When I was ship wrecked I worked out just about every day. I did the following routine.
1. single leg squats using a coconut tree for balance. (legs)
2. body weight two leg squats (legs)
3. body weight lunges. Then jumps for height (legs and power)
4. chins up using a branch of a tree. (lats and bicep)
5. body weight rows facing the sky using a low branch about 4' high. (back)
6. various types push ups (regular, narrow, legs raised) (chest & tricep)
7. dips on two fairly level branches (chest and triceps)
8 head stand push ups for delts leaning against a coconut tree. (delts)
9. lateral raises using a coconut in each hand. (delts)
10 heel raise using a branch on the ground. (calves)
11. stuff like burpes and mountain climbers (condition)
12. various abs stuff.
For cardio I played tag with the monkeys. Freakin bastards never knew when the game was played out. Played for ever. Fuckin jerks.