They hunt at night, have the gift of silent flight and look like a flash of white as they move, swoop and dive for their prey. Add to that a scream that probably sounds like a people’s idea of a banshee, who in Gaelic folklore was the spirit that wailed and foretold death in a household.
So misunderstood, these owls.
“Banding provides valuable information on life span, home range, nest site fidelity and migratory patterns, and assists in estimating population size,” he said.
The population is stable in Delaware, but in some states, these owls are listed as state endangered species. That makes them a species of concern, Lehman said. The state started building and placing nest boxes in Delaware in 1990.
The birds don’t have an easy time of it. As many as 75 percent die in their first year of life, and many don’t make it much beyond their first breeding season. They fall victim to predators, such as foxes, the larger great-horned owl and even raccoons. Loss of habitat from filling of marshes and destruction of old, abandoned or little-used building has also taken a toll, he said.
The largest populations of barn owls in Delaware are centered along the wetlands of the Delaware Bayshore. There, they feed on meadow voles.
At a nesting box in the state’s Woodland Beach Wildlife Area, it’s easy to see why they are such voracious eaters. There are seven pre-fledglings in this box.
Since 1996, biologists here have banded 556 barn owls.
Among this group are young birds from 117 broods and 29 adult females. Delaware’s birds are sometimes recaptured in New Jersey. One bird was recaptured at Blackwater National Wildlife Refuge near Cambridge, Md.
Because the birds in Delaware are so dependent on meadow voles, weather can play a key role in the success or failure of a brood. If the spring is dry, meadow voles stop breeding, and the food source for barn owls dries up, he said.
“That’s the disadvantage of keying in on one-prey species,” he said.
Once these predatory birds take flight, they’ll stop using the nest and will roost in trees during the day. By night, they’ll go hunting, scaring up a meal.
And maybe a few more ghost stories.
More pictures of last years banding -http://www.wildlifesouth.com/Featured/2011/Barn_Owl.html