Task 4: Captain Kwark is shopping

Captain Kwark is sailing to a couple of Islands to do some shopping. These are the distances that he sails:
First 40 miles, then 35 miles, then 30 miles, then 31 miles, and then 34 miles.
The order is allright, but the directions are unkown.
Do you know to which islands he is sailing?

miles: 40 - 35 - 30 - 31 - 34

Question

To which Islands does Captain Kwark sail?