Much of that nitrogen once flowed into the bays via groundwater and leaching septic systems. Clams are filter feeders. If I were a clam in the Peconic Bay last July and trying to fatten up to reproduce, I would have to pump four times the amount of water to get the same amount of food as a clam did in the Great South Bay in 1975. Super Clams Mr. Tollefsen said the venerable Blue Point company, with shellfish farms in the Great South Bay, went out of the clam business this year because it was taking 10 years to grow a clam to marketable size. He said his theory was consistent with the observation that the brown tide seems to coincide with drought periods.
Rain increases the amount nitrogen via road runoff and groundwater infiltration.
There's no brown tide. There was lots of rain in the spring, but none in the summer. The scallops started to grow, but then stopped growing. He points to Lake Erie where in the 1960s algae nearly choked the life out of the Great Lake. Phosphorous is the problem nutrient in freshwater and efforts were made by Canadian and United States officials to keep it out of the lake.