The July discovery of coastal tailed frogs during construction of Olympic downhill runs on Whistler Mountain caught many by surprise, including Whistler-Blackcomb — nobody had any idea the tiny amphibians were here until they were discovered by an environmental assessment team working ahead of construction crews.
The discovery delayed work in several areas as the mountain planners now have to put together management plans that will require relocating the frogs to new natural or man-made habitat areas.
Last week Bob Brett launched the second phase of a local amphibian study, which is part of his Whistler Biodiversity Project. The goal of the project is to catalogue all of the species plants, fish, amphibians, birds and mammals in the valley, as well as the habitats where they can be found, to use as a reference for future conservation efforts, development and for identifying and mitigating the spread of non-native species.
Previous studies have focused on flat water in the valley, but the latest eight-day field study — led by herpetologist Elke Wind — also included creeks on local mountains.
“I’d say tailed frogs were in about half the creeks we sampled,” said Brett. “They’re definitely in a lot of creeks, and there are hundreds of creeks in the Whistler area that could potentially have them when we include all the tiny tributaries that offer the right kind of habitat.”
They visited 45 mountainside creeks altogether, including 30 on Whistler and Blackcomb mountains with assistance from the Whistler-Blackcomb Employee Environmental Fund, and 15 on Rainbow and Sproatt mountains on the other side of the valley with funding from AWARE, the RMOW and the Community Foundation of Whistler.
According to Brett, it was easy to miss the frogs in the past because they are hard to spot — a full-grown frog is just 2.5 to 3 cm in length, and tadpoles typically cling to the underside of rocks. To find them researchers have to lift rocks, and catch the displaced tadpoles in nets placed downstream.
“It’s not difficult actually when you know what you’re looking for, but if you aren’t specifically looking for these frogs they’re pretty easy to miss,” said Brett.
The frogs like fast moving, clear water and can usually be found from the treeline down in tributary creeks as small as 50 cm wide. The water can’t be too cold or too warm, as they prefer temperatures between five and 18 degrees Celsius. They also prefer the shade, and were found in several creeks that have had bridging or logs placed across them on ski runs.
The coastal tailed frogs are blue listed in B.C. and have been identified as a species of special concern by the Committee on the Status of Endangered Wildlife in Canada. As a result, the frogs are protected from being killed, collected or harmed under the provincial wildlife act, and special measures have to be taken working in tailed frog habitat.
Finding the frogs throughout Whistler will have an impact on how activities like logging, construction and development will take place.
“The main reason to look for tailed frogs is to relate their presence to the types of creeks they are found in and use that as an indicator for the future,” said Brett. “We still have to analyze the results but we’re hoping we’ll be able to say ‘do these things, keep the water clear and we’ll have tailed frogs’. For example, with the new community forest, if we start cutting trees we’ll want to take steps to protect those kinds of habitats. If the frogs are still there afterwards then we’ll know we’ve done a good job.
“And because it’s a blue-listed species, we now have an obligation to have a strategy to make sure there’s a process to work around these frogs.”
The amphibian study ran for about two weeks this summer. Red legged frogs, another rare species, has yet to be discovered locally but Brett feels it’s only a matter of time. As well, the western toad is also a species of interest, requiring some action on the part of the municipality.
This year Brett hopes to create a local chapter of the B.C. Frogwatch Program to report on sightings and watch for the expected invasion of bullfrogs. Bullfrogs have been moving throughout the Fraser Valley and have been found as far north as Squamish, and create problems everywhere they go by destroying local species and habitats.
“The bad news is that they grow to the size of dinner plates and eat everything, including other amphibians, fish, ducks, that sort of thing,” said Brett.
Locals involved in the amphibian study will present their findings this November at a talk hosted by the Whistler Naturalists. Presenters include Brett, Wind, Connor McGillion and Leslie Anthony.