Wednesday, January 28, 2009

Goblin girl on... red list assessments.

Now I'm back at home after a meeting with my fellow "fish geeks"- or as we more officially are called "the expertgroup on fishes". We are 7-8 biologists who currently works on an update of the Swedish red list for 2010. There are national red lists around the world as well as a global red list following guidelines from IUCN (= the International Union for Conservation of Nature). The red list list both commercial and non commercial species and the system is designed to determine the relative risk of extinction.

I've been a member since before the update in 2005 and I must say that it isn't easy to do these assessments. We use all data we can find from surveys, landing data from fisheries and other sources, but the red list works best for animals on the savannah! We can't say that there are exactly 253641 spiny dogfish left in our waters and that last year it was 398526. We are not even totally sure that there is just one population of spiny dogfish in the NE Atlantic! Still, the spiny dogfish is one of the few elasmobranch species that we at least have SOME data on. For many of the skates and rays we don't have a clue of age for sexual maturity (which means that we don't know the generation time which is an important factor in the assessment) and we lack landing data specified down to species. All we know is that they are probably late in getting in mature and long lived.

Ever since I made my masters thesis on spiny dogfish (back in 1997) I have tried to make my colleagues set a quota on it in our waters. I mean, an animal that is 12 - 14 years old when it becomes sexual mature and that carries it's pups for 18-20 months (!), can't possibly tolerate a heavy fishing pressure. But since we are part of the European community, we have had to wait until EU finally set a - much to high - quota in 2007. In 2003 came a report most commonly referred to as DELASS (=Development of Elasmobranch Assessments). After having analyzed data and made several models, the conclusion of the report was that in 25 years the population of spiny dogfish in the NE Atlantic might have been fished down with as much as 95-98 %!

With this knowledge, the spiny dogfish was listed as EN (endangerd) on Swedens red list for 2005. The IUCN shark specialist group held a workshop for the NE Atlantic elasmobranchs in 2006 where spiny dogfish got listed under the highest criteria CR (critically endangered). (See figure below for explantions.)

We do these assessments to point out to those responsible that action needs to be taken, but it's not legally binding. The ideal situation is that the red list is blank - that all species are sustainably exploited or not threatend by habitat destruction etc. For some species, the situation is getting better after their debut on the red list, but for sharks action is very slow. Therefore we need people like you, reading this, to take action. Sign that petition, send an e-mail to that shop selling shark products or to a politician that has some power or make an activity celebrating the International year of the shark. Tell everyone that it's not ok to exterminate the sharks!

I'm VERY sad to say that it seems like the spiny dogfish will be listed on CR on the Swedish redlist for 2010. I've done everything I could to change it's dire situation. And it wasn't enough!

1 comment:

Sarah and Stephan said...

I had no idea about any of this, thanks for the post and the update.