@article{b3520ddb7ad148679af2f167f7932d6b,
title = "An investigation of avoidance by Antarctic krill of RRS James Clark Ross using the Autosub-2 autonomous underwater vehicle",
abstract = "The autonomous underwater vehicle (AUV) Autosub-2 was deployed on eight missions ahead of RRS James Clark Ross in the northern Weddell Sea and in the Bransfield Strait, Southern Ocean, to assess avoidance of the research vessel by Antarctic krill Euphausia superba. The AUV was equipped with the same type of scientific echosounder as the research vessel (Simrad EK500 operating at 38 and 120 kHz) and measured the density of krill along transect acoustically (g m-2 wet mass) prior to the ship's arrival. We hypothesised that if krill avoided the ship, perhaps in response to radiated noise, then the ship should detect less krill than the AUV which is known to have much lower noise levels than the ship. We were unable to detect any significant difference between the density of krill detected by the ship or the AUV, either at the transect level or at finer scales within transects. We conclude, therefore, that avoidance by krill of RRS James Clark Ross will not significantly bias acoustic estimates of krill abundance by this vessel.",
keywords = "Acoustic survey, Antarctic krill, Autosub, Avoidance, Biomass estimate, Euphausia superba, Vessel noise",
author = "Brierley, {Andrew S.} and Fernandes, {Paul G.} and Brandon, {Mark A.} and Frederick Armstrong and Millard, {Nicholas W.} and McPhail, {Steven D.} and Peter Stevenson and Miles Pebody and James Perrett and Mark Squires and Bone, {Douglas G.} and Gwyn Griffiths",
note = "Funding Information: We are indebted to the Master, Officers and crew of RRS JCR cruise 58 for their enthusiasm and seamanship skills that enabled Autosub-2 to be deployed and recovered successfully on all occasions, often in testing conditions. Our thanks go to Rachel Woodd-Walker (British Antarctic Survey) and Mary Robjant (British Oceanographic Data Centre) for their assistance with net sampling and to Mark Preston, Pete Lens and Chris Drew (British Antarctic Survey) for computing and electronic support at sea. Duncan McGehee (BAE Systems) kindly provided code enabling us to explore his krill TS model, Rob Fryer (Fisheries Research Services) provided invaluable advice on statistical analyses, and Ron Mitson (Acoustec) provided advice on noise comparisons. Two anonymous referees provided comments that improved the clarity of the paper. This work was supported by Grant Number GST022151 awarded by the UK{\textquoteright}s Natural Environment Research Council to ASB, MAB and PGF under the Autosub Science Missions Thematic Programme. ",
year = "2003",
month = feb,
doi = "10.1016/S0165-7836(02)00144-3",
language = "English",
volume = "60",
pages = "569--576",
journal = "Fisheries Research",
issn = "0165-7836",
publisher = "Elsevier",
number = "2-3",
}