Prop. 11.49 CONSIDERATION OF PROPOSALS FOR AMENDMENT OF APPENDICES I AND II Other proposals Executive summary

• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Cetorhinus maximus
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.646.3018; http://www.cites.org/sites/default/files/eng/cop/11/prop/49.pdf

· The Basking Shark (Cetorhinus maximus) is widely distributed in coastal waters and on the continental shelves of temperate zones in the northern and southern hemispheres. The species is planktivorous, bears a small number of live young (ovoviviparous) and is the second largest fish in the world (up to 10m in length and 5-7t in weight), exceeded only by the whale shark Rhincodon typus. · C. maximus is considered to be Vulnerable in the 1996 IUCN Red List based on past records of declining populations, due to over-exploitation by fisheries, slow recovery rates and the potential for similar declines to occur in future due to targeted and by-catch fisheries. · The biology of the species makes it especially vulnerable to exploitation: it has a slow growth rate, a long time to sexual maturity (c. 12-20 years), a long gestation period (1-3 years) and a similar interval between pregnancies, low fecundity (the only recorded litter was of just six very large pups), and probable small populations. However, the species is poorly studied and many aspects of its life history remain to be elucidated. Its habit of ‘basking ’ at the surface makes it vulnerable to harpoon fisheries. · There are a few well-documented fisheries for C. maximus (especially from the NE Atlantic) and these suggest stock reductions of 50-90 % over short periods (typically a few decades or less). These declines have persisted into the long-term with no apparent recovery several decades after exploitation has ceased.