Smooth Talking
Have you ever caught or seen a Starry Smoothhound?. What about a Common Smoothhound?. If you reckon the answer to both of these questions is yes then read on, because you might want to change you mind. Currently, both names appear in the British, Scottish and Welsh record fish lists. Only the one inclusion however under the inclusive heading of Smoothhound appears in the Irish list and has done for quite some while for reasons that will become clear in due course. The Starry Smoothhound, scientific name Mustelus asterias, has as the name suggests, small white spots or 'stars' scattered over its upper flanks and back, whereas the Common Smoothhound Mustelus mustelus is plain grey all over. But as Irish comedian Jimmy Cricket would say, come here, there's more.
Unlike bony fish species such as Cod and Bass which are covered in scales, sharks and rays instead have what are known as dermal denticles. These are tiny sharp edged out-growths covering the skins entire outer surface which when rubbed against the grain from tail to head are what gives them their dry rough feel. To a trained eye using magnification, the dermal denticles of the two smoothhound species reputedly differ sufficiently in their patterning and ridges to allow positive identification, a fact which unfortunately ain't going to help us as anglers one iota. A second equally un-helpful positive identifying feature, in part because it is only of use with female fish, but more importantly because it is a destructive technique requiring 'invasive surgery' and would therefore be abhorrent to most sea anglers, is the fact that any pups developing inside a Starry Smoothhound will have no physical maternal connection to the mother, whereas those of the Common Smoothhound do. But why am I going to all the trouble of telling you this when, as everyone knows, smoothhounds caught with white spots are Starries and those without spots are Commons - aren't they?.
Well, based on recent and ongoing scientific research, it would appear that the simple answer to that last question is a very definite and resounding NO. So much so that fish recording looks set to be faced with one of its biggest potential U-turns in years. Not since the IGFA pointed out that some of the Porbeagle Sharks UK anglers were claiming as world line class records were in actual fact Mako's have fish recorders been faced with the dilemma of trying to sort out who holds which record and with what. That said, with 'two species' potentially merging into one, this time around it should be a whole lot easier, with the heaviest example filling the new single species slot. And the reason for this, in a nutshell, is a scientific paper recently published looking at the mitochondrial DNA of smoothhound species, both with and without the white spots, from various locations around Britain and Ireland, which so far has failed to turn up a single Common Smoothhound specimen in its four years of operation. Why, because contrary to both popular as well as scientific misconception, while there is such a species as the Common Smoothhound Mustelus mustelus, based on this study, it appears not to reach as far north as the British Isles, and indeed may never have done so.
These are the findings of University Collage Dublin (UCD) Ph.D researcher Edward Farrell published in the ICES (International Council for the Exploration of the Sea) Journal of Marine Science in January 2009. This is something Irish Fish recorders have been arguing for many years by listing just the single inclusion of 'Smoothhound' for all specimens, with or without spots. Ed's paper, written in conjunction with Dr. Stefano Mariani of UCD, and Dr. Maurice Clarke of the Marine Institute, is only an extract of what will become a far wider ranging thesis to be published very probably towards the end of 2009. Using tagging, the project also looks at the recent increase in smoothhound numbers and expansion of their distribution, a strand funded by Ireland's Central Fisheries Board (CFB), and includes fish taken this side of Irish Sea aboard Gethyn Owen's Holyhead based charter boat 'My Way'. In fact, Ed was at Holyhead in late May with Gethyn for more work on the project to which I had an invite. Unfortunately, the weather had other ideas. So no new DNA samples were shipped back over on the ferry. But plenty of tags were left for Gethyn to use in the quest for more distribution, migration and population data, which again could have major implications for sea anglers throughout Britain and Ireland.
Smoothhounds it would seem are one of sea anglings recent success stories. Certainly in our corner of Europe, though not in the waters off other parts of the EU where their flesh is regarded as being superior to that of other commercially sought shark species. So now would be a good time to take steps to protect them in line with other cartilaginous species such as Tope and Common Skate rather that the usual policy of waiting until they are teetering on the brink of extinction. Along my local patch of Lancashires Fylde Coast, smoothhound numbers have been increasing for quite a few years from a point back in the 1980's when I can't recall ever seeing any at all. In line with the forecasts for this trend, this year has been exceptionally productive with us taking dozens of small specimens on lugworm while fishing for Plaice, and good numbers of better fish on squid while fishing for early Tope and rays. We've always picked up the odd one on squid over the years. But if you really wanted to get amongst them it had to be crab. Now however it seems that there are so many about they are competing for other types of food with other species of fish. And mirroring reports from elsewhere in the country, the ratio of non spotted fish to those with spots seems to be around 1 in 5.
