Research Document - 2011/065
Results of narwhal (Monodon monoceros) aerial surveys in Admiralty Inlet, August 2010
By N.C. Asselin and P.R. Richard
Two aerial surveys were completed in August 2010 to assess the summering stock of narwhals in Admiralty Inlet. The surveys used an adaptive sampling plan which combined visual line-transect sampling of the entire inlet and aerial photography of aggregations of more than 50 animals. The two surveys yielded estimates of 24,398 (CV=0.25) and 13,729 (CV=0.40) narwhals. The differences between the two survey estimates are likely due to sampling variation related to survey coverage, sea state and animal movement. Combining the estimates from the two surveys using an effort weighted mean yielded a final Admiralty Inlet narwhal estimate of 18,049 (CV=0.23, 95% C.I.=11,613-28,053). This estimate was used to calculate a new recommended Total Allowable Landed Catch (TALC) for the Admiralty Inlet narwhal stock of 233 animals.
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