The city is not the wild animal “desert” that scientists once feared


Some species, such as the peregrine falcon, have a higher survival rate or reproductive success rate in urban areas than in rural areas. Some people even prefer city views.A sort of 2017 analysis Of the 529 species of birds in the world, 66 species are only found in urban areas, including not only typical urban birds such as wild pigeons, but also various local birds such as burrowing owls and black orioles.According to another Review, Diversified communities of native bee species continue to exist in cities around the world, and in some cases, the local bee populations living in cities are more diverse and abundant compared to nearby rural landscapes.In Australia, researchers recently determine 39 endangered “last chance” species that only survive in small areas of urban habitats, including trees, shrubs, turtles, snails, and even orchids.

Over the centuries, urbanization has led to the massive removal and fragmentation of natural vegetation. After the initial shock, a complex new habitat mosaic composed of native, non-native and invasive plants appeared, dominated by buildings, roads and other impervious surfaces, and were contaminated.

Urban ecologists see these as a series of “filters” that make it difficult for many species to survive in cities, especially those with specific habitat requirements. For example, Myla Aronson, an urban ecologist at Rutgers University, points out that so-called azalea plants such as blueberries and azaleas that require acidic soil have disappeared from cities. She said that one possible reason is that concrete increases the alkalinity of the urban environment.

Although urbanization continues to pose a major threat to species and ecosystems, cities are full of “very diverse” unconventional habitats that “can provide important habitats or resources for local biodiversity,” wrote Scientists from the University of Melbourne in a 2018 paper Conservation biologyThese range from remnants of primitive ecosystems, such as forests, wetlands, and grasslands, to traditional urban green spaces, such as parks, backyards, and cemeteries, as well as golf courses, urban farms, and community gardens. In addition, as cities invest in green infrastructure to reduce environmental hazards, wild animals are increasingly occupying new niches, including green roofs and constructed wetlands, and colonizing former brownfields and open spaces. The positive role that cities play in promoting biodiversity “can be enhanced by deliberate design,” the authors of the report wrote. Biology Article on the “Biological Desert Fallacy”.

In recent years, urban ecologists have opened up a new field in the field of conservation biology. A groundbreaking paper published in 2014 analyzed 110 cities in a series of biogeographic regions, including a comprehensive list of resident plant life, and 54 complete bird lists.according to learn, These cities retain most of the native biodiversity. However, Aronson, the first author of the paper, and her colleagues also found that the number of plants and birds in the cities they studied has become less, losing 75% and 92% of the pre-urban density, respectively.

Another founding Paper Published two years later, “Urban Conservation Biology” was written by Australian scientists who found that the city has 30% of the country‚Äôs endangered animals and plants, including the Carnaby black parrot, a large-scale social parrot that only lives in southwestern Australia. Agriculture has fragmented most of its habitat. In fact, they found that cities contained more threatened species per square kilometer than non-urban areas. They wrote: “Australian cities are important for protecting endangered species.”

Scientists have describe Urban areas can benefit regional biodiversity in many ways. For example, cities can provide refuge for local species facing pressures such as competition or predation in the surrounding landscape. The greater density of prey in the city is related to the success of several urban birds of prey, including the Cooper Eagle, Peregrine Falcon, Crested Goshawk, and Mississippi Kite. The city can also be used as a stopover for migratory birds to rest and refuel. Large urban parks, such as Highbanks Park in Columbus, Ohio, provide important stopover habitats for thrushes, warblers, and other migratory songbirds.


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