The desert island description doesn't say what is available on the island. I'm thinking of the classic joke island that has only 1 coconut tree & nothing else. It is an island, so I am assuming that we are talking about it being surrounded by ocean. I am not familiar with making fish snares with 550 cord for ocean use. You make some good points about the axe. However, bear in mind that it is the only sharp that you have & no mention is made of a file for sharpening it.