Lost World
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More than 20 years ago, in an attempt to assess the ecological impacts of the cod's disappearance in the Gulf of Maine, Bob Steneck spent months monitoring predator-prey interactions along an undersea mountain known as Cashes Ledge. Free from groundfish draggers that hauled millions of pounds of cod elsewhere in the gulf, the area was home to a relic population of big cod that dominated the ecosystem. In this lost world, the pressure of predation kept the number of small lobsters down, leaving only the fittest to grow large enough to avoid being eaten. The large predators kept the populations of smaller species in check and the system in balance.

Steneck used the data from Cashes Ledge as a springboard for archeological research, conducted in collaboration with colleagues from Bates College. By sifting through fish remains in an ancient midden discovered on an island just off the Maine coast, he discovered evidence that suggests that changes in the marine ecosystem caused by humans may have begun to have an effect on cod populations much earlier than previously thought. Bones collected from the midden show a dramatic change in the early inhabitants' eating habits, switching from a diet almost exclusively of cod to one that included smaller species like flounder and sculpin. The change could reflect a localized impact by humans on the marine ecosystem nearly 2,000 years ago.

The two projects offer insights into just how much the Gulf of Maine ecosystem may have changed since humans began hauling fish from its waters.