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6 INFORMATION AND TECHNOLOGY REpORT--2003-0002 and Carothers (1988, 1990) noted that we do not know how long fish with electro fishing injuries will survive and suggested that, at least for large rainbow trout (the sub- jects of their investigation), such spinal injuries might bias age, growth, and population studies based on mark- recapture techniques. Sharber and Carothers (1988, 1990) also cautioned that the detrimental impact of such inju- ries might be very significant for populations of fishes that are already low or endangered. In an article abstracted from the 1992 version of this report (Snyder, 1995), I concluded that in situations where electrofishing injuries are a significant problem and can- not be adequately reduced (through gear, current, or pro- cedural changes), use of the technique must be abandoned or severely limited. During the next couple of years, the message regarding potential harm to fish by electrofishing was relayed to the public by related ar- ticles in various newspapers and fishing and outdoor magazines (e.g., Holt, 1995; Ritchie, 1995; Cofer, 1996; Meyer, 1997). In direct response to my article, Schill and Beland (1995) expressed a grave concern that fishery bi- ologists may be forced by public perception ofthe prob- lem (Weber, 1997) to unduly give up or restrict use of one of the profession's most effective sampling tools. In par- ticular, they observed that scientific discussion had "fo- cused on small pieces of the puzzle" and had "largely ignored the more important question of population sig- nificance." They explained, by hypothetical example, that in most cases only very small portions of populations are sampled