Eye of the Monster / Sea Siege by Andre Norton

Paperback. Condition: Good. 1962. Ace.

Sea Siege
After surviving the nuclear holocaust of World War III, the inhabitants of a West Indies island realize they are imperiled both by fall-out and by the sea

Eye of the Monster
Rees Naper had survived the onslaught of the alien Ishkurian "crocs," but had to cover miles of jungle and pass through croc armies to reach safety. To do that, he would have to think like a croc, move like a croc... and see through the eye of the monster.