The short answer to why not vent muskies is, in summer, they would sink below the thermocline and suffocate, that is if the act of trying to vent them didn't kill them first. Understand, I have not reviewed current research that pertains to "fizzing" venting but when the Ohio Division of Wildlife researched its effectiveness on hundreds of tournament caught walleye they learned it was not a catch and release method they could recommend. Note: this was in spring on Lake Erie, cold water and no thermocline. The act of sticking the fish with those venting needles takes experience and a knowledge of fish anatomy and one can easily cause mortal injuries to internal organs. I can tell you from experience many muskie anglers would not even remove scale samples for fear of hurting the fish.

Sure muskies can struggle to swim down any time of year when they are hooked in the gills or handled too long especially out of the water. However, when water temperatures have reached the 80's , morning surface temperature, the muskie angler interested in successful catch and release should delay muskie fishing until the water cools back down. An example I can give you is in the Division of Wildlife's fish hatcheries, the hatchery managers try to avoid even handling channel catfish at these temperatures due to the fact the fish experience increased mortality from handling at these high water temperatures , low oxygen levels. Muskies caught at these temperatures are most likely experiencing mild stress before even being hooked. Alum Creek Lake fish are especially vulnerable to stress in July and August because of its deep thermocline. The heat was so bad last summer the 80+ degree water made it all the way down to the thermocline at 18-feet and even the muskie fishermen who did keep fishing were no longer able to get one to strike. Two years ago we were blessed with a cool summer and this was not the case.

So, practice good catch and release tactics and back off fishing when water conditions warrant it and I recommend leaving the venting to the salt water guys.