Monday, March 15, 2010
Climate Change to Blame for Bird Decline
(Deforestation Photo: The Argentimes.com)
Two recent articles discuss the effects of climate change on birds. One article talks of climate change affecting the body size of birds, while the other speaks of climate change altering habitat and food supplies of birds.
According to a BBC Earth News article, a study of almost half a million birds, belonging to over 100 species, shows that many are gradually becoming lighter and growing shorter wings. This shrinkage has occurred within just half a century, with the birds thought to be evolving into a smaller size in response to warmer temperatures.
Dr Josh Van Buskirk of the University of Zurich, Switzerland and colleagues Mr Robert Mulvihill and Mr Robert Leberman of the Carnegie Museum of Natural History in Rector, Pennsylvania, US decided to evaluate the sizes of hundreds of thousands of birds that pass through the Carnegie Museum's Powdermill ringing station, also in Pennsylvania.
Of 83 species caught during spring migration, 60 have become smaller over the 46 year study period, weighing less and having shorter wings. Of the 75 species migrating in autumn, 66 have become smaller. In summer, 51 of 65 breeding species have similarly reduced in size, as have 20 out of 26 wintering species. "The headline finding is that the body sizes of many species of North American birds, mostly songbirds, are gradually becoming smaller," says Dr Buskirk. This suggests that bird species in North America are obeying Berman's rule, by evolving into a smaller size as temperatures increase.
According to an article on AFP.com, US Interior Secretary Ken Salazar warned that climate change is pushing some bird species "towards extinction," as a new report on the threats facing North American birds was released. Birds that depend upon the ocean for survival "are among the most vulnerable birds on Earth to climate change," warned the report put together by the US Fish and Wildlife Service in coordination with several environmental groups. These species of birds have been producing few offspring each year and their habitats are most susceptible to climate change phenomena.
In mountainous and Arctic regions "increased temperatures will drastically alter surface water and vegetation," meaning species like the White-tailed Ptarmigan and rosy-finches "may disappear... as alpine tundra diminishes."
"Birds are excellent indicators of the health of our environment, and right now they are telling us an important story about climate change," said Kenneth Rosenberg, director of conservation science at Cornell University's Lab of Ornithology, a contributor to the report. "Many species of conservation concern will face heightened threats, giving us an increased sense of urgency to protect and conserve vital bird habitat," he added.
Time after time, we see reports like these that are predicting our world’s future and telling us to take care of our planet. Whether it is the decline in bird populations, tiger populations, or some other species’ population, the cause for their decline and threatened status is from habitat loss and encroachment from humans.
ACR and cat rescues across the US, across the world, want conservationists to STOP scapegoating cats as a way of deflecting attention away from the human impacts on wildlife degradation. Along with habitat destruction, pesticides, pollution, radio towers, and (Photo: Don Northup-IllinoisPhoto.com)window and airplane collisions are main causes for the decline of bird populations, not cat predation. According to an article by the Council on Hemispheric Affairs, “experts estimate that each minute, 11 football fields of forest are cleared. With all the environmental and ecological consequences, one must question the motives of not only the Brazilian government [referring to clearing the Amazon], which has tolerated such a destructive development model, but also its endorsement by the international community which has jeopardized the future of mankind.” Migrating birds depend on these rainforests year after year, and as they decline, so do the birds; not to mention, deforestation contributes to climate change, which the above articles have shown to affect bird populations. Conservations admit that they are not saying cats are the number one cause of bird deaths, but they also say that it is too late to find solutions or at least try to slow down human impacts, that it is easier to kill cats…so let us take that approach. Using cats as scapegoats is very dangerous, for it fosters cruelty to animals and the time spent placing blame is only time wasted. Blaming cats and practicing “catch and kill” is OUT-DATED, UNNECESSARY, and INHUMANE.