In fact, lakeOntario has been changing for 200 years, ever since the War of 1812 made the Great Lakes’ shores safe for American settlers, who moved here in droves. Back then, the lake held the world’s largest landlocked population of Atlantic salmon, so many that people could wade into the water and pitchfork them onto shore. But the settlers threw milldams up across major tributaries, which kept the salmon from their spawning grounds, and cut down trees, causing the wetland to dry up. By 1860, the salmon were gone.
In the 20th century, untreated sewage and wastewater, phosphate-rich runoff from farms, DDT, PCBs, mercury, dioxin, cadmium and other pesticides, herbicides and industrial wastes began to enter the lakes. Small organisms such as plankton take DDT and other toxins into their systems and pass them up the food chain. In the 1960s, scientists found DDT concentrations in fish-eating birds one million times the amount in the water. The high levels of DDT caused birds to lay eggs with eggshells too thin to support the weight of incubating adults. From the late 1950s to the early 1970s, cormorants, bald eagles, osprey and other fisheaters in the area had little success reproducing. Pretty soon the birds were almost gone.
Into this situation swam a little plankton-eating baitfish called an alewife, which found an ideal habitat in the plankton-rich, nearly predator-free waters of LakeOntario. The tiny fish prospered. By the 1950s, so many alewives would wash up onshore they had to be cleared away with backhoes. This abundance led DEC fisheries biologists to conclude that the lake could support some new sport fish species to boost the local economy and reduce nuisance levels of alewifes. In 1968, they began stocking the lake with Pacific salmon—chinook and coho—and a kind of char known as lake trout. Anglers from all over the world came to towns like Henderson to catch them. In 1988, visitors spent more than $34 million on fishing and fishing-related activities in JeffersonCounty, which includes Henderson. This despite DEC fishing regulations warning anglers that the larger salmon and lake trout are so heavily contaminated with toxins they shouldn’t be eaten more than once a month. (Brown trout over 20 inches, lake trout over 25 inches and all Chinook salmon and carp are too contaminated to eat.)
As DEC biologists started stocking fish, events outside the state were beginning to exert profound changes on the Great Lakes. In 1972, DDT was banned nationwide, a response in large part to the publication of Rachel Carson’s Silent Spring in 1962. In 1969, the oily waters of Ohio’s CuyahogaRiver caught fire and burned; towering flames reached five-stories high and helped trigger passage, in 1972, of the Clean Water Act. The results were dramatic: by the mid-’70s, Lake Ontario had cleared up so much that the eggs of fish-eating birds had begun to hatch once again.
Enter the cormorant, a sinuous dark bird with the vulturine habit of perching with wings outstretched, feathers like laundry hung on a line to dry. (In fact, it spreads its wings to dry them; the cormorant’s feathers lack the waterproofing of many other waterbirds, an adaptation thought to enhance performance when it dives for fish.) Humans have long recognized the comorant’s fishing prowess: some 1,300 years ago, the Japanese perfected ukai, a method of river fishing using cormorants on leashes. A small metal ring fitted around the neck of each cormorant prevents it from swallowing the fish it captures. That same fishing skill had earned cormorants the enmity of fishermen long before the incident at Little Galloo. Environmentalist Farley Mowat noted in 1984 that Canadian fishermen at the turn of the 20th century blamed the cormorant for declining fish stocks in the Great Lakes. “This led to a deliberate attempt to wipe them out,” he wrote in Sea of Slaughter, “chiefly by raids on their rookeries during which all eggs and chicks would be ground under foot and as many adults as possible shot down.” This campaign proved so successful, he wrote, that “by 1940, fewer than 3,000 great cormorants existed in Canadian waters.”