2315ENV Urban Ecology and Biodiversity Task
Question: What are the Characteristics of a Successful Urban Species?
Depth of the Published Research
Urban wildlife animal communities consist of species that use human-dominated ecosystems. The world is rapidly changing from a rural environment to an urban environment. The rapid transitioning of the world from a rural to the urban environment has been causing shifts in ecology, habitat, and biodiversity (McKinney, M. L. 2002).
Urban ecologists focus their research on birds when testing for the effects of urban environments on wildlife survival. Research results by Kark’s reveal that “Urban adapters and exploiters primarily differ in the migratory status and social structure: urban adapters are less social to species when compared to exploiters” (Kark et al., 2007).
Clear trends have also been witnessed for dietary preferences along a gradient of increasing urbanization in Jerusalem, in that, as urbanization increases, the ratio of granivorous species also increased whereas the number of species that feed on invertebrates keeps reducing (Kark et al., 2007).
On the other side, neither relative birds size of brain nor their behavioral flexibility, as determined through feeding innovations, significantly varied among urban exploiters and adapters in Israel (Kark eta l., 2007).
The conclusions of Kark’s ecological article are that being successful in more versus less urbanized settings in a city is not necessarily a factor of the size of brain nor the flexibility of a species behavior; rather this depends on a combination of characteristics that comprise of diet, social environment, sedentariness and preferred shelter by the birds (Kark et al., 2007)
Finally, the pattern in which well-adapted species to human-dominated landscapes (urban exploiters) is replacing a broader range of native species is constantly repeated in most world regions, and this is termed as biotic homogenization (Kark et al., 2007).
The essay aims at explaining the characteristics of successful urban species.
Characteristics of Successful Urban Species
Urban species survive in the city landscapes due to various attributes. Successful urban species are considered to contain a higher tolerance of human behavior disturbances. Urban ecologists argue that successful urban species have the ability to change their behavior and adapt to major rural to urban environmental disturbances and changes (Ditchkoff, Saalfeld, & Gibson, 2006). Also, these species are considered to be strong competitors and able to exclude themselves from the native species. Further, successful urban species are believed to be generalists with regard to habitat and food, and may consume human food sources such as pet food, garbage, and birdfeeders. Based on this brief, the main characteristics of a successful urban species include:
Habituated to the presence of humans
In order to survive in urban environments, species should be habituated to the presence of human beings. Human presence is vital to the survival of birds in the urban environment. Currently, urban forestry is increasing and this is vital for urban species conservation and survival. Birds within the geographies of human presence tend to survive better in the urban areas as compared to those species habituated to the absence of humans (Shochat et al., 2006). Urban forestry forms habitat for urban species such as birds. Where human population is large, environmental conservation initiatives are manifested. Ecological scientists argue that the greater the attention to vegetation covers in the urban areas is the greater the number of species in the ecosystem. Human pay great attention to urban development, and are keen on reducing environmental disturbances such as pollution. These initiatives favor the wellbeing of urban species hence increasing their survival. Further, the interactions between wildlife and humans have grown and this has expanded the rate at which urban species adapt to living in human-dominated environments (Shochat et al., 2006). These interactions benefit the wildlife in that humans feed them. Human-wildlife habituation also enables urban species survive in these environments. In this regard, the habituation of urban species to the presence of humans is a major characteristic that makes these species survive in urban areas.
Exceptionally broad diet
Species living in urban environments have exceptionally broad diets that make them survive. Most urban species utilize human food sources such as garbage, birdfeeders, and pet food. Also, most successful urban species are typically omnivorous and generalists with regard to food and ecosystem (Oro et al., 2013. The urban areas are full of food leftovers thrown to garbage as waste; birds in the city together with other species consume this as their food. Pet food also forms urban species diet, and this is easily obtainable by the species. Other urban species survive on junk foods thrown by people in the city. Ecological scientists claim that urban species rely on humans for survival. These ascertain may or may not be true when it comes to their diet. Human food sources form the primary diet for the urban species. However, some species are able to search for their own food in the ecosystem. Where there are human dwellings, urban species diet is plenty. Availability of food prevents starvation and death of the species, and this makes their numbers to keep on increasing in the urban ecosystem (Prange & Gehrt, 2004). In this perspective, the urban population of birds, wildlife, and other species such as crows and Ravens continue to increase. Exceptional and broad diet to the species enhances their survival in urban environments.
