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Species that are good at colonizing can utilize conditions provided by urban heat islands to thrive in regions outside of their normal range. Examples of this include Grey-headed Flying Fox (Pteropus Poliocephalus) and the Common House Gecko. Grey-headed Flying Fox, found in Melbourne Australia, colonized urban habitats following increase in temperatures there (confirm this characterization TL). Increased temperatures, causing warmer winter conditions, made the city more similar in climate to the more northerly wildland habitat of the species.

With attempts to mitigate and manage urban heat islands, Temperature changes and availability of food and water are reduced. With temperate climates, urban heat islands will extend the growing season, therefore altering breeding strategies of inhabiting species. This can be seen the best in the effects that urban heat islands have on water temperature. With the temperature of the nearby buildings sometimes reaching over 50 degrees different from the near-surface air temperature, precipitation will warm rapidly, causing runoff into nearby streams, lakes and rivers (or other bodies of water) to provide excessive thermal pollution. The increase in the thermal pollution has the ability to increase water temperature by 20 to 30 degrees. This increase will cause the fish species inhabiting the body of water to undergo thermal stress and shock due to the rapid change in temperature to their climate.

Urban heat islands caused by cities have altered the natural selection process. Selective pressures like temporal variation in food, predation and water are relaxed causing for a new set of selective forces to roll out. For example, within urban habitats, insects are more abundant than in rural areas. Insects are Ectotherms. This means that they depend on the temperature of the environment to control their body temperature, making for the warmer climates of the city perfect for their ability to thrive. A study done in Raleigh North Carolina conducted on Parthenolecanium quercifex (oak scales), showed that this particular species preferred warmer climates and were therefore found in higher abundance in the urban habitats than on oak trees in rural habitats. Over time of living in urban habitats, they have adapted to thrive in warmer climates than in cooler.

The presence of non-native species is heavily dependent on the amount of human activity. An example of this can be seen in the populations of cliff swallows seen taking nests under the eaves of homes in urban habitats. They make their homes using the shelter provided by the humans in the upper regions of homes, allowing for an influx in their populations due to added protection and reduced predator numbers.