Harry has returned from Isla Vieques. Since almost two years we have been investigating the shark nurseries of this Puerto Rican island. What started as a challenging endeavour from a logistical point of view (lack of water and fuel, strong winds and heavy thunderstorms, availability of gear, problems with boats and cars to name just a few ...) is now well on track to become a rewarding project.
With a new 1,000 foot gillnet, Harry was able to sample Ensenada Honda in a very efficient way. With refined methods and the help of local volunteers he caught 86 juvenile sharks and re-caught 11 tagged during a previous survey, all with zero mortality. Remarkably and noteworthy this time he caught only blacktip sharks (Carcharhinus limbatus) with one exception: a blacknose shark (Carcharhinus acronotus). Different to previous surveys no lemon sharks (Negaprion brevirostris) and Caribbean sharpnose sharks (Rhizoprionodon porosus) were encounterd. About 90% of the sharks caught were newborns. The recapture rate of about 15% is encouraging for our future work in the bay.
A next field trip to Vieques is planned for end of this year and we will soon start deploying a receiver array and equip sharks with acoustic transmitters.