A 103-year-old orca whale named "Granny" has been making some serious waves this week, after she was spotted traveling for 800 miles off the coast of Canada with her pod. The centenarian, also called J2 by researchers, has not only astounded people with her age, but by disproving SeaWorld claims that orcas typically live up to 25-35 years in the wild.
So how do researchers know that this particular whale is Granny? Well, it turns out that like humans (and all other animals), each orca has distinguishable physical characteristics. The most important identifier that researchers use is a whale's dorsal fin. Each whale has a unique dorsal fin identified by its slight variations -- shape, width, height and whether or not it curves to the left or right.
Whales can also be identified by a "saddle patch," whitish-grey patch of pigmentation on their back, just behind the dorsal fin. Each one is different, like a human fingerprint.
"J2 or "Granny" is identified by both her saddle patch and her dorsal fin," said Erin Heydenreich, a field biologist with the Center for Whale Research. "J2 has a distinctive nick right in the middle of her dorsal fin which makes her hard to miss."