Print | Bookmark

Are Frogs Disappearing?

In many parts of the world, there is a suspicion that frogs are not as common as people remember them to be. Some species have not been seen for decades. Range reductions, population decline and extinction are difficult to prove for many reasons - lack of good data from past years, normal yearly variations in climate, normal population fluctuations, differences in the effort put into looking for frogs, problems with accurate identification. But the suspicion remains strong and is being actively researched, so that firm statements of population decline can now be made for some species in some parts of the world. Other species seem to be stable.

Worldwide, the destruction of wetlands, breeding habitats for frogs, is the major threat. On the other hand, some highway construction may create roadside ponds which are good breeding sites for some Nova Scotia species. Some roads, with concrete dividers, are barriers to migration. And death by rubber tire while crossing wet highways is common in Nova Scotia.

Frogs, and all amphibians, may be sensitive indicators of water quality because they absorb gases and chemicals directly through the skin. Vanishing frogs could be an early warning of serious water problems in the environment.

The issue is important enough that a worldwide group of scientists, the Declining Amphibian Populations Task Force (DAPTF), has formed to share research results and spread the word. FROGLOG is the newsletter of the World Conservation Union, Species Survival Commission, Declining Amphibians Populations Task Force.

The Canadian working group, DAPCAN, has an annual conference and a newsletter, the Boreal Dip Net (not on-line as far as we know).

You can check Environment Canada's Greenlane site, there may be current information posted about wetlands, habitat loss and amphibians in the Great Lakes basin.

Nova Scotia's Frogwatch program is designed to raise public awareness and gather provincial data about breeding locations and breeding times of the Northern Spring Peeper. This program won a Nova Scotia Environmental Award in 1995 and a national award for best museum program in Canada in 1996.