Effects of radiotransmitters on the reproductive performance of Cassin's auklets
We examined whether radiotransmitters adversely affected the reproductive performance of Cassin's auklets (Ptychoramphus aleuticus) breeding on the California Channel Islands during 1999-2001. We attached external radiotransmitters to 1 partner in 108 Cassin's auklet pairs after nest initiation and used 131 unmarked, but handled, pairs as controls. Compared to alpha chicks raised by radiomarked pairs, alpha chicks raised by unmarked pairs had faster mass growth rates (1.95 ± 0.30 g d−1 vs. 3.37 ± 0.53 g d−1, respectively), faster wing growth rates (2.46 ± 0.10 mm d−1 vs. 2.85 ± 0.05 mm d−1), greater peak fledging masses (118.9 ± 3.5 g vs. 148.3 ± 2.4 g), and higher fledging success (61% vs. 90%). Fledging success was reduced more when we radiomarked the male (50% fledged) rather than the female partner (77% fledged). After fledging an alpha chick, unmarked pairs were more likely to initiate a second clutch (radiomarked: 7%; unmarked: 39%) but did not hatch a second egg (radiomarked: 4%; unmarked: 25%) or fledge a second (beta) chick (radiomarked: 4%; unmarked: 18%) significantly more often than radiomarked pairs. We resighted 12 radiomarked individuals nesting during a subsequent breeding season; each bird had shed its transmitter and healed the site of attachment. We suggest caution in using telemetry to evaluate the reproductive performance of alcids, but marking only females may minimize adverse effects.
Citation Information
Publication Year | 2004 |
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Title | Effects of radiotransmitters on the reproductive performance of Cassin's auklets |
DOI | 10.2193/0091-7648(2004)032[1229:EOROTR]2.0.CO;2 |
Authors | Joshua T. Ackerman, Josh Adams, John Y. Takekawa, Harry R. Carter, Darrell L. Whitworth, Scott H. Newman, Richard T. Golightly, Dennis L. Orthmeyer |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Wildlife Society Bulletin |
Index ID | 70026281 |
Record Source | USGS Publications Warehouse |
USGS Organization | Western Ecological Research Center |