As Whistler's annual Western toad migration wraps up, some trail closures are in effect at Lost Lake to keep the amphibians safe.
On its website, the Resort Municipality of Whistler notes the Single Track Hiking Trail on the west shore of Lost Lake and the Single Track Hiking Trail between the Passive House and Loop Trail are both closed during the migration.
"Thousands of tiny Western toads are in the final stages of migrating from the shores of Lost Lake and into the surrounding forests," the RMOW says. "During migration toads must cross trails, lawns and roads that are busy with bikes, pedestrians and vehicles. To help give the toads a better chance at survival, Lost Lake Park undergoes changes during the migration."
Despite their tiny stature, the toads play an important role in Lost Lake's ecology.
"Tadpoles feed on detritus in the lake, which helps keep our lake water clean, benefiting humans and other species. The dime-sized toadlets have also found a place in the hearts of the many volunteers who have helped them on their journey from the lake to forest," the RMOW says.
"Western toads are native to British Columbia and are sensitive to changes in their environment. Human activities—especially roads and urban development that compromise forests and wetlands—are leading to the loss of suitable habitat and the creation of migration barriers for amphibians. Western toad populations are particularly vulnerable during the tadpole and 'toadlet' life stages."
Along with intermittent trail closures, the RMOW helps support the migration through permanent features like such as signage, fencing and underpasses to protect breeding and tadpole habitat. Temporary measures like fences, signs and boardwalks are also employed.
"Underpasses have been strategically placed to allow toads to follow preferred migration routes without crossing high traffic trail networks. In addition to underpasses, the RMOW installed a new log retaining wall along Lost Lake beach to discourage toads from migrating onto park lawn areas where historic mortality numbers have been very high," the RMOW says.
"Once toads begin to migrate across the Lost Lake access road and parking lot, these areas will close to all vehicle traffic. When this happens, the free Lost Lake shuttle will continue to run, but visitors will be dropped off at the entrance to Lost Lake Park on Blackcomb Way and will need to walk the remaining 500 metres to the beach."
Lost Lake's beach, lawns and docks are still open, but the RMOW asks visitors to the area to tread lightly and walk bicycles, "as toads are no bigger than the size of a dime and can be easily crushed under foot. These areas may be subject to closure if they happen to coincide with major toadlet migratory pathways. This is difficult to predict as chosen migratory pathways can vary widely from year to year."
It's also hard to predict exactly how many toads migrate each year (but the short answer is: a lot). Females can lay up to 15,000 eggs, and this year the RMOW counted 150 breeding pairs. Annually, municipal staff observe anywhere from 35,000 to 40,000 toadlets making the journey.
Read more at whistler.ca/toads.
