For the last several years I have noticed few quiet, little toads hopping about devouring garden pests. In our region the spadefoot toad (Scaphiopks
holbrooki) eats beetles, crickets, spiders and other small insects and worms. The American toad (Bufo americanus) can consume 86 flies in 10 minutes, several thousand insects in a month, and 2000 cutworms in a summer. Slugs and snails are on their menu as well as mayflies,
midges, gnats and mosquitoes.
All amphibians like toads need wet places to maintain body moisture, since they breathe partly through their skin. When marsh or wetland areas are filled in for people to build housing developments and malls, toads and frogs experience a
shortage of environment.
Toads have an amazing ability to cope with adverse conditions. In summer they burrow underground to avoid extreme heat (aestivation), and in winter they can survive several weeks with two-thirds of their bodies frozen. They thaw out and
begin feeding on insects. Because of these talents to adapt, scientists disagree about methods of counting and years necessary to verify declining numbers.
This column includes highlights of some studies obtained from the Internet. The Minnesota Department of Natural Resources has concluded that the disappearance of frogs and toads can indicate serious problems in the environment. Because
amphibians exist in the water and on land, they are susceptible to all kinds of pollution. The Minnesota Frog Watch considers them an integral part of the food chain and coordinates a counting program while keeping records of deformities.
Scientists in California agree that pesticides and pollution may be factors in decreasing amphibian numbers and add other reasons: increasing ultra-violet radiation resulting from ozone depletion and global climate change.
No one underestimates the importance of urban sprawl but since the late 1970ís herpetologists have noticed changes in populations even in remote natural habitats in South America and parts of the western United States and Canada.
A number of scientists who argued that studies need to be over longer periods now realize that some species have already become extinct. The trend is unmistakable. Even in relatively unspoiled areas frogs and toads appear to be declining.
Last year the Gettysburg Times (July 4, 2000) carried a story from the Greensburg Tribune-Review titled "Scientists and Volunteers Count Frogs." In it Robb Frederick states that fear of some frog extinctions had surfaced in a herpology
conference in England in 1989.
The North American Amphibian Monitoring Program, coordinated by Linda Weir of Maryland, began their field surveys in 1995 and now has volunteers in 28 states. Weir relies on state directors like Art Hulse, biology professor at Indiana
University of Pennsylvania to recruit and train volunteers.
While scientists claim there is no real distinction (both are amphibians), I refer to the toad as invaluable warriors against plant pests in the garden. All are vulnerable to chemical fertilizers, pesticides, ozone depletion, and problems
brought about by urban sprawl.
Unfortunately, whatever the cause of the scarcity, I suspect many gardeners are looking for their quiet little helpers.
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