by Alison Mitchell, Co-Executive Director, New Jersey Conservation Foundation
Every year, New Jersey is visited by thousands of migrating owls.
From Eastern screech-owls to long-eared owls, a variety of strange sounds echo throughout forests around dawn and dusk. In fall, one particular TOOT-TOOT-TOOT whistle excites bird enthusiasts throughout the state: the sound of the Northern saw-whet owl.
Although Northern saw-whets are well-adapted to their surroundings in the boreal forests of Canada – feathered all the way to the foot and speckled with white flecks resembling light snowfall – females and younger males migrate south beginning in early October. They are the smallest owl in eastern North America and New Jersey’s smallest bird of prey, weighing no more than a stick of butter.
Why the risky journey? To stay fed during the winter, preferably by hunting mice, voles, shrews, and other fuzzy delicacies.
Unlike long-distance migration patterns of most birds – where the winter destination is a specific, far away location – owls are considered “irruptive” migrants. They are opportunistic, traveling only as far south as they need in order to survive the winter. Northern saw-whet owls may fly over a thousand miles, spanning all different human landscapes and natural areas.
Winter mortality for first-year travelers is high – close to 80% of young Northern saw-whets do not survive, in part due to the appetites of larger owls. New Jersey is home to eight owl species: Great horned, snowy, barred, barn, Eastern screech-owl, long-eared, short-eared, and Northern saw-whet. Unfortunately, smaller species like saw-whet and screech tend to make good snacks.
Migration irruptions vary from year to year, which is one of the reasons why researchers band the birds. Birds are fitted with lightweight, aluminum bracelets that are used to identify unique individuals and their behavioral patterns. From mid-October to the end of November, stations around New Jersey and the northeastern United States band Northern saw-whet owls and other birds to gather data and track populations.
“Owls that migrate live tragic and epic lives,” says Mike McGraw, senior wildlife biologist at Princeton Hydro and Ornithology teacher at the University of Pennsylvania. He has been banding owls for 15 years.
There is a passionate community of banders stationed around New Jersey, from the Cape May Raptor Banding Project to professionally-trained one-man-band birders, most of which are loosely affiliated with Project Owlnet. Founded in 1994, Project Owlnet facilitates communication, cooperation, and innovation among a rapidly growing network of owl-migration researchers in North America and abroad.
Tyler Christensen is another Northern saw-whet owl bander, and the research coordinator for the Wild Bird Research Group, a New Jersey-based nonprofit that partners with Mercer County and the Watershed Institute. “It’s a little early in the season – migration peaks around Halloween – but signs are really good.”
He says that double-digit Northern saw-whet owl counts across multiple nights in October are encouraging. But not all owls are doing well in this state we’re in.
Barn owls have grown increasingly rare since the 1980s, mostly due to agricultural chemicals, rat poison, and habitat loss. They are likely to be listed as threatened in the very near future. Barred owls are considered threatened in New Jersey but their populations have expanded over the last 40 years because our forests are maturing. Older trees are larger, offering more hollows as nesting sites for barred owls.
Currently, the state has virtually no regulations protecting our maturing, publicly-owned forests. The lack of strong protections for these forests leaves maturing barred owl habitats vulnerable to logging –sometimes for projects designed to encourage game species. That means the owl population increases observed could easily be reversed.
Owls need sustained access to the range of landscapes that New Jersey has to offer. Grassland-loving barn owls need wild, open, chemical-free fields. High-flying longed-eared owls need mature forest for breeding and dense groves of evergreens as communal winter roosts. “From the perspective of a long-eared owl, somebody’s yard that was just mowed is a mini desert,” Christensen says. “People can manage their yards as wildlife habitat to support all kinds of biodiversity. Partially-forested areas, shrubs, and other plants provide habitat – unlike a big open lawn.”
Winter is a good time for spotting owls, as leaves continue to fall and expose bare branches. If you can’t get out into the woods, visit The Raptor Trust in Millington or the Woodford Cedar Run Wildlife Refuge in Medford, both of which house injured owls that cannot otherwise survive.
“There is so much we do not know about birds – about owls,” McGraw says. “So much unfolds for the migrating saw-whet owls, which breed in the northern forest, raise young, and then leave in August or early September, sometimes just a few months old. It is a ridiculous lifestyle!”
For owls to thrive, we need to promote old growth forest development, regenerative agriculture that uses few or no chemical pesticides, and ban raptor-harming rodenticides. We have come a long way from centuries of clear cutting our forested landscape and treating our waterways as chemical disposal sites, but there are many new threats that we must confront if we want all species to thrive in this state we’re in!
For more information on owls and monitoring programs, visit www.wildbirdresearch.org. The Watershed Institute’s calendar of events at https://thewatershed.org/programs-events-page/ is a good place to check for in-person saw-whet banding opportunities, though they fill up quickly. The Cape May Raptor Banding Project’s demonstrations are in full swing, so visit www.capemayraptors.org to catch one of their presentations, which offer plenty of opportunity for questions and discussion and provide first-hand observations of magnificent birds.
To learn more about preserving New Jersey’s land and natural resources, visit the New Jersey Conservation Foundation website at www.njconservation.org or contact me at info@njconservation.org.
