How do you get unusual bugs on HorseIsle 2?

Check inside the pitcher plants on the marshy isles, some of them will have 'unusual bugs' inside them.

-- you can also take a boat to pitcher isle, which is near there, I've seen lots of pitcher plants.

but my problem is (and may be a glitch or something) that there is a wall of marsh, logs, and trees now confining me on the island, and not allowing me to the docks. soo i would check this out with others before you go?