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Generous funds provided by National Parks and Wildlife Service (of the Department of Environment, Heritage and Local Government Ireland) and the Marine Institute (Ireland), have enabled the continued success of this Swansea/Cork collaboration. The Coastal and Marine Resources Centre provided logistical support. The Sea Mammal Research Unit designed and built the incredible Satellite Relay Data Loggers (sat tags) used to track our turtles.
Unravelling the secret lives of jellyfish using electronic tags We now know that jellyfish the Irish Sea are not just passive drifters but appear to live in distinctly different areas, some close to the shore and others far out to sea. Perhaps the best example of this is the barrel jellyfish (Rhizostoma octopus) that forms enormous ‘blooms’ in large bays throughout the Irish Sea but is only rarely seen away from the coast. These blooms seem to occur for many months at a time and in the same spots year after year suggesting they play an important, yet poorly understood role in coastal ecosystems. One this we do know however, is that barrel jellyfish are an important food item for wandering leatherback turtles that visit the Irish sea each year, so it is important that we understand the reasons why jellyfish species are distributed the way they are.  To help answer this question we will attach tiny dive computers (smaller than your little finger), to barrel jellyfish in Carmarthen Bay, Tremadoc Bay (Wales) and Rosslare (Ireland) during summer 2008. This will tell us how jellyfish move up and down in the water column during the tidal cycle to avoid being washed out to sea, and the lifespan of each individual we tag. We attach the devices around the stalk (or penduncle) of the jellyfish, using simple cable ties and small float. When the jellyfish dies, the dive computer will float to the surface and wash ashore. Each device has a return address on it, so all you need to do is pop it in the post and we will send you a reward for your time and effort. Loggerhead Turtles wash up on Irish coasts During the past month, four loggerhead turtles have washed up along Irish coasts from Wexford to Kerry. These turtles are more typical of warmer waters and only occur in Irish waters when they stray off course. It is likely that they may have originated from Florida, America. Two specimens have been taken to Coastal and Marine Resources Centre (stored at the National Maritime College), University College Cork, where a necropsy (post mortem for animals) will be conducted to establish their age, sex and their exact origin. During this same period, two loggerhead turtles were found in Scotland, and a rare Kemp’s Ridley turtle was found in Wales, thus making it an exceptional month for stranded turtles in Ireland and the UK. 
Gubby and Christine Williams from Hare Island who found the loggerhead turtle last week Loggerhead turtles are not normally found in Irish waters, because water temperatures here are far too cold for their survival. Instead, adult loggerheads prefer the warmers waters of the Mediterranean, the Caribbean and North America’s east coast. The four turtles that were found have probably originated from the North American population of loggerheads. However it will require genetic analysis to confirm this assumption. It is thought that after leaving their nesting beach as hatchlings (when they measure 4.5 cm in length), these tiny turtles enter the North Atlantic Gyre (a giant circular ocean current) that takes them from America, across to Europe (Azores area), down towards North Africa, before being transported back again to America via a different current. This remarkable round trip may take many years during which these tiny turtles grow by several centimetres a year. Loggerheads may circulate around the North Atlantic several times before they settle in the coastal waters of Florida or the Caribbean. These four turtles were probably on their way around the Atlantic when they strayed a bit too far north from the Gulf Stream. Once they did, their fate was sealed, as the cooler waters of the North East Atlantic are too cold for loggerheads (unlike leatherback turtles which have many anatomical and physiological adaptations to enable them to swim in our seas). Once in cool waters, the body of a loggerhead begins to shut down as they get ‘cold stunned’, then get hypothermia and die. However, sometimes they can wash up alive! Therefore, if found, NEVER put a loggerhead turtle back into the sea as this will surely kill it! Instead, place the turtle in a dry, sheltered place until animal welfare experts can collect them for rehabilitation. Contact any of the aquariums (e.g. Dingle Oceanworld Aquarium and Lahinch Seaworld) or Dr Tom Doyle of the Coastal and Marine Resources Centre (UCC, see contact details below). With a stranding as recent as last week, it is likely that that some more may wash up, so keep your eyes peeled for loggerhead sea turtles. Turtle findings published in Endangered Species Research We are glad to announce that our efforts to satellite tag turtles off Ireland has paid off, with some important findings now published in the scientific journal Endangered Species Research. You can get access to this journal article by following the link here. Then scroll down until you find the article called “Leatherback turtles satellite-tagged in European waters” by Doyle, Houghton, O’Súilleabháin, Hobson, Marnell, Davenport and Hays. These first tracking results for leatherbacks in Europe support to the suggestion that the Bay of Biscay region within the Northeast Atlantic is a high-use area where some leatherbacks may spend several months presumably feeding on abundant jellyfish. We have also documented the movements of two turtles for up to a year, showing that both use the west coast of Africa when heading south, and that male turtles seen swimming in Irish/UK waters can return to their breeding grounds in French Guiana/Surinam in time for breeding. Establishing such knowledge is important, especially for endangered species where knowledge of their range and movements may be critical in helping to define important areas where conservation measures need to be implemented. JELLYFISH THRIVING IN OUR COASTAL SEAS Please click on the below link and learn how jellyfish, once considered unimportant, are now known to play a large role in the dynamics and healthy functioning of our coastal seas! This article was published in Inshore Island Magazine.
