Stop crabs from jumping out of the pens

With the new update giving crab pots, I’d like to bring the crab I get back to one of the pens for slaughter / live storage. It would be easier to manage since they take 2 bullets to kill.

However, when I bring crabs to the pen to place them, they jump out after the first hit and scuttle away! Please make it so they cannot jump out of the animal storage pens.