WHISTLER QUESTION (Whistler, British Columbia) 31 August 06 It’s a frog’s life, mate - Amphibian survey part of ongoing Whistler Biodiversity Project (David Burke)
Whistlerite Bob Brett calls himself an “ecologist,” but this year his primary focus is amphibian biology. Specifically, at the moment, he’s taking part in the classic biologist’s practice of turning over rocks to see what he can find.
“The tadpoles tend to hang out on the downstream side of the rocks,” says Brett, wearing rubber boots as he stands hunched over the River of Golden Dreams. In one hand is a small net, half submerged in the stream.
Brett and Elke Wind, a Nanaimo-based contract biologist who specializes in amphibians, along with Connor McGillion, a Whistler teen who aspires toward a career in the natural sciences, are looking for tailed frogs, which are provincially blue-listed, or threatened.
The frog survey, which continues through the end of this week, is part of the second year of the Whistler Biodiversity Project (WBP), a multi-year effort to catalogue the flora and fauna to be found in Whistler. Last year’s focus was on plants; this spring’s and summer’s surveys have focused on amphibians and bats.
While the term of the project is indefinite, the immediate goal is to have a complete listing of all plant and animal species by the 2010 Olympics. Such a database, which aims to focus on “indicator” species such as the tailed frog, can help local and provincial officials manage complex ecosystems over the long term, helping them meet environmental sustainability targets set out in the Whistler 2020 sustainability plan, Brett said.
This year’s WBP sponsors are the RMOW, the Whistler Blackcomb Employee Environmental Fund, the Association of Whistler Area Residents for the Environment (AWARE) and the Community Foundation of Whistler.
The ongoing tailed frog survey aims to look at streams in the valley bottom as well as Whistler Creek, Horstman Creek, Scotia Creek, 19 Mile and 21 Mile and other mountain streams, where the frogs tend to thrive.
“One reason for the Whistler Blackcomb Employee Environmental Fund’s interest is they found some tailed frogs on the mountain,” Brett said, referring to the ones found this summer in the Whistler Creek area, where officials were working on changes to the women’s downhill run for the 2010 Olympics.
He said the group wants to see where the frogs are most often found and then manage their activities to ensure the frogs’ continued survival.
Those doing the survey are less likely to find trailed frogs in valley-bottom streams such as the River of Golden Dreams, but Brett said it’s important that they cast a broad net, so to speak. That’s because the point of such a survey is to see how widely dispersed a species is in a given area.
Wind said tailed frogs are a good “indicator” species — that is, ones that provide clear signals about the overall health of a given ecosystem — because they remain in the tadpole stage for three or four years and are quite sensitive to changes in temperature and stream turbidity. They prefer cold, clear, steep mountain streams best, she said.
She said the tadpoles and metamorphs — those in the process of changing over from tadpoles to adult frogs — are especially fond of hanging out in the spaces between the rocks, usually on the downstream side.
“When there’s a disturbance,” she said, mentioning any sort of nearby logging or other human development, “all the spaces get filled up with sand and silt and they have no place to hide from the current.”
The tailed frog has a couple of unusual features. The first is the tadpoles’ sucker-like mouths, which they use to attach themselves to rocks. Another is the fact that male tailed frogs’ tails are copulatory — fertilization of the eggs takes place through insertion of the tail into the female. Most female frogs lay their eggs before fertilization takes place.
Tailed frogs can live to be about 20 years old, “and they reach sexual maturity at a later age than most,” Wind said.
Because they remain in the tadpole stage for three or four years, “they need permanent streams; you won’t find them in intermittent creeks,” Wind said, “so if you change the flow rate very much, it really affects them.”
Bull frogs and red-legged frogs are two other species of interest in the amphibian survey; the aim was to look for them in golf-course ponds. Bull frogs are considered pests because they’re an introduced species in western North America and they tend to eat up everything in their paths, even their own kind.
On the other hand, red-legged frogs, which also are listed as threatened, would be an exciting find here because they’re normally found at lower elevations, Brett said.
One of the project’s aims is to compile a list of “indicator” species that is a manageable enough length for officials to do ongoing monitoring while still providing enough data to ensure area ecosystems’ overall health, Brett said.
“The idea of surveys like this is to get ahead of the curve so that we don’t have to do it all over again in the future, but we know where we can expect to find them,” he said.
Brett said additional work on invasive plant species is also planned this year. Data from the survey is to be catalogued and available to citizens on RMOW’s website (www.whistler.ca).
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