Dan's Papers - July 3, 2009 - Stony Brook Students Say: Let Bivalves Be Bivalves

"Damaging nutrients." Now there's an oxymoron. But the fact is, what's good for the goose isn't always good for the gander. And nutrients like nitrogen and phosphorus are currently having a deleterious effect on our local waters - and may just impact your selections at the raw bar.

Students from Stony Brook Southampton have been using the local bays and ponds as research labs. Under the guidance of Chris Gobler, they've studied the effects of excess carbon dioxide on shellfish, algae blooms in both fresh and salt water bodies, and the juvenile fish kill rate due to the water cooling process of the nuclear power plant in Northport.

Their findings are no surprise: They show that increased development in our area over the course of the 20th century, the need for more energy and global warming are all having a distinct and negative effect on our marine, estuarine and fresh water environments. The increase in population growth has been directly linked to the decline in marine resources. Long Island used to produce over 85% of the shellfish consumed in the United States. Think about it: two out of every three clams came from Great South Bay.

But that was then, this is now.

Our local bay system has been placed on the New York State "impaired estuaries" list, which focuses on contamination. The toxic algae know as brown tide had a banner year in 2008. It started in Great South Bay, moved east to Shinnecock Bay and didn't die off the way it usually does. Burgundy tide and red tide also surfaced in our waters last year, most notably in Peconic Bay in the middle of last summer. (You might remember the large patches of purple water.) Brown tide is aptly named, as the water turns murky and opaque. Needless to say, it's unappealing to swimmers and toxic to shellfish. This algae also blocks the sunlight that can penetrate into the water. Less sun means fewer eel grass beds. Few people know or care about eelgrass. But a lot of folks like scallops. Eelgrass is necessary for a developing scallop, which clings onto it during their most vulnerable stage of life.

Increased carbon dioxide levels in the air have led to increased carbon dioxide levels in the oceans and bay waters. That raises the water's pH, interfering with the shellfish's ability to use calcium - a necessary ingredient for shell production. This could mean fewer clams on the half shell for all of us. Hard clams produce thinner shells and in some extreme cases, the hinge that all bivalves (like mussels, oysters, clams and scallops) need to open and close their shells may be damaged. In other words, the clams can't clam up, making them vulnerable. The scientists have noted a 99% decline in hard clam harvest - a disaster for shellfish, not to mention the future of the time honored clambake on the beach.

Happily, there was some bright news in the scientists' presentations. Scallops are being farmed successfully in Orient Harbor. At the Peconic Land Trust's Oyster Hatchery run by Karen Rivara, tasty bivalves are being brought to maturity and then to the dinner table. (One audience member pointed out that throwing the shells back in the bay after you cook 'em, may actually help with the calcium/shell forming problems.) Crabs still go after scallops - that remains an issue as since the crabs' predators, finfish have declined. (One theory is that they're being sucked into pipes that provide coolant for nuclear reactors, resulting in a 45% mortality rate.) But fewer finfish is good news for lobster lovers: the lobster population may increase since finfish dine on baby lobsters. And it may be that scallops are finding refuge in a type of seaweed that's presently considered a pernicious weed - but it's far more resistant to water quality changes than eelgrass.

It was evident by the end of the presentations that one change in the marine environment starts a domino effect that encompasses all the critters that live underwater.

No other topic is as hot as nutrient loading into our surface waters right now. Next to carbon dioxide it's a main contender in putting the bays on the impaired estuaries list. Chris Gobler noted, in summation, that run off from septic systems is a priority on the list of clean up issues being addressed by municipalities across Suffolk County (this issue is currently being explored in Lake Ashawagh in Southampton and Havens Beach in Sag Harbor). Septic systems will have to be brought up to code to keep nitrogen and phosphorus out of the bays. In fact, note to homeowners, if you're planning a renovation or addition, this issue will come into play. Updated septic systems may be a bit costly and time consuming, but if it means cleaner water to swim in and a healthier shellfish industry then perhaps we should seriously consider it.

There are new regulations already in place. Fertilizer use is now limited between April 1 and November 1, and forbidden on property within 20 feet of a body of surface water (ignoring that regulation means a $1,000 fine for both home owners and landscapers). This could help keep those "damaging nutrients" out of the local waters, keeping it cleaner for us to swim in and healthier for shellfish to grow in.