A rare, almost all-white grey whale has been spotted again for the first time in seven years, and there is a very good chance it will be swimming past Vancouver Island soon.

The whale, named Galón de Leche — "Gallon of Milk" — has been seen only once before in 2009. The whale has just shown up again off Mexico, but this time with a calf.

"Well, it's pretty exciting," John Ford, head of the Department of Fisheries and Oceans' Cetacean Research Program in Nanaimo told All Points West host Robyn Burns. "These kind of leucistic or albinistic whales are really rare."

Ford said this isn't the first time a grey whale with albinism has been recorded, mentioning one had been seen in the 1970s. He also says there have been a few examples of all-white orcas in B.C. waters, like one that was known as "Alice" in the 1940s and '50s.

"That was a pure white killer whale that people would report. The curator of the Royal B.C. Museum at the time wrote a paper on Alice and her wanderings for a couple of decades."

Migrating past in May

Ford says Gallon of Milk's colour is probably caused by recessive genes that were not passed down to her calf, which is a normally-pigmented, dark grey whale.

And while albinism and related conditions can put humans at greater risk of getting sunburns, he doesn't think Gallon of Milk will be in any danger.

"Because they're underwater virtually all the time, the skin doesn't get burnt," he said. "There's a concern, probably, for increased predation when the whales are young. … A little, white grey whale calf would certainly stand out, but clearly Gallon of Milk survived that vulnerable period."

Gallon of Milk tail

Gallon of Milk's tail as she dives under the waters of Mexico. (National Commission of Natural Protected Areas/Government of Mexico)

Ford says grey whale migration is just starting, and mother whales with new calves usually come by Vancouver Island in mid-May on their way to Alaska to feed.

"Finding her might be a little tricky, but she would be in a smaller group of mums with calves," he said. "I'm sure the whale watchers of Ucluelet and Tofino will be keeping a sharp eye out for her."

To hear the full story, click the audio labelled: Pale whale could be migrating through an ocean near you