Dawson Trail Dispatch, written by Norm Gregoire, April 2025
Page 17 https://issuu.com/dispatch222/docs/dawson_trail_dispatch_april_2025
April brings new life to the tall-grass prairie. This is most obviously observed by witnessing the budding of trees and the arrival of migrating birds. This is also the time when winter’s dormant creatures start to make it known that they are out and about. With a ribbit, ribbit, croak, croak, amphibians are announcing they are awake and active! There are sixteen different amphibians that can be found in Manitoba, including eight frogs, four toads, and four salamanders; many of them live in the tall-grass prairie.
Amphibians are cold-blooded vertebrates who start their lives as an egg, followed by an aquatic, gill-breathing larval stage and finally growing into (usually) a terrestrial, lung-breathing adult. Another unique characteristic is that amphibians can breathe through their skin.
At this time of year, the first calls we hear are usually from spring peepers, wood frogs, and boreal chorus frogs. These boisterous calls are mostly used to attract a mate. After mating, hundreds to thousands of eggs are laid depending on the species. This is always done in water on vegetation or debris. The eggs will hatch within a few days, and the larval/juvenile stage takes a few weeks to a few months to grow into an adult. Some salamanders occasionally take years to fully develop into a mature adult, and some will not grow past the larval stage but still gain the ability to mate. This is known as neoteny.
Not that we want to be thinking about winter already, but amphibians have some amazing adaptations to get them through the freezing temperatures. Wood, spring peeper, boreal chorus, and (Cope’s) gray tree frogs survive by allowing themselves to freeze over winter. Their internal organs and metabolic activity slow down almost completely. The wood frog is especially known for their winter survival strategy of creating their own antifreeze, which keeps dehydration from completely happening on a cellular level. When warmer weather arrives, the frogs will thaw out as if nothing had happened. Toads will dig deep into the ground and rely on that cover as insulation to wait out the winter, whereas salamanders rely on holes dug by other animals or natural structure to hide where frost can’t reach. Mudpuppies are a unique Manitoban amphibian due to the adult keeping its gills all its life and never leaving the water. Even in the winter, mudpuppies are active.
Globally, amphibian biodiversity is in decline. The specifics of this decline vary from species to species; however, habitat loss or degradation is usually a key factor. As previously mentioned, amphibians rely on both aquatic and terrestrial habitats at varying stages of their life cycle. This need for both habitats increases the number of threats caused by an unhealthy, fragmented ecosystem. Amphibians permeable skin means they are especially affected by pollution and chemical contact. The emergence of chytridiomycosis (a fungal disease) is of major concern to amphibians, mainly in the southern hemisphere. Although some of these threats seem distant, the tall-grass prairie is home to two amphibian species at risk: the eastern tiger salamander and the northern leopard frog.
Adventures with Nature Norm
Amphibians are a unique family of animals, and we are fortunate to have a great diversity of them in the tall-grass prairie. If you are interested in learning more about these amazing creatures, please join the next Adventures with Nature Norm on April 26th, 10am-12pm, at the Weston Family Tall Grass Prairie Interpretive Centre for an interpretive walk followed by an indoor presentation. For more information, please contact Norm at info@sharedlegacymb.ca.
Eastern Tiger Salamander