Fly fishing - Page 13

Barbed Hook Restrictions in Catch-and-Release Trout Fisheries: A Social Issue

D. J. SCHILL and R. L. SCARPELLA

Idaho Department of Fish and Game, 1414 East Locust Lane, Nampa, Idaho 83686, USA

Abstract.—We summarized results of past studies that directly compared hooking mortality of resident (nonanadromous) salmonids caught and released with barbed or barbless hooks. Barbed hooks produced lower hooking mortality in two of four comparisons with flies and in three of five comparisons with lures. Only 1 of 11 comparisons resulted in statistically significant differences in hooking mortality. In that instance, barbless baited hooks caused significantly less mortality than barbed hooks, but experimented design concerns limited the utility of this finding. Mean hooking mortality rates from past lure studies were slightly higher for barbed hooks than barbless ones, but the opposite was true for flies. For flies and lures combined, mean hooking mortality was 4.5% for barbed hooks and 4.2% for barbless hooks. Combination of test statistics from individual studies by gear type via meta-analysis yielded nonsignificant results for barbed versus barbless flies, lures, or flies and lures combined. We conclude that the use of barbed or barbless flies or lures plays no role in subsequent mortality of trout caught and released by anglers. Because natural mortality rates for wild trout in streams commonly range from 30% to 65% annually, a 0.3% mean difference in hooking mortality for the two hook types is irrelevant at the population level, even when fish are subjected to repeated capture. Based on existing mortality studies, there is no biological basis for barbed hook restrictions in artificial fly and lure fisheries for resident trout. Restricting barbed hooks appears to be a social issue. Managers proposing new special regulations to the angling public should consider the social costs of implementing barbed hook restrictions that produce no demonstrable biological gain.


This research confirms the earlier work (1987) of Robert Behnke, the leading trout researcher in the USA. 

Behnke, 1987. Catch and Release Fishing, A decade of experience. Proceedings from USA National Sport Fishing Symposium.
Summary of Catch and Release based research over previous 10 years for National Sports Fishing Symposium, USA. “consistent agreement among hooking mortality studies that demonstrate no significant difference in mortality of fish caught and released on single, treble, barbed or barbless hooks.”

Professor Behnke wrote an editorial on pg. 56 in the Fall 2007 issue of TU's Trout magazine titled "Trading Stubbornness for Science". Trout Unlimited is dedicated to the preservation of cold water fisheries. To their credit, they did due diligence and refused to perpetuate the lie that barbless hooks improves the fishery.

To quote Dr. Behnke, ".....statistical analysis of many hooking studies performed over many years agreed that the type of hook was insignificant in determining mortality. Several state agencies, without an understanding of this scientific data instituted barbless-only restrictions on special regulations waters. When angling violations records were examined in Idaho and Oregon, the barbless violations were the most common. Almost all of these violations were accidental; a fly is broken off and in a moment of excitement, a new fly, not fitting the narrow legal description of barbless, is tied on and the angler commits a violation."

"In view of the fact that there is no scientific or biological justification for the barbless hook regulations, a change in the law in Idaho and Oregon was proposed. Public meeting were held. The hard core, no-kill, barbless-only fanatics generated lots of heat, but no light, in a passionate defense of an irrational opinion."

"I have characterized such irrational behavior by some anglers as a trivial pursuit and the arrogance of ignorance......"

If any requirement of C&R fishing is to adversely impact fish population, it must, either in whole or in part along with other practices, be sufficient to adversely impact the fish populations above the natural mortality level. It is only then that the trout population will be below the river's carrying capacity.

The are reasons to be gentle on trout that will be released, but let us not forget that what is important is that quality trout are present at the carrying capacity of the river. Sometimes this means harvesting fish, other times releasing fish, and that barbless vs barbed hooks has no effect on fish populations.

There are reasons to go barbless because they cause less scarring of fish, less scarring of fishermen and so on.