The acknowledged shark researcher Dr Steven E. Campana from Bedford Institute of Oceanography is responsible among other things for stock assessment of commercially used shark species off Canada’s east coast.
Schillerlocken (curled strips of smoked spiny dogfish) used to be an ever-present delicacy in the counters of German fishmongers, and their presence was taken for granted. Because the dogfish stock in the North East Atlantic is overfished, however, an increasing number of grocery chains no longer lists the products of this presumably endangered species. Now the fishermen on the east coast of North America are complaining. There are still plenty of spiny dogfish there but hardly anybody wants them. What is to be done? Should dogfish products be taken out of the product range or can they remain there?
In May 2009 Fish Information & Services (FIS) reported that US-American east coast fishermen were complaining about hefty increases in spiny dogfish stocks. The stock biomass of this shark species which is considered to be threatened in our region had risen to 4 billion lbs, about 1.8 million tonnes. Although Dr Steven E. Campana from the Canadian Shark Research Laboratory at Bedford Institute of Oceanography in Dartmouth (Nova Scotia) agrees with the essence of this announcement he gives a more differentiated picture. Basically, spiny dogfish (Squalus acanthias), also called piked dogfish or spurdog, is probably the most abundant shark species there is. Based on rough estimations there could be nearly one billion of the species swimming throughout its distribution area which includes all of the world’s oceans. Dr Campana cannot say with sufficient certainty how big the spiny dogfish population off the east coast of North America actually is until September, however, when the results of the latest stock assessment are due. In January 2010, Campana and his team had for the first time carried out a stock estimation in this marine region in co-operation with their colleagues from the USA. This step was long overdue since all the spiny dogfish schools that are to be found off the Atlantic coast of Canada and the USA belong to a connected population. This means that it does not make sense for each party to undertake its own assessment. The data still haven’t been fully evaluated, however, and Campana does not want to make any statements until both parties have approved the results.
Whatever the outcome of the investigation the acknowledged shark researcher already cautiously points to the fact that the spiny dogfish is not only one of the most abundant shark species, but also one of the most strongly threatened worldwide. Their total numbers had shrunk alarmingly throughout the world during the last two decades, undoubtedly as a result of overfishing. It would be wrong to be deceived by the seemingly relatively large number of dogfish that have been left swimming in the seas because this viviparous shark species was not very productive which made it particularly susceptible to overfishing. In the North Atlantic (NA) spiny dogfish females do not reach sexual maturity until they are 15 or 16 years old, and in the North East Pacific (NOP) they have their first young at an age of 23 to 32 years. At this point in time they are already 82 cm (NA) or 94 cm (NOP) long. The males develop somewhat faster: in the North Atlantic they already reach sexual maturity after 10 years when they measure 64 cm or in the North East Pacific after 14 years at 70 cm. The females carry their young for 18 to 22 months so that these dogfishes can only reproduce every two years. The first litter usually produces only two to three young fishes, measuring 18 to 20 cm. The bigger and older the females become the more numerous and larger are their offspring which increases their chance of survival considerably. It is not exactly known up to what age spiny dogfish can have young (presumably up to 25 years in the Atlantic and about 40 years in the Pacific) but up to 15 shark babies measuring 30 cm have been found in the bellies of older females.
The facts that spiny dogfish take a long time to reach maturity and have a low reproduction rate are exacerbated by the species’ extremely slow growth. Analyses of the growth zones on the spines in front of the dorsal fins have revealed that these fishes grow a maximum of 3.5 cm per year. And occasionally growth will only amount to 1.5 cm, as examination of tagged individuals has shown. To make up, spiny dogfish live to a very old age. In the Atlantic 35 years for males and 50 years for females are no rarity. And in the Pacific they are said to be able to live to an age of 80 or even 100 years. These conditions could hardly be less favourable for a targeted fishery since the dogfish stocks take a long time to offset any losses. Even if the populations in the Atlantic were left fully undisturbed without any fishing activity the number of individuals in the stock would increase by only 4 to 7% per year. If the fishery removes one tenth of the stock, for example, it will take 1.5 to 2.5 years to make up for the losses. Added to this is the fact that spiny dogfishes form large shoals of fishes of the same size and same sex. This increases the risk that the reproduction potential of the population will be selectively reduced since the fishery mainly targets large females, i.e. the very fish that are so valuable for stock maintenance. As a result of strong fishing activity the share of females in the stock in a lot of areas is only one third, and even only one fifth in the North Atlantic.
