- TOP PLAYERSOffensePABLO S. TORRE | August 20, 2012
- TAMPA BAY buccaneersENEMY lines WHAT A RIVAL COACH SAYSJune 28, 2012
- Faces in the CrowdJune 11, 2001
A newly created kind of trout is swimming in Canadian water this summer. It is an eager, handsome fish, fast-growing and with a roving eye for food. This trout, first called a splake and recently renamed wendigo, is the fulfillment of a dream nurtured for more than half a century by aquatic biologists, for it is a successful cross, or hybrid. Fish crosses occur rarely in nature and the progeny of such a mating between separate species (usually of the same family) is likely to be infertile. But the wendigo trout can reproduce itself. It is here to stay
It took an ingenious Canadian game warden named James E. Stenton, whose bailiwick for the past 19 years has been the Lake Minnewanka District of Banff National Park in Alberta, to achieve this biologic miracle. Stenton, a keen naturalist as well as a warden, crossed a female lake trout with a male brook trout in a homemade hatchery he constructed in an abandoned tunnel under a dam. Daily Stenton examined the precious eggs lying in wooden troughs in the chill dark. Finally they "eyed," meaning they had been fertilized and—at length—the tiny orange jewels hatched.
To fully appreciate this feat one must take a brief look at the history of trying to create trout hybrids. In 1880 R. B. Roosevelt reported that he had tried to mate male brook trout with West Coast salmon. The resulting hybrids were all females and when he attempted to strip them of their eggs for artificial fertilization he found them too large to pass through the vents. He thereupon resorted to surgery and exposed the eggs to the milt of normal male trout. Not an egg became fertilized.
In 1887 Francis Day claimed he obtained hybrids by crossing Atlantic salmon, trout and char, and Tarleton Bean in 1889 reported surviving specimens of brook-rainbow-and brook-lake-trout crosses. In 1906 J. A. Richardson, experimenting in Karluk, Alaska, obtained astonishing results when he attempted to cross the five species of Pacific salmon. He had well-formed fry from the union of the dog and humpback salmon, but the hybrids of the dog and king salmon had long pointed noses and were eyeless.
Stenton learned that some biologists had been on the verge of success, at least as far as the brook-lake-trout cross was concerned, but had never continued their experiments, dropping them without explanation. This intrigued and annoyed him.
The lake trout in Minnewanka were Stenton's primary responsibility. Since 1940, when a new dam was erected at the lake, part of his job was to make a yearly census of the lakers by means of gill nets to determine the effect of the 65-foot change in water level on the fish population. In 1945, after completing that season's census, Stenton stopped and considered. Every year he had an abundance of lake trout at his fingertips. All he needed were the brook trout and he could perform his own experimenting.
In the fall of the following year, 1946, he dipped his nets into the Vermilion Lakes near the town of Banff and hauled in a supply of brook trout. Then he dipped into Minnewanka for his lakers. He stripped the fish of eggs and milt and tried two crosses: the male brook with the female laker, and the female brook with the male laker. Then his problem was to find some place where he could rear his charges.
The Banff Hatchery wouldn't do; that year the town was experimenting with the chlorination of its drinking water which also supplied the hatchery pools. If the eggs died in this environment, his experiment would prove nothing except that his fish couldn't survive the chlorine. He needed dark incubating troughs with plenty of pure running water which wouldn't freeze in Alberta's 50-below-zero winter weather.
Beneath the Minnewanka Dam was a tunnel which extended far under the lake, and through it ran a wood-stave pipe which supplied water during the forest-fire season to the Cascade River, now dried up by the new construction. This tunnel became Stenton's hatchery. The head of water maintained in the pipe through the winter fed his two homemade rearing troughs. Since this water came from 55 feet below the surface of the ice-covered lake, its temperature never dropped below 38� Fahrenheit and remained constant all winter.
Stenton tended his offspring daily by flashlight. He saw the eggs of the female brook trout, which had been fertilized by milt from the male lake trout, burst and die; they were too small for the large embryos. But those of the other cross remained healthy and grew.