Britannica Sources used in this answer

Why can many aquatic turtles move more efficiently in water than on land?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Illustrations of ten representative chelonians, including spiny softshell turtle, Galapagos giant tortoise, green turtle, alligator snapping turtle, Blanding's turtle, common map turtle, eastern box turtle, eastern painted turtle, spotted turtle, and eastern mud turtle, each labeled with its common and scientific name. A scale bar at the bottom shows size comparison. — turtle Turtles (order Testudines).

Many aquatic turtles move more efficiently in water than on land primarily due to the effects of buoyancy, which reduces the impact of their heavy, protective shells. While the shell is an essential adaptation for defense, its weight and rigid structure limit limb movement and speed on land.12

In aquatic environments, turtles utilize specialized anatomical features to enhance their mobility:

Streamlining: Many aquatic species, particularly sea turtles, have evolved streamlined shells that reduce drag.2
Propulsion: Freshwater turtles often possess elongated hind legs with enlarged, strongly webbed feet that act as paddles. In contrast, sea turtles have evolved forelimbs into bladelike flippers, which they move in a figure-eight pattern to generate lift and thrust, a process analogous to aerial flight.34
Bottom-walking: Some species, such as snapping turtles, are less adapted for swimming and function as bottom-walkers. Even for these turtles, the water environment allows for faster movement than is possible on land, as the water supports their weight and facilitates their specific locomotor patterns.3