Increasing Mist Net Captures of Migrant Northern Saw-whet Owls with an Audiolure

Brinker, David; Erdman, Thomas

Abstract--In 1986, an "Audiolure" was developed and tested at the Little Suamico Ornithological Station. The Audiolure consisted of broadcast amplified "solicitation" calls of Northern Saw-whet Owls normally associated with courtship activities. From 1971 through 1985, using passive mist netting at Little Suamico, the mean number of owls captured each autumn was 57. Using an audiolure, from 1987 through 1995 the mean annual catch was 636 owls. During 1989, an Audiolure was also tested at Finzel Swamp in western Maryland bycomparing captures during adjacent 3-hour time blocks. Use of an Audiolure significantly increased capture rates over passive mist netting. Audiolures are now being used by all major Northern Saw-whet Owl banding stations in the western Great Lakes area to net 2,000-3,000 owls each autumn. Audiolures have also proven effective for netting saw-whet owls during both the breeding and wintering seasons. Descriptions of the audiolure and basic characteristics of captures at simple autumn migration netting operations are also presented.