text: poisonous toads? i live in so. florida and i have dogs so i worry about bufo marinus.  i don't know how to tell them from other toads.  how do i identify them?  i have lots of toads in my yard. cane toads are the largest species of toad in the world, and adults can reach 4 or 5 inches in body length (one record holding specimen is close to a foot in length).  they are grey, brown, reddish or greenish in colour, with mottled patches of brown, black or dark reddish brown.  behind their eyes they have very large parotid glands, which are the glands that produce bufotoxin.  cane toads produce very virulent toxins, and can actually squirt it as much as a meter away.  this toxin can kill quite a large number of predators, and is potent enough to injure or even kill humans.  cane toads are not the only species of toad that produces bufotoxins however.  there are a large number of toad species that secrete all manner of toxic substances.  some of them might not be potent enough to affect your dog, but some of them can be.  in general, you shouldn't let your dog come into contact with any kind of toad if you can help it.