Want to reduce mortality of trout that are released under warm water considerations?
Want to refresh your memory on the measures you take and the techniques you use?
Did you know that air time is bad? Survival rates range from 88% for fish held in the water down to 62% for fish kept in the air for 30 seconds. After one minute of airtime the survival rate drops to 28%.
Download and read the special rules for taking trout to be released in warm water that have been revised and updated with better information.
Just like humans, fish experience exercise-induced stress causing them to tire and have diminished muscle function. In order to recover from being caught, fish need to be in the water so they can breathe and pump oxygen into their system.
Holding a fish out of the water prevents recovery and can lead to death if done for too long. Even shorter durations (as little as 10-20 seconds for some species) can have serious effects on short-term and long-term fish health.
You can reduce these health effects by keeping a fish’s mouth and gills fully submerged in the water as much as possible during handling.
Fish have a layer of protective mucus (“slime”) that protects them from diseases. Contact with dry surfaces, whether they are hands, grass, boat bottoms, etc., can remove this protective slime and make fish more susceptible to diseases. Additionally, if placed on a dry surface, there is an increased likelihood that a fish could injure itself by thrashing around on lakeside rocks or the bottom of the boat. You should try to do the following:
Generally the less a fish is handled, the better, so you should prepare in advance and take extra steps to minimize handling time.
Carefully revive fish. In stillwater move the fish in a figure eight so water goes through the mouth and over the gills, not back and forth!