In 1959, two New Brunswick fishermen came up with a simple plan for 12 snowshoe hares. Wesley Ingalls and his nephew, Junior, carried the animals by boat from Grand Manan Island to nearby Hay Island in the Bay of Fundy. They hoped the hares would reproduce and give them something to trap during the winter, when they were not fishing.
Removing the hares proved much more difficult than introducing them. The trapping reduced the hare population, but it recovered within two years. Hares were very difficult to catch; they bred rapidly and could live in the thick vegetation of the island.
In 1998, Nathaniel Wheelwright, an ecologist at Bowdoin College, initiated a trapping experiment with the approval of the government of New Brunswick. Again in 2002, the same thing happened.
Wheelwright finally consulted with the vertebrate pest control officials of New Zealand, who told him that it could be done.
These observations, documented by Wheelwright in Frontiers in Ecology and the Environment , showed how strongly the introduced hares were suppressing forest regeneration. Instead, the experiment transformed the islands’ forests. The hares multiplied rapidly and crossed from Hay Island to neighboring Kent Island. The damage was more than a matter of hungry animals eating a few saplings. The hares became a powerful force shaping the ecosystem. They browsed the growing tips of young white spruce , sometimes reaching branches high above the ground. The difference helped rule out other possible explanations for the lack of forest regeneration, including the harsh climate and the Bay of Fundy’s salty fog. The hares kept young trees from surviving long enough to replace aging canopy trees. By the 1980s, storms were increasingly knocking down older trees, while few young trees were available to replace them. Forested areas began turning into open tangles dominated by plants such as wood fern and raspberry.
Research published in The Canadian Field-Naturalist found that tree recruitment on Kent Island plummeted after the 1959 introduction and remained low, while trees continued to establish on nearby hare-free Outer Wood Island. It took repeated attempts and nearly half a century before the last hare was trapped in 2007. In some areas, their droppings reached densities of about 50 per square meter. When researchers enclosed small plots so hares could not enter, seedling densities inside the protected areas eventually exceeded 150 per square meter, compared with none outside the fences.
