... Since there are only about 328 wolves in a state with a historic blood thirst for the hides of these top predators, the nonprofits are probably right that lacking protection, Wyoming wolves are toast.
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Something “is toast” means it is destroyed (or nearly so). According to a grammarphobia blog the idiom dates from the 1984 movie Ghostbusters. Examples of recent use include headlines like “Mitt Romney Is Toast Without an October Surprise” (1). The quotation in the question means that wolves will have trouble surviving in Wyoming unless protection (such as bag limits) are put in place.
The grammarphobia blog says:
All this is explained in a note in the Oxford English Dictionary, which says the use of “toast” to mean “a person or thing that is defunct, dead, finished, in serious trouble, etc.,” originated with the movie.
"[something] is toast" is a metaphor that means that the subject is doomed. In the quote provided, "Wyoming wolves are toast" indicates that the species itself is doomed to be hunted to extinction for the reasons provided.