Ragnar transmitter to provide rare insight about seal movement
EXCITING new marine research may be the result of a rare visitor to the SA coastline.
This as Ragnar the crabeater seal, which was rescued from Ramsgate beach just over a week ago, is expected to be released back into the ocean early next week with a satellite transmitter attached to it.
This species of seal is normally found around the Antarctic and although abundant in the ocean, has hardly ever been seen along the South African coast.
Saambr vet and curator of animal health at uShaka Sea World, Dr Francois Lampen, who is caring for the seal, said: “Historically these seals have only been found three or four times along our coastline in the last 40 years. When they were found here, there was normally a pair or more. Around the same time this seal was found in Ramsgate, a second seal was also found in East London and is being looked after at Bayworld Aquarium in Port Elizabeth. Both the seals are males.”
He said the crabeater seal is earless, unlike the seals commonly seen off the South African coastline known as fur seals and which have ears. The crabeater seal does not “walk” with its flippers, but rather weaves back and forth.
The staff at uShaka Sea World named the visiting seal Ragnar, after the famous Viking Ragnar Lothbrok, as the plucky seal also comes from the icy wastes and has travelled the world.
Lampen said the seal was in good health and, after being flown down to Bayworld in Port Elizabeth, blood samples and X-rays would be taken and a full health assessment would be done, before a satellite transmitter is attached. Both seals will be taken out to sea on a boat and released back into the ocean.
He said they had been working closely with Dr Greg Hofmeyr from Bayworld, who has considerable experience in marine mammal management. Why the two seals arrived on our coastline was still being investigated.
Lampen said while previous research had been done on these seals through attached transmitters, this had been done from the Antarctic and not from the African mainland.
“We hope the seals will head south. The main interest is to track their movement,” said Lampen, adding that a number of other research factors would also be monitored, for example how deep the seals dive, how fast they move and the environment such as temperature of the ocean.
The transmitter will remain in place until the seal moults his coat and the transmitter’s battery runs out. The crabeater is known to have a “catastrophic moult” which is a drastic shedding of its coat.
Lampen also highlighted that the name crabeater was a misnomer, because Antarctic krill makes up 90% of the crabeater seal’s diet. They have special teeth to filter the seawater and catch the krill. The remaining 10% of their diet is squid and fish which was Ragnar’s staple diet while being fed at uShaka.
“When he sheds his coat, the transmitter will fall off, but until then we expect to gather a huge amount of information on a crabeater seal in a sub-Antarctic region and we do feel it’s important to the conservation and research for this wild population, so we can shed light on what is taking place,” said Lampen.