We shouldn’t hound out Irish sharks

THE Smooth-hound shark may be in danger of being wiped out here.

I find sharks fascinating and rather beautiful creatures and, to judge by the amount of documentaries about them on television, so do a lot of other people. Most of the attention focuses on large shark species found in tropical waters. We don’t hear so much about the ones that swim off our own coast and, in fact, not a lot is known about them.

But Dr Edward Farrell of UCD, along with two other marine biologists, Dr Stefano Mariani and Dr Maurice Clarke, has been studying them for the past four years and the results of this work have just been published. They make interesting reading.

They focussed on a fish called the smooth-hound. It’s not a particularly large shark, although it can grow to over a metre in length and weigh 10 or 12 kilos. Many people wouldn’t even call it a shark, they’d use the rather pejorative term ‘dog-fish’. Whatever you call them, they’re fascinating and it appears they may be in some danger of being wiped out.

The first thing the researchers discovered was that the smooth-hounds round our coast are not common smooth-hounds, as everybody believed, but another species called the starry smooth-hound, which used to be associated with more southerly parts of the eastern Atlantic and with the Mediterranean. That shows just how little we knew about them.

The second myth they de-bunked was they were a fast-growing and early maturing species that were of no conservation concern. In fact males don’t mature until they’re four or five years old and females until they’re six. And these females carry their maturing young for a year before they give birth and then take a year off before becoming pregnant again.

A reproductive rate as slow as this makes them very vulnerable to over-fishing and because the east coast of Ireland appears to be a vital nursery ground for the species we have a special responsibility.

The fact that smooth-hounds still exist in relatively large numbers around our coast is largely due to the fact that historically we didn’t rate them highly as a food fish. But the marketing of fish is an increasingly globalised business and they are very much sought after in southern Europe. In fact they have been fished to extinction in many parts of the Mediterranean.

A closely related shark species, the spur-dog, suffered just such a fate in the 1980s. When I was a student, eking out my income by hauling lobster pots during the summer vacation, we hated spur-dogs. They were then the commonest shark species and frequently trapped in lobster pots. They have a spine in front of each of their dorsal fins and getting one out of a lobster pot without getting spiked was tricky. But a market was found for spur-dogs and now they have been virtually wiped and are listed as critically endangered on the International Union for Conservation of Nature redlist.

At present there are no quotas or conservation strategies for smooth-hounds. This is largely because, up until now, so little was known about them. If we ignore the new research and fail to save another of our shark species there could be many repercussions.

Smooth-hounds don’t eat fish. They specialise in preying on small crab species. If we remove this predator from the marine ecosystem there could be serious side-effects. Apart from this, its loss would be something no one could defend.

The zoological name for sharks, rays and skates is ‘elasmobranch’. To find out more about them log on to irishelasmobranchgroup.org

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