Migratory birds may soon find their long travel ventures getting a bit longer. While several species of birds travel astonishingly far distances, new studies indicate that a warming planet will present new challenges to snow birds.
At the Cornell Laboratory of Ornithology, Dr. Frank La Sorta and his colleagues published a study demonstrating the effects of climate extremes on migrating birds. For example, extreme climate changes increase energy costs to birds that will have to fly farther, chasing a never-ending spring. An increase in travel distance can tax an already fatigued and tired bird increasing mortality rates and, because some birds leave at specific times to migrate, birds may end up in layover areas where former food resources are now scarce. The study indicated that populations of migratory birds that fly long distances are at an ever-increasing disadvantage. Short-term migrants appeared to be more resistant because they are already traveling in specific areas and can better manage available resources.
David Yarnold, president and CEO of the National Audubon Society, reports in an interview with NPR, “It’s a little bit like going to a new place where you’re not sure if there’ll be water or power; do you think you’ll be able to survive there?” And he makes a good point. Extreme weather affects things like foraging and breeding grounds–not to mention the fledging of young birds. It’s easy to see the potential impact this can have on population outcomes. Migration in birds evolved over thousands of years and some bird species are not able to adapt and keep pace with swiftly moving climate change.
Current events in the news show that weather patterns altered by climate change can have deadly consequences for some species. An article , just published in the New York Times, reports a mass mortality event off Long Island, New York beaches where hundreds of dead seabirds washed ashore. Joe Okoniewski, a wildlife pathologist with the New York Department of Conservation, performed necropsies of the birds who were found to have starved to death. Mr. Okoniewski commented, “The birds are extremely thin and anemic”. While it remains a mystery as to why the birds where so thin and light weight, scientists suspect they were blown off course by climate change altered weather conditions while flying over the open ocean.
Under the present climate conditions, with projections towards a warming planet, many species of birds could see their current breeding and migratory ranges decrease and food resources disappear. Given that the mid-latitude areas of the Northern Hemisphere boasts the majority of the world’s bird species that migrate, it is important to understand the role that climate change plays in bird migration and develop plans to help mitigate loss. In addition, certain species may no longer be able to breed and nest in certain states, leaving those particular species with different climate futures, and others grounded.
Nicole Reggia, Director http://www.nowthatswild.com