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Villanova biology Professor Michael P. Russell doesn’t pack up his deep-water diving suit just because the calendar says it’s winter. In fact, on Dec. 14 Russell drove north to dive in Maine’s Piscataqua River--but not just for fun. The Villanova biologist is making the dive as part of a research project that began in his lab on campus. With a bagful of miniature baby green sea urchins, on Dec. 16, Russell will descend some 30 feet into the icy depths of the Piscataqua, located about 100 yards from the chillier Atlantic Ocean. He will deposit approximately 10,000 juvenile urchins and return one year later to measure their growth. “We will monitor them, as well,” said Russell. “We will dive at the site, get density and size distribution estimates—at least six times during the year.”

The purpose of his mission is to conduct a comparative growth study on the population dynamics of the green sea urchin. Russell is studying how well two experimental groups of green sea urchins that he raised in his lab on campus will survive over one year. During the past year, the professor raised one group in normal sea water and the other group he subjected to low-salinity conditions every two weeks. Next year, he will return to Maine “to dive on these sites and monitor the samples every three months,” he added. The goal is to collect the tagged urchins to see how many have survived. According to the biologist, as long as they have sufficient food, the species does not migrate and will remain in the area where they have been placed.

Russell’s research focuses on the population and larval ecology of commercially important estuarine and marine invertebrates. His recent work has focused on studying the green sea urchin, Strongylocentrotus droebachiensis, in the Gulf of Maine. This research has made valuable contributions to understanding the life history and allocation of the resources for this species, which is considered ecologically and economically important.

The green sea urchin population has wide distribution and significance. Despite this, there were no reliable estimates of the species’ growth and mortality until Russell began his studies. Contrary to popular assumptions about the species, Russell and his colleagues have documented that it is slow-growing and long-lived. Individual green sea urchins may live more than 50 years.

This research is significant to the sea urchin industry that has developed in North America. According to Russell, from 1987 to 1995, the sea urchin fishery in the Gulf of Maine grew exponentially. In 1995, “The Wall Street Journal” estimated the value of the fishery exceeded 70 million dollars. However, since then stocks have dwindled so radically that recent harvests have plummeted, and the fishery is nearing economic extinction.

According to Russell, over fishing of the species in the area has caused the decline of the species. Russell feels it is therefore necessary to have estimates of basic population parameters such as growth and mortality rates to manage any fishery effectively. He has made the results of his studies available to the Department of Marine Resources (DMR), the state agency in Maine responsible for managing this valuable natural resource.

The Gulf of Maine stretches from Cape Cod to Nova Scotia. The green sea urchin has been widely fished there because it is a valuable gourmet food source. In this country, it is used as in sushi bars. In some countries like Japan, it is called “uni” and is considered almost a staple. Most of the urchin population fished in the Gulf of Maine is imported by the Japanese. Russell hopes his research will contribute to the regeneration of the species.