Abundance of narwhals (Monodon monoceros) on the hunting grounds in Greenland

• DOI: 10.1644/09-mamm-a-198.1
• Publication Date: 2010-10-15T16:10:33Z
• Authors: M. P. Heide-JØrge...; K. L. Laidre; M. L. Burt; D. L. Borchers; T. A. Marques; R. G. Hansen; M. Rasmussen; S. Fossette
• Keywords: Aerial Survey; Distance sampling

Narwhals (Monodon monoceros L.) occur in the Atlantic sector of Arctic where for centuries they have been subject to subsistence hunting by Inuit Greenland and Canada. Scientific advice on sustainable levels removals from narwhal populations provides basis quotas implemented both The scientific relies heavily extensive aerial surveys that are only feasible way acquire data densities abundance throughout their range. In some areas lack information abundance, combination with high exploitation levels, has caused conservation concerns leading restrictions international trade tusks. also regarded as highly sensitive habitat disturbance global warming. This study analyzed sighting covering four major grounds Greenland. were conducted double observer experiments 2 independent observation platforms, 1 at front rear survey plane. using mark–recapture distance sampling techniques allow correction whales missed observers. corrected animals submerged during passage plane, diving submergence satellite-linked time–depth recorders deployed free-ranging narwhals. narwhals wintering ground West 2006 was 7,819 (95% confidence interval [CI]: 4,358–14,029). abundances Inglefield Bredning Melville Bay, northwest 2007 8,368 CI: 5,209–13,442) 6,024 1,403–25,860), respectively. East 2008 6,444 2,505–16,575). These provide first estimates important larger more complete previously surveyed Bredning. can be used setting catch limits harvest a baseline examining effects climate change abundance.