Many recent sightings
Wild dolphins have been making their presence felt in the North Sound recently.
In fact, according to the Department of Environment there have been more sightings of bottlenose dolphins there recently than there would normally be.
According to Timothy Austin, Deputy Director Research and Assessment with the Department of Environment, it’s difficult to confirm the number of animals present or how long they have been resident in Cayman waters, as there seems to have been at least several sightings of the same individual.
In July 2008, the DoE initiated a Marine Animal Sightings Database, asking members of the public to report sightings of dolphins, whales, manatees, sharks, manta rays, and other large marine animals.
‘We hope that this information will help us determine relative abundance, distribution, and migration patterns, as well as assess the importance of Cayman waters for these species,’ said Mr. Austin.
He said that since the database began, three sightings of pods of oceanic dolphins and seven sightings of bottlenose dolphins have been reported.
In fact, there have been more sightings of bottlenose dolphins because members of the public often mentioned seeing the same dolphin several times but couldn’t recall details of previous sightings and therefore made one report to the database.
Janice Blumenthal, research officer at the Department of Environment explained that there is really no baseline as dolphin sightings in the North Sound have only been reported to the database since October 2008.
However, she said that, anecdotally, bottlenose dolphins are not permanently resident in Grand Cayman, so in that sense, there have been more sightings than normal recently. However, in the past there have been occasional visiting animals that have spent a short time here – so it’s not unusual that this seems to have happened again.
Mr. Austin explained that there are usually no coastal dolphins normally resident in the waters around Cayman possibly because Cayman’s coastal shelf area is so small.
Asked if the wild dolphins could have been attracted by the Dolphin Cove captive dolphins at Morgan’s Harbour in West Bay, or whether they could be related to the animals in captivity, Mr. Austin said they are not sure.
More Information Needed
‘To answer these questions, it is clear that more information is needed on the natural presence of dolphins (and other marine mammals) in Cayman,’ he said.
Ms Blumenthal said that from the North Sound they received several reports of single dolphins and one report of four to five bottlenose dolphins seen together.
Back in February the Caymanian Compass reported that a lone dolphin was hanging around the Dolphin Cove swim-with-dolphin facility and seemingly communicating with the captive dolphins there. Also around this time there was a sighting of a couple of other dolphins.
Director of Zoological Operations with Dolphin Cove Philip Admire said that they have not seen any wild dolphins around their dolphin facility recently. And the lone dolphin has not been seen by them in a few months, he said.
But he added that boat captains have reported seeing them in the area every now and then.
‘For all I know he is still coming to the gate in the middle of the night and we don’t see him, but we have not observed any dolphins here.’
Asked if he believed it was possible that the lone wild dolphin they had seen outside the Dolphin Cove facility earlier in the year could have come from the original pod of ‘Cuban’ dolphins the Dolphin Cove dolphins are from, Mr. Admire said, ‘I find it highly unlikely that a lone dolphin would come all that way on its own. They are shallow water creatures and don’t tend to cross ocean channels. They are coastal mammals.
‘In my 20 years experience working with these animals I find that very hard to believe and the odds of that happening would be astronomical.’
Asked the same question, Senior Scientist with the Humane Society International Naomi Rose said that while it is possible that the dolphins seen off the southern coast of Cuba make their way seasonally to the Cayman Islands, there is absolutely no reason to assume that.
She said that most coastal bottlenose dolphins are residents to some home range and do not cross major channels (such as the stretch of water between the Cayman Islands and Cuba). ‘These channels which are often deeper than coastal waters, usually act as natural geographic or oceanic barriers to dolphins.’
However, she said that there are always exceptions to rules and the proximity and density of islands in the Caribbean mean that the hypothesis that bottlenose dolphins move from island to island is plausible.
‘Not enough research on Caribbean dolphins has been done to clarify how they move about in their home ranges or how big their home ranges are.’
She said that photo ID and/or genetic studies would need to be done to find out whether dolphins seen in the Cayman Islands are the same animals as those in Cuba.
However, she said the lone dolphin that was seen earlier this year may not have been alone as other dolphins were spotted around that time.
‘They are fission-fusion species, meaning they come together and move apart all the time. Some individuals will find themselves ‘alone’ occasionally but they are actually rarely far from other dolphins – they are almost always in acoustic contact, even if they can’t see each other.’
She said that ‘lone sociable’ dolphins usually are healthy and appear to have separated from a pod voluntarily. ‘They are considered ‘sociable’ because they tend to approach and interact with people or boats while on their own. If they are treated with respect (not harassed or teased and if boats do not crowd or feed them), they can survive for months of years in this way. Eventually most ‘disappear’ (which may mean they have died or that they have returned to their pod of origin.’
Campaigner with the local group Keep Dolphins Free in the Cayman Islands Billy Adam emphasised the need for legislation in order to protect species such as dolphins.
‘Since the early 1990s the Cayman Islands has been talking about passing a national conservation law and to date it can’t get done. The environment is key to our tourism industry.’
He said that the wild dolphins’ presence in the North Sound would go towards proving the assertion that there is no such thing as ‘Cuban’ dolphins because they travel vast distances. In reality the dolphins are the property of no country or island, the Dolphin Cove dolphins were only caught in Cuban waters not that they are ‘Cuban’ dolphins.
‘This shows once again the reason for international treaties such as the UN Special Protected Areas and Wildlife Protocol covering wide geographical areas to protect the natural world from the devastating damage man causes.’
The Department of Environment has recently received Overseas Territories Environment Programme funding for a project with the Save Our Seas Foundation that intends to establish baseline surveys for marine mammals in the area. This is planned for November to December of this year.
The public can report marine mammal sightings to the DoE marine mammal database by calling 949-8469 or by e-mailing [email protected]. Photos of sightings would also be welcomed.