Title of article :
Current status of hooded seals in the Greenland Sea. Victims of climate change and predation?
Author/Authors :
طigهrd، نويسنده , , Tor Arne and Haug، نويسنده , , Tore and Nilssen، نويسنده , , Kjell Tormod، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2014
Pages :
8
From page :
29
To page :
36
Abstract :
Hooded seals (Cystophora cristata) have been harvested for centuries in the North Atlantic. Estimating abundance and monitoring changes in population size are critical for the management of the species. In March 2012, the hooded seal pup production was estimated from aerial photographic surveys over the Greenland Sea whelping areas. From this survey the total pup production estimate was 13,655 (s.e. = 1900, CV = 13.9%). The status of the hooded seal population in the Greenland Sea was assessed by fitting a population model to independent pup production estimates, historical catch data, and reproductive data. The 2013 total abundance (including pups) was estimated to be 84,020 (95% c.i. 68,060–99,980) hooded seals. This is well below the management reference level N30 in the established precautionary harvest strategy for hooded seals in the North Atlantic developed by ICES, and a consequence of this is that no catches should be take from this population. The model predicts a decreasing population size of about 7% over the next 10 years, assuming no hunt. Currently there is a very modest hunt for scientific purposes. Predictions including this hunt indicate an 8% decrease of the population over the next 10 years. Possible reasons, including climate change and predation, for this negative trend are discussed.
Keywords :
Abundance estimation , Age-structured population model , aerial photos , MANAGEMENT , Hooded seals , Pup production
Journal title :
Biological Conservation
Serial Year :
2014
Journal title :
Biological Conservation
Record number :
1914758
Link To Document :
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