Authors: Wang, John Y.; Yang, Shih Chu; Fruet, Pedro F.; Daura-Jorge, Fabio G.; Secchi, Eduardo R.

Source: Bulletin of Marine Science, Volume 88, Number 4, October 2012 , pp. 885-902(18)

Publisher: University of Miami - Rosenstiel School of Marine and Atmospheric Science

Abstract:

Accurate and precise estimates of abundance and survival rates are important for assessing the conservation status of cetacean populations. Mark-recapture analysis of photo-identification data of the critically endangered eastern Taiwan Strait (ETS) population of Indo-Pacific humpback dolphin, Sousa chinensis (Osbeck, 1765), was conducted on data collected between 2007 and 2010 to refine a preliminary, and the only available, abundance estimate for this isolated population (n = 99; CV = 51.6%), as well as to provide survival rates. About 14,000 good quality photographs (about 2100-6300 yr^-1) were used to estimate both parameters for marked animals under Pollock's Robust Design model. The total population size (N_T) was determined by correcting for the proportion of the population possessing long-lasting marks (θ). The annual point estimates were lower, varying from 54 to 74, and had much better precision (CV varied from 4% to 13%) than previous estimates, suggesting that mark-recapture is a suitable method for estimating abundance of this population. These estimates also further supported the precarious state of the ETS population under another criterion of the IUCN Red List of Threatened Species. As expected for long-lived mammals, annual apparent survival rate was high at 0.985 (95% CI = 0.832-0.998). Continuing to monitor the ETS population of humpback dolphins with such high precision and accuracy will allow examination of the population's trends over time and to better understand its future persistence.

Document Type: Research article

DOI: http://dx.doi.org/10.5343/bms.2010.1097

Publication date: 2012-10-01

More about this publication?

• The Bulletin of Marine Science is dedicated to the dissemination of high quality research from the world's oceans. All aspects of marine science are treated by the Bulletin of Marine Science, including papers in marine biology, biological oceanography, fisheries, marine affairs, applied marine physics, marine geology and geophysics, marine and atmospheric chemistry, and meteorology and physical oceanography.
• Editorial Board
• Information for Authors
• Subscribe to this Title
• Terms & Conditions
• ingentaconnect is not responsible for the content or availability of external websites

Related content

• In this: publication
• By this: publisher
• In this Subject: Biology/Life Sciences ,  Oceanography
• By this author: Wang, John Y. ;  Yang, Shih Chu ;  Fruet, Pedro F. ;  Daura-Jorge, Fabio G. ;  Secchi, Eduardo R.

Website © Publishing Technology. Article copyright remains with the publisher, society or author(s) as specified within the article.

• Terms and conditions
• Privacy policy
• Information for advertisers