Chilean waters could be home to new species of orcas
New unexpected evidence and recent study suggest rare killer whales spotted in Chilean Antarctic could be an entirely different species.
Wednesday, August 14, 2013
Passengers observe orca whales while travelling through Chilean Antarctica. Photo via Wikimedia Commons.
Travelers and tourists journeying through Chilean Antarctica caught more than beautiful landscapes and fauna in their vacation photos. The images also unexpectedly captured a rare group of killer whales that have reinvigorated a study into a possible new species.
“These orcas, you notice they’re different, they have an incredibly distinctive look,” Phillip Morin, a geneticist from National Oceanic and Atmospheric Administration’s (NOAA) Southeast Fisheries Science Center (SEFSC), told The Santiago Times.
The killer whales were caught on film by fishermen and tourists travelling in Chile’s Drake Passage in 2005.
“Compared to other orcas they have a very small white eye patch and a bulbous forehead. And that sets them apart from all other killer whales we know about,” Morin said.
Although researchers thus far have not been able to get samples from any of the living rare orcas, they believe they may have caught a break with a specimen that washed up in New Zealand in 1955.
The unique killer whale specimen, thought to be an elusive “Type-D” orca, has been preserved and kept at the Museum of New Zealand Te Papa Tongarewa by researchers who hoped to one day have more evidence and specimens to show this strange orca was not just a result of genetic deformity. After fifty years, scientists were losing hope, but then the photos from Chile reignited the study.
“It was completely unexpected,” Morin said. “I was caught off-guard.”
Morin is part of the team that has been analyzing the Mitochondrial DNA of the New Zealand whale. Mitochondrial DNA can stay preserved for much longer than regular DNA and is passed down through the mother, making it possible to identify family lineage.
Samples from the New Zealand whale show the “Type-D” orca diverged from other orca somewhere between 424,000 to 390,000 years ago. So far researchers have been unable to confirm that the rare killer whales sighted in Chile are this elusive “Type-D” and need to analyze the Mitochondrial DNA from the living whales to determine exactly where they fit into the known family of orca.
“We haven't done genetics on living Type-D killer whales,” Morin told The Santiago Times. “So we can't be sure they are all one type, but their appearance and the fact that all have been seen at similar latitudes in the circumpolar subantarctic waters indicates that they are likely to be the same species or subspecies.”