From Chris Royston, weekly collaborator here at Into Spanish Translation Blog:

Some animal related idioms. "Ser un lince" means "To be a lynx". The colloquial translation is "To be as sharp as a tack". A related phrase is "Ojos de lince", which translates to "Lynx eyes". In English we would say "Eagle-eye" or "Hawk-eye", as in Hawk-eye Pierce of MASH. In English, when one is in a potentially lethal situation we say that the person is "In the jaws of death". In Spanish one would be in "The mouth of the wolf" as in "La boca del lobo".

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