March 4, 2021

The Truth Behind the Collapsed Dorsal Fin

In 1993, Free Willy, a movie telling the charming story of a troubled boy named Jesse who befriends a whale named Willy, who lives at an adventure theme park in captivity. The movie prompted the release of many orca whales who were being used in training shows at SeaWorld and other parks. And one of the things that resonated most with viewers was a unique feature of Willy’s, which was his curved dorsal fin, the fin for which most killer whales sticks straight up. The most commonly accepted explanation for the collapsed dorsal fin is that when killer whales are put into captivity, they become depressed and their fins collapse as a result. But of course, there is still a debate over whether captivity can really cause a change like that in an orca whale. Animal rights activists and those who advocate trying to free killer whales and other animals in captivity fight against employees who work at theme parks and others who don’t see anything wrong with zoos or aquariums. While researchers and animal specialists still aren’t positive on the reasons why an orca’s dorsal fin may collapse, there are several theories that are on the table and evidence to support many of them.

The Purpose of the Dorsal

FinJust like there could be many reasons why the dorsal fins collapse on killer whales, there are many reasons why the animals even have the fin. Most scientists agree that the main purpose of the fin is to help animals stay stable in the water. When whales turn in the water, speed up, or slow down, the fin helps them accomplish this, and it also helps them swim more easily. Other researchers agree that the fin helps excess heat leave the body of an orca and otherwise regulate body temperature in whales. Contrary to popular belief, there is no bone in the dorsal fin; just a type of connective tissue called collagen. The dorsal fin may have many different roles in a killer whale, but most scientists agree that the collapse of the fin doesn’t have any significant negative health impact.

Why Would the Fin Collapse?

Because the dorsal fin is made up of tissue and doesn’t have a bone, it is harder for it to stand straight and stay healthy. The water provides pressure to help the tissue, which in turn makes the dorsal fin stand up straighter. Activists claim that because orca whales don’t have as much opportunity to swim in captivity, not as much pressure is put on the fin and it falls. The regulation of temperature may also play a part in the collapse of the dorsal fin. Warmer waters and warmer air temperatures could be too much for the fin to regulate, and it could collapse because of all the efforts. However, the collapse of the dorsal fin may not all be scientifically related; the biggest reason may very well be emotional. Killer whales suffer severe stress and even depression in captivity, and it makes sense that this could lead to the affliction suffered by Willy and other whales in captivity.

The Argument Against Activists

Whales in captivity are not the only ones whose fins collapse; although it is less common, whales in the wild do sometimes suffer from dorsal fin collapse. Those who don’t agree with the argument of activists claim that, as there is no bone in the fin, it is only natural that over time the fin would collapse. They also argue that the dorsal fin doesn’t serve as an inclination of health whatsoever, and can’t be impacted by diet, stress, or activity.

Although there is evidence and reason behind each side of the argument, all signs seem to point to the conclusion that the dorsal fins of whales in captivity are much more likely to collapse; and that it’s a good thing that Free Willy had the positive impact that it did on killer whales all over the country.