Invasive Plants:
Purple loosestrife (Lythrum salicaria) is one of the many invasive species. Despite its attractive appearance, purple loosestrife kills off native vegetation such as cattails . Many species of mammals, fish, insects, and waterfowl including mallards, muskrats, and redwinged blackbirds depend on the aquatic plants that purple loosestrife pushes out.
There are other foreign plant species, such as the Domestic Apple trees (Pyrus malus), and lilacs (Syringa spp.). Luckily, they don't cause any harm towards the park. They were placed by older home sites within Acadia National park, but are not invasive.
Invasive Animals:
The Asian shore crab (Hemigrapsus sanguineus) is an invasive omnivore species that also reproduces very quickly that is putting other native species. like common periwinkles, blue mussels, and rock crabs, and could affect Maine’s mussel-harvesting industry. It can be found in rocky environments from Maine to the coasts of North Carolina.
The European Red fire ant (Myrmica rubra) which was brought with garden plants has been spreading aggressively. It's bite hurts both humans and wildlife. It threatens both other species of ants, and other species of ground dwelling wildlife.
Asian longhorned beetle (Anoplophora glabripennis) larvae burrow into many different species of trees until eventually the trees are killed. The closest infestation has required the removal of more than 21,000 trees in a 64-square-mile area in Worcester, Massachusetts this took out nearly every deciduous tree in some neighborhoods.