Vancouver Island man's film sheds new light on life of western toad tadpoles
A Vancouver Island man's film about western toad tadpoles that's been four years in the making captures footage he says is the first of its kind.
Comox Valley-based Maxwel Hohn worked with writer and editor Russell Clark to release an eight-minute short documentary called Tadpoles: The Big Little Migration.
"I came across these tadpoles, and I just formed an instant connection," Hohn told Kathryn Marlow in an interview on All Points West.
The western toad is found all along the inland coastal regions of Canada and the United States, from the northern part of Baja California to Alaska. The documentary contains previously unseen footage that shines a light on the near-threatened species.
Hohn began filming tadpoles four years ago, when he discovered an estimated three million of them living in a lake on north Vancouver Island. Since then, he's been capturing footage, choosing a wetsuit and snorkel over traditional diving gear to minimize his disruption of the delicate population.
"I spent hours, countless days in the water to find out what these tadpoles were up to," said Hohn.
The film follows the tadpoles as they dodge predators and search for tiny plants and algae to eat. During the day they gravitate toward the lake's oxygen-rich shallow waters, which speeds up their metamorphosis. At night, they retreat back to the lake's depths.
"They form this incredible highway, it's like a thick black mass of tadpoles that pool into the shallow regions of the lake," said Hohn.
Metamorphosis from tadpole to toad takes six to eight weeks. Legs gradually emerge, and when they form into toadlets roughly the size of a dime, they leave the lake and cross into forested areas. Conservation efforts in Whistler and Chilliwack have focused on building tunnels to protect the sensitive species during this stage of their migration. After habitat loss, death by car is one of the biggest threats to the species.
Richard Wassersug has spent most of his life studying toad tadpoles. He backs Hohn's claim that the footage brings to light new information on the species.
The tadpoles' skin is toxic to predators, but the film shows diving beetles feeding on the eye of a tadpole. That was a light-bulb moment for Wassersug, realizing that the skin over the tadpole's eye was probably not toxic.
"There are new observations that are at least suggested by what's in there that are worth following up with scientific questions," said Wassersug.
"That's a good example of how, if we actually take the time to look, we can see all sorts of new things in nature."
Hohn says he's had interest from major international production companies, which he's hoping will pick up his film.
"Hopefully the story will expand and in a few years' time," said Hohn.
