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USGS · 5222744

Captive and field-tested radio attachments for bald eagles

D.A. Buehler·J.D. Fraser·M.R. Fuller·L.S. McAllister·J.K.D. Seegar
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Abstract

The effects of two radio transmitter attachment techniques on captive and one attachment technique on wild Bald Eagles (Haliaeetus leucocephalus) were studied. A Y-attachment method with a 160-g dummy transmitter was less apt to cause tissue damage on captive birds than an X-attachment method, and loosely fit transmitters caused less damage than tightly fit transmitters Annual survival of wild birds fitted with 65-g transmitters via an X attachment was estimated at 90-95%. As a result of high survival, only five wild birds marked as nestlings were recovered.Two of these birds had superficial pressure sores from tight-fitting harnesses It is recommended that a 1.3-cm space be left between the transmitter and the bird's b ack when radio-tagging post-fiedging Bald Eagles. Additional space, perhaps up to 2.5 cm, is required for nestlings to allow for added growth and development.

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D.A. Buehler, J.D. Fraser, M.R. Fuller, L.S. McAllister, J.K.D. Seegar. 1995. Captive and field-tested radio attachments for bald eagles. https://pubs.usgs.gov/publication/5222744

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