Snowy Owls Having Trouble MigratingBy: Ellisha Rader Mannering - April 13, 2014
It is time for many bird species to begin their spring migrations and Snowy Owls are among the many species that migrate. Although most birds migrate without any trouble it seems that more and more snowy owls are being found dead along their migration paths. While most ornithologists believe the recently reported Snowy Owls deaths are not related and only accidents, many are still studying the dead birds to be sure.
When a Snowy Owl wearing a GPS tracking device was found dead near Martha’s Vineyard, many people became concerned and wanted to know why this bird and so many others were dying. Tufts University veterinary center and Norman Smith, who is an expert on Snowy Owls, decided to find out what caused the bird’s death. They named the bird Sandy Neck.
The team examined the bird and released a report with their findings. The report said,
“The necropsy at Tufts showed no trauma except for a minor deep bruise in her left pectoral, no food in the proventriculus (stomach) or gizzard, and no signs of disease or unusual parasites. As Gus (Ben David) noted, she was in otherwise excellent condition – great muscle mass and fat deposits. Nor was there any water in the respiratory system. Mark Pokras (a veterinarian and professor at Tufts) said if he had to guess, she got swamped, swam to shore and went down from hypothermia – but also couldn’t rule out drowning.”
“Interestingly, the tracking data shows she was hunkered down for many hours Friday afternoon along the beach between Sengekontacket Pond and the ocean, then around 5 a.m. Saturday headed north over the bay. It looks like by 5:40 a.m. she was in the water, and I assume the movement after that – south a bit, up and around the top of the Island and then back – reflects tide and current, not the owl. So she might not have drowned, but simply died of hypothermia in the water. Looks like she came ashore about 8:30 p.m. on Saturday.” And was found the next day,” said Smith.
In many states, the cold is lingering longer than usual and although there have been several warm spells in the last few weeks, it could still be dangerous for migratory birds to make long flights. If they get caught in cold weather during their migration, they may not know what to do to survive sudden cold spells. Smith and other experts believe this could be the reason so many Snowy Owls are dying during their migrations this year.
What do you think could be the cause?
Image via Wikimedia Commons