Rare blue-coloured green frog found in Nova Scotia backyard pond

A family near Springhill in Nova Scotia's Cumberland County needn't look farther than their backyard for a rare sighting in nature — a blue-coloured green frog.

The Scheltgen family first saw the frog a year ago and now, they're hopping up and down after finally capturing photographic proof. 

"Last summer, my husband noticed a blue frog and we just thought that was kind of odd," Melissa Scheltgen told CBC News. "He told a few people at work and no one really believed him."

Then, just a few days ago, Sheltgen's eight-year-old son Hunter managed to find and capture it for a few photos. 

"I thought maybe we should just Google this, and see what kind of frog it is," she said. "When we did, we found out they're really rare frogs."

How rare? One in a million, internet sources informed the family.

Andrew Hebda, a zoologist with the Nova Scotia Museum of Natural History, said while statistics always depend on the number of sightings, those odds are "probably within that general range."

Hebda said this blue frog is, in fact, a common green frog — based on size and its "warty ridges." Like blue lobsters, he said blue frogs result from an imbalance of pigments. A green frog, for example, has a perfect balance of yellow and blue pigments. 

"Our [Nova Scotia] frog populations are essentially isolated from the rest of the Maritime populations," he said.

"We're on an island, for all intents and purposes." 

'One-in-a-million kind of opportunity'

He said the blue-coloured frogs are rare enough to be represented at the museum. They've had one, originally found near Pugwash, in their exhibit since last fall.

Hebda added in a small region like Nova Scotia, there can be little genetic fluctuation, which makes these anomalies hard to find.

"This frog is sort of an intermediate," he said. "The colour of blue you get depends on the species. Bullfrogs, for example, have a very pale, milky, robin's egg blue. Then you get gradation, with the greens almost into a metallic blue." 

Hebda said blue frogs can also be hard to find because they tend to stand out to predators, making survival rates lower than standard frogs.

The Scheltgen family has put their blue-coloured green frog back in their pond, but like to return to their backyard to keep an eye on it.

Melissa Scheltgen said the experience has been interesting.

"It's kind of a one-in-a-million kind of opportunity in our lifetime to see one," she said.