A gelatinous, mucus-like creature lurks in rivers and lakes—and it's called a bryozoan. Recently, they were spotted—for the first known time—in Stanley Park in Vancouver, British Columbia, when low water levels made them more visible.

Celina Starnes from the Stanley Park Ecology Society recently examined the specimen found in the area's "Lost Lagoon," a small body of water in the southern part of the park. In video created by the Vancouver Courier, Starnes shows the brownish green mass jiggling as it's pulled from the water.

In a phone call with National Geographic, Starnes explains that the creatures have a gelatinous, firm quality, "almost like Jell-o," she said.

Bryozoan clumps like these are actually hundreds of creatures living together in a colony.