MALLORY, M.L. & GILBERT, C.D. 2008. Leg-loop harness design for attaching external transmitters to seabirds. Marine Ornithology 36: 183–188.

Many techniques have been used to attach telemetry equipment to wild birds for both short-term (single-season) and long-term (multipleseason) studies. Most attachment techniques designed for long-term retention of transmitters by seabirds have used a backpack style chest harness. This approach may cause discomfort and irritation under the wing. We describe a new leg-loop harness technique that we employed with mixed success on two polar-nesting seabirds: South Polar Skuas Catharacta maccormicki and Northern Fulmars Fulmarus glacialis.The appropriateness of this or any harness package is species-specific, and we experienced differing results—the leg-loop harness performed

satisfactorily with skuas, but nest abandonment and probable adult mortality were the rule in fulmars. We believe the leg-loop design offers a suitable alternative to chest harnesses for some species and telemetry applications.

Key words: Northern Fulmar, Fulmarus glacialis, South Polar Skua, Catharacta maccormicki, transmitter attachment, harness design, behavioral effects, reproduction, survival