Oh I guess so
Many don't realize this but our local SOG anglers in Nanaimo on Vancouver Island participated with DFO in study on this argument of catch and release in 90's. Yes that right it has already been done,. As far as I know this study is the most closest to what we have on our area. On PG.7 of this document it reads the following:
British Columbia: Relatively few studies of hooking mortality have been conducted for coho and chinook captured in marine recreational salmon fisheries in British Columbia. Gjernes (1990) observed post-hooking mortality for 152 chinook captured by researchers trolling using flashers and hootchies ondownriggers in Georgia Strait. Lures were rigged with two size 4/0 single barbed hooks in tandem, 5 cmapart. The fish caught ranged from 35-80 cm and were held for 24-72 hrs in net pens. Mortality for all fishcombined was 9.9%; for fish 35-44 cm, mortality was 12.5%; for fish 45-62 cm, mortality was 8.2%, and for fish >62 cm, mortality was 13.6%. For all size classes, there was no detectable difference in mortality rates between fish hooked on one or both hooks. Hook location was determined to be the most important factor associated with hooking mortality; virtually all of the fish that died had sustained injuries to majorblood vessels associated with the gills and heart.
https://www.psf.ca/sites/default/files/99_127e.pdf
So you tell me with barbless hooks, and proper fishery how would mortality by 20 percent or higher? I did talk to one of them that set this up, and those weren't handled that great using barbed gear that is prohibited. Also if you look closely a lot of the numbers you keep preaching are coming from barbed fisheries or non-marine studies.
Anyways I am going to let this thread go. It was supposed to talk about catch release techniques not fish mortality arguments.