What does a sea turtle's niche mean?

A sea turtle's niche refers to its "job" in the ecosystem. Different types of adult sea turtles have different niches. For example, some occupy the niche of being grazers on seagrass, and others eat jellyfish. Young sea turtles have a different niche than adults. An example of this is the green sea turtle. Young green sea turtles eat small sea animals, but adults occupy the niche of seagrass grazers.

Generally, a niche is mostly determined by an animal's diet.