Barnacles grow on sea turtles primarily because the turtle's shell provides a stable surface for the barnacles to attach to.
According to the reference provided, barnacles seek out the stable surface of a sea turtle's shell to help them avoid predation and secure food.
Essentially, the sea turtle acts as a mobile home and food source for the barnacles.
- Avoiding Predation: By attaching to the hard shell of a large, mobile creature like a sea turtle, barnacles gain protection from many potential predators that might otherwise consume them if they were attached to stationary surfaces.
- Securing Food: As the sea turtle swims through the water, it brings the barnacles into contact with different currents containing plankton and other tiny organisms that barnacles feed on. The movement helps them filter feed effectively.
However, it's important to note that this is not considered a symbiotic relationship where both parties benefit. The reference explicitly states that sea turtles don't directly benefit from the barnacle's presence. In fact, a large number of barnacles can potentially cause problems for the turtle, such as increasing drag, interfering with swimming, or causing irritation.
