Urban

Types of Urban Wildlife

"Urban wildlife species can be considered human obligates, associates, exploiters, adapters, or avoiders. These designations relate to the degree to which urban wildlife benefits from or is harmed by anthropogenic habitat change. Whereas some species are able to take advantage of human food subsidies or refuge from predators, others persist in human dominated landscapes by avoiding contact with people as much as possible.

Human obligates might not be considered wildlife by some because they are often domestic animals, however they play a major role in urban wildlife community composition. Obligates compete with, disturb, and most importantly, predate upon native species. Species interactions between obligates and natives greatly influence community function and diversity both in and on the fringes of urban development. Domestic cats in particular are known for their impressive predatory skills and their impacts on native and migratory bird species.

Human associates and exploiters are often generalist or omnivorous species that can take advantage of anthropogenic resource subsidies, or food supplied by humans. Human food sources can take the form of gardens, garbage, domestic animals, pet food, or other human exploiters. Exploiter populations in particular are able to achieve much higher numbers in urban areas than in wildlands due to the prevalence of available food. However, exploiters can also reach high numbers in developed areas due to release from predation or the ability to outcompete other native species in a novel environment (McKinney 2006). Relationships between exploiters and local residents vary; songbirds that use backyard feeders are often regarded positively, whereas predators that kill pets are likely to have negative associations. Property damage and disease transmission can also generate negative attitudes toward certain exploiters, including raccoons.

Human adapters are species that may utilize human resources and survive in human dominated areas, but do not necessarily receive an added benefit from living with humans. These species are often located on the periphery of development and may be relatively common in areas dominated by rural and exurban development. Adapters generally have not had a history of antagonism with humans and are often generalists that can use a wide variety of habitats. Deer are sometimes regarded as human adapters, as they can achieve high population sizes from wild areas to suburban habitats.

Human avoiders are not expected to use urban areas, but occasionally may find themselves amongst people when attempting to disperse or migrate. Avoiders often have either a history of conflict with humans or very specific habitat requirements for reproduction or foraging that are unattainable in human settlements. These species can experience high mortality rates or decreased reproductive rates in human dominated habitats. Mountain lions, for example, are human avoiders, but occasionally come into conflict with human communities by eating livestock or pets.

Disturbances & Threats To Urban Wildlife

"Urban ecosystems are often comprised of similar disturbances, including:

These disturbances can result in biotic homogenization, or the selection of the same animals that can tolerate human development and proliferate in urban landscapes across large spatial scales (McKinney 2006). Biotic homogenization threatens to favor the same generalist species in all cities, while diminishing populations of local endemics and specialists, which can be easily outcompeted by generalist and invasive species in disturbed habitats (Shochat et al. 2010).

Direct effects: Structure and function of the urban wildlife community is facilitated by differential responses to development and the degree to which species can utilize human resources. While some bat species are disturbed by anthropogenic light pollution (Stone et al. 2009), amphibians may be impacted primarily by loss of aquatic habitat or chemical runoff into waterways (Brand et al. 2010), and carnivores can be poisoned by the bioaccumulation of rodenticides (Riley et al. 2007). Other species have higher risk of disease in developed habitats due to higher population densities or interaction with domestic animals (Daszak et al. 2000). Large predators are at risk of decline due to spatial constraints and habitat fragmentation that decrease population size and genetic diversity (Bateman and Fleming 2012). Behavioral responses to development can inhibit wildlife from obtaining necessary resources or finding suitable mates for reproduction (Habib et al. 2006).

Indirect effects: Urbanization can alter interactions between species and therefore impact some species indirectly. Indirect effects often occur as a result of changes in the predator community (Prange and Gehrt 2004) or resource composition (Oro et al. 2013). For example, mesopredator release can occur with the loss of top predators, increasing predation pressure on native songbirds and small mammals (Crooks and Soule 2010). Anthropogenic subsidies can also produce indirect effects by decoupling predator-prey feedbacks (Rodewald et al. 2011).

Cumulative effects: Many anthropogenic impacts on wildlife populations are exacerbated by urbanization and development (Sala et al. 2000). For example, fragmenting the landscape by building roads and housing reduces the ability for species impacted by climate change to track their suitable climate envelope. Complex and cumulative effects of urbanization and other ecosystem changes therefore threaten to dramatically restructure wildlife communities." - Urban Wildlife Group

Solutions

Reducing Human-Wildlife Conflict

"One of the best ways to avoid human-wildlife conflict is to reduce attractants for unwanted animals. To reduce conflict with urban wildlife, residents can:

In addition we can focus on specific types of pollution that affect wildlife:

Expand Green Spaces & Reduce Landscape Pollution

Greenways and greenbelts can help reduce urban sprawl, provide green spaces for humans as well as pets and wildlife. They can help link fragmented places, reducing inbreeding or starvation of wildlife.

Community Gardens provide us with food and a place to connect, while wildlife can enjoy them for hunting, pollinating, breeding, and more.

Protecting or replanting riparian areas can go hand in hand with greenways and greenbelts. The trees growing either side of a water way specifically provides water access for wildlife as well as protection to the waterway from dangerous chemicals.

Reduce Light Pollution

Light ordinances can help protect wildlife from being blinded or confused by artificial lighting. Less light pollution means less cancer and other health problems in humans. Being able to see the night sky also means scientists will be able to see threats from outer space (such as asteroids) before they potentially crash into Earth. 

Projects/Solutions by Species

Bee Stops: Rooftop Pollinator Gardens on Bus Stops

Sometimes people get nervous about bees at ground level, but bees don't mind fouraging higher up, where people won't even notice them. This makes wall or vertical gardens, roof gardens, and pots on patios so perfect!

Hedgehog Highways

The Hedgehog Highway concept was created to help hedgehogs survive the increasing risks of habitat fragmentation which threaten many species. These little creatures waddle around gardens every night eating thousands of insects, and providing ecological benefits for us as we sleep. Around the world, similarly vital species are at risk of starvation, dehydration, or being unable to find mates and reproduce because of the barriers we put up in their habitats.

Even if you live in a country without hedgehogs, chances are that you have other wild neighbors such as possums, amphibians, mammals, and more who could benefit from similar environmental adjustments.

Resources

How to Help Hedgehogs

Hedgehog Highway Signs & Homes for Sale

Click the Hedgehogs button for more information including 3D printable hedgehog highway signs and other useful things.

Hedgerows

These not only help wildlife by providing food, shelter, and nesting materials, but they can protect us from air pollution. When planted next to schools, they can keep traffic pollution out of playgrounds, and when planted near other natural resources including parks, gardens, or waterways, they can function as part of a wildlife corridor.

Apps & Tools

Europe

UK

Resources & Guides

Nature-Friendly Gardening

Programs & Projects

Europe

UK

Organizations

International

Europe

UK

North America

USA

Minnesota

Texas

Oceana

Australia

Internship Opportunities

North America

USA

Illinois

Maps

International

Europe

UK

North America

USA

Grants & Funding

North America

USA

Missouri