We know, we know, you’ve heard it before. Limit air exposure, use barbless hooks, reduce fighting time and so on. Odds are, you’ve heard the same guidelines for releasing fish, and hopefully practice them as well.
However, did you know that water moving backwards over a fish’s gills can actually cause harm to a fish? In other words, that reviving a fish by rocking it back in forth in the water may actually be causing damage?
According to BTT scientist, Dr. Andy Danylchuk, in a recent article in This is Fly magazine, fish breathe by passing oxygen rich water over the gills in one direction only; through the mouth, over the gills, and out the operculum (gill flaps). Therefore, by moving a fish backward in the water, water is passed over the gills in the opposite direction and doesn’t actually help the fish to breathe!
Instead, Dr. Danylchuk suggests that fish being revived should be held facing upstream when being released in moving water, or moved in a figure eight pattern (in a continuously forward direction) if being released in still water to best promote respiration. Remember, fish only swim in one direction for a reason.
For more great tips on how to release fish as safely as possible, make sure to check out Dr. Danylchuk’s article, here. We certainly learned a few things and think you will too.