Given that more new anglers seem to be trying steelheading than I can previously recall, it seems imperative to outline some basic practices to minimize the effects of C&R.
The effects of C&R are generally delineated into two types: lethal effects, which occur when the fish dies, and sublethal effects, which harm the fish to varying degrees but do not cause mortality.
In general, mortality associated with C&R and steelhead is pretty low. Most studies have found the lethal effect to be 2-7% or so, with mortality rates increasing once water temperatures exceed 70-75F. That is generally good for us because it means that sport fishing has a pretty low mortality rate, but, let’s also remember that most published studies on C&R were done by experienced anglers and scientists. Further, it is likely that all anglers were on their best behavior because they were being closely observed by scientists. So, it is possible that mortality rates are higher under normal circumstances, such as when people drag the fish onto the bottom of the boat and let it flop around for a minute. Or when someone drags the fish on bank, lifts it up by the gills to remove the hook and then throws it back into the river. I don’t see these behaviors as much as I did 15 years ago, but they are still prevalent enough that I would guess mortality rates are probably a few percentage points higher. Doesn’t matter really, the rates are still low.
Far less is known about sub-lethal effects on steelhead. We know that more exhaustive fights result in increased cortisol and lactic acid levels, and elevated levels of cortisol can have negative effects on the physiology of the fish. Otherwise, we have to look to studies on other species – like Atlantic salmon – to understand potential sub-lethal effects. For example, recent research on Atlantic salmon indicates that reproductive success of females that were C&R’d was reduced after they were exposed to air compared to fish that were not exposed to air. It is hard to say what this means to steelhead, but I think we can all agree that minimizing air exposure is probably a good thing for the fish.
The body of research, and my personal experiences as a steelheader over the past 35 years, suggests there are a few important practices that can reduce both lethal and sub-lethal effects. First, make sure and cut the leader if the fish is deeply hooked. Don’t go fussing around inside its throat to retrieve the fly. That only makes matters worse. Not all of those fish that are pumping blood will die. I have participated in a number of studies where I observed fish survive instances when I thought they would succumb to blood loss. It is not many, but some do survive deep hookings.
Second, fight and land the fish as quickly as possible, which means putting the wood to the fish, rather than letting the fish play itself to complete exhaustion. It also means using the appropriate size rod, reel, tippet and fly. This will reduce the cortisol buildup in the fish and allow it to reach stasis sooner rather than later, and it also reduces the amount of energy the fish expends. The latter could be particularly important to summer steelhead that rely on their fat stores to survive for prolonged periods in freshwater without restorative nutrition. I fully appreciate the challenge of landing steelhead on light gear, and that is completely fine for hatchery fish and in populations where most of the steelhead are small in size. But those normal 2-4 salt wild fish are too few to be hooked on 4wts with 4lb test.
Third, there are a number of safe ways to land the fish. The best way for the fish is to simply grab the leader and unpin the fly while standing a few feet from shore in knee deep water. That ensures the fish won’t slam its heads on rocks or beach itself. But that is not always possible depending on the size of the fish, length of the rod and features of the river. If fishing with a partner, have them either tail or net the fish (using a knotless net). If fishing alone, as I do the vast majority of the time, it is sometimes easiest to slide the fish into the 6”-12” of water near the shore, remove the hook and then release the fish. Any of these are generally acceptable, though the latter requires more practice and experience to ensure the fish does not go ape crazy when it does enter the shallow water.
Fourth, minimize handling the fish, period. Their slime is a protective layer, which is why handling a fish with wet hands is better than handling a fish with dry hands. Don’t squeeze the fish too hard either, as C&R studies on other species have found that hard handling near the pectoral fins can bruise the heart and squeezing too tightly on the wrist can damage vertebrae. This is why it’s best, if possible, to not lift heavy fish completely from the water. We have all tightened a death grip trying to hold onto the tail of a struggling steelhead, but avoiding that tendency on our part if important to the fish’s health.
Lastly, if you want a photo, and I take photos myself, then do your best to keep at least part of the fish’s head in contact with the water. This can be accomplished by holding the fish sideways in the water, allowing the current to wash across one sides of its gills. It can also be done by keeping the bottom 1-2” of the fish submerged. If alone, and this is the most difficult time to get photographs, make sure and keep the fish’s interest in mind. I try to slide the fish into 5-8” of water where there is clean gravel, not mud or silt. I then remove the fly so the fish can easily right itself and swim away if it desires. I pull out my camera and snap a few photos while the fish is lying on its side, then gently guide the fish back into the main part of the river. It seems about half the fish I do this with end up swimming away before I can ever get a photo, which is fine with me, and highlights why it is key to remove the hook first. Although I would suggest trying to not lift the fish entirely from the water for a photograph, if that does happen, make sure the fish is not out of the water for more than 10 seconds. That is plenty of time to get a couple shots and reduce possible sub-lethal effects from air exposure.