[MARMAM] New publication on cetacean numbers and trends around Iceland
kinguq at gmail.com
Mon Jun 8 12:06:16 PDT 2020
We are pleased to announce the publication of our paper:
Distribution and abundance of cetaceans in Icelandic waters over 30 years
of aerial surveys.
The paper is available here:
Pike, D. G., Gunnlaugsson, T., Sigurjónsson, J., & Víkingsson, G. A.
(2020). Distribution and Abundance of Cetaceans in Icelandic Waters over 30
Aerial Surveys. NAMMCO Scientific Publications 11.
Beginning in 1986, 7 aerial surveys covering the coastal waters of Iceland
have been conducted up to and including 2016. In addition, 7 partial
surveys covering portions of the same area and at different times of the
year have been flown in the same 30-year period. We present previously
unpublished abundance estimates, corrected to the extent feasible for known
biases, for common minke whales (*Balaenoptera acutorostrata*), humpback
whales (*Megaptera novaeangliae*), white-beaked dolphins (*Lagenorhynchus
albirostris*) and harbour porpoises (*Phocoena phocoena*) from some or all
of the 2007, 2009 and 2016 surveys. We also examine the distribution of
these and other species in Icelandic waters over the 30-year timespan of
the surveys, and changes observed over the period. The relative abundance
of common minke and humpback whales and white-beaked dolphins was
comparatively low in the spring and fall, and peaked in June and July when
all of the main surveys have been carried out. An analysis of changes in
density as an index of relative abundance from all surveys (1986-2016)
indicates that common minke whale abundance decreased by up to 75% after
2001 and has remained at a relatively low level since then. This decrease
has been particularly apparent in the southwest and southeast of Iceland,
areas which previously had very high densities. Relative abundance of
humpback whales and white-beaked dolphins has increased over the period
1986-2016, particularly in the northern part of the survey area. Estimating
harbour porpoise abundance and trend was considered unfeasible except from
the surveys conducted in 2007 and 2016, which provide abundance estimates
of similar magnitude. We place these observed changes in context of
oceanographic and ecosystem changes documented over the same period.
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the MARMAM