased animals via car collisions or hunting.

The results were similar to what one would expect. Urban coyotes had a more diverse diet than rural coyotes. Shocker right? But urban coyotes did contain more species diversity in their scat than did rural coyotes. This is likely due to pets and other urban-centered critters that have better success living in urban environment than a rural environment. Urban coyotes that were reported for conflict had diets that contained more of anthropogenic food sources, had a lower body class score and more likely had mange than rural coyotes. None of the rural coyotes reported appeared to be unhealthy. Contrary to what the media shows us, coyotes predated less on pets than other mammal classes. Urban coyotes predated more on smaller mammals than rural coyotes did but predated much less on larger mammals than rural coyotes do. Out of the urban coyotes that were reported were involved in a human-wildlife conflict, all of them showed signs of low body score or have a manage infestation. Rural coyotes reported in human-wildlife conflict all appeared healthy. Urban coyotes reported had a much lower protein intake and higher anthropogenic intake than rural coyotes.

Urban coyotes were shown to have a much higher diversity in caloric consumption than did rural coyotes. They proved that pets are one of the lowest predated on groups by coyotes no matter in urban or rural locations. Coyotes in an urban environment that were reported had lower quality health and were more likely to be to weak to hunt properly or were sick with mange. I was very intrigued in this research with my business being heavily revolved around human-wildlife conflict. Coyotes is a very common call I experience and it is likely they are feeding on pet chickens that are free ranging or just roaming through the yard. Rarely are they seen trying to attack any pets. I would have preferred that their data collection been closer together in time period. Having a range from 1994-2012 is a large time period and lots can change in an area resulting in change to a species’ diet and actions.

1. M. Murray et al., Greater consumption of protein‐poor anthropogenic food by urban relative to rural coyotes increases diet breadth and potential for human–wildlife conflict. Ecography. 38, 1235–1242 (2015).

Critical Review of “Human–wildlife interactions in urban areas: a review of conflicts, benefits and opportunities”

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As a rapidly urbanizing global society, there are more and more interactions between wildlife in urban areas. Urban ecology has been a relatively new field of study since its inception in the 1960s, with its initial focus on the negatives of human-wildlife interactions: disease transmission, nuisances, property damage, and direct conflicts resulting in injury or death. More modern research details the positives of urban wildlife interactions, such as keystone species and ecosystem services such as supporting, provisioning, regulating, and cultural). The perception of these interactions is greatly determined by the social and cultural factors within a given community. This paper summarizes the general body of research surrounding urban wildlife conflicts, detailing the extent to which they expand our understanding and the gaps and limitations of the studies. 

The paper’s overarching objective to demonstrate the effects of one’s societal context on perceptions of urban wildlife interactions was one of the largest takeaways I had from this critical review. The discrepancy between the perceived dangers and damage to property of urban wildlife interactions far exceeds the real likelihood, prompting many to eradicate species, hindering conservation efforts, and making poorly informed management decisions. Urban wildlife conflicts have more to deal with social and cultural factors than reality itself; the authors indicate the need for a more interdisciplinary framework in which urban wildlife conflicts are studied. More collaboration with economics, public health, sociology, psychology, and planning experts is necessary to gain a better understanding. 

In addition to improving the framework from which researchers approach urban wildlife conflicts, there is a need for better education about their true nature. A larger focus on the benefits of the interactions between wildlife, such as mental health benefits, is necessary. In a rapidly urbanizing world, people are becoming more detached and disenchanted from the natural world, which is associated with more mental health issues. An increasing body of research indicates the benefits of nature-based therapy, which public health officials overlook; they are more concerned about the individual’s lifestyle than the environment they are constrained to. Better education would midgate hysteria, increase the value society places on urban wildlife, and midgate poor management decisions.

Another takeaway from this paper was the unintended consequences of urban greening initiatives. Urban greening projects have the unintended consequence of creating a high disease hazard, even more so with projects to connect fragmented habitats through corridors. Improved green infrastructure can also increase the frequency of wildlife-vehicle collisions. The positive impacts of urban greening can not be overstated, but mitigating wildlife disease transmission and collisions should also be mitigated, which are not mutually exclusive. 

As a result of this critical review, my perspective on the body of research on urban wildlife interaction has broadened. I am more aware of the current gaps and limitations of existing research. In the same way, ecology seeks to unravel the complexities of the interactions between organisms. Still, urban ecology faces greater complexity as cities function as an ecosystem. An ecosystem with its own identity is influenced by countless factors such as culture, history, economy, and environmental interactions. This paper reinforces the importance of a multidisciplinary perspective within urban ecology. As a researcher, I find this paper incredibly helpful as it indicates research gaps that must be explored and expanded upon.

