Smooth Sailing Success for OCEARCH in Gansbaai

April 16, 2012 by dyertrust

First Hand Insights on the South African Collaborative Shark Study

great white sharkOn Thursday the 12th of April, the vessel OCEARCH began the second leg of their white shark research expedition in the area of Gansbaai. Over the course of two days the team managed to successfully attract in and satellite tag 8 individual great white sharks in the area ranging in size from 2.5m to over 4.55m total length.

The Dyer Island Conservation Trust's marine biologists Oliver Jewell and Alison Towner went on board the vessel. "I have to say I am thoroughly impressed with the whole operation of the OCEARCH crew," says Jewell. "The two days I've spent onboard have been two of the best of my career and the way in which the sharks were handled was world class. The sharks were efficiently brought aboard the platform and the tagging and releasing process took an average of 12 minutes. All the sharks swam away healthily and one even circled the boat a couple of times before moving off on her way. It's so important that this area was sampled and we've already learnt so much; the sharks were bigger than we thought and we now know we have sexually mature males in the area. The satellite tags from the larger sharks will transmit for up to 5 years and for the first time we will know where these sharks go when they leave our coastline, discover new foraging areas and possibly even, where they are mating and pupping. Furthermore we've collected blood, genetic, stable isotope, parasite and bacterial samples which are going to researchers across the country on what really is a nationwide study."

There had been some concern over difficulties working in an area in which eight operators are running cage diving expeditions, however good communication between those onboard OCEARCH and the commercial operators ensured things ran smoothly with sharks being sampled at Dyer Island during the morning and then the more active inshore areas in the afternoon once cage diving trips were finished. There was speculation as to how much bait and chum OCEARCH had on board and we can confirm they used only sardine and tuna, approximately 35kg a day.

Wilfred Chivell, chairman of the Dyer Island Conservation Trust (DICT) www.dict.org.za and CEO of Marine Dynamics Shark Tours (www.sharkwatchsa.com) is a passionate conservationist who has supported and sponsored shark research in Gansbaai for over a decade. "Gansbaai is a very important area for the Great White shark and I am happy that this area has been included in the project," says Chivell. "Our biologists are each taking part in this research, in fact, it has brought all South African shark researchers together, as one united team. To generate enough funding for expensive research is not easy and this is the perfect platform to allow us to understand the great white shark better. Im also happy that the government have helped to accommodate such a project."

"The data Chris Fischer and his team are making possible is unprecedented," says Towner. As an observer on the vessel I was able to stand back, away from the cameras, and watch the whole operation. I can only complement the team on how well they worked together and handled the sharks. They are clearly experienced and know what they are doing. Now four of the tagged sharks are already transmitting data, three of which are still within the Greater Dyer Island area."

All tracking data collected from sharks tagged in the Gansbaai area will be collected by the Dyer Island Conservation Trust for analysis and used for their biologists PhDs. Other data collected from the sharks will be utilised by researchers across the country, as part of a national study.

Andy Stephany a shark conservationist living in Kleinbaai commented: "It's been such a mystery since Nicole was tagged and swam to Australia and back. Why she did it and if others have done it since has been a mystery until now. Ten years on and finally we will be able to get some long waited answers to these questions. It is a very good thing to have and I will be sitting on eggshells waiting for the results to come in. There's always something new we can find out and now we will - it's absolutely fantastic!"

Kleinbaai's Harbour Master reports, "From our side we can say that everything went really well, the OCEARCH team were professional and no conflict occurred between them and other vessels in the area".

About Dyer Island:
Dyer Island is a 20ha Nature Reserve, situated 8.5 Km from Kleinbaai harbour in Gansbaai. It is the easternmost, of the chain of seabird islands of the Western Cape. Dyer Island is managed by Cape Nature, primarily for seabirds and shore birds. Some of the birds breeding on the island include the vulnerable African Penguins and endangered Bank Cormorant and Roseate Tern. The island is recognized as an Important Bird Area (IBA), which gives Dyer Island the same status as an IBA anywhere else in the world. There are 1228 IBAs in Africa, and 101 in South Africa. Thus, from a national bird conservation perspective, Dyer Island is one of the hundred most important sites in the country.

Contact:
Dyer Island Conservation Trust: info@dict.org.za