Europe is the main market for spiny dogfish products
Up to now, only a few of the numerous spiny dogfish populations that there are in the world are monitored on a regular basis and only a few of the fisheries are carefully managed. Our knowledge of stock dynamics, boundaries and size is just as fragmentary as our knowledge of the biology of this small shark. Not all the methods in the repertoire of biological tests used in the fisheries sector can be applied to assess spiny dogfish so that when estimating the stock it is necessary to rely on evaluations of Catch Per Unit Effort (CPUE), development of landed volume, and specific tagging experiments. Spiny dogfish are often not sufficiently distinguished from other small sharks in the catch, particularly if they are caught as by-catch. This means that only vague assumptions are possible on how many dogfish are actually caught beyond the approved quota for any individual region. The FAO already complained in 2007 about the poor documentation of landings, and demanded improvements. This has been without noticeable success so far, however, because the records on international trade with spiny dogfish products are often incomplete. Only a few states, among them the USA, Canada, Norway, Chile, Argentina and New Zealand document spiny dogfish trade in accordance with the common standards. Other countries such as Turkey which is said to catch 85% of the spiny dogfish in the Black Sea, submit incomplete reports or none at all.
In contrast to a lot of fish species spiny dogfish is not marketed as fillet. The belly flaps and fins are removed, the body is skinned and the fish is then traded as ‘white loin’ or ‘back’. There are eager markets for each of these products. The belly flaps are particularly popular in Germany where they are smoked and put on the market as ‘schillerlocken’. Frozen fins are mainly exported to Asia where they finish up in Japanese or Chinese restaurants. Backs, interleaved or frozen in blocks mainly go to the UK where they are used for fish and chips, or to other countries in continental Europe. In Germany they are also known by the misleading name ‘Seeaal’ (sea ee
l). Even the dried cartilaginous skeletons of spiny dogfish are used in the nutraceutical industry for the production of foods with pharmacological effects.
Europe is by far the most important market for spiny dogfish. In the 1960s and 70s when a dozen European countries, led by Norway and Ireland, fished dogfish shoals in the North East Atlantic, the annual catches regularly amounted to around 40,000 t, sometimes even reaching nearly 50,000 t. If the catch volumes taken from the North East Atlantic between 1950 and 2006 are added up and compared to other marine regions it soon becomes clear that during this period of time more than 85% of worldwide spiny dogfish catches came from the North East Atlantic. For a fish with such a low reproductive capacity this was ruthless exploitation that could not be without consequences for the stock: spiny dogfish is today considered to be totally overfished in the North East Atlantic. The biomass of the stock is said to have shrunk to less than 5% of its original level. The IUCN rates “North East Atlantic spiny dogfish” as “threatened by extinction” in its Red List of endangered species. Viewed in this light the management and protection measures that have been introduced by European states seem rather half-hearted.
Binding fishing quotas (TACs) were already introduced for spiny dogfish in EU waters in 1999 but up to 2007 they only applied to the ICES regions IIa and IV. Up to 2005 the fishing quota was also set so high that the actual landings were well below the named figure meaning that the fishery was in no way restricted. Even the 2009 quota still permitted a catch of 316 t of dogfish in the ICES regions IIa nd IV. The TAC for region IIIa which corresponds more or less to Skagerrak and Kattegat was set at 104t, and a further 1,002 t were permitted in the regions I, V-VIII, XII und XIV. As a more effective means of protecting the big females which are so valuable for reproduction, the maximum size of the landed fishes was also limited to 100 cm. Only in 2010 did the European Commission decide to set the TAC at 0 t, i.e. to close the spiny dogfish fishery completely. Late – but hopefully not too late.