Source: Soulsbury, Carl D., and Piran C. L. White. “Human–Wildlife Interactions in Urban Areas: A Review of Conflicts, Benefits and Opportunities.” Wildlife Research, vol. 42, no. 7, July 2015, pp. 541–53. bioone.org, https://doi.org/10.1071/WR14229.

I utilized Grammarly during the completion of this assignment.

Factors influencing distributional shifts and abundance at the range core of a climate-sensitive mammal

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It is quite known that bees are one of the most famous pollinators, as they are said to be one of the top pollinators. Many factors such as pesticides, introduction of pathogens, climate change and habitat fragmentation all negatively affect bees. But one factor, urbanization, seems to be still understudied. It seems that there is a mix of both negative and positive effects on bees with urbanization. Social bees seem to thrive in urban areas and have an increased survival, while bees that nest in soils seem to be negatively impact. With this study its objective was to determine how urbanization and plant availability affect the richness, species abundance, functional characteristics and composition of bee communities in medium-sized cities.

The study area were 6 cities located in Brazil (southern Minas Gerais, Brazil: Alfenas, Poços de Caldas, Pouso Alegre, Varginha, Três Corações and Lavras, figure below). The cities were primarily made up of urban ecosystems made up of x<170000 inhabitants, agricultural landscapes, and forest area. 21 locations were selected across the 6 cities selected, with each location having an increasing gradient of impervious coverage (Figure below). To evaluate bee community, an active capture method was used to sample the bees in the cities. Sampling was performed within a radius of 200m from the central point of each location. Bees were collected on each plant for an approximate of 10 minutes. If 5 minutes passed and no bee were observed then the next plant was observed. Sampling of plants was also performed during sampling of bees. Bees were characterized under 3 functional groups, these groups being social behavior, nesting habit, and trophic specialization. Social behavior had 3 subgroups highly eusocial, primitively eusocial and solitary. Nesting habit had 2 groups above ground nesting and below ground nesting. For trophic specialization 2 groups were considered, they were generalist or specialist.

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From this study it found a total of 4279 bee specimens that belonged to the 5 subfamilies that occur in Brazil (Andreninae, Apinae, Colletinae, Halictinae and Megachilinae). In order the richness of the bees were Apinae, Halictinae, Megachilinae, Andreninae, Colletinae. Regarding plants a total of 858 plants of 190 species were found.

It was found that the total bee richness was mainly affected by impervious cover, grass cover, and landscape heterogeneity with a radius of 750m and 1000m. Impervious cover showed a negative effect on total richness in 1000m, while landscape heterogeneity showed a positive effect for 750m and 1000m. Grass cover was deemed important and was show in the models. (Figures below)

Richness of above ground nesting bees and generalist bees were influenced positively by the diversity of landscape radius of 750m and 1000m. The abundance and below ground nesting bees was influenced positively by an increase of grass cover in the 1000m radius.

The models that helped explain the bee community diversity to plants is added below.

Overall the study found that an increase of impervious cover led to a decrease of bee species richness, especially affecting ground nesting bees. But solitary bees abundance increase as grass cover increased. It found that greater landscape diversity in urban areas support species richness. The study helps argue for the need of habitat diversity and native plants for bees in urban environments.

I overall really enjoyed reading this study as I enjoy reading about insects and their relation to conservation, ecology, etc. Reading this study made me wonder what urban designs could help promote bee richness or promote the bee populations. I believe that if more bee friendly designs were implemented it could definitely help improve the species. Maybe a structure that could help solitary bees when an increase of impervious surfaces are abundant. I also wonder how this study would be in areas that have a higher urbanization rate. Would the results be similar or would the results be drastically different?

Tavares Brancher, K.P., Graf, L.V., Heringer, G. & Zenni, R.D. (2024) Urbanization and abundance of floral resources affect bee communities in medium-sized neotropical cities. Austral Ecology, 49, e13299. Available from: https://doi-org.prox.lib.ncsu.edu/10.1111/aec.13299

Light Pollution & Migratory Birds (Please grade this one Dr. Katti)

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https://www.sciencedirect.com/science/article/pii/S0169534722003329

Ever since the dawn of time several thousands of years ago, there has been light. Along with that light there have been thousands of species affected by such light. Although known that light pollution causes wildlife conflicts, according to the authors, “…artificial light was only referenced as a pollutant and entered the lexicon of peer-reviewed scientific literature in the past 50 years…” Commonly confused with astrological light pollution, light pollution with effects on wildlife was coined, “ecological light pollution.”

In the study it is reported that lights are not the specific cause of death to the migratory species, but alter the behavior of said species in dramatic ways. Artificial light can disrupt migration patterns, and timing. But, it is not just during the night that this occurs, as the authors presented claims that lights during the day may be a cause of bird collisions. We know that birds often collide with buildings during the day, as I have seen it happen, but is it specifically lights being the cause? Not only has it been reported that light affects migratory birds, but some insects as well have been known to be attracted to light. Moths and grasshoppers being some of them.

