Recovering Atlantic Coast Migratory Fish Populations
Today we have a guest blog from Dr. R. Wilson Laney, Senior Biologist in Fisheries and Ecological Services with the U.S. Fish and Wildlife Service in Raleigh, North Carolina. In Celebration of World Fish Migration Day on May 24, Dr. Laney discusses the need to recover migratory fish species in the U.S.
I prefer to think of my colleagues who are and have been working hard to recover migratory fish populations along the Atlantic Coast to their historic population levels (or as close as we can given current habitat conditions), as a big family comprised of: faculty, staff, undergraduates and graduate students; federal and state natural resource management agency staff (including me) who manage fish and their habitats; staff and members of multiple fishery management institutions who develop and implement management policies; federal and state natural resources law enforcement staff; legislators at both federal and state levels who develop and pass laws benefitting fish and their habitats; judges, their staffs, and attorneys who litigate over migratory fish and their regulation; staff and members of environmental non-governmental organizations; people who catch fish (both commercially and recreationally) and/or who deal in fish, and their affiliated organizations; people who enjoy fish-watching; consumers who purchase and eat fish; restaurant owners and chefs who prepare fish for consumption; people who like to celebrate the arrival of fish on the spawning grounds; and authors who like to write about migratory fish.
This big, human, fish-loving family seeks to recover the unique and complex assemblage of migratory fishes. The human family has to be big— very big— because migratory fishes don’t spend their entire lives in only one place. They move around quite a bit, covering a lot of habitat area and long distances. The human family HAS TO WORK TOGETHER, because none of us or our organizations alone have the resources needed to achieve full restoration of all the migratory fish populations. Many of the migratory fish family members are completely or mostly ocean dwellers (e.g., tunas, billfishes, and big sharks such as the Great White). Others are nearshore and make seasonal migrations to tidal areas, estuaries, or rivers. A special sub-set of them, the ones with which I most often work, are inextricably linked to inland rivers, and are termed “diadromous.”
Diadromous means they spend their lives in two habitats— partially in the ocean and partially in freshwater. The diadromous migratory fish are of most interest to me in part because their complex life cycles pose great challenges for their collaborative management, and in part because they swim near to where I live in North Carolina, in the Neuse River Basin. There are probably American Eels swimming in the West Prong of Beaverdam Creek, which begins its flows a half-block from my house. The eels in the creek were spawned and hatched in the middle of the Atlantic Ocean, in the Sargasso Sea. They grew into larvae drifting with ocean currents; then changed to glass eels as they moved inshore; then into miniature eels called elvers; then into yellow eels; and finally will change again for the last time into silver eels to make their spawning migration back to the Sargasso Sea. And this is only ONE of the multiple diadromous species in my home watershed, the Neuse.
I have spent over a third of my life working to restore the diadromous fish family on the East Coast. Much of that time has been spent sitting in hotel conference rooms or ballrooms in meetings of the Federal Fishery Management Councils and Atlantic States Marine Fisheries Commission (ASMFC). Another significant fraction of my time has been spent writing about fish or how to manage them, as I’m doing now. Occasionally, I have managed to sneak away during the winter to a federal research vessel in the Atlantic Ocean off the North Carolina and Virginia capes. These adventures allowed an opportunity to tag migratory fishes, and listen to the cries of the seabirds as they dive-bomb the fish escaping from our nets and hear as well the chuffing of the large whales swimming past.
So why am I and many others so passionate and dedicated regarding these amazing migratory fish? The answer is because we have lost so much of their former value to society— not just their financial value as food fish, but also the value of the ecosystem services they provide— and we want to see these values restored for our children, grandchildren, and future generations. Author Sandy Burke put restoration aesthetically one way when she titled her book, Let the Rivers Run Silver Again, referring to American Shad in the Potomac River, which have been so much a part of the landscape and our culture along the entire East Coast.
Other scientist-authors have focused on the ecological dimension of migratory animals in general and diadromous migratory fish in particular. Silke Bauer and B.J. Hoye recently wrote Migratory Animals Couple Biodiversity and Ecosystem Functioning Worldwide in which they state that, “…the influence of migrants and their service on these communities is often overlooked, and as a consequence of global changes, migrations are threatened worldwide.” Karin Limburg and John Waldman noted the Dramatic Declines in North Atlantic Diadromous Fishes [PDF] on both sides of the Atlantic Ocean and their review documented that, “…all species had suffered population extirpations, and many species are now classified as threatened or endangered.” The authors conclude that the consequence of these changes is lost ecosystem services. Carolyn Hall, Adrian Jordaan, and Michael Frisk addressed Centuries of Anadromous Forage Fish Loss: Consequences for Ecosystem Connectivity and Productivity. They concluded that the, “Lost biomass of anadromous forage species resulting from the seventeenth to nineteenth century damming of waterways and from overharvest in the northeastern United States contributed to significant changes in coastal marine-terrestrial ecosystems.” They estimated the loss of anadromous forage fish increased from 10 million fish per year in 1700, to 1.4 billion fish annually by 1850.
I could go on and on, but blog pieces are supposed to be relatively short, and this one is already way longer than requested. So I’ll end with an admonishment, and a challenge. If you live in a watershed which hosted diadromous species in the past (and most all of them on the East and West Coasts did so), talk to your local fisheries agency professional and find out which species are still present, or not, and determine their present population status. The challenge is to then GET INVOLVED in restoring their habitats and their populations. There are many ways for you to do so, by participating in local efforts to restore their habitats or by directly participating, especially if you are an angler, in the fishery management process.
Visit ASMFC, GSMFC (Gulf States Marine Fisheries Commission), and PSMFC (Pacific States Marine Fisheries Commission) and read about diadromous species, listen to the management board meetings, and know who your commissioners are. Help in every way you can to see that your local river “runs silver again” in the future!