These measures have hardly diminished Europeans’ appetite for schillerlocken and other dogfish specialities. At the beginning of this decade European countries were still consuming 20,000 t of spiny dogfish per year, with half of this quantity coming from their own fishery, the other half from imports. Since then, although demand has fallen because a lot of consumers are worried by reports of overfishing of sharks and hold back from buying the species, it still fluctuates at around 3,000 to 4,000 t per year. This demand is almost solely satisfied by imports. Nearly 70% of the imported dogfish that we eat today in Europe come from the USA and Canada. Both countries catch dogfish both in the North East Pacific and in the North West Atlantic.
North American stocks in considerably better condition
A hundred years ago spiny dogfishes were considered a nuisance by North American fishermen: they caused damages to the nets and thus unnecessary work and the fishermen had no further use for them. Buyers could sometimes be found for the livers which were rich in fat. This was used to make lamp oil and lubricants for machines. Shark liver was at that time also of some significance as a raw material for vitamins. It was not until the early 1960s when the Europeans were already catching about 40,000 t per year that spiny dogfish became more interesting for Canadian and US-American fishermen, too. Up to the end of the 80s the catch volume remained relatively modest at around 2,000 to 3,000 t. When a small dogfish industry developed in Canada as from 1995 the catches gradually rose, however, reaching a stable level of just under 10,000 t after the start of the new millennium. This fishery is divided up almost equally between the Atlantic and the Pacific.
When targeted specifically dogfish are mainly caught using longlines and hand lines which are baited with herring or squid. Occasionally, gill nets and trawls are also used. The fishery begins at the end of spring when the shoals move northwards along the coasts on their migration and usually ends at the beginning of autumn.
As the catches in the North East Atlantic diminished the Europeans began looking for alternative sources in other parts of the world. This generated export opportunities for the Canadian fishermen whose interest in spiny dogfish rose accordingly. A fishing quota of 2,500 t was thus set for Atlantic Canada for the first time in 2002 – this was linked to a stipulation that the fishery contributed to collecting basic scientific data. A year later the quota rose briefly to 3,200 t but was reduced again to 2,500 t in 2004. This TAC has remained the same to this day but has never been fully utilized since 2004. In the year 2009 Canadian Atlantic fishermen only caught 140 t because the Europeans were buying less and less dogfish. Parallel to the fishery the spiny dogfish stock has been subject to intensive scientific investigation for years. The results of the Canadian spiny dogfish research programme have revealed that the biomass of this species adds up to at least 300,000 t in the Canadian waters of the North West Atlantic.
Dr. Steven Campana, Bedford Institute of Oceanography, CanadaAlthough this seems a lot compared to the fishing quota of 2,500 t, shark researcher Steven E. Campana points out that the TAC is currently not deduced on a scientific basis but is set arbitrarily. Only when the results of the assessment carried out together with the USA are available would it be possible to say whether this quota is really within safe limits. His cautious approach is understandable since although Canada and the USA fish the same spiny dogfish stock they do so with very different strategies. Whilst the Canadians catch both dogfish sexes the US fishermen mainly target the big females that are particularly valuable for the survival of the population. (schillerlocken are allegedly only made from the belly flaps of female fishes). No one knows how the stock will be able to cope in the long run with a fishery that targets only the females; and the effects of spiny dogfish by-catches in other fisheries in the area are also unclear, particularly since experiments carried out recently with tagged dogfishes suggest that there is not such an intensive exchange between the populations off Canada and the USA as previously assumed. Only 10 to 20% of the spiny dogfish migrate north from US waters. In the project ‘Ocean Tracking Network’ (OTN) researchers now want to find out whether the fishes migrate back and forth regularly or whether
migration is only in one direction.
