Concern for wildlife is usually about declining numbers. But snow geese in Northern Ontario are attracting a lot of attention these days because there might be too many of them.

In fact, since the 1970s, the population explosion of lesser snow geese in the James Bay and Hudson Bay area appears to have caused extensive damage to vegetation, and reduced some areas of coastal salt marshes to a desert-like landscape. Concern about this rapid and major decline of the coastal environment was the motivation behind a long-term, large-scale study called the Hudson Bay Project, begun in 1993.

"The Hudson Bay Project is a joint effort of scientists and organizations in Canada and the United States," says Ken Abraham, wildlife research biologist at the Ontario Ministry of Natural Resources. "Our main purpose is to study the effects of a very high population of snow geese on the ecosystem of the Hudson Bay and James Bay coastal areas of Northern Ontario and Manitoba."

The Hudson Bay Project team is made up of three MNR scientists; two professors from the department of botany of the University of Toronto; one professor from City University of New York and the American Museum of Natural History; and one climatologist from Environment Canada.

"We started the project in 1993 but its roots go back to the 1970s and the early collaboration between Ken Abraham, Robert Rockwell of the American Museum of Natural History in New York, and myself," says Robert Jefferies of the department of botany at the University of Toronto.

In the early 1980s, to study the environmental effects of goose feeding and defecating, Jefferies fenced off small patches of ground for future comparison with surrounding areas where geese roam freely. Today, those areas of protected vegetation appear as lush, green islands in an otherwise barren landscape largely devoid of vegetation.

A number of factors may have contributed to the dramatic increase in the snow goose population. Snow geese now feed mostly on agricultural waste grains and green plants for a large part of the time they spend away from the north. This change in their traditional food source has boosted their survival and overall well-being, and in turn led to changes in where the birds nest and live. As well, migration routes can shift over time and result in changes in how the birds are distributed over immense areas.

Recently, the project team discovered that the snow goose population has its downs as well as ups. In contrast with the tremendous increase in the entire snow goose population over the past two decades, the numbers appear to have greatly decreased in some areas, such as southern James Bay during the fall migration.

"This decrease in one area could be explained in a number of ways," says Jim Leafloor, MNR biologist in Cochrane. "It could be due to local loss of vegetation, fluctuations in the Moose River, climate changes, or changes in the timing of nesting and migration."

To keep tabs on the rise and fall of snow goose populations, the Hudson Bay Project team conducts plane and satellite surveys, as well as ground-level nest counts and habitat analysis. The team also uses information from the U.S. Fish and Wildlife Service and the Canadian Wildlife Service, the umbrella organizations responsible for monitoring migratory waterfowl.

The project also employs many students from a number of Canadian and U.S. universities, and it benefits from contributors from as far away as Denmark, as well as Saskatchewan, Wisconsin and Massachusetts. Information on the project, including a list of collaborators, contributors, and field photographs, can be found at http://research.amnh.org/~rfr/hbp/main.html.

As for the future, Abraham and his colleagues fully expect the project will continue into the new millennium. They'll keep looking for answers that will help Ontario better manage the effects of multitudes of snow geese on the fragile northern environment.

"We'll keep at it for at least the next five years," says Abraham. "We'll gather new information and try to confirm existing data, until we have a more complete understanding of why the lesser snow goose has increased so dramatically in numbers and its habitat changed so much over the past two decades."