Contact: Joanna Wilson, DNREC Public Affairs, 302-739-9902.
Signs of spring on state wildlife areas: Wildlife staff bands screech owls, cleans nest boxes
DOVER (Feb. 21, 2012) – This month, to prepare for the spring bird breeding season, more than 350 nesting boxes at state wildlife areas throughout Delaware are getting their annual spring cleaning by DNREC Division of Fish and Wildlife staff. Perched high on predator-proof poles at heights from six to 30 feet above the ground or water in forested wetlands, these boxes are designed primarily for wood ducks, but also can provide perfect nesting and roosting places for screech owls.
Screech owls are tiny red or gray raptors, about the size of the adult human hand. These nocturnal creatures feed on small mammals, insects, birds, amphibians such as frogs, and sometimes fish. The owls seldom build their own nests, preferring instead to adopt woodpecker holes, natural cavities in large trees or manufactured nesting boxes. Nest predators include raccoons, cats, great horned owls and arboreal black rat snakes. Human activities also can interfere with their nesting cycle.
Eastern screech owls prefer forests and treelines that provide both nesting cavities and adjacent foraging habitat – usually open areas where mice and other small rodents live. Typically, these owls also prefer areas with cover such as a moderately dense shrub layer to provide foraging perches and roosting habitat when not using cavities.
Although there are nesting boxes designed specifically for screech owls, they may use the same type of nest boxes as wood ducks. The two species also can use separate wood duck boxes in the same area, if the boxes are placed in or near appropriate habitat. However, wood ducks face competition and eviction from the boxes by a non-native invasive species: European starlings, though this can be minimized through proper box placement.
“Starlings are aggressive in taking over suitable nesting cavities and preventing native species from using them. However, placement of the nesting boxes can tip the scales in favor of the native species,” said Kent County Regional Wildlife Manager Wayne Lehman, DNREC Division of Fish and Wildlife. “Starlings prefer to nest in open habitat, whereas both screech owls and wood ducks like nesting in wooded areas. We’ve placed the nesting boxes shared by screech owls and wood ducks primarily in wooded habitat, where the boxes don’t attract starlings.”
“For more than 20 years, we have been helping to provide screech owls with safe nesting and roosting areas. Throughout the year, we encourage the public not to open the boxes because owls will abandon nests if disturbed by humans,” Lehman continued. “The annual winter cleaning also provides us with the opportunity to band the owls and record important data that’s used to help assess the overall health of the species.”
The banding of screech owls was initiated in 1993 to provide DNREC’s scientists with information on the owls’ life span, home range, habitat preferences, nest box fidelity and migration patterns. The banding serves as a key research tool to access impacts to the species caused by the loss of their natural habitat through increases in land development.
DNREC’s conservation efforts to protect screech owls is one of several initiatives of Delaware’s Natural Heritage and Endangered Species Program, as well as Delaware’s Wildlife Action Plan, which outlines a comprehensive strategy for conserving the full array of native wildlife and habitats in the state.
Plastic wood duck boxes are available to the public for purchase for $30 through the Division of Fish and Wildlife’s regional wildlife offices in each county. For more information in New Castle County, call 302-834-8433; in Kent County, call 302-284-1077; or in Sussex County, call 302-539-3160.
For more information on banding screech owls and barn owls, contact Wayne Lehman, Division of Fish and Wildlife, at 302-284-1077.
Vol. 42, No. 53