Leopard Stingray

(Potamotrygon leopoldi)

Kendjam Lodge, Amazonas, Brazil

Potamotrygonidae

River stingrays or freshwater stingrays are Neotropical freshwater fishes of the family Potamotrygonidae – one of the cartilaginous fishes related to sharks.

Freshwater stingrays are generally non-aggressive, you pretty much have to step on them as their stingers are used strictly in self-defense. Most injuries occur while stepping on them or when a fisherman catches one and gets stung on their hands, arms or chest. This is why we weren’t allowed to fish for them. In addition to the pain of the stinger, you (or the guide!) also have a high risk of bacterial infection with potential long-term effects, so they just weren’t worth the risk of trying to catch one – plus it was mating season and no reason to mess with this.

A sting can quickly go from shock, pain, nausea, and vomiting. When the stinger gets pulled out, it breaks the skin and can cause dentin fragments to remain in the affected area and wound which can lead to secondary infections that can be fatal – or for the need for an arm or leg to be amputated.

Finally, we were in an area without professional medical help so there was NO desire by the local guides for us to target them. I found it interesting that they were in such abundance and the Kayapo’s didn’t hunt them or kill them just to avoid the risk. They were part of the balance of nature there. They do consider them a food source but rare. They are more of a by catch from entanglement with netting. Their abundance, along with the proliferation of other species means they are not even a third/fourth or fish species the tribe would focus on to eat. They don’t kill them either from fear as they know where they are and how they behave. I was surprised to see they would swim so close to them. But for the fishermen, they were frequently seen and AVOIDED as a fish to catch.

Unfortunately, the species is sought out by fish tank hobbyists for the understandable reason of their unique color. This impacts the “Pups” in the water and long-term longevity of the species, less so than the environmental and geographic ones but a harm, nonetheless. Fortunately, they are known to be extremely aggressive fish in a tank so not many people want their entire tank destroyed by one.

The white-blotched river stingray has a distinctive pattern of white dots on a black background, helping it blend into its riverbed habitat. The white blotches resemble rays of sun getting through the water.

This freshwater stingray is native to the Xingu River Basin in Brazil, a tributary of the Amazon River. The white-blotched river stingray was originally believed to occur solely in the Xingu River, but it has been subsequently spotted and documented in the Curuá and Iriri rivers. It appears to dwell most commonly in rocky river bottoms, where it finds most of its food. The fish is very limited by waterfalls and dams.

Its large pup litter size also makes this species unique. The average, white-blotched river stingray litter consists of seven or eight pups, but as many as 12 pups have been born in a single litter. Other stingrays average a species birth of only four pups per litter.

It is threatened by environmental factors. The illegal gold mining puts mercury into the water system and there is a concern that the creation of additional dams to the key rivers will affect mating/reproduction.

When flying into Kenjam, we saw quite a few manmade or damaged tributaries in this part of the Amazon. Here is a photo of an illegal mining operation from our small plane:

The good news is that when the pilot saw a damaged tributary or illegal area, he would mark the spot and take a picture. It was a way of the pilots to monitor and report the exact locations of where illegal gold mining or wood harvesting was occurring. Most of the cases we saw, which are so clearly evident when you are flying in the area were illegal gold activity.

The pilot’s reporting doesn’t go unused. It is not only reported to authorities but also to the conservation societies which support the maintenance of the fragile nature of the Amazonas and to the local police forces and environmental agencies of the Amazonas.

The white-blotched river stingray eats small invertebrates and fishes, as well as freshwater snails and crabs.

One of the rarest types of stingrays, the white-blotched river stingray is threatened by habitat loss due to increased human activity, including gold mining, fisheries, logging, agriculture expansion and dam construction, in its Xingu River Basin home. It is also sometimes captured for ornamental purposes.

If you want to read a bit more on the species, I suggest the following. I found the Science Direct one to be fascinating.  

National Aquarium - White-Blotched River Stingray

First record of plastic ingestion by a freshwater stingray - ScienceDirect

Xingu Freshwater Stingray - Potamotrygon leopoldi (sharksandrays.com)