great take on PvZ tower defence game which hasn't been done before at least not to my knowledge. very addicting gameplay loop, maybe some more damaging enemies maybe 1 extra one because I seemed to be stuck with a lot of octopuses and not enough damaging units to place on the isles so the sharks stomped me. but still great game would love to see it worked on more has a lot of potential!
edit.
Just played it some more and realised you can stockpile your catches adding another element to the gameplay. so my previous comment can be voided! unless you want to flesh it out more ! great job!