Oil spills can cause substantial environmental damage. what are examples of the types of wildlife that are affected and the impacts that oil spills have on habitats? why are oil spills difficult to manage and why do they have long-term impacts?

Spilled oil can harm the habitat because of its chemical constituents being poisonous. This can affect organisms both from internal and external exposure to oil. Oil can also end the lives of some small species of fish or invertebrates, reducing birds' and mammals' ability to maintain their body temperatures. 

Since most oils float, most sea creatures are heavily affected by oil. Examples include animals like sea otters and seabirds. 

Most states have issued some set of regulations to follow. Environmental Protection Agency's Rescuing Wildlife page gives overview information about the issue. Additionally, Tri-State Bird Rescue and Research website and the Oiled Wildlife Care Network website explain the situation elaborately.