Link to Bermuda Sun article from Wednesday July 8th
Bermuda holds secrets to the elusive Eagle Ray
Wednesday, July 08, 2009
|Research: Scientist Matt Ajemian (right) is assisted in the weighing of the captured Eagle Ray which is seen below being netted in to the boat. *Photos by Sarah Lagan|
PHD student Matthew Ajemian is visiting Bermuda from the University of South Alabama seeking an insight into the ray's movements and behavioural patterns.
He is returning to complete the next phase of his research focusing on the ray's interaction with Bermuda's Calico Clam, now scarce here but once seen in their droves.
Harrington Sound has been tapped as an ideal location for researching the Eagle Ray as it is one of the only places in the world where their numbers are abundant. The theory is their population could be on the rise.
"Sharks are top predators and rays are just below them," explained Ajemian. "There is a thinking out there that because we have removed the top level from the ecosystem - with over-fishing we have fished out sharks - that this group is starting to really explode in population.
"A lot of these species have not been studied and we have very little understanding of their ecological role. That is disconcerting because a related species to the Eagle called the Cow Nosed ray has been blamed for destroying shellfish harbours all over the States - the Eastern Oyster in the Chesapeake Bay, the Bay Scallop down in North Carolina."
"We want to get a better handle of the ecological roles of these animals because no one's ever looked at them in Bermuda and there are very few studies around the world." Ajemian explains.
His method on this trip has been to set up enclosures for the clams and rays and record the clams' mortality rates - his prediction is that the majority of predation in this area is down to the rays.
In his final phase of research he will look at their migratory behaviour which still remains a mystery. Eagle Rays have been spotted off shore on Bermuda's seamounts but it's believed that they remain here all year round due to our temperate climes.
Ajemian said one reason Bermuda was chosen as a location is due to the efficiency of aquarium collector Chris Flook's methods of capturing the slippery species - notoriously difficult to catch.
I went along to see Flook in -action. After scouring the Sound we spotted one ray close to Trunk Island and gently pulled it in using a 'purse net'. The net, with floats up top and lead weights down below, encircles the ray and is gathered up on deck.
After a little struggle the ray was anaesthetized, weighed measured and photographed and released and a few of us jumped in the water to take some pictures.
In the water Ajemian came into fairly close contact with the ray and it appeared to jolt towards him as a warning but a gentle stroke of the belly calmed her. She glided around us for a little while before whooshing off into the distance. There was never a moment I felt threatened or uneasy by her behaviour but just in awe of her beauty and the grace of her movements.
While the ray is a creature feared by many for its deadly sting they are apparently shy of humans and therefore relatively unthreatening.