You might want to take a look at the "In" keyword.
That way your query would be something like this:
Select name, description, imageURL
From animals Where name In
(Select name From states Where state = 'WA' Or state = 'OR')
Order By name Asc
The inner query generates a list of animals in the 2 states and the outer query selects all the animals whose name appear in that list.
I hope that was what you were trying to do. :)
Let me know if it works.
Edit: Formatting and explanation.