Because of how this is an island where species are able to thrive, there are many opportunities for all sorts of species to live here. Some may be there to help out ecologically, and others may be users of the island. Nonetheless, this island was made for the purpose of helping out the environment, and if there were invasive species, it's definitely doing it's job.
-Many insects that take up sanction here on this island. They either use the island as a feeding ground, or different types of insects as a source of food.
-Beavers, they have plenty of logs to chomp down on, which allows them to use it for whatever they need it for.
-Potentially, there could be bees that pay a daily visit here. They're able to collect pollen from plants, allowing them to bring it back to their hive and feed the colony.
-Birds are a huge one. It can vary from all sorts of birds, such as Seagulls, Bushtits, Robins, and even Crows.