New Book Explores Shifting Ecosystems in Chesapeake Bay History | WYPR

New Book Explores Shifting Ecosystems in Chesapeake Bay History

Apr 17, 2019

Photo of book cover, "Shifting Baselines in the Chesapeake Bay: An Environmental History," published by Johns Hopkins University Press.

Over the long history of the Chesapeake Bay, those captivated by its beauty have often suffered from landscape amnesia.

We love and want to preserve what we see today: the shimmering waves.  The sailboats, spinnakers full.  The blue crabs scuttling in the shallows.

We want to save all that. But we do not remember the bay our grandparents knew.  The vast reefs of oysters, filtering and cleaning the water. The schools of American shad, swarming up rivers in the spring. The sturgeon, thick as living logjams. Because we never knew it, we do not miss it. And so, as a society, we are unwilling to invest the money and the political capital – and make the changes necessary -- to bring it back.

This phenomenon of ecological amnesia is explored in a new book by Victor Kennedy, a biologist for four decades with the University of Maryland Center for Environmental Science. His book is titled: “Shifting Baselines in the Chesapeake Bay: An Environmental History.”

“There are anecdotes about oysters historically in the bay, like the story told by a Swiss visitor,” Kennedy said.  “The visitor came here and reported that the oysters grew in such masses and reefs that your ship could bump up on them.  He also said that the oysters were huge compared with the ones they had in Europe. In the Chesapeake, he found that they sometimes cut the oysters in two before they could eat them. And then there’s the shells.  I personally have at home a fossil shell that’s probably about a foot long.”

This foot-long oyster was not some dinosaur species of mollusk. It was the same species of Eastern Oyster in the Chesapeake today, Crassostrea virginica. But the new normal for us is a three-inch oyster, because watermen scoop them out after only three or four years instead of letting them grow for 10 or 20 years.

In part because of overharvesting, the bay only has about one percent of its historic oyster population left. And with this loss of natural filtering capacity, the bay has suffered cascading problems that we now accept as normal – including murky waters, algae blooms, and fleets of stinging jellyfish.

“You’ve got more phytoplankton, because the oysters are not filtering it,” said Kennedy. “And more zooplankton, because they had phytoplankton to feed on, therefore more sea nettles -- these stinging jellyfish -- because they had zooplankton to feed on.”

There was a big political fight in Annapolis this spring over incremental legislation that protects five small oyster sanctuaries in the bay that watermen wanted to re-open to harvesting.

Kennedy argues we need to go much further if we ever want to bring back a semblance of the bay’s potential. He advocates expanding oyster sanctuaries and banning power dredging for oysters – which is the dragging of heavy rake-like devices from powerboats that rip up the bay bottom.

“You can certainly argue that power dredging is not something that should be allowed,” Kennedy said.  “The idea is that power dredging is too efficient. And so, with the limited number of oysters out there, you are able to catch more of them, more easily, than with the old fashioned way of sailing and tonging for oysters.”

We need to adjust not only our sense of normal on the bay, but also our expectations. Rising oyster and crab harvests are not necessarily a sign of a healthy bay. In fact, they are often the exact opposite: an indication that we are repeating and compounding the overfishing and exploitation that are the original sins of the Chesapeake Bay’s history.