By GLENN GARNETT
Nearly forty years ago, famed biologist and author Rachel Carson warned of a silent spring, when the impact of pesticides and other chemicals would one day destroy the lower links of the food chain. It’s hard to imagine an evening on the dock without hearing croaking toads and frogs - but the risk remains at the dawn of a new century.
That’s because amphibians of all kinds are disappearing. A change in global environment is one reason but the disappearance of habitat is a major contributing factor. The Toronto Zoo points out that over 80% of southern Ontario’s wetlands have been destroyed due to drainage for agriculture or for urban development. This wetland crisis is not unique to Ontario, and frogs are not the only species threatened.
A quick check of the Internet reveals movements across the globe to protect disappearing and frog and toad species - in South America, Africa and Australia as well as North America.
Nancy Hickinbottom, volunteer with Toronto’s zoo, is among many trying to drum up interest and concern in protecting pad-dwellers.
"Frogs are definitely decreasing in number, and they’re very often an indicator of damage to the environment, whether it’s the reduction in ozone, increased acid rain or use of pesticides," Hickinbottom says. "Their skin is so thin it’s very vulnerable, and as we lose more frogs, it serves as a warning that other species may also be in danger."
She says there’s a lot of things cottagers can do to help arrest this decline.
"Some of it involves being a little more careful of what you do," she says. "For example, some use frogs for bait. It’s better to purchase them from farms that raise frogs expressly for that purpose and not taken from the wild."
Hickinbottom also urges cottages not to pave their driveways - for an interesting reason.
"Frogs will often breed in those tire ruts that hold water," she explains. "They lay their eggs in them because the water warms up fast, the eggs hatch quickly and the tadpoles go through their growth stages quickly before heading out to the water.
"Many people when they get to their cottages in the spring find these ruts and do something about them," she says. "But if you can hang in there until late spring or early summer when they’re dried up, then level it off with gravel, that will go a long way to supporting the growth of your local frog population."
Of course, Hickinbottom also suggests cottagers think twice before clearing wetland areas on their property.
There’s more you do to help frogs, and it has to do with keeping your eyes - and ears - open.
"We have a ‘Frogwatch’ program in Ontario in which people are identifying what they see, how many and where, and report to an online site," she explains, adding the purpose of the program is to increase our knowledge of frogs and toads in the province.
Participants are asked to monitor frog and toad "calls" so scientists will be able to track the annual south-to-north progression of these calls with warmer spring temperatures, and monitor the effect of this climate change over longer periods of time. And by tracking population, they can determine the impact of environmental stresses.
Male frogs and toads call to lure the ladies and to ward off males elbowing into their soggy turf. According to the Frogwatch website, some species call as early as March and others as late as August and each frog and toad species has its own distinct call. Spring peepers, wood frogs, and chorus frogs are usually the first species to make their presence known in the spring, but larger frogs like the bullfrog may call as late as June or July.
The Frogwatch program kicked off this year in March with participants listening for frog and toad calls in their local wetlands as the critters emerged from their winter hibernation. Frogwatchers can call a hotline number toll at 1-888-31FROGS to help them recognize Ontario's 13 species of frogs and toads. Armed with that knowledge, they are then able to track local populations and post their findings on a website. The database is linked to interactive maps to display your findings.
The information then goes to the database at the Natural Heritage Information Centre in Peterborough, and all this material is put into a long-term database, used by researchers for distribution patterns of the different frog and toad species in Ontario and Canada.
Check out the Frogwatch Ontario website at:
Rachel Carson believed that paying attention to the welfare of smaller species paid off big. She once wrote: "The more clearly we can focus our attention on the wonders and realities of the universe about us, the less taste we shall have for destruction."