I fish for Pickerel often and they can fill an interesting space in a pond. Pickerel while shaped like Pike and Musky do not grow anywhere near as large. Fish over four pounds are uncommon. Pickerel prefer fish shaped long and narrow like they are. Adult Prickle could eat a large sunfish would probably prefer small bass because they would be easier to get down. They would be very useful in a pond that is stunted with a bunch of small bass do to lack of harvest. I have no idea how many you would need to stock. They could also be useful in controlling large shiners, and shad in ponds with out LMB big enough to do the job.