When most of us look out over the waters of the Gulf of Maine, we tend to see things in two dimensions; the water looks pretty flat and it stretches out toward the horizon. Fishermen, however, make their living in the Gulf of Maine by thinking of the water in three dimensions—they are constantly observing what is happening in the water and figuring out what the bottom under them looks like. Successful fishermen take note of the temperature of the water, the direction of the currents and who is eating whom. Scientists think of the Gulf of Maine in four dimensions, the three dimensions above plus what is happening in the Gulf of Maine over time.

During the past five years, we have gathered some of the region’s most energetic scientists and experienced fishermen together on a regular basis at annual “Lobster Roundtables” to trade information on what they have been seeing in the Gulf of Maine and how the ecosystem is changing. Lately, some of the observations have left a disturbing impression, especially about rising water temperatures.

Diane Cowan, a lobster biologist with the Lobster Conservancy in Friendship, Maine, who has contributed to the roundtables, has also recently suggested that the abundant lobster catches during the past few years should not just be cause for celebration, but rather cause for concern. She has seen more and bigger lobster boats chasing young lobsters, that have not reproduced yet, further offshore in the winter, where they used to have some respite before being fished up. And when lobsters crawled back toward shore this spring and began showing up as shedders in lobstermen’s traps six weeks earlier than usual, many lobstermen became concerned what the warming of the waters means for the ecosystem of the Gulf of Maine.

Meanwhile, we are aware of another report from the other end of the Gulf of Maine, where the currents rise up over the shoals on Georges Bank and stir a rich broth of nutrients over some of the most productive fishing grounds in the world’s oceans. According to Ron Smolowitz, a retired NOAA Corps officer who has been conducting fisheries research and fishing gear development for almost 40 years, testified at a recent New England Fishery Management Council meeting. “I have big concerns,” he told the council. “There’s something significant going on out there independent of the fishery. There’s a fishery without large fish, fish are underweight and not replacing (themselves). Something is wrong with the fish that (has) nothing to do with fishing.”

What everyone worries about in any marine ecosystem is what is going on at the bottom of the food chain—especially with those creatures called phytoplankton and zooplankton that bloom in the Gulf of Maine and Georges Bank’s rich watery pastures. These microscopic creatures, which scientists study, are the food on which small grazers feed, and which become food for larger fish that feed on them and so on up to the populations of lobster, cod, haddock, pollock, flounder, halibut, tuna, whales, seals and seabirds that all ultimately depend on this source of food we cannot see with our own eyes. The timing of egg laying and larval (or baby) fish development is closely synchronized with these blooms of tiny marine plants and animals. If changing temperatures or currents affect the timing of the spring phytoplankton bloom, pushing it either earlier or later than the timing of fish development, an entire year class of fish can disappear with no one the wiser—until it may be too late.

Of course, Cowan and Smolowitz’s comments are only two observations at different ends of the Gulf of Maine among the thousands and thousands of fishermen and scientists who everyday both work and study this highly complex marine ecosystem. But still”¦it should give us all pause.

Perhaps we should be grateful that no legislators in this region have taken the approach recently favored by lawmakers in North Carolina. There, a group of scientists recently predicted that sea level could rise by as much as 39 inches along the North Carolina Coast during this century. Legislators did not seem particularly concerned about what this could mean to North Carolina’s fisheries, but they were horrified about what it could mean for flood insurance rates and future of real estate development. So they did what only politicians can do—they wrote a law that basically would outlaw the use of climate change projections in formulating state policy. In effect, they said, “We declare sea level rise illegal!” Maybe the North Carolina state motto should be “Come on Down—The Water is Warming!”

Seriously, everyone, it’s time to pay attention. We need to figure out what is happening not just with water temperatures and sea level rise, but with the intricate food web in an intensively utilized marine ecosystem that sustains thousands of fishermen and hundreds of fishing communities around the rim of New England and Atlantic Canada.

Philip Conkling is president of the Island Institute based in Rockland, Maine.