Greater Prairie Chicken, photo: Teo via flickr
The newly released 2009 State of the Birds report catalogues just how much pressure birds in the United States face. For the first time, data from a wide variety of sources has been pulled together and presented in an easy-to-read format. And the news is not so good: About one-third of US birds are endangered, threatened, or are in significant decline. Here's why:Urban Sprawl, Habitat Loss Seen as Greatest Threat
The report singles out suburban sprawl and urbanization, as well as habitat loss due to other factors such as fragmentation of forests and conversion of grassland to agricultural purposes (including for use growing biofuel feedstocks) as being the prime threat to birds.
Unlike timber production and livestock grazing, urbanization and sprawl cause permanent loss of natural habitats. Increased development in rural areas, such as second-home development, has equal or greater ecological consequences than growth of urban centers.
Energy Production Also a Big Threat
Though separated out in its list of challenges facing bird conservation, the role energy production plays also falls under the category of habitat loss, degradation or fragmentation. Both development of conventional and alternative sources of energy were cited as negative influences on bird populations. Though no one form of energy development was singled out as being the worst, pver the past 40 years, many of the bird groups showing most rapid declines live in areas with the greatest potential for energy production.
Oil and gas development in the West is affecting birds such as the Greater Sage-Grouse by fragmenting large blocks of habitat. [...] Gulls that prey on other birds are subsidized by garbage dumps at drilling facilities in Alaska. [...] Collisions with wind turbines, offshore oil rigs, and powerlines cause significant mortality. Construction and operation of energy fields can displace birds and disrupt nesting. Prarie-chickens and sage-grouse avoid nesting near tall structures. Studies show that they usually abandon breeding areas near drilling rigs or wind turbines.
And then there is the effect of mining:
Mining can cause extensive habitat disturbance, degradation, and loss. For example, coal mining that blasts mountaintops to reveal coal seams below has removed large areas of eastern forests and buried nearby streamside habitats under tons of debris. This contributes to the decline of birds that breed in interior forests, such as Cerulean Warblers.
Wetland Conservation Programs Hailed
There were some optimistic findings in the report though: Over the past 40 years wetland birds have shown robust increases, largely due to the success of the wetlands conservation programs. Also, urban birds have shown large population increases, because as the Nature Conservancy so aptly puts it "we seem to create more and more habitat for them every day."
More: State of the Birds
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