Dramatic and abrupt declines in northern leopard frog populations starting in the late 1970s resulted in extirpation of this species from large portions of its historic range in western North America. This includes much of the Waterton Biosphere Reserve (WBR) where the frog was historically present along major rivers and tributaries, lakes, springs, and irrigation reservoirs.

As part of the Species at Risk Action Plan for Waterton Biosphere Reserve 2015-2018 the WBR embarked on a project in 2017 to support northern leopard frog conservation in the area.

Waterton Lakes National Park is working toward establishing a self-sustaining northern leopard frog population and frogs have been successfully reintroduced to Beauvais Lake Provincial Park and Magrath in recent decades. The WBR’s Northern Leopard Frog Project has raised public awareness on the importance of northern leopard frogs in our ecosystem and provided opportunities for WBR residents to help improve their status in our area.

From 2017-2019, we solicited local knowledge about past and present northern leopard frog occurrences, identified possible locations for habitat improvement or future reintroductions, completed visual and environmental DNA (eDNA) surveys (testing for certain species’ DNA in water samples) at several wetlands on private lands within the WBR, and leveraged interest into opportunities to educate on other amphibian species at risk, associated wetland habitats, and their stewardship in the WBR. 


Frogs are important for many reasons:

  • Amphibians are among the most at-risk groups of organisms on our planet; an estimated 40% of all amphibian species are threatened with extinction.
  • Frogs provide a natural form of pest control, preying readily upon insects.
  • Amphibians contribute to ecosystem integrity – the loss of one species may not appear to be a problem but reduces ecosystem structure and function.
  • Tadpoles can limit algae growth and oxygen depletion which can cause the death of other wetland species.
  • Frogs are important links between aquatic and terrestrial habitats, contributing to the cycling of nutrients.

Click on the poster to enlarge

Next steps:

We are now working on a stewardship plan for northern leopard frogs in the WBR. This plan will build on previous landowner outreach activities and site surveys, review best management practices, and compile advice from local and regional experts. Please stay tuned for more information.













  • The northern leopard frog is the largest frog found in Alberta.
  • On average, adult frogs can range from 50 to 130 millimetres (two to five inches) in length, measuring from the tip of the nose to the back end.


  • Either green or brown, with a pale white belly.
  • Can be easily identified by its large dark spots bordered with pale rings. These spots can be found dotting the back, sides and legs of the frog.
  • Has prominent, light-coloured dorsolateral folds; these are glandular ridges that separate the back from the sides of the frog, and that run along the frog’s back from the eyes to the tail.


  • During mating season, males call to attract females. The call is low-pitched and can sound like a door creaking open, followed by several clucking or grunting noises.
  • Click here to listen to northern leopard frogs calling at a marsh in Manitoba on a May afternoon. Boreal chorus frogs are also heard in the background.


  • The northern leopard frog is found in a variety of habitats and is relatively cold-adapted.
  • This frog is associated with a wide range of permanent water bodies, and can often be found along the edges of ponds, marshes, streams, rivers and lakes.
  • Leopard frogs prefer clear, clean water in open or lightly wooded areas. They rarely occur in dense forested areas.
  • Unlike other local frogs that burrow into mud through winter, northern leopard frogs stay relatively active beneath the ice of a waterbody. To get through winter, they need waterbodies with water of sufficient depth that do not freeze through and that contain highly oxygenated water, such as creeks, rivers, springs, or large lakes/wetlands.
  • Preferably, breeding and overwinter sites do not contain predaceous fish such as trout or pike.
  • Both breeding and overwintering may take place within the same waterbody. Often, a separate breeding wetland and overwintering site within 1 km of one another are suitable for supporting northern leopard frogs.

When active

  • In Alberta, the active season for this frog runs from April to October.
  • Are most active in warm, wet weather, or at dawn or dusk if the climate is not too cool.
  • Will rest during the day in wet areas or shallow pockets in the soil, areas where they can absorb moisture and avoid predators. The frogs bask in the sun to raise their body temperature and speed food digestion.

The above identification information is adapted from information provided by Alberta Environment and Parks.


2020 Project Update

Click image to enlarge map

The Waterton Biosphere Reserve Association’s Northern Leopard Frog Project had a successful third season in 2019! Visual surveys and environmental DNA (eDNA) (testing for certain species’ DNA in water samples) were used in search of northern leopard frogs and other amphibians. The focus of the fieldwork was on private lands near Beauvais Lake Provincial Park, Waterton Lakes National Park and Magrath where northern leopard frog re-establishment efforts are in progress or have been successful, and on other areas with historical records. We are happy to report that northern leopard frogs were found at one site not previously documented! This is in addition to the five new sites documented in 2018. Five other amphibians that call the Waterton Biosphere Reserve home were also observed: tiger salamander, long-toed salamander, western toad, striped chorus frog, and Columbia spotted frog.

For more information on these amphibians click here.

Thank you to everyone who submitted information on northern leopard frog sightings in the WBR area and to those landowners who allowed us access to your properties. Your support was critical to the success of this project!

We are still interested in information on northern leopard frog sightings in the WBR and welcome you to contact us.

Northern Leopard Frog Stewardship

Discover how you can help support a healthy environment for frogs and other amphibians. 

Amphibians on My Land (ACA)
Cows and Fish – Alberta Riparian Health Management Society
Alberta Environmental Farm Plan – Species at Risk Initiative

Project Supporters: