Estimates of the abundance of cetaceans in the central North Atlantic based on the NASS Icelandic and Faroese shipboard surveys conducted in 2015

  • Daniel G. Pike Esox Associates
  • Thorvaldur Gunnlaugsson Marine and Freshwater Research Institute
  • Bjarni Mikkelsen Faroese Museum of Natural History
  • Sverrir D. Halldórsson Marine and Freshwater Research Institute
  • Gísli Víkingsson Marine and Freshwater Research Institute
Keywords: NASS, North Atlantic, cetaceans, abundance, surveys, Balaenoptera, physalus, musculus, borealis, acutorostrata, Megaptera, Physeter, Globicephala, Hyperoodon, Lagenorhynchus

Abstract

The North Atlantic Sightings Survey (NASS), the sixth in a series of surveys conducted between 1987 and 2015, was conducted in June/July 2015 and covered a large area of the northern North Atlantic. The Icelandic and Faroese ship survey component of the NASS covered the area between the Faroe Islands and East Greenland from latitude 52° to 72° N. The survey used 3 vessels and an independent double-platform configuration with each platform staffed by a minimum of 2 observers. Here we present both uncorrected abundance estimates derived using Multiple Covariates Distance Sampling, and corrected abundance estimates derived using Mark-Recapture Distance Sampling, for the following species: fin (Balaenoptera physalus), common minke (B. acutorstrata), humpback (Megaptera novaeangliae), blue (B. musculus), sei (B. borealis), sperm (Physeter macrocephalus), long-finned pilot (Globicephala melas) and northern bottlenose (Hyperoodon ampullatus) whales as well as white-beaked (Lagenorhynchus albirostris) and white-sided (L. acutus) dolphins. We then compare these estimates to those from previous NASS and put them into context with estimates from adjoining areas of the North Atlantic.

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Published
2019-09-16
How to Cite
PikeD. G., GunnlaugssonT., MikkelsenB., HalldórssonS. D., & VíkingssonG. (2019). Estimates of the abundance of cetaceans in the central North Atlantic based on the NASS Icelandic and Faroese shipboard surveys conducted in 2015. NAMMCO Scientific Publications, 11. https://doi.org/10.7557/3.4941