1,000 tadpoles go back to nature with a spot of help from aquarium
Darren Smy fell in love with reptiles and amphibians as a lad, to the point his dad wound up converting the family’s dining room to floorto-ceiling holding tanks for his collection of the critters back home in East Anglia in England.
Today, Smy continues his labour of love as he and a team from the Vancouver Aquarium Marine Science Centre release 1,000 tadpoles of the endangered Oregon spotted frog near Agassiz.
“I always loved animals and I got my first lizard when I was 10,” said Smy, the senior biologist at the aquarium. “It snowballed from there.”
The Oregon spotted frogs are indigenous to the West Coast from Northern California to the Lower Mainland and Fraser Valley.
They’re no longer found in California, Smy said, and threatened throughout the rest of their range. It’s estimated their numbers have declined by as much as 90 per cent.
Development in the Fraser Valley, wetlands drained for agriculture, pollution, pesticides and invasive bullfrogs have taken their toll on the Oregon spotted frog in their northernmost habitat.
“They are Canada’s most endangered amphibian species,” Smy said. “They face many threats, like amphibians worldwide.”
The aquarium has an insurance population, and since becoming the first to successfully breed the frogs in captivity in 2010, have released 20,000 tadpoles into the wild. They eat insects that annoy us, keep waterways clear of algae and are themselves food for other animals such as snakes, Smy said.
The frogs are kept in temperature-controlled greenhouses on the roof of the aquarium, both for the sake of space and to keep the frogs used to an outdoor climate.
Getting them to mate, however, isn’t as simple as putting mom and dad frog together. It may be less complicated getting across the busy road in your first attempt at Frogger than it is getting the Oregon spotted frogs to copulate.
“All amphibians require triggers to get them in the mood,” Smy said. “It’s taken a bit of work to figure out what they are, the triggers.”
Mood lighting doesn’t seem necessary, but getting the temperature just right is.
It has to be cold enough to get the frogs to hibernate — that’s when the eggs mature in a female and the right sort of hormones get going in males.
Then when mating season arrives, from late February to the first week of April, the temperature is set just so, and aquarium staff make it rain with hoses.
“Rain is a trigger,” Smy said. “The males will start calling, and we’ll put a couple of males in with one female — a bit of competition never hurts.”