White whales might be the ones swimming in the spotlight this year, but deep in the southern reaches of the Pacific Ocean, a whale of a different colour is exciting scientists.
A grey morph southern right whale photographed by the Marine Conservation Program in 2012. Image: WhalesTas/Facebook
A "grey morph" southern right whale (Eubalaena australis) was seen recently off the coast of Macquarie island, which sits halfway between New Zealand and Antarctica. While we've seen oddball cetaceans before, scientists in the region explain that this mutation is actually different than most. 

You may remember "Patches", a black-and-white bottlenose dolphin we wrote about last month. Like many other splotchy animals, Patches is leucistic (also known as "pied", "piebald" or "partially albino"). The condition causes a partial lack of the pigment melanin, and those born with it can sport a wide range of patchwork prints. "Grey morph" right whales, on the other hand, all look the same. 

Every grey right whale has both a dark ring (or "collar") and spots along the body. In addition to that uniformity, there's another quirk: these whales are actually born white. It's estimated that 3-4 percent of all right whale calves are white when they enter the world, and of those, only some will become brindled beauties when they grow up.
The 'grey morph' right whale spotted near Macquarie Island just recently. Image: Kim Kliska, WhalesTas/Facebook
"The sighting is exciting simply for its rarity, as such a small proportion of the population exhibit this colouration," Tasmanian marine biologist Dr Kris Carlyon told The Mercury. The mutation almost exclusively affects males, so it's likely that this individual travelled north for the breeding season, and is now returning to feed in the cold, nutrient-rich waters of the Southern Ocean. 

Lore has it that right whales got their name because they were the "right whales" to hunt at the height of the whaling era. These animals have thick blubber, and their plentiful oil and baleen fetched top dollar. Groups of grey morph whales haven't been seen since that time, likely because they were easier for whalers to spot than their darker cousins.

The last population survey of southern right whales was done in 1997, a time when just 7,000 of some 60,000 remained in the wild. Thanks to their endangered species listing and increased protections of critical breeding habitat, populations have begun to bounce back in recent years. We don't know for sure, but experts suspect that number has at least doubled. 

"From a conservation perspective [the recent grey morph] is simply another southern right whale," adds Carlyon. "All sightings of southern rights, whether grey or black, add to our understanding of this endangered species."

Top header image: Benjamin Dumas, Flickr