The Chesapeake Bay’s underwater grasses, vital to life in America’s largest estuary, have declined for the third year in a row, Bay scientists announced today. The grasses, which help juvenile crabs hide from predators, slow erosion and filter pollution from the water, had been staging a slow comeback in the first few years of this century. But traumatic weather events have cut the beds back to 1986 levels.
Lee Karrh, head of the Chesapeake Bay Program’s sub aquatic vegetation work group, said the northern Bay, roughly from the mouth of the Susquehanna to Annapolis, was inundated with sediment from Hurricane Agnes and Tropical Storm Lee in 2011 and the grasses still haven’t recovered.
"In the lower part of the bay there was a very strong heat stress on one of the species of grass that lives down there and caused their populations to decline. And we’re not seeing a recovery from the 2010 event."
There was one bright spot, however. The grass bed in the Susquehanna Flats, which bore the brunt of the 2011 storms, wasn’t as badly damaged as scientists had feared.
"It’s significantly smaller than it was, but it’s still in pretty good shape. We just hope it will expand back out."
The numbers show that scientists are barely a quarter of the way toward reaching the goal for grasses they set more than 25 years ago. The study was completed just weeks before Superstorm Sandy hit.
You can view the Chesapeake Bay Program's interactive website here.