Two U.S. Fish & Wildlife fisheries staffers visited Western New York waterways last week and did some extensive surveys of stream waters, searching for ammocetes, the early-stage larvae of sea lamprey, a dreaded aquatic invader.
Biologist Dave Keffer and biology sciences technician Ed LaFuente surveyed for sea lamprey larvae mainly in Cattaraugus Creek and found samples of these aquatic intruders at all five sites in Seneca Nation of Indians waters as well the mouth of the waterway.
Keffer and LaFuente strap battery packs and electro-shocking units on their backs and work positive and negative strainer-like wands along mud-bottomed shallows in search of larvae that stage for one to three years in silted areas of streams. The process looks something like an outer space adventure; for Keffer, it approximates that.
“I’ve been doing this for 23 years, and every day is a discovery and an adventure,” he said while packing up for another survey below the Aldrich Street bridge in Gowanda. He and LaFuente stirred up only a few crayfish while working ideally clear, mud-coated bottoms of shallow Thatcher Brook on Tuesday afternoon.
Earlier, Keefer and LaFuente had collected and preserved live samples of all three year-stages of ammocetes. “The third-year stages are ones that got away from the 2011 lampricide treatment in the ‘Catt,'” Keffer explained.
With nearly 30 miles of main stream and many feeder streams along the way, Cattaraugus Creek provides good breeding grounds for these creatures. “Adults can move in and spawn in the upstream gravel and the larvae can then inhabit muddy silt in these back waters,” Keffer noted as they checked areas around the bridge and brook.
They usually reach their adult stage in three years, but Keffer said they have been know to last 17 years before emerging as an adult predator.
Their history goes back to well before Greek Empire times, long before they entered Great Lakes waters. The Greek/scientific name for sea lampreys translates to “stone sucker,” because while spawning in shallow Grecian waters they were often seen moving large stones to form a nesting area.
Sea lampreys were first detected in Lake Ontario in 1835, entering through the St. Lawrence River. Niagara Falls barred their access to Lake Erie; these fin-less, boneless, eel-like creatures need gentle currents and open waters to make their way upstream to find prey and to spawn.
They began finding Lake Erie prey when Welland Canal upgrades deepened the canal in 1913. By 1919, these blood and body fluid-suckers from Lake Ontario had moved through the canal and were being found on Erie game fish, mainly lake trout.
Wounds inflicted during the year-long adult stage of a mature sea lamprey kill an average of about 40 pounds of adult trout, salmon or other fish species to which they attach and remove blood and fluids.
By the early 1950’s, declining fish numbers, for commercial and recreational fishermen, were drastic and sea lamprey numbers steadily increased. Fishery concerns along the Great Lakes chain generate about $7 billion for the economy annually.
A Great Lake Fishery Commission was formed in 1955 and includes all adjacent U.S. states and Ontario. Among other goals/tasks, controlling and reducing sea lamprey numbers was and continues to be a major area of concern.
“We know we can’t eradicate them, but we always strive to control them,” Keffer said of the process that has used the lampricide TFM (trifluoromethyl) to kill adult-stage sea lampreys since its introduction in 1958.
Keffer worked the 1994 TFM application in Cattaraugus Creek and for 23 years has monitored this and many of the other 400 known Great Lakes feeder-stream areas where sea lamprey can propagate.
LaFuente noted that part of the problem is their travels as adults. Telemetry studies have shown see lampreys can move long distances. While no proof could be discovered in Western New York waters, there is a possibility that some adults may have arrived here from the Detroit River.
Each year, sea lampreys appear in different places. Keefer got a report from an angler who saw them in Big Sister Creek. “We surveyed the creek and found them there for the first time,” he said of an additional survey added while working Buffalo River, Cazenovia Creek and Cayuga Creek earlier this year.
From all indications, Keffer believes Cattaraugus Creek will be scheduled for a complete lampricide treatment in 2015, but that effort will not be confirmed until after additional surveys are conducted in September.
If you fish the Cattaraugus this fall and see spacemen-like waders with large backpacks working two long skimmer poles along creek bottoms, it is not an alien invasion. They will be trained personnel seeking out alien aquatic invaders that need to be kept in check.