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Idaho Fish and Game

If the Fin is Intact, You Must Throw it Back

"It's a keeper!" The meaning of that expression has changed over the years among Idaho anglers, especially those who fish for salmon and steelhead. In the old days "a keeper" may have described a lunker, a fish worth taking home because of its size. These days, an angler referring to "a keeper" is probably looking at a fish that is missing a fin. The Idaho Department of Fish and Game marks hatchery salmon and steelhead by removing the adipose fin, a small fleshy fin found on the back just forward of the tail. If a steelhead is missing its adipose fin, you know it isn't wild, and you can keep it. Before Fish and Game started fin clipping hatchery fish, anglers were required to measure a steelhead's dorsal fin. If it was greater than 2 _ inches high, the fish was considered wild, and had to be released. That is why many experienced Idaho anglers know that a steelhead with a worn-down dorsal fin is probably a hatchery fish. While that is usually true, you can no longer use the dorsal fin, or lack thereof, when deciding whether to keep a steelhead. In fact, for the past several years the adipose fin has been left intact on some hatchery fish. Why, you ask? This program was developed through coordination with other fish management agencies and is designed to help answer the question of how effective returning adults are in reproducing naturally. This program allows more hatchery steelhead to reproduce on their own in certain river drainages, especially the Little Salmon River and the South Fork of the Clearwater River where most of these fish have been stocked. The hope is this program will help build naturally spawning fish populations where natural reproduction has been greatly limited. "Our ultimate goal is to get steelhead off the endangered species list, while continuing to provide fishing opportunity for our anglers," fisheries biologist Bill Horton said. In 2003, eight percent of the hatchery steelhead smolts released into the Little Salmon River still had their adipose fins intact. That same spring, 31 percent of hatchery steelhead smolts released into the South Fork of the Clearwater still had an adipose fin. Those two rivers were chosen for the program because few wild steelhead spawn there. That is why anglers on those rivers are more likely to catch the so called "stubbies," a name commonly used to describe steelhead that still have adipose fins, but also have worn down dorsal fins. Anglers on the Little Salmon and South Fork might wonder why they catch a higher percentage of "stubbies" toward the end of the season. The answer can be found through simple mathematics. Say 100 fish have returned to the South Fork in the fall of 2004-31 should be "stubbies", leaving 69 available to anglers to catch and keep. By March of 2005, chances are that anglers have caught and kept half of those remaining 69 fin-clipped hatchery fish. That leaves 34 fin-clipped hatchery fish and 31 hatchery fish with adipose fins still intact available to be caught. The ratio of "stubbies" to "keepers" is now pushing 50:50, and some anglers may be having a hard time believing that Fish and Game is not placing more "stubbies" in the river in the first place. If an angler's whose primary goal is fish in the freezer, having to release half of the hatchery fish caught may be more frustrating as the season wears on, but looking at the long-term goals of the department may help ease your pain. Many steelhead anglers are generally supportive of this program because they have caught and kept more than 35,000 steelhead each year since 1999, according to Fish and Game's annual steelhead survey. It is easier to throw back a few fish if you already have some steelhead in the cooler or the freezer at home. Fish and Game managers hope more anglers will consider the future health of steelhead runs, and will understand that releasing a few more fish today could lead to more and better opportunities for future generations of Idaho anglers.