Pup production and population growth of hooded seals (Cystophora cristata) near Newfoundland, Canada

• Published in: Canadian Journal of Fisheries and Aquatic Sciences
• Main Authors: Stenson, G.B., Myers, R.A., Ni,I-H, Warren, W.G.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 1997
• Subjects: Canada; Cystophora cristata; hooded seal; Newfoundland
• Online Access: http://repository.ust.hk/ir/Record/1783.1-16923; https://doi.org/10.1139/cjfas-54-s1-209; http://lbdiscover.ust.hk/uresolver?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rfr_id=info:sid/HKUST:SPI&rft.genre=article&rft.issn=0706-652X&rft.volume=54&rft.issue=Suppl. 1&rft.date=1997&rft.spage=209&rft.epage=216&rft.aulast=Stenson&rft.aufirst=G.+B.&rft.atitle=Pup+production+and+population+growth+of+hooded+seals+(Cystophora+cristata)+near+Newfoundland,+Canada; http://gateway.isiknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=LinksAMR&SrcApp=PARTNER_APP&DestLinkType=FullRecord&DestApp=WOS&KeyUT=000207611500025; http://www.scopus.com/record/display.url?eid=2-s2.0-0030617743&origin=inward

Pup production of hooded seals (Cystophora cristata) in two whelping concentrations along the northeast coast of Newfoundland (the "Front") during March 1990 was estimated using systematic visual surveys. In addition, independent estimates of production in one of the concentrations and the number of pups born outside the whelping concentrations were obtained from photographic surveys. Photographic estimates were adjusted for incorrectly identified pups by comparing black and white photographs with ultraviolet imagery. Estimates were also corrected for pups that had yet to be born at the time of the survey or had left the ice using distinct age-related developmental stages. Approximately 91\% of the pups born in the first whelping concentration, and 92\% born in the second, were present during the surveys. Based on a combination of visual and photographic surveys, the corrected pup production in these concentrations was estimated to be 49 600 (SE = 2700). Photographic surveys resulted in an estimate of 33 500 (SE = 12 400) pups born outside the whelping patches, although this estimate could not be corrected for the abscence of pups due to the temporal distribution of births. Thus, total pup production was estimated to be 83 100 (SE = 12 700). Although nominally greater, this estimate is not statistically different from a comparable estimate of hooded seal pup production in 1984.