As a scientist, I know that in evolutionary terms, two seemingly identical and closely related species, be it fish or whatever, never totally occupy exactly the same niche. Either there is some slight habitat or feeding difference, or the less competitive of the two species is displaced and disappears. That's the way it works. So why then should smoothhounds be any different from all that has gone before. To all intents and purposes, both of the so called species freely mix and occupy the same feeding areas, and both take exactly the same baits presented in the same way in preference to other techniques and baits used by anglers fishing the same areas either for smoothhounds or for other species. That said, the spotted starry variety is at times caught in isolation, though without doubt because of its bigger 'population' numbers which would make this statistically more likely for no other reason than the law of probabilities. I can't think of any situation where the numerically less abundant and inappropriately named Common Smoothhound can be deliberately and successfully targeted in isolation because it occupies a different ecological niche, which to me is a clear example of 'within species' variation. That however is anecdotal and not worth a blow on a trumpet so far as hard science goes. DNA evidence on the other hand is quite another matter.
As the DNA markers slide very clear shows, the 'hard' evidence IS conclusive. The four markers for the Starry Smothhound, both with and without spots, are positionally distinct from the marker for the true Common Smoothhound, the DNA for which was provided from a specimen taken outside British and Irish waters. Actually, the Starry Smoothhound markers are closer to that of the Tope which is far more distantly related than is the Common Smoothhound, which for angling could prove to be of more importance than simply identifying potential record fish. As was mentioned earlier, elsewhere in Europe, smoothhound species are considered to be superior to, and more valuable than, many of the other commercially important shark species, and as such have taken a real hammering. So an increase in population numbers, while it may be good from an angling point of view in the short term, could pose a genuine threat to angling in the longer term. And while EU legislation protecting endangered shark and ray species was enacted during 2008, this did not include smoothhounds, though it does cover Tope, which could be a loophole that needs to be closed. It is illegal for anyone to bring Tope ashore throughout the EU, but not smoothhound species. Now imagine the problem fishery protection staff would have trying to separate small Tope steaks prepared for the market from large smoothhound steaks. Previously it would have been nigh on impossible. But now, using Ed Farrell's DNA markers, that would no longer be a problem, potentially nipping illegal landings of Tope in the bud.
Getting back to the problem that Ed's work poses for the British Record Fish Committee, ironically, as the boat record for both 'species' is exactly the same at 28 pounds at the time of writing, there shouldn't be too much in the way of opposition to a merger as both would become joint records, though I hear on the grapevine that a claim for a bigger Starry is currently in the pipeline. Merging the British shore records, and also the Welsh and the Scottish records will however result in winners and losers, another irony being that both the Welsh boat records were set at Holyhead, and the Starry aboard Gethyn Owen's 'My Way', the very boat that has done so much to bring the current situation to a head, with the Common, if there still is such a thing, having been caught aboard 'Spin Drift'. But tackle it they must, though my confidence in the British Record Fish Committee is, I have to say based on past experience, extremely low. The reality however is that it's going to be difficult for them to do anything other than accept the fact that what they currently call Starry and Common Smoothhound's are in fact one and the same species. Expertly gathered DNA evidence taken from 431 specimens, both with and without spots, all pointing to a single species source more than passes any legal burden of proof test, with courts throughout the European Union happily handing out life sentences to murderers on less compelling evidence than that.
Anyone interested in knowing more about the project can additional information from Ed Farrell's website at www.ucd.ie/
FOOTNOTE
If the fish recorders do bow to this indisputable scientific pressure, then perhaps they should also re-visit the Anglerfish record in light of the fact that two almost identical species have now been shown to live in British and Irish waters. Which of the two species holds the record?. Or perhaps I shouldn't ask. Least ways not until they've sorted the smoothhound situation out.