Surviving under non-natural environments of the city requires the species living in such environments to adopt new feeding techniques such as feeding on novel food items. Also, these species have the ability to transform their behavior in order to adapt to major environmental disturbances and changes. This plasticity promotes the invasion of novel habitats to the new species by offering them with the ability to expand their ecological niche or gap, and this contributes to the long-term survival of the species in the city. The body of these species has the ability to survive in different ecological environments (rural and urban). Behavioral flexibility by a species greatly contributes to its survival in the city ecosystems since they are able to adjust even their feeding mechanisms and still survive without stress. The transition from rural to the urban environment is difficult for some species to adapt. However, species that survive in the urban habitats show great flexibility in terms of environmental disturbances and feeding habits/mechanisms. Also, these species have the ability to deal with invasion pressures and threats in the new ecosystem hence their survival.
In order to survive in non-natural environments of an urban area, species living in such environments should adapt the characteristics of other species living in that environment. Successful urban species exemplify a shift in their functional traits during the rural-urban transition. The ability to learn new attribute that species did not possess in its native environment enables it to successfully survive in the urban environment (Prange & Gehrt, 2004). Most traits of urban species are pre-adapted for invasion. Invasive species survive better in urban cities than the native species due to more nutrients, diet, and conservation by humans in the cities. Such species are able to withstand new invasions in the new environments. As a result, they learn how to defend themselves from environmental threats in the urban areas hence increased survival. The aspects of nature are flexible and conceivable in the urban setting, and this makes new species adapt and cope with environmental changes and threats appropriately. Successful urban species also easily learn from the rest on how to live and defend themselves against invasions, and this boosts their survival (Prange & Gehrt, 2004). Due to this, biological and environmental diversity is enhanced whose fruits are manifest on the increased population numbers of new species in the cities.
Don’t show stress
Recent research shows that birds, wildlife, and other urban species show no stress while living in the cities ecosystems. Ecological scientists argue that stress leads to premature death of urban birds and other species. However, most urban birds and wildlife do not show stress and this prevents them from premature deaths. Today, urban birds, wildlife, and other species living in the urban area have longer telomere than those species living in the rural areas (McKinney, 2002). According to environmental researchers, lack of induced stress on urban tits results to longer telomeres and thereby increasing chances of living longer. In this regard, birds and other species living in the urban areas enjoy perceptual diet sources, environmental conservation, and habitat development from humans living in the cities. With enough diet and shelter, the species have no stress hence living longer something which is increasing their population number/size in the urban cities (McKinney, 2002). The psychological functioning of successful urban species is unique and contributes to their survival in the urban environment. The harmful stimuli are prevented in the cities by human measures; birds and wildlife live with no fear and anxiety of their survival. As a result, this increases their chances of survival in the urban environment.
Have big brains
Research shows that birds with bigger brains tend to position themselves in urban environments more strongly than birds with smaller brains. Birds with larger brains have a larger ability to tolerate human disturbance and compete strongly for survival in the ecosystems. Biodiversity scientists have discovered that birds with stronger brains are better able in colonizing inhospitable places (Shochat et al., 2010). Where the urban environment is disturbed by human activities, brainier birds use their pre-adaptive benefits and mount quickly in the ecosystem. Cognitive buffer hypothesis by brainier birds makes them feel flexible on their behavioral responses to unexpected and constant environmental changes. Such big brains in birds provide them with urban survival advantage. For example, the likelihood of hunters killing brainy birds is low when compared to their likelihood of killing less brainy birds. Species evolution is making them brainier hence increasing their chances of survival in the environment. In this regard, the most hunted species by hunters have turned brainier, smarter, and better able in escaping the catapults and guns used to kill them than protected species (Shochat et al., 2010. However, it has been difficult to test the validity of this idea by researchers for it is subjective to tell the brainier and less brainy species in the ecosystem.
