Amphibians
A chorus of male wood frogs “quacking” for potential mates is a sure sign of spring. Every year western toads and long-toed salamanders join wood frogs to breed in Maxwell Lake, often while some ice is still present.
Adults of all three species enter the shallows to court and mate. After eggs
are laid adults live in the forest up to one kilometre away from water feeding on insects and other invertebrates.
None of these species remain in the lake over the winter. In late fall salamanders and toads burrow down below the frost line for the winter. Amazingly, wood frogs are able to freeze solid and often spend the winter under logs or other ground cover. Wood frog eggs are in globular clusters, western toad eggs are in long strings and long-toed salamander eggs are singly glued to underwater vegetation. Salamander eggs are larger than frog or toad eggs.
Within 3 weeks, frog and toad eggs hatch into tadpoles and salamander eggs hatch into larvae. By August a process called metamorphosis transforms the young into adult form. These small versions of their parents then leave the water and live a terrestrial (i.e. dry ground) lifestyle. Long-toed salamanders from the same pond can look quite different and can live up to 10 years.
Did you know?
- The terrestrial habitat around Maxwell Lake is just as important for this amphibian population as the pond itself since 90% of their time is spent in the adjacent forest.
- The introduction of fish into a fishless pond can wipe out an amphibian population that uses that pond for egg laying. Fish will eat the eggs, tadpoles, and larvae.
- Many amphibians world-wide are declining, often for unknown reasons. Some theories include pesticide/herbicides, global warming, UV radiation, acid rain, habitat loss, or disease. Alberta is not immune to these declines. Leopard frogs occurred throughout much of the province in the 1970s and now are only found in a small area of Southeast Alberta.