I grew up fishing. Some of my earliest memories are being out on Mille Lacs Lake with my mom, dad and sister. I know of the excitement when a fish gets close to the boat and you see that little flicker of white on the bottom of the fish’s tale and you know you have a walleye or when a bass hits your bait fast and hard.
Last summer, I tried trout fishing for the first time. Until that day, the only shape hook I had ever used was a J-hook, which looks exactly like it sounds and is the most common type of hook for freshwater fishing. When my guide pulled out circle hooks, I was not thrilled.
A circle hook has a point that curves back into the hook at a perpendicular angle, creating a circular shape. And the ones we were using were barbless! I thought a barbless circle hook would be a huge disadvantage, especially as I was learning a new type of casting and jigging.
My expectations were completely upended. Every fish I hooked made it into the net. Every fish was hooked in the mouth, and I’d release it back into the river within seconds. I was a happy convert to the circle hook.
Circle hooks are commonly used in saltwater fishing. Since circle hooks increase the likelihood that a fish will be hooked in the mouth, survival rates of released fish increase. When deep-hooked, the removal of the hook often damages the organs of a fish causing high mortality rates.
A study conducted by the Department of Primary Industries in North South Wales, Australia, observed that when circle hooks were used, fish were far more likely to be hooked in the mouth - silver perch up to 79%, blue fish tuna up to 94%, and white marlin up to 100%. In addition, the study found that hook-up and landing rates were improved and strike time was not as critical.
For these reasons, circle hooks are slowly making their way onto the lines of freshwater anglers. It is already common in catfishing.
As I plan to use circle hooks this fishing season in Minnesota, I reached out to Minnesota circle hook expert Tom Jones, with the Minnesota Department of Natural Resources. He is the only person to ever do extensive research on circle hooks and walleye fishing, and on Mille Lacs Lake.
“The reason for the study was simple,” Jones explained, “there is a lot of concern about high mortality rates on the fish released back into Mille Lacs Lake.” Mille Lacs has a narrow harvest limit which means many of the walleye caught on Mille Lacs Lake will be released. His study found that 5% of walleye caught and released during a season die. To some, the rate may see small but the numbers add up. According to Jones’ study, “It’s estimated that 228,000 pounds of walleyes died from hooking mortality in 2002, compared to 153,000 pounds of fish kept for the frying pan.”
Jones’ study highlights two reasons for high mortality rates, but it’s not what you may think.
The first is simply hook size. Too small and it is more likely to get swallowed. Too big and it is more likely to cause serious injury to the fish - like a hook in the eye.
The second is hook-set. A heavy hook set with a regular hook has a far greater chance to tear through the stomach or throat of the fish or damage other vital organs.
Here is where the circle hook becomes a great choice. Because of its shape and size, even when a fish swallows a circle hook, it does far less damage than a traditional hook. And even better, when fishing with a circle hook there is no hook-set. “Because it’s a gentle hook set you don’t have as much organ damage internally,” Jones said.
There will be a learning curve to fishing with the circle hook, however statistically it shouldn’t greatly impact your catch. “I hooked ninety five percent of the fish on regular hooks and eighty seven percent on circle hooks,” Jones said. “And so some of that change in hook rate because I was getting used to using circle hooks.”
Overall, Jones’ study found that circle hooks killed 12% of fish landed whereas j-hooks killed 27%. It is worth mentioning that the sample size was ultimately very small and fish hooked were not observed in the long run. Further studies need to be done.
In the end, Jones is an advocate for circle hooks. “They’re not going to make anything worse. They can only make things better,” Jones said. “You will have lower mortality rates, and even when swallowed, circles have been shown to significantly reduce internal damage to the fish.”
While talking with Jones, I found out that hooks aren’t the only contributor to high mortality rates. A lot of the responsibility is on the angler.
- Water temperatures matter - cold water catches see less mortality rates.
- Water depths matter - a fish being pulled up from 50 or 60 feet of water will have a much harder time adjusting back into the water than a fish being pulled up from 10 feet. The rapid decrease in pressure causes gas in their bladder to swell. In fish it’s called barotrauma, in humans it’s called the bends. Not only does this make it harder for a fish to swim back down, but it causes internal injuries.
- How you handle fish matter - fish need to be held softly.
- Time out of the water matter - under a minute for a picture is probably ok, but you don’t want to be taking a lot of pictures and dropping the fish.
- All hooks can be swallowed - to reduce injuries, cut the line rather than digging around.
- Wash your hands. Fish have slime that protects them from infections. To avoid stripping off a fish’s protective slime, wash your hands in lake water.
This spring I plan to join Jones on Mille Lacs Lake to catch my first walleye with a circle hook. It will be new and challenging, and I hope others follow suit. Give circle hooks a try, especially when fishing on Mille Lacs Lake. You have nothing to lose and the fish and the health of the lake have everything to gain.