Species at risk are plants and animals that may be lost forever if we don’t act soon.
Our monthly Species at Risk Series explores which ones are found in the Ottawa Valley and what we can do to protect them.
Did you know there are two species of chorus frog in the Ottawa Valley: the western and the boreal chorus frog?
This month, we’re focusing on the western chorus frog, otherwise known as Pseudacris triseriata.
This species is listed as threatened in our region.
What does the western chorus frog look like?
This amphibian is about 2.5 to 4 cm in length and weighs less than a pound. Its body is smooth and pear-shaped with a narrow, pointed head and very long toes with small toe-pads.
The western chorus frog can vary from green-gray to brown, though it’s distinguishable by the three dark stripes down its back and a white stripe along its upper lip.
Male western chorus frogs have a vocal sac, which looks like a dark flap when relaxed but will turn yellow once expanded.
What do they sound like?
During breeding season, this frog’s call resembles the noise of fingernails running along the teeth of a metal comb.
During good weather conditions, the call can be heard nearly a kilometre away.
How are they born?
Western chorus frogs breed in the spring, with mating calls beginning as early as mid-March.
Females will lay their eggs on vegetation, which hatch within a few weeks. Tadpoles typically finish transforming by midsummer and mature within one year.
Where do western chorus frogs live?
This amphibian is found across the Ottawa Valley in southern Ontario and southwestern Quebec.
Specifically in Ontario, its range stems from Georgian Bay to the northwest to Algonquin Park to the south and the Ottawa River near Eganville to the east. In Quebec, you’ll find this small frog in the Outaouais and Montérégie regions.
The western chorus frog is a lowland terrestrial species, meaning it can be found on marshes, wooded wetlands, ponds, swamps, or near damp meadows.
What threatens the Western chorus frog?
This species has declined in Quebec by about 37% per decade since the 1950s.
From 1995 to 2006, the population decline is slower by about 3.5% per year, or a total decrease of approximately 30%.
Land use is the main threat to the western chorus frog.
In southwestern Quebec, habitat destruction in suburban areas is so rampant it’s estimated this species will become extirpated from their known habitats within a decade.
Habitat loss and fragmentation due to agricultural practices can also result in decreased populations, as seen in Quebec between 1950 and 1990.
What can you do to help?
Maintain wetlands, shorelines, and forested areas in their natural state on your property. Avoid removing large trees, woody debris, and rock piles as they can serve as habitat for many reptiles and amphibians. If you have the space to create a small artificial pond, these are very beneficial for many species.
In your community, follow development applications and proposals to develop low-lying forests and open areas where western chorus frogs may be present and provide input to decision-makers.
If you see a western chorus frog, document its location, take photos, and share the data with your province’s department responsible for the protection of species at risk.
Finally, educate your neighbours of the important role played by reptiles and amphibians in maintaining healthy ecosystems and of the value of wetlands and forests in your community.