Commercial, recreational and party/charter boat fishermen from Maine to North Carolina have all rallied together to deal with an out-of-balance population of predatory spiny dogfish sharks that threatens the recovery of New England groundfish and several others fish stocks living along the U.S. East Coast.

The newly formed Fishermen Organized for Rational Dogfish Management (FORDM) has requested the assistance of Dr. Jane Lubchenco, newly appointed National Oceanic and Atmospheric Administration head, in dealing with the predator.

Spiny dogfish

The disproportionate abundance of dogfish is not a new problem; as early as 1992 Dr. Steven Murawski, now chief scientist of the National Marine Fisheries Service’s, wrote “Given the current high abundance of skates and dogfish, it may not be possible to increase gadoid (cod and haddock) and flounder abundance without ‘extracting’ some of the current standing stock.”

That was over 15 years ago and the situation has not improved. On the contrary, the amount of dogfish now exceeds that of skates, and dogfish comprises over half of all fish taken in the annual trawl surveys carried out by the Northeast Fisheries Science Center.

The spiny dogfish can exceed 150 cm in length and preys on virtually all species of fish smaller than itself. Dogfishes can also create a problem for other species by competing with them for prey fish.

This remarkable abundance of dogfish is most likely the result of countless years of ever increasing over-fishing. Spiny dogfish is not an appreciated food fish and the depletion of other species seems to have favoured it greatly in these waters.

Australian scientists have now completed an 18-month long project aimed at scientifically describing sharks and rays, using traditional techniques as well as modern DNA sequence analysis. The ambitious project has resulted in over 100 species of sharks and rays being properly classified, which is equal to about one third of Australia’s known sharks and rays.

Southern Dogfish Image credit – CSIRO

Over 90 of the new species had already been identified by Dr Last and Dr Stevens in their book “Sharks and Rays of Australia” from 1994, but remained undescribed and without scientific names.

Many of the new species are endangered in the wild, such as the Maugean Skate and the Southern Dogfish, and having them properly classified and named is important for future monitoring and conservational work. The new descriptions and names will be included in a revised edition of “Sharks and Rays of Australia” which is planned for release in 2009.

Maugean Skate Image credit – CSIRO

The 18-month long study was backed by CSIRO’s Wealth from Oceans National Research Flagship. National Research Flagships are large-scale multidisciplinary research partnerships and the National Research Flagships program is one of the biggest scientific research endeavours ever undertaken in Australia.

If you’re interested in the Wealth from Oceans Flagship, you can find more information here. http://www.csiro.au/org/WealthOceansFlagship.html