People in the US are accidentally drowning baby tortoises by mistaking them for turtle hatchlings and "releasing" them into the water.
The Florida Fish and Wildlife Conservation Commission (FWC) says it knows of three "well-intentioned good Samaritans" who have made the error.
It's now giving advice to help people spot the difference between sea turtles and gopher tortoises.
"Gopher tortoises cannot swim well and can easily drown," it says.
"Because gopher tortoises often nest in dunes adjacent to sea turtle nesting beaches, correct identification of these terrestrial animals is important before deciding what action, if any, is necessary."
You can tell whether you are looking at a tortoise or a turtle, by just looking at their limbs from a distance - and the conservation group has released some photos to help.
"Gopher tortoises have toes, with claws on each toe. Sea turtles have flippers with only one or two claws present on each foreflipper," says the commission.
They say it is important that people do not touch or handle the animals.
"All five species of sea turtles found in Florida are federally endangered or threatened and managed under the Endangered Species Act as well as under Florida Statutes. The gopher tortoise is listed under state law," the commission explains.
"If you spot any of these species in danger on the beach, please do not disturb the animal."