Transcript:

Today on Animal Fact Files we’re talking about freshwater stingrays. We keep it fresh on this channel, don’t forget to subscribe for new videos! Most stingrays live in saltwater, but not these round bois. In fact, unlike other stingrays who are only able to tolerate freshwater, freshwater stingrays are not able to live in saltwater. It’s thought their lineage goes way back to previously marine stingrays who swam up into all the rivers of South America when ocean levels were higher and there was more water covering the land mass. As time went on, these stingrays just stuck around in the water that was left as sea levels shrank. So now we have freshwater stingrays. Technically, their are other stingrays called freshwater stingrays outside of South America, but in this episode we’re specially focusing on the ones found in South American locales. Freshwater stingrays may be found in any bodies of water that feed into the Atlantic Ocean or Caribbean sea. There are somewhere around thirty species of freshwater stingrays, and while some are confined to one or two particular rivers, others are more widespread across the continent.

It’s been observed that young freshwater stingrays tend to live in shallower waters with more places to hide from predators, while older individuals stay in deeper waters, though this can vary by the species. Of course, like their marine cousins, they all tend to stay towards the bottom of the water column and burrow into the sand. Stingrays have eyes poking out of the top of their head that give them almost 360 degree vision. Their eyes will stick out the sand while the rest of their body remains submerged. They can sit like this for hours, and breathing isn’t an issue because they have spiracles behind their eyes through which they pass water down to their gills located on their undersides. Lucky for them they have holes in their heads or else they’d be sucking up a lot of sand.

Freshwater stingrays are really rotund. They may be flat enough to hide under a layer of sand, but they almost all look like a circle with a tail. Most of them have tails that are shorter than their body length, though some species do have longer tails. Freshwater stingrays can be more than three feet (0.9 meters) long, and they’re considered a delicacy by caimans and humans alike. Humans, however, also have to deal with their sting. Like many other stingrays around the world, freshwater stingrays come equipped with spines located on the top side of their tails. At the base of these spines are venom glands which means getting struck by a stingray, even a freshwater one, can be a painful experience. Even in freshwater areas where these stingrays occur, people do the stingray shuffle.

Freshwater stingrays don’t, however, use their spines to catch food: they’re strictly defensive. They will use ampullae of Lorenzini (which we’ve discussed in a previous episode) to locate their prey. Freshwater stingrays eat crustaceans, molluscs, small fish, and aquatic insects. Their mouths, which are located on their underside, come with rows of teeth, and males usually have slightly larger teeth than females. In fact, while mating, males may sink their teeth into the back of their lady lover. Guess even stingrays can get kinky.

Female freshwater stingrays will gestate anywhere from three to nine months. Her eggs will stay inside her body during that time and then hatch inside her before she gives birth to live young; and in some species of freshwater stingrays, the females always have an odd number of pups. How long they can live in the wild is currently unknown.

For more facts on freshwater stingrays, check out the links in the description. Give a thumbs up if you learned something new today, and thank you for watching Animal Fact Files.