One of the sure signs of spring here in the Pontiac countryside is the chorus of frogs. Starting at twilight, or after a sprinkling of rain, their mating calls fill the air and banish the memory of winter.
Can you imagine a spring without such joyous song?
Hardly. Just like the honking of migrating geese, the burst of white plum and cherry blossoms, and the rush of returning songbirds, the amphibian chorus represents an integral part of our Pontiac spring.
But something is amiss in the amphibian world.
Species such as the once-common leopard frog are declining in numbers.
Why? Perhaps it is pesticide use. Perhaps it is habitat destruction. Perhaps it is global warming, which, in frog terms, is translated into ultra-violet ray sensitivity and (again) the drying of wetland habitats due to climate, not direct human intervention.
Because species are in decline, the Canadian Frogwatch Program was initiated.
I found out about it because I am a member of the Canadian Nature Federation. In the last issue of the association’s magazine, Nature Canada, I received a large, coloured Frogwatch poster. I decided to investigate the program, using the Internet. Here’s what I’ve discovered both on the poster and website.
Frogwatch is a national volunteer monitoring program that helps assess what ecological changes are occurring throughout Canada and their impact on frog populations. Scientific monitoring methods established by scientists at Environment Canada’s Ecological Monitoring and Assessment Network (EMAN) are used for the Frogwatch project.
Frogs are particularly sensitivity to habitat change. Here are some reasons why. (This list is taken from the Frogwatch poster.)
1. Life history. Frogs live on land and in water and are, therefore, particularly susceptible to changes in both habitats. From their jelly-like egg masses through to gill-breathing tadpole and finally the air-breathing adult frog, each metamorphosis, or change, is complex and exposes the creature to a variety of potentially harmful stimulae.
2. Permeable skin. Frogs keep their skin moist by absorbing water through their skin. Therefore, they are particularly susceptible to pollutants like herbicides and pesticides found in country ponds, streams and ditches.
3. UV-sensitivity. The ozone layer surrounding Earth is shrinking. This layer protects us from ultraviolet radiation and, because frogs’ eggs are in a jelly-like mass suspended in water, they are particularly prone to increased radiation.
4. Climate sensitivity. Metamorphosis from egg to tadpole to frog depends upon wetland habitat. As climate changes, drought situations put wetlands at risk, for example, drought prevents frog populations from breeding.
Herpetologists are scientists who study amphibians and reptiles. In the 1980s, they realized that amphibian populations were declining throughout the world.
This reduction was evident in both remote wilderness and populated regions. Therefore, it’s not just direct human intervention (such as draining wetlands for agricultural land) that is the problem.
Although some foreign species are now extinct (such as Costa Rica’s Golden Toad and three miniature frogs from Puerto Rico) Canadian frogs are “merely” suffering a marked decline.
So far.
For example, of the 11 frogs in Québec, the northern leopard frog is already known to be in trouble. In fact, this species, which was one of the most common in Western Canada, now is classified as endangered in British Columbia and Alberta. As early as the 1970s, herpetologists discovered that northern leopard frogs had vanished from many of their usual habitats.
Something is causing frogs and other amphibians and reptiles to die. What is it? That’s why Frogwatch is an important project. Scientists need our help in monitoring frog populations throughout Canada.
Frogs are relatively easy to identify during spring because there are not too many species at any given site. How can you tell which species are on-site? By the male’s spring mating calls. And, by visual observation.
If you want to learn how to identify the calls, use your telephone! Simply telephone 1-888-31FROGS and step your way through the numbering system. First of all you identify your province, then you get to listen to the calls of Québec’s 11 different species, like the bullfrog, green, mink, northern leopard, pickerel, wood frog and spring peeper.
Frogwatch participants should commit to monitoring a particular site for a period of years. The site could be your backyard, your farm pond, the lake at your cottage. This can be a project that your family, class, Scout or Guide troop decide to take on. You need to be able to identify the types of frogs by their sound and by their appearance. Which frogs are calling at a given site? When do they call (under what conditions, what time of day)? Are they still calling next year? (This is a particularly important question to answer and demands a long-term commitment).
Are you on the Internet? If you are, find out more about Frogwatch by clicking on the Canadian Nature Federation website and stepping through the pages you will find at www.cnf.ca
Specifically, to find out more about Québec amphibians, contact:
Quebec Amphibian Populations Monitoring Program
David Rodrigue, Co-ordinator
Saint Lawrence Valley Natural History Society
21125 ch. Ste-Marie
Ste-Anne-de-Bellevue, QC H9X 3Y7
Tel: (514) 457-9449
Fax: (514) 457-0769
E-mail: ecomus@total.net
If you are not on the Internet contact the Canadian Nature Federation, 1 Nicholas St., Ste. 606, Ottawa, ON K1N 7B7, Tel (613) 562-3447; fax (613) 562-3371; e-mail cnf@cnf.ca
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Katharine Fletcher is a freelance writer who enjoys the leopard and green frogs calling from her pond, north of Quyon. Contact her at fletcher.katharine@gmail.com