People have this conceived notion that catch and release fishing helps keep fish stocks from depleting and ecosystems healthy. However, research has shown that fish released back into the water don’t always have a high survival rate after being subject to the stressful situation. Rebecca Eberts is a biologist and research technician who studies the ill effects of catch and release during fishing tournaments. A recent article on CBC news covers some of the university’s findings.
 
Eberts is part of a research team studying the negative effects on the fish living in Last Mountain Lake in Saskatchewan, Canada. This lake has hosted the Last Mountain Fall Walleye Classic catch and release fishing tournament for almost 30 years, making it a great research location. What they’ve discovered thus far is that the fish can become stressed to the point where their health and ability to survive is compromised.
 
Barotrauma Stress
 
One of the most common conditions fish experience is barotrauma. This occurs when a fish’s swim bladder fills up with air because of the pressure change they experience when brought up from deep waters. They can be brought up from 9-19 metre depths, and if their swim bladder fills with air then they go belly-up along the surface. Fish use their swim bladder to adjust their buoyancy while in the water, but once the bladder is filled with air, they become easy prey for the next hungry predator. Eberts tells the CBC that when encountering a fish with barotrauma “you might think it's a big, heavy fish, but if you actually touch your finger to its belly, it'll be rock hard. It'll feel like air, like a balloon".
 
Barotrauma is not only an issue that the fish in Last Mountain Lake face, but has become a problem for fish species around the world. Now catch and release fishing has drawn more attention, specifically to the health of the fish being caught. Ebert says that fish with barotrauma have a slim chance of survival if they’re released back into the water untreated.
 
Developing Treatments for Fish under Stress
 
Eberts and fellow researcher Richard Manzon have been experimenting with three different methods to treat fish with barotrauma:
 
Venting/Fizzing: When caught, the fish’s swim bladder would be punctured with a hypodermic needle to alleviate the pressure. However, Manzon errs on the side of caution with this method because if administered inappropriately, the fish will experience more harm than good.

Descending Device: This fairly new technique puts the fish on a weighted hook after being caught so that it can be brought back down to the depth where it was swimming previously. The hope is that the barotrauma can be reversed with the descent.

Weight Clip: A weight would be clipped to the fish’s fin to keep it from staying belly up. By turning the fish upright it gives it the chance to reorient and hopefully recover. This technique is still being studied by Manzon so its effectiveness remains unclear.  
 
Eberts and her team have put some of the techniques to the test, and will continue to monitor their effectiveness. During the tournament weekend they aimed to tag and release 18 fish affected with barotrauma. They administered some of the techniques on the fish in order to monitor their state over 10 days. 24 fish were also put in a holding tank near the lake to test the fin weight technique.
 
Their findings are not yet conclusive but they predict that fish with barotrauma won’t last very long without treatment. However, their final results won’t be published until later this winter.
 
What does the Tournament Say about These Findings?
 
The Last Mountain Lake’s tournament of 2016 hosted 135 teams of two who competed to take home the grand prize of $18,000. In order to win the grand prize, the teams competed to see who could catch the most Walleye in the lake. Up to 675 fish were caught during the tournament, and one can only imagine how many fish were put under stress during this time.
 
After hearing about the findings, the tournament organizers were on board with taking action to reduce stress on the fish during tournaments; they’re even willing to sponsor and invest in treatments. The hope is that anglers competing in the tournament can learn some of the techniques being developed and being to administer them on the fish themselves.
 
Besides barotrauma, fish face a number of other stresses after being caught and released back into the water. Fish endure temperature stress from being brought up from the cold depths to the warm surface, exhaustion from fighting the angler’s hook, and also damage to their internal organs from swallowing the fishing hook. If we want to maintain, or even improve the health of the Earth’s fish stocks, we must become aware of the issues our fish stocks face on a local, national or even international level.
 
Without much thought, catch and release may seem like a good way to experience the joy of fishing without depleting fish stocks. However, as revealed by Eberts and her research team, fish populations are still under threat from the stress they endure from being caught and released. What it comes down to is what our society values more, the health of our fish and their ecosystems or fishing tournaments which negatively affect the Earth’s fish stocks.