Reference Images

Gameplay Images

Okey, quick explanation:
The coloured dots represents the player's choices of direction. The black line shows where the bonusfish swims if you come from the right direction. The idea here is that we could have two kinds of bonus fish: Fish1 (orange fish hooked at the end of the line in the pic), would give a smaller bonus because it doesn't move, or at least very slowly. Whereas fish2, (green fish on pic) would escape you once before getting caught. What happens here is this:

If you come attacking the fish form below, the fish will swim up and into the longline, getting caught, and you can forget about trying to get it there. If you come swimming from above, the fish will swim down, under tha longline, and place itself close to the boat. If you jump up over the boat, you'll miss the little fish, but you'll catch the bigger one. The optimal route however, is to come swimming form above, keep dropping down, catch the small hooked fish, and swim up to catch the big fish.

The line under the pick was another picture I started but didn't get time to finish…

Real-life References

Bluefin Tuna Images

Longline Fishing Boats

Purse Seine Fishing Boats

Overfishing Net Picture

Bottom Trawler Fishing Boats

Ghost Net