Form large species
Recent research by ecological scientists reveals that species that form large groups successfully succeed in urban environments. The formation of a large common species in the ecosystem contributes greatly to its survival. Species form the largest group of organisms in which two can reproduce. Due to the formation of large species, reproduction increases and new species are born a day after another (Prange & Gehrt, 2004. The increased reproduction in the ecosystem increases the number of species in the urban areas. Some species like lorikeets reproduce regularly and this forms a larger group of the species. As a result, large groups are formed in the environment. The ability of different species to reproduce makes them form respective species groups hence increased survival in the ecosystem. A large formation of species in the urban area contributes to easy species growth in the urban cities.
My Own Ideas
In order to preserve biodiversity, conserve ecosystem function, enhance positive associations with wildlife, and foster safer ecosystem; the study of urban species helps humans understand stressors on species interaction and survival in the cities environment. Many species persist in urban environments despite increased impacts on wildlife ecology by humans. Understanding which species thrive and survive in urban areas or what makes them thrive in such environments is an important topic of research. The major types of urban wildlife are human obligates, human exploiters and associates, human adapters, and human avoiders. The major threats and disturbances to urban species are habitat loss, habitat fragmentation, invasive species, noise and light pollution, and chemical runoff and pollution. I acknowledge that the ability of these species to tolerate human presence greatly enhance their survival and wellbeing in the urban areas. Successful urban wildlife possesses exceptional attributes, and this is why their survival is enhanced. Urban species have the characteristics of tolerating human disturbances, adapting to environmental changes, consuming human food sources, strong competitors, free of stress, and of bigger brains among many other attributes. Therefore, these are the characteristics of successful urban species.
In conclusion, urban species portray unique characteristics that enable them survive in the urban environments in a more comfortable manner. Urban species have the ability to survive in different environmental settings with little or no stress given their big brains especially when dealing with an enemy. The closer association of urban species to humans enhances their survival in the cities. Also, the exposure to humans acts as a perfect opportunity for the urban species to have food which is considered as waste by people. Further, these species are behaviorally flexible and this makes it easy for them to withstand any human disturbances in the ecosystem. Additionally, urban species show a great preadaptation deal to new ecological environments and this enables them survive in the new urban environments easily. Furthermore, their ability to reproduce enables them form larger species and population in the urban centers. Finally, there is need for humans to properly associate with urban species since this promotes biodiversity and growth in the ecosystem.
Ditchkoff, S. S., S. T. Saalfeld, and C. J. Gibson. 2006. Animal behavior in urban ecosystems: modifications due to human-induced stress. Urban Ecosystems 9:5–12.
Kark, S., Iwaniuk, A., Schalimtzek, A. and Banker, E. (2007). Living in the city: can anyone become an ?urban exploiter’?. Journal of Biogeography, 34(4), pp.638-651. https://bblearn.griffith.edu.au/bbcswebdav/pid-3673579-dt-content-rid-21710308_1/courses/2315ENV_3181_NA/Living%20in%20the%20city%28Kark%292007%281%29.pdf
McKinney, M. L. 2002. Urbanization, biodiversity, and conservation. BioScience 52:883–890.
Oro, D., M. Genovart, G. Tavecchia, M. S. Fowler, and A. Martínez-Abraín. 2013. Ecological and evolutionary implications of food subsidies from humans. Ecology Letters 16:1501-1514.
Prange, S., and S. D. Gehrt. 2004. Changes in mesopredator-community structure in response to urbanization. Canadian Journal of Zoology 82:1804–1817.
Shochat, E., S. B. Lerman, J. M. Anderies, P. S. Warren, S. H. Faeth, and C. H. Nilon. 2010. Invasion, competition, and biodiversity loss in urban ecosystems. BioScience 60:199–208.
Shochat, E., P. S. Warren, S. H. Faeth, N. E. McIntyre, and D. Hope. 2006. From patterns to emerging processes in mechanistic urban ecology. Trends in Ecology and Evolution 21:186–191.