MAIN DUCK ISLAND, a tiny uninhabited spot on Lake Ontario, is the field naturalist’s dream, dominated by birds and animals that are easily seen and ready to be observed in their natural environment. Despite the island’s relative distance from urban life, it has become a platform for observing the impact that pollution and waste are having on the lake. For a look at our changing environment, two biologists and a journalist made the trek to seek answers and find adventure
Early one June morning last summer, Susan Yankoo and George Wheeler steered their converted tugboat, Ducks Diver, away from a dock at the tip of Prince Edward Point, an arm of the Long Point peninsula that juts out into Lake Ontario south of Belleville.
Yankoo reflected that the water below the keel was much clearer than it had been when they started their diving charter service 30 years ago. You couldn’t see the bottom back then,” Yankoo says. “Then in the ’90s, it just cleared out. It was bizarre.”
That clarity, welcome for scuba divers, is the work of zebra mussels, part of the impacts of altered nature, alien species and human activity on the lake. Her Carleton passengers saw lots of this over the next week at their destination, Main Duck, an uninhabited 200-hectare island in the middle of the lake.
Biology professor Michael Runtz, ornithology PhD candidate Jude Girard and I, a retired journalism professor, were headed out to the island for a week-long survey of bird traffic around a possible site for a wind farm in the shallow waters.
“I guess one of the things that struck me most about the island was the human impact,” Girard recalls. “I was expecting to go somewhere remote or fairly undisturbed, but in fact, I think the whole island was affected by…invasive species, history and current human use.”
Toward the end of the two-hour trip out, we saw the island’s white shorelines, looking like sand in the hazy sun. It wasn’t sand, but zebra mussel shells, piled a metre deep, the remains of the invasive molluscs, which clog water pipes, shroud shipwrecks with their shells and have strained the formerly murky Lake Ontario waters through their gills, leaving the clarity that startled Yankoo.
As the three of us watched Duck Diver churn away from the island’s only harbour after we had unloaded our gear, it was hard to imagine we were not truly alone—there was nothing to see but the even tinier Yorkshire Island, a few hundred metres away, and water forever beyond that. But beyond view, we were surrounded by the 34 million people who live along all the Great Lakes shorelines and their activities and industries. We turned our scopes on a smudge on the southwest horizon, which turned out to be the plume from the nuclear power plant at Oswego, N.Y., one of 17 active nukes on Great Lakes shorelines.
This uninhabited real estate lies 18 kilometres off Prince Edward Point and belongs to Parks Canada, with its rules: no open fires, no overnight camping without special permission, no hunting. A two-storey federal outhouse perched above the impenetrable limestone terrain, a weather-beaten Government of Canada sign (Welcome to Main Duck) tipped toward the water, and we even had a postal code, K7L XXX. No mailbox though.
Early in the 20th century, the island served as a port for a whitefish, eel, pickerel, and lake herring fishery, not to mention smuggling. Given the absence of residents, we had been told to consider the trip “extreme remote camping” with a satellite phone as our only communication with the mainland. The caution came from Ryan Zimmerling, a former sessional lecturer in the biology department and the man who organized the trip. And he warned: “There is more poison ivy on this island than I have seen anywhere else. Waterproof hiking boots would be highly recommended.” Runtz boarded our tug unconcerned about poison ivy but thinking the island might have rare flora and fauna—he admits he was wrong. “Southern birds were not dripping from the trees. Much of the flora was not southern rarities but alien species thriving in the disturbed environment.”
There were lessons to be learned, even for an experienced field naturalist. He noted that red-breasted merganser ducklings seemed “just hatched,” while common mergansers were bigger. “This suggested a slight difference in nesting times,” a fact Runtz filed away for his ornithology course. He also wondered whether the zebra mussel shells made it hard for the island’s snapping turtles to dig nests for their eggs. We watched one trying, unsuccessfully, to dig in the hard pebbly shore right beside the dock. Runtz thought that the many dead fish and birds on the mussel-shell beach “suggested that something was terribly wrong with the health of Lake Ontario.”
On the island, we could avoid poison ivy but had to contend with what seemed to be the number two plant, dog-strangling vine. Ontario’s department of agriculture calls it “an extremely aggressive plant species…[that] has been creeping into agricultural fields and pasture lands across Ontario,” and it was a constant barrier as we struggled from campsite to shoreline, carrying scopes, binoculars, cameras, water, notebooks, GPS, two-way radios and food. Which is what we did repeatedly for a week to count gulls, cormorants, terns, ducks and any other birds that flew past offshore.
On the way out on the tug, Yankoo had filled us in a bit on the island’s history. Once it was privately owned, and “one of the owners was John Foster Dulles,” she said, poking fun at the only passenger old enough to remember U.S. president Eisenhower’s secretary of state. Before Dulles, about 70 fishing shacks lined the shore of the harbour. One wealthy resident had a stone house and a farm with racehorses, sheep, hogs, cattle, even buffalo. Decades later it’s still a favoured stop for sailors, and no wonder. The island has beauty in abundance, with dragonflies, wildflowers and weather topping the list. The meadows were alive with lobelia and harebell, a delicate wild analogue of the common garden bluebell; there were clovers not seen on the mainland, and a plant called silverweed stretched red horizontal stems across sand, rock or mussel shells to start a junior version of itself.
“It was amazing to watch the sky, to watch how the storms and clouds grow and move around,” Girard recalls. “And just when you thought a storm was moving away, it seemed to come back and the thunder and lightning and rain started.” Start it often did, testing our tents and cooking skills, but when the sun came out, the isolation seemed to boost the island’s colours. Natural surprises included a crèche of baby mergansers.
Along the shore, Girard yelled, “There’s a crèche!” and I drew a blank. A lesson for the non-scientist followed. A crèche is one or two female mergansers followed by up to 100 ducklings, paddling like mad to keep up. A flock somehow assigns adult females to take over all the merganser fledglings while the other adults are absent—an ornithological mystery.
There was mysterious geology too. The island shoreline is layers of flat, horizontal limestone. But here and there along the beach, huge granite boulders sit in the shallow water, probably dropped by glaciers thousands of years ago to be rounded by the waves and ice.
We set up our tents a few metres from the dock near an overgrown barn with its roof half caved in by a fallen willow tree. The intact side of the roof sheltered us from rain and also sheltered nests of swallows in the rafters. Inside the barn during one heavy rain, a swallow chick fell to the floor and was seized simultaneously by two snakes, a pair among the 100 or so garter snakes and northern water snakes (harmless to humans) we saw during our stay. A tug-of-war ensued, the big snake won, and mom and dad swallow had one less mouth to feed.
Unless it rained hard, with lightning (steel tripods and scopes mix poorly with lightning), we did three shifts a day at different points on the shore. We noted each bird, its flight direction, its height and its distance offshore. Girard said, “To do field biology, you’ve got to know how to count,” and the concentration needed to do it was astonishing.
It was smelly work on the south shore. Winds and waves dump tons of phosphate-rich algae there to rot, along with dead carp and gobies, victims of botulism. Both fish are alien invaders and bad news for the ecological balance, the carp having been introduced in 1879 and the goby in 1990. But still, everyone was happy. After all, we were close to the morning fly-by of Caspian terns carrying fish to their young, a few sandpipers plucking insects from algae and snakes slithering into the water.
Runtz saw these activities as signs “that the ecosystem might find a way to survive our mistreatment.”
We’ll be back. The lake won’t go away.