Saucie, what exactly do you mean by property rights? This raises an interesting question of territorial domain and animal preservation. Do you think mankind has the "right" to dominate the ecosystem and push endangered animal species into extinction through habitat destruction?
Is there such a thing as a 'right to more land?' or a 'right to develop land?' I come back to your definition of a right as being a contract. If this is indeed a 'right' of corporations or individuals, then what is their responsibility that goes along with that right? What is the contract? And who decides? and when does that decision come under the global flag of "animal rights" or is it semantically more appropriate to refer to it as environmental policy?
I dont think "animal rights" should include that kind of restriction, but I also think an individual's property rights (in my mind the right to own land) should come with the responsibility of not doing excessive damage to the ecosystem.