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The Northeast skate complex consists of seven species, five of which are common in the Gulf of Maine. However, no scientific data exists for four of these fish. With funding from the Northeast Consortium, Captain Joe Jurek and UNH researchers Paul Tsang and James Sulikowski are working to fill this void by collecting biological data from smooth and thorny skates. Results from this collaborative research project on the life history of these two skate species are coming in at a critical time as the New England Fishery Management Council (NEFMC) is moving forward on a new fishery management plan (FMP) for all species in the Northeast skate complex.

Why is there a need to study skates? According to the NEFMC and the Northeast Fisheries Science Center (NEFSC) some skates are being or have the potential to be over-fished in the Gulf of Maine. In the past, skate were collected indirectly during ground fishing operations and usually discarded as by-catch. However, the rapidly expanding markets for skate wing and lobster bait have made some of these fish commercially more viable in recent years, especially in the western north Atlantic. Yet, there are no current regulations for harvesting four of the five species common to the Gulf of Maine.

Sulikowski raises a very important issue about the development of a management plan for each Gulf of Maine skate species: "If there is no background information about their biology and ecology, how is a new Fisheries Management Plan going to work for these specific skate species?" As a scientist, Sulikowski can really appreciate the implications of this research. "An important aspect of the (Northeast) Consortium is that it's giving us scientists an opportunity to collaborate with the fishing industry so that we can collect the biological information necessary for the successful development of a fisheries management plan for smooth and thorny skates."

Part of the problem with skates is that the larger ones are targeted for their preferable wing size which could result in a biological crisis. Skates are categorized as a K selected species, which means they reach sexual maturity at a relatively old age and are longed lived. Moreover, depending on the species, one female can produce as few as 30 eggs a year. If these large individuals are removed by fishing, this can have a serious effect on the population as a whole. Currently, smooth and thorny skates have no identified reproductive cycle in the Gulf of Maine, which makes studying their life history even more important for management purposes.

Luckily for Dr. Tsang and Sulikowski, fisherman Joe Jurek of F/V Mystique Lady also has an interest in the biology of skates. "I have an interest in all biology. That's why James and I get along so well." At first it was difficult to locate the skates, but Jurek's interest in biology, and his experience and expertise as a commercial fisherman helped to overcome this problem, and since then the monthly collecting trips have been very successful.

After the skates are caught, they are brought back to the Coastal Marine Laboratory where UNH undergraduates Scott Elzey and Jeff Kneebone assist in processing the skates for biological analyses. Here Elzey and Kneebone are involved in everything from skate dissection to fine processing of their tissues. One aspect involves determining the age of the skates by counting rings of calcium deposits in the vertebrae just as one would age trees by counting rings in a cross section of a tree trunk. This information will be used to help the researchers explain age and size at sexual maturity for both skate species.

The results so far have been promising, and it appears that the project will come to completion earlier than the participants anticipated. One unexpected observation, however, has been the extensive prevalence of smaller, sexually mature individuals within the population. Project participants were wary of this phenomenon at first and wondered if these individuals were anomalies, but as sampling continued, these smaller, sexually mature individuals were increasingly abundant, which has lead to even more questions. Is there a shift toward a smaller reproductive size in skates? This would certainly be a favorable adaptation if the larger and older skates are being selectively removed from the population.

The collaboration between fisherman, scientists, and students has become a valuable partnership. Sulikowski's satisfaction in the progress of the project is largely due to the success of the research-industry relationship. "We couldn't have asked for a better working relationship with Joe. His time, interest, knowledge and expertise have been invaluable to us and the project. I consider him not only a partner but a friend as well, and I hope in the future we can continue to use this relationship to further skate research in the Gulf of Maine."