October 5, 2010 Featured Article Read More →

Irelands Smoothhounds

Condensed from an article on UnderwaterTimes.com

They grow to over a meter in length, can weigh up to twelve kilos and each summer they swarm into the shallow waters of the Irish east coast. Despite this, the starry smooth-hound has remained Ireland’s least well known shark species.

Dr. Edward Farrell, who recently graduated from UCD School of Biology & Environmental Science, spent the last four years studying these unusual sharks and investigating the age, growth, reproduction and identification of the species in the Northeast Atlantic.

"It’s amazing how little was known about this species considering their size and abundance on the east coast," said Farrell. "Until recently we weren’t even sure what species we were dealing with but we developed a genetic method which allowed us to confirm that it is the starry smooth-hound which occurs in Irish waters and not the related common smooth-hound. Once this was established we were able to investigate their life-history."

Starry smooth-hounds were previously considered to be a fast growing and early maturing species, meaning they were not a conservation concern. However the results of the four year project have revealed that starry smooth-hounds in Irish waters actually grow twice as slowly as previously estimated and only reproduce every two years rather than annually as is the case in the Mediterranean.

"Some of the findings are quite worrying for the species as males don’t mature until they are 4-5 years old and females until they are 6 years old, said Farrell. "Females also appear to take two years to complete the reproductive cycle. The pups develop inside the female for approximately 12 months before being born after which the female has a resting period of about another year before she is capable of becoming pregnant again."

Starry smooth-hounds are not a valuable commercial species in Ireland but on the continent they are highly sought after and the landings from French boats, currently about 2640 tonnes annually, are increasing. The previous lack of knowledge of their basic life history in the Northeast Atlantic has prevented the development of management and conservation strategies.

Once abundant in the Mediterranean Sea and Southern European waters, years of over fishing have caused their disappearance from much of their former range. In Irish waters though, starry smooth-hounds seem to be increasing in abundance. The reasons for this are unclear but it does offer the unique opportunity to help conserve this enigmatic species.

These findings of the project indicate that starry smooth-hounds are more susceptible to exploitation than previously thought and management measures are needed now to ensure their conservation.

Posted in: Shark Bites
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