There are already signs that the specific targeting of females could lead to problems. During the last investigation in 2009 the Northeast Fisheries Science Center could not discover any indications of overfishing but pointed out that relatively few fishes were found measuring over 100 cm and under 70 cm. The absence of larger mother fishes and their young is already clearly noticeable for the stock is currently dominated by dogfishes measuring between 75 and 95 cm. The scientists thus expect to see a tendency for the population to diminish slightly up to 2017. That is probably also why the Atlantic States Marine Fisheries Commission (ASMFC) reduced the fishing quota for 2010/11 to 15 m lbs (about 6,800 t) and demanded that spiny dogfish by-catches be reduced. There is a good chance of this because every second dogfish that is caught in a trawl survives being thrown back into the sea. With gill nets the survival rate is between 30 and 55%.
MSC certification in Canada and the USA imminent
In both Canada and the USA fishermen were against the attempt to place spiny dogfish on the Annex List II of CITES (Convention on International Trade in Endangered Species). This listing would mean a tremendous amount of work to get every single delivery of spiny dogfish approved and would thus make exports to Europe practically almost impossible, feared Steve Barndollar, the President of Seatrade International Inc., one of the three most important spiny dogfish exporters in the USA. The organisation “Fishermen Organized for Responsible Dogfish Management” was founded and engaged a legal office experienced in such matters. They managed to gain the interest of about 20 influential senators from the US Congress for implementing their interests. Their main argument sounds absolutely plausible: If the Europeans have overfished their spiny dogfish stocks in the North East Atlantic that doesn’t mean by a long way that all the other stocks in the world are in a similarly pitiful condition. The North American spiny dogfish stocks are at any rate not overfished and are used sustainably. That is why there is also no reason to try to limit the export of dogfish products by bureaucratic regulations… particularly since a measure like that would have no influence on European fisheries policy to handle this resource more carefully in the future.
For North America’s spiny dogfish industry an 80 to 100 million dollar business is at stake and this business is only worthwhile if all the products arising from it can find buyers: fins in Asia, backs in England, France, Italy and Belgium, and belly flaps in Germany. If only one of these buyers is lost, exporting dogfish could become unprofitable, says Christian Brun, too. He is the Manager of the Maritime Fishermen’s Union in New Brunswick. Over the past two years business had become increasingly difficult because demand for belly flaps by German customers had collapsed by two thirds. That was why they saw themselves forced to throw 50% of the belly flaps away, regrets Louis Juillard, the Export Manager of the US company Marder Trawling.
Figis, FAOUnder pressure from environmental organisations German grocery chains in particular, but also increasingly French ones are demanding that spiny dogfish suppliers should seek MSC certification. That would be the only way to show consumers that the fish comes from sustainably managed, unthreatened stocks. Seatrade International Inc. (Massachusetts), Marder Trawling Inc. (New Bedford) und Zeus Packing Inc. (Gloucester), the three most important spiny dogfish processors in the USA and in fact competitors thus joined forces and already got the MSC certification process going in spring 2009. The final report of the preliminary examination on 28 September confirmed that the US spiny dogfish fishery in the Atlantic has very good chances of being granted MSC certification. The three companies wanted to wait until March 2010 for full certification in order to await the decision of the CITES conference. The planned MSC certification costs about 90,000 dollars and if spiny dogfish exports are rendered almost impossible by the CITES regulations they could save themselves the expense.
The Canadian spiny dogfish fishery in the Atlantic also wants to gain MSC certification. And as in the USA the pre-assessment was positive. Steven E. Campana, the shark researcher from Bedford Institute knows, however, that the commissioned certification agency wants to await the stock assessment which Canada and the USA have carried out for the first time together. If they get a green light the process will begin in autumn.
The spiny dogfish fishermen on the Pacific coast of Canada have already advanced further: the hook and line fishery of British Columbia is undergoing MSC certification. On 12 March 2010 MSC announced on its internet site that the certification office Moody Marine had entered the phase of information collection. From 19 to 23 April talks were planned with representatives of the fishery, fishery management and other participants. If nothing untoward comes up certification could probably be awarded at the end of 2010 or in early 2011.