- Title
- Factors affecting recapture rates of raggedtooth sharks Carcharias taurus tagged off the east coast of South Africa
- Creator
- Dicken, Matthew L, Booth, Anthony J, Smale, Malcolm J
- Date
- 2010
- Type
- text
- Type
- article
- Identifier
- http://hdl.handle.net/10962/124493
- Identifier
- vital:35618
- Identifier
- https://doi.10.2989/AJMS.2009.31.3.9.997
- Description
- Understanding differences in the recapture rate between different tags (A-, B- and C-types), capture methods (rock-and-surf anglers, scientific divers and Natal Sharks Board protection nets) and life-history stages (juvenile and adult) is critical in evaluating the results obtained from cooperative tagging programmes (CTPs). A generalised linear modelling approach, using a log-linear model, was used to determine significant differences in the probability of recapture between these various factors using data from the Oceanographic Research Institute and Port Elizabeth Museum CTPs. Between 1984 and 2004, a total of 3 385 raggedtooth sharks Carcharias taurus was tagged by volunteers from both programmes along the east coast of South Africa. A likelihood ratio test indicated significant differences in the probability of recapture between A- and C-type and B- and C-type tags (p < 0.01), between different capture methods (p < 0.05) and between juvenile and adult sharks (p < 0.01). A comparison of recapture rates between members of the CTPs also indicated a marked variability in the performance of individual taggers. The study highlights important data-quality issues inherent in large CTPs.
- Format
- 9 pages, pdf
- Language
- English
- Relation
- African Journal of Marine Science, Dicken, M.L., Booth, A.J. and Smale, M.J., 2009. Factors affecting recapture rates of raggedtooth sharks Carcharias taurus tagged off the east coast of South Africa. African Journal of Marine Science, 31(3), pp.365-372, African Journal of Marine Science volume 31 number 3 365 372 2010 1814-232X
- Rights
- African Journal of Marine Science
- Rights
- Use of this resource is governed by the terms and conditions of the Taylor & Francis Online Terms and Conditions Statement (https://www.tandfonline.com/terms-and-conditions)
- Hits: 1847
- Visitors: 1984
- Downloads: 159
Thumbnail | File | Description | Size | Format | |||
---|---|---|---|---|---|---|---|
View Details Download | SOURCE1 | Factors affecting recapture rates of raggedtooth sharks Carcharias taurus tagged off the east coast of South Africa.pdf | 383 KB | Adobe Acrobat PDF | View Details Download |