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FrogWatch participants of all ages can help scientists monitor Canada's frog populations.
All you have to do is listen to frogs calling at a pond — or even at the cottage or in your back yard — on a number of evenings over the calling season, record your findings, and submit the results to your provincial or territorial FrogWatch coordinator.
Changes observed in amphibians have often been seen as an indicator of changes in ecosystems because of their semi-permeable skin, which makes them particularly susceptible to changes in their environment.
Frogs are particularly valuable species to observe because they live on land and water and can signal change in both ecosystems.
Frogs and toads are disappearing, along with salamanders, newts, and the unusual caecilians. Older than the dinosaurs, recent studies show that almost one-third of all known amphibian species (and there are over 6,000 of them!) are faced with the possibility of extinction, while 120 species are thought to have gone extinct in recent decades.
No other class of organisms – birds, mammals, or plants – has faced such a high risk of widespread extinction.
Habitat loss and fragmentation
The oldest and leading cause of amphibian declines throughout the world is habitat loss. Fortunately, amphibian populations decline slowly in response to habitat change, giving people the opportunity to implement measures that would counteract this threat, such as creating protected areas.
Chemical pollutants
Chemical pollutants from agriculture and mining, as well as from human consumption of pharmaceuticals, can have a direct impact on these sensitive and semi-permeable creatures. Chemical pollution has been associated with amphibian malformations, implicated in changing the gender balance of populations, and changing water quality so that the water is inhospitable to amphibian life. You can protect the water quality in your home – easy tips for your family.
Invasive species
Aquatic habitats are often manipulated to improve their appeal and usefulness to humans. Sport fish are added to streams that feed directly on the eggs and tadpoles of native amphibians. New predators are introduced that wreak havoc on ecosystems. Invasive species do not always stem from distant countries. For example, the massive American bullfrog eats everything in its path, including native frogs in all life stages. Although American bullfrogs are native to the Eastern U.S., they have become a major problem in the West.
Disease
A mysterious fungus, Batrachochytrium dendrobatidis (“Bd”), is the culprit behind both current and historic dramatic and rapid amphibian population declines in many parts of the world, including “pristine” mountain areas. Described in both wild and captive populations in the late 1990’s, the Bd fungus thickens keratinized areas of amphibians, such as the mouthparts of tadpoles and the keratin in the skin of adults, preventing the healthy transfer of oxygen and other gases across amphibians’ skin. While more species are affected by habitat loss than Bd, the disease causes sudden and dramatic population declines that can lead to rapid extinction.
Unfortunately, at this time, the Bd fungus cannot be controlled or stopped in the wild, although affected individuals can be cured of the infection when brought in from the wild.
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