On an ordinary weekday recently, I stood beside Highway 401 near Gananoque counting cars and trucks at 9:30 in the morning, and trying to imagine what it would be like to be an animal driven by a genetic demand to wander, and wanting to cross to the other side.

There were 22 cars and transports a minute driving in the two eastbound lanes and 23 a minute in the two westbound lanes. By 4:30 in the afternoon, the numbers had doubled, and didn't revert to what they were in the morning until about 9 p.m. A few days later, I checked at three o'clock on a foggy morning, and there were still nine vehicles a minute going eastward and four a minute going westward. I'd hate to try running across anytime. It's too dangerous. But animals try. And they die trying.

Don Ross has counted the bodies. He walked along one side of the highway, down from the shoulder, along a 47-kilometre stretch from west of Gananoque eastward almost to Brockville. And then he turned around and walked back on the other side of the highway.

He was hired by the Algonquin to Adirondack Conservation Association (A2A) and some of its coalition partners to survey this stretch of highway because it cuts across a bottleneck of land where A2A is trying to preserve habitat that will connect Algonquin Park in Ontario with Adirondack Park in New York state. A2A wanted to know what animals were trying to cross the highway, how they were crossing and what improvements could be made.

It sees Highway 401 as an imposing barrier to the movement of wildlife and a challenge to its credo that "the wild and the civilized can and should coexist." Ross is the science co-ordinator for the Thousand Islands-Frontenac Arch Biosphere Reserve and is a former Parks Canada naturalist.

Ross cautions that his count is only a snapshot taken on one occasion. Nevertheless, he found 45 dead animals, apparently killed "within recent weeks."

Not surprisingly, most of the dead animals were beside the highway west of Gananoque where a concrete median divides the highway for 6.7 kilometres.

The two sides of the 6.7 kilometres with the concrete divider accounts for only 14 per cent of the stretch he surveyed, but it contained 76 per cent of the dead animals. So, the concrete barrier, combined with no immediate alternative for getting across the highway, created a wildlife killing field — and the situation is bound to get worse with plans to eventually widen the highway to six lanes.

Ross's 61-page report says that during his two-way walking tour, he found indications of widespread efforts of animals to cross the highway, some successfully through culverts and under bridges, some dying after being hit on the asphalt. There were deer, coyotes, foxes, raccoons, mink, beavers, weasels, meadow voles, muskrats, otters, turtles, groundhogs, fishers and frogs. In other studies, there are records of radio-collared moose and lynx leaving Adirondack Park and arriving in Ontario north of Highway 401.

The desire to wander is so strong, Ross says, that judging from tracks he had seen across snow and ice, deer were squeezing through culverts under the highway where the clearance is only one metre.

In his 94-kilometre roundtrip, Ross found a couple of places where animals can cross the highway safely under bridges over watercourses. And there are some rectangular culverts that serve as modest passageways. But all need upgrading, he says, and they all need better connections to habitat on both sides of the highway if they are to become effective passageways.

What also are needed are a couple of animal overpasses across the highway, and Ross points out in his report that there are rock cuts connecting good habitat on both sides of the highway where overpasses could be built at reduced cost. In Europe, and at Banff National Park in Alberta, overpasses have worked extremely well, he says.

His report is the first effort to analyze how to reunite the habitat that Highway 401 has severed. It will be especially important, Ross says, to upgrade the culverts.

"That's where the real work of biodiversity gets done. That's where the bottom of the food chain crosses over."

The report also is the first to document the extent of the slaughter of animals on the highway. That alone should raise public concern. In his tally of bodies, he found 13 dead deer. All I can say is that we're lucky there weren't also at least 13 dead motorists.