[If you're visiting thanks to Tom Friedman's kind Dot Earth mention in his column on acting with a long-term perspective, here's a link to the piece he's quoting from.]
John Waldman is a Queens College biology professor and author focused on the bountiful past and potential restoration of the waters of the Northeast. I loved "Heartbeats in the Muck," his history of the changing biology of the 1,500 square miles of New York Harbor, and am enjoying his new book, "Running Silver: Restoring Atlantic Rivers and Their Great Fish Migrations," which achingly describes the bygone biological bounty of eastern waterways and lays out strategies for bringing back at least a hint of that richness.
The book does for river-spawning fishes what Callum Roberts' great book "The Unnatural History of the Sea" did for marine species.
Waldman got in touch recently to let me know that today is the inaugural World Fish Migration Day and offered this short reflection drawing on his research:
Can America's Eastern Rivers Run Silver Again?
By John Waldman
The great seasonal movements of fish, be they coveted species such as bluefin tuna and cod or prey species like menhaden, are one of the essential elements of many aquatic ecosystems. A spectacular example is the migrations between rivers and the sea by the so-called anadromous species such as salmon, shad, river herring and sturgeon. Local community events are being held today at 250 international locations to celebrate the importance of these movements and to highlight the need to protect and restore them with the first ever "World Fish Migration Day." Activities include the celebration of the removal of a dam in Japan and the inauguration of over 20 new "fishways" past dams on rivers around the globe. The theme of the day — organized by The Nature Conservancy, Wetlands International, and the Dutch Wanningen Water Consult — is "Connecting Fish, Rivers and People."
In my new book, "Running Silver: Restoring Atlantic Rivers and their Great Fish Migrations," I seek to reconnect people with the fish that once thrived in the damaged, blocked and long-depleted rivers of the East Coast.
I wrote the book in part to learn what pristine runs of migratory fish in Atlantic rivers looked like. In the writings of early colonists, there were so many salmon, shad, alewives and other species swimming upriver to spawn that the waters were said to "run silver" with these fish. And they were caught in numbers we can hardly imagine anymore — one single net haul in 1827 on the Susquehanna River was estimated to contain 15 million shad and river herring. Today, the runs of shad and river herring for a whole season on the Susquehanna and other rivers may number only in the hundreds or low thousands. Similarly, while a half million Atlantic salmon once returned to New England rivers each year, all of those runs combined totaled just 611 fish in 2013.
The devastation, over generations, of these fish migrations is a perfect example of "shifting baselines" — the phenomenon by which extraordinary losses of valuable resources take place in plain sight but largely unnoticed. It is not just the mass of fish that is lost. The vanishing of these migrations leaves glaring gaps in the ecologies of their rivers. Dams have been the chief driver of these declines.
But overfishing, pollution, the water intakes of power plants, non-native species and, in the long run, climate change are major contributors, as well.
Portents of what has transpired were evident as long ago as 1839, when Henry David Thoreau paddled on the 1839 journey that formed the basis of his book "A Week on the Concord and Merrimack Rivers." He noted how healthy waterways were already being sacrificed for the power and waste disposal needs of industry and he predicted misfortune for their migratory fish.
Thoreau makes many references to their plight, even asking rhetorically: "Who hears the fishes when they cry?"
He urges them to "keep a stiff fin then, and stem all the tides thou mayst meet."
Waldman sees the book as just step one in what he calls the "Running Silver Project." Thanks to the work of Waldman and many other scientists, conservationists and communicators, eastern migratory fishes at least have a fighting chance.
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Dot Earth Blog: On World Fish Migration Day, Recalling When America’s Rivers Ran Silver
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