North Atlantic humpback whale abundance and rate of increase four decades after protection from whaling

Stevick, Peter T. and Allen, Judith and Clapham, Phillip J. and Lien, John (2003) North Atlantic humpback whale abundance and rate of increase four decades after protection from whaling. Marine Ecology Progress Series, 258. pp. 263-273. ISSN 1616-1599

[img] [English] PDF (Migrated (PDF/A Conversion) from original format: (application/pdf)) - Published Version
Available under License Creative Commons Attribution Non-commercial.

Download (787kB)


Humpback whales Megaptera novaeangliae in the North Atlantic Ocean were severely depleted by exploitation. With legal protection since 1955, substantial recovery is likely to have occurred, but information on abundance and rates of increase has been limited. We present an assessment of humpback whale abundance in the North Atlantic Ocean based upon capture-recapture estimates using naturally marked individuals. These data result from a long-term collaborative effort combining large-scale dedicated projects and incidental data collection, leading to extensive geographical coverage. The application of robust statistical techniques produces estimates of greater accuracy and precision than has previously been possible. Abundance estimates ranging from 5930 to 12 580 individuals, with coefficients of variation (CVs) from 0.07 to 0.39, were calculated for the West Indies breeding population using data from 1979 to 1993. The most precise estimate for the West Indies breeding population is 10 752 (CV = 0.068) for 1992 and 1993. Due to application of new analytical methods, these estimates are larger and more precise than those previously published from similar time periods. The average rate of increase for the West Indies breeding population over a 14 yr period was estimated to be 0.031 (SE = 0.005). The best available estimate for the entire North Atlantic population of humpback whales is 11 570 (95 % CI 10 290 to 13 390) based upon samples from 1992 and 1993. However, this estimate may be biased downwards to an unknown extent due to heterogeneity in capture probabilities that do not influence the West Indies estimates.

Item Type: Article
Item ID: 538
Additional Information: * et al.: Peter T. Stevick1, Judith Allen, Phillip J. Clapham, Nancy Friday, Steven K. Katona, Finn Larsen, Jon Lien, David K. Mattila, Per J. Palsbø, Jóhann Sigurjónsson, Tim D. Smith, Nils Øien, Philip S. Hammond
Keywords: Abundance estimation; Capture-recapture; Humpback whale; Population increase
Department(s): Science, Faculty of > Ocean Sciences
Date: 29 August 2003
Date Type: Publication

Actions (login required)

View Item View Item


Downloads per month over the past year

View more statistics