Every time Snowy Owls flip up in winter within the decrease 48 states and southern Canada, they mild up social media and rare-bird alerts and could also be reported on in newspapers or by native broadcasters. The birds could keep in a single place for some time, as one well-documented younger Snowy did this winter in New York Metropolis’s Central Park, or they could transfer round. Rather a lot.
A paper printed in March within the journal Ornithology tracked the actions of fifty Snowies that had been tagged with GPS transmitters in japanese and central North America from 2013 to 2019 as a part of Undertaking SNOWstorm, a analysis effort that research the species.
The researchers, led by Rebecca McCabe of McGill College, categorized 58 % of the owls as nomadic and 42 % as “range-resident,” that means they remained in an space of about 19 sq. kilometers. Nomadic owls wintered in areas protecting greater than 200 sq. kilometers.
A hen’s social standing as a consequence of age, intercourse, or physique mass didn’t play a task in whether or not it stayed put for the winter, the researchers reported. As a substitute, the deciding issue on whether or not a hen roamed or not was habitat. Owls in cropland areas tended to remain in a single space, probably as a result of these areas have loads of prey. Birds close to water or wetlands tended to maneuver round.
“The Atlantic and Nice Lakes coasts symbolize lengthy, linear habitats with few geographic obstacles corresponding to mountain ranges,” writes McCabe. “An owl transferring alongside a shoreline encounters an virtually endlessly unspooling practice of habitat which facilitates lengthy, linear actions seeking meals because the water freezes over domestically or patchy waterfowl flocks transfer.”
McCabe and colleagues additionally word that “totally different conservation methods could also be warranted” for range-resident and nomadic owls. They usually say the survival charges of the 2 wintering teams warrant additional examine.