The results are in - circle hooks save fish. And when you fish them correctly, your hookup ratio increases as well. Invented decades ago, circle hooks burst onto the scene in recent years because of their ability to snag a fish square in the jaw and lower the chances of gut-hooking. Dr. John Graves, a fisheries scientist at the Virginia Institute of Marine Sciences, proved what a lot of fishermen using circle hooks already knew through his studies of circle hooks versus J hooks. In his initial study in 2002-2003, he placed 40 satellite tags on white marlin, 20 of which were caught on circle hooks and 20 on J hooks. Seven of the fish caught on J hooks died after release, but all of the circle-hook-caught fish lived. In a second study conducted over the past two years, Graves and his students tagged fish on three different models of circle hooks and again compared the results with fish caught on J hooks. They found that J hooks were 39 times more likely to hook fish deeply, 32 times more likely to induce trauma and 22 times more likely to cause mortality. If all U.S. anglers used circle hooks exclusively when fishing for marlin in the Atlantic, Graves says it could save up to 2,664 marlin. Now that's a lot of fish.