LEATHERBACKS HAVE ARRIVED! The first leatherbacks of 2007 have been sighted in early June (see figure). Jane Cotter of the Irish Whale & Dolphin Group reported the first sighting on the 4th June. The turtle was just inside the Mouth of the Shannon Estuary east of Loop Head, Co. Clare. Nic Slocum of Whale Watch West Cork spotted the second turtle the following day (5th June). This turtle was swimming towards land and came within 2 m of his boat! Amazingly, these turtles have come from the Caribbean or West African waters (e.g. Cape Verde area) during the last few months. They come up here to feed on our abundant supply of jellyfish.
April Update Bad news. We have not received any uplinks from our male turtle in 6 weeks. He was located ~700 km from the major nesting beach of Yalimapo Beach, French Guiana when transmissions ceased. At a later date we will provide a summary of his remarkable journey and achievements, but for now if you want to keep track of some leatherback movements check out this website: www.greatturtlerace.com -------------------------------------------------------- The Search for Ireland's Giant Turtles A new BBC 2 programme about our attempts to satellite track a leatherback sea turtle off the Dingle peninsula will be broadcast on Sunday 18th February at 5:50 - 6:20 pm! The real stars of the programme are the salmon fishermen Jimmy Flannery and Pádraig Frank O'Súilleabháin. Click here for more information about this programme -------------------------------------------------------- From Ireland to Brazil in 220 days! After ~220 days our male turtle is rapidly approaching the continent of South America (see red track on map). It's hard to believe that this is the same turtle that we first saw off the Dingle peninsula in Ireland on the 30th June 2006 (during the filming 'The Search for Ireland's Giant Turtles'). In quite an amazing journey, he left Irish waters in early July 2006 and headed due south for 10 days before residing in an eddy system west of the Bay of Biscay. He spent over two and half months in this rotating water body feeding on gelatinous plankton (e.g. jellyfish, salps, pyrosomes).Then in late September, he began heading south again and within a few weeks was approaching the island of Madeira. Keeping Africa to his left he then swam past the Canaries (in November) before arriving at Cape Verde in December. He slowed down when he arrived off Cape Verde and spent the next month gradually moving in a southwest direction (see red track on map). Then during the last few weeks he has picked up speed and travelled towards the Brazilian coastline. It is likely that he is heading towards the large nesting beaches located in French Guiana and Surinam to mate.
-------------------------------------------------------- Male turtle dives to 1280 metres! During December our male turtle dived deeper than any turtle ever recorded! He dived to an incredible depth of 1280 metres which is almost as deep as Ben Nevis is high (1344m)! An incredible feat, but as we mentioned before, we are still uncertain why leatherback turtles dive to such a depth. -------------------------------------------------------- The Story of Cuas If you remember Cuas (the first leatherback tagged off Ireland in 2005), she swam from Ireland to Cape Verde in a similar manner (see blue track on map), until she passed the Canary Islands where she turned towards the African coast and passed within 200 km of Mauritania. After looping south around Cape Verde she headed north towards Canada in March 2006. Unfortunately we lost track of Cuas as she approached Newfoundland in July 2006. At that point we had tracked her progress for close to a year! Where she is now we don't know, but there is every chance that she too is not far from the nesting beaches in South America. -------------------------------------------------------- See Footage Of Tagged Leatherback Turtle! Movie taken by Aoife Ni Súilleabháin of a tagged leatherback turtle -------------------------------------------------------- New Publications Check out our new publications on jellyfish, sunfish, and leatherbacks! -------------------------------------------------------- :: back to top ::
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