Diving depths of northern gannets: acoustic observations of Sula bassana from an autonomous underwater vehicle
Brierley, Andrew S.; Fernandes, Paul G.. 2001 Diving depths of northern gannets: acoustic observations of Sula bassana from an autonomous underwater vehicle. Auk, 118 (2). 529-534. 10.1642/0004-8038(2001)118[0529:DDONGA]2.0.CO;2Full text not available from this repository. (Request a copy)
The Autonomous Underwater Vehicle (AUV) Autosub-1 made observations of the sea surface with an upward-looking echosounder during fish surveys in the vicinity of Shetland and Orkney (North Sea) in July 1999. Echograms from the AUV contained vertical traces extending downwards from the sea surface that were caused by diving seabirds. Visual observations provided evidence that those seabirds were Northern Gannets Sula bassana. Analysis of trace extent suggests a mean dive depth of 19.7 m (n = 19, SD = 7.5). Data on gannet diving depths are sparse, but this value is somewhat deeper than that accepted for the related Cape Gannet (Morus capensis, mean 5.9 m) which has been used in foraging models for the Northern Gannet. These observations have implications for our understanding of the foraging capabilities of gannets, and the interactions of gannets with commercially targeted fish species.
|Item Type:||Publication - Article|
|Digital Object Identifier (DOI):||10.1642/0004-8038(2001)118[0529:DDONGA]2.0.CO;2|
|Programmes:||BAS Programmes > Antarctic Science in the Global Context (2000-2005) > Dynamics and Management of Ocean Ecosystems|
|Date made live:||26 Jun 2012 13:16|
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