The article presents an interesting idea that there are three main areas of conflict that wildlife, specifically migratory wildlife, face when it comes to light pollution. That being on the macro scale, the regional scale, and the local scale. The local scale being your cities, individual structures, and sometimes even vehicles. The regional scale being obviously based on what region it is in, most specifically areas of major migration (flyways). And macro being large scale, like hemispherical regions. 

The authors of the article don’t do a very good job in explaining the study method. Yes, it is understandable that it is hard to study wildlife deaths due to light pollution because there is no control. You can’t physically have a control group in the study. It was just acknowledged how many birds were found dead throughout a certain period in a certain area. The article reports that 40,000 birds have been recorded dead by collisions with lighted buildings since 1978. It is also important to acknowledge that the authors understand the lack of control group, and the lack of organization in the study. The information was very hard to understand as well, as it was organized in a complicated manner for me.

Overall, the authors presented what evidence they had, and the potential reasonings why. Although the evidence may be collected in a non-controlled manner, I still think the article and study both serve the purpose of presenting the case of light pollution and its effects on wildlife.

Carolyn S. Burt, Jeffrey F. Kelly, Grace E. Trankina, Carol L. Silva, Ali Khalighifar, Hank C. Jenkins-Smith, Andrew S. Fox, Kurt M. Fristrup, Kyle G. Horton,
The effects of light pollution on migratory animal behavior,
Trends in Ecology & Evolution,
Volume 38, Issue 4,
2023,
Pages 355-368,
ISSN 0169-5347,
https://doi.org/10.1016/j.tree.2022.12.006.
(https://www.sciencedirect.com/science/article/pii/S0169534722003329)
Abstract: Light pollution is a global threat to biodiversity, especially migratory organisms, some of which traverse hemispheric scales. Research on light pollution has grown significantly over the past decades, but our review of migratory organisms demonstrates gaps in our understanding, particularly beyond migratory birds. Research across spatial scales reveals the multifaceted effects of artificial light on migratory species, ranging from local and regional to macroscale impacts. These threats extend beyond species that are active at night – broadening the scope of this threat. Emerging tools for measuring light pollution and its impacts, as well as ecological forecasting techniques, present new pathways for conservation, including transdisciplinary approaches.
Keywords: artificial light at night; avian; light pollution; human–wildlife conflict; migration

I

Critical Review of Drivers of Plant Biodiversity in Urban Areas

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https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1202115/full

The article I chose to critically review discussed the drivers of plant biodiversity in urban landscapes. Before opening the article, I had a very vague outline of the drivers, but didn’t really know enough to teach someone about the subject. They do a great job discussing Urban Green Space, and how those spaces function inside of an Urban Functional Unit. This is something important to discuss because come to find out, the presence of Urban Green Space is single handedly one of the largest drivers of plant biodiversity.

The authors describe their experiment as taking small test plots, a different size for each type of plant they are looking to collect data on. I think this poses a problem with some of the results. By surveying a large plot for the number of trees vs a smaller plot for the number of shrubs and herbaceous, there could be a big difference in the number of plants, and the standard deviations across the various plots. The reasoning behind this may be due to the fact that trees cover significantly less surface area than some shrubs or herbaceous vegetation, but I think it is more important to keep a constant in the study, which the scientists failed to do.

Another thing that I find interesting is the failure of the scientists to post somewhat readable data. All of the visual charts that the scientists posted in the article were very hard, almost impossible to read. This very well could be a technology failure and not a failure of the scientists, but it is a very interesting thing to make note of.

The thing the authors do really well is laying out the information found in the study very clearly. They make sure that each individual driving factor is explained really well, and give ample reasoning why each driving factor is a driving factor. It is laid out very clearly as well, and is easy for someone who may not be used to reading scientific information, especially myself. 

Overall, the authors did a really good job of writing the article. There may be some questions about the process of surveying the plants, but the factors that were done well supersede those in my opinion. It was easy to understand, and yielded a happy reader with more understanding of the topic.

How to add a new blog post

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Hi everyone, I am Dr. Madhusudan Katti, your professor for the FW 403 / NR 595 Urban Wildlife Management class. Here are the step-by-step instructions on how to add content to the class blog.

  1. Go to Moodle main page and click on the link for “Current Class Blog”. 
  2. You will see a screen below and then log in to WordPress using your NCSU account.

3. Once you logged in, you should be able to see WordPress below. Then click on “+ New” to add a new blog.

4. Next, you can edit the contents for your blog and choose a category on the right-bottom corner. There are two categories for you to choose, either a Class Discussion Report (the reflection blog post) or Critical Review.

5. Rember to click “Publish” on the right-up corner and check the class blog again if it works.

PS: you can also access the class blog through WolfWare. Right next to the “Moodle” icon, click “WordPress” and the rest is the same as instructed.