Climate changeis affecting bird migration: due to the rise in average global temperatures, birds are arriving at breeding grounds too soon, causing some to miss out on food and space. Research carried out by the University of Edinburgh, which looked about a hundreds of species across five continents, found that birds are reaching their summer breeding grounds on average about one day earlier per degree of increasing global temperature.
It might seem a detail but the time they reach their summer breeding grounds is significant, because arriving at the wrong time, even by a few days, may cause them to miss out on vital resources such as food and nesting places. This in turn affects the timing of offspring hatching and their chances of survival. The research included species that travel huge distances, such as the swallow that can cover 200 miles a day at speeds of 17-22 miles per hour and pied flycatcher, a bird slightly smaller than a house sparrow, as well as those with shorter migrations, such as the lapwing and pied wagtail, which take flight because of changing seasonal temperatures and food availability.
The University of Edinburgh researchers examined records of migrating bird species dating back almost 300 years. They drew upon records from amateur enthusiasts and scientists, including notes from 19th-century American naturalist Henry David Thoreau. Apparently, among all species observed, long-distance migrants are the least responsive to rising temperatures, that is why they tend to arrive at breeding grounds late and have, therefore, fewer resources available. Scottish scientists hope their study, published in the Journal of Animal Ecologyand supported by the British Natural Environment Research Council, will help predict how different species will respond to future environmental changes caused by global warming.