Sea ice habitat characteristics and number of narwhal (Monodon monoceros) sightings in Disko Bay, West Greenland ...

There is a paucity of information on abundance, densities, and habitat selection of narwhals Monodon monoceros in the offshore pack ice of Baffin Bay, West Greenland, despite the critical importance of winter foraging regions and considerable sea ice declines in the past decades. We conducted a doub...

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Bibliographic Details
Main Authors: Laidre, Kristin L, Heide-Jørgensen, Mads Peter
Format: Article in Journal/Newspaper
Language:English
Published: PANGAEA 2011
Subjects:
IPY
Online Access:https://dx.doi.org/10.1594/pangaea.815150
https://doi.pangaea.de/10.1594/PANGAEA.815150
Description
Summary:There is a paucity of information on abundance, densities, and habitat selection of narwhals Monodon monoceros in the offshore pack ice of Baffin Bay, West Greenland, despite the critical importance of winter foraging regions and considerable sea ice declines in the past decades. We conducted a double-platform visual aerial survey over a narwhal wintering ground to obtain pack ice densities and develop the first fully corrected abundance estimate using point conditional mark-recapture distance sampling. Continuous video recording and digital images taken along the trackline allowed for in situ quantification of winter narwhal habitat and for the estimation of fine-scale narwhal habitat selection and habitat-specific sighting probabilities. Abundance at the surface was estimated at 3484 (coefficient of variation [CV] = 0.46) including whales missed by observers. The fully corrected abundance of narwhals was 18 044 (CV = 0.46), or approximately one-quarter of the entire Baffin Bay population. The narwhal ... : Data extracted in the frame of a joint ICSTI/PANGAEA IPY effort, see http://doi.pangaea.de/10.1594/PANGAEA.150150 ...