Military Tag 20 Sharks In The Eastern Pacific
Sixteen military personnel representing the Army, Navy and RAF have just returned from an ambitious diving expedition to tag endangered sharks around several remote Pacific islands off the west of coast of Mexico. The expedition travelled from Guadalupe to the Revillagigedo Islands from 19 Oct – 07 Nov 2008.
The expedition, called EXERCISE JURASSIC SHARK 2, was the second shark tagging expedition to be conducted by the Joint Services Shark Tagging Team. The aim was to contribute to shark conservation around Guadalupe and the Revillagigedo Islands in the Eastern Pacific by tagging a total of 20 sharks. The expedition set out to tag great white and scalloped hammerhead sharks in order to gather information on their movements. The tags send signals to underwater radio receivers allowing the movements of the sharks to be recorded.
All tagging was carried out whilst the sharks were free swimming as this is the least stressful method for the animal. The expedition started at Guadalupe, west of the Baja California where 10 great white sharks were tagged from the surface under the direction of a locally-based scientist. Sharks were also observed from a cage from where the team photographed a large female shark never before seen at Guadalupe. The team now have the responsibility of naming this shark on the database of great white sharks found around the island (now 86 individuals).
Four days were spent tagging great whites before the team headed south to the Revillagigedo Islands, a largely uninhabited group of volcanic islands to the south of the Baja California peninsula, where they begun the far from easy task of tagging scalloped hammerheads sharks; an exceptionally skittish species. All diving from here onwards was carried out in open water in areas that should have been prime shark habitats. Tragically, the effects of shark fishing meant that hardly any sharks were seen until the team reached an isolated rock outcrop just 80 metres long called Roca Partida. Four man dive teams dived three times per day on a rotational basis in order to optimise the use of the spear guns used for tagging. Strong currents, huge swell, sheer rock walls, extreme depths and the presence of sea urchins made this a difficult site from which to tag sharks. Nevertheless, 6 hammerhead sharks, 3 Galapagos sharks and a silver-tip shark were eventually tagged. Tissue samples were also taken from 2 manta rays for DNA and toxin analysis.
The research work carried out by the expedition took place in co-operation with two Mexican marine research organisations: The Centro De Investigaciones Biologicas del Noroeste, S.C. (CiB), Mexico and the Centro Interdisciplinario de Ciencias Marinas (CICIMAR). The expedition was sponsored by the Joint Services Expedition Trust and approved by the Royal Geographical Society. The scientific equipment was purchased with funds from Selex Galileo.
The expedition was led by Major Andy Reid (Army), who explained, “An expedition such as this is all about experiencing controlled exposure to risk with the aim of developing the kind of leadership, teamwork, courage and co-operation that is vital to military operational capability. The expedition also assisted with two important conservation projects, both of which exploit the skills of a Joint Services team to best effect. Sharks are in dramatic decline around the world and this is our chance to make a difference by establishing those parts of the shark’s habitat that most need protection.”
Corporal Tim Gort (Army), another member of the expedition said, “The expedition has been hugely ambitious and an incredible experience. The rate that sharks are being needlessly killed is unsustainable and most are now endangered. The work we have done will result in a better understanding of shark movements and help in the development of national and international strategies for their protection.”
Overall, the expedition succeeded in tagging 20 sharks with radio tags and placed 4 radio receivers. Tissue samples were also taken from great whites and manta rays. Capt Richard Beck (Army) tagged a great white and said, “It is not every day that you are able to tag a 5 metre great white shark; this expedition really brought home to you the value and beauty of sharks.”
The team hope to build on the success of Jurassic Shark 2 with another expedition in summer 2010.
Further information can be found on the expedition website at http://www.jurassic-shark.org.uk