Niche ideas for sapient creatures

Here are some of my ideas of niches some forms of life can have

Arboreal: living between the branches of forests and jungles. Can be perching, simian like, or burrows into the tree.

The sky: either biological jet propulsion or air bladders that are internal( similar to fish swim bladders that let's an organism without wings float.) or external bladders ( similar to balloons)

Parasite: either beneficial to both organisms or only to the parasite can exist externally or have a life cycle that requires the assistance of other animals(example: horse hair worms and insects)

Soil: organisms that can burrow or create underground hives

Islands: organisms from main land can either grow bigger or smaller on islands depending on island dwarfism and island gigantism.

Floating mountains or islands: can be done by either magnetic properties in ore or by a strong gravitational pole ( unlikely good idea for a niche since it depends on planetary gravity)

This is all I have for now. Note that any typo's are mostly autocorrect or my stupidity