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A retrospective evaluation of the Barents Sea capelin management advice

Published on Feb 7, 2015in Marine Biology Research1.291
· DOI :10.1080/17451000.2014.928414
Harald Gjøsæter25
Estimated H-index: 25
,
Bjarte Bogstad20
Estimated H-index: 20
+ 1 AuthorsSamuel Subbey1
Estimated H-index: 1
Abstract
AbstractSince 1998, the assessment model framework Bifrost/Captool has been used for advice on total allowable catch for the Barents Sea capelin (Mallotus villosus) stock. However, since the management is based on a target escapement strategy, and most capelin die after spawning, viewed in retrospect, there is hardly any possibility of checking whether the forecast underpinning the quota was actually realistic. The forecast using Captool for the period from 1 October up to capelin spawning time at 1 April relies on a forecast of cod abundance during this period. This estimate of cod abundance is, in turn, based on a cod assessment from the previous spring. By rerunning the Captool model, where the cod forecast is replaced with the actual amount of cod from the cod assessment model run later in time, we show that considerably smaller annual quotas would have been advised if the true amount of cod had been known when the capelin quota was set. We discuss this fact in light of the present knowledge about rec...
  • References (15)
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Abstract The avoidance reactions of Barents Sea capelin (Mallotus villosus) to Norwegian research vessels were studied by means of the Bergen Acoustic Buoy (BAB), which was equipped with a Simrad EK60 echo-sounder operating at a frequency of 38 kHz. BAB experiments were carried out in the capelin's feeding area in the Barents Sea in the autumn and on its spawning grounds in Varangerfjord in Northern Norway in early spring. The vessel approached the BAB at normal survey speed (approximately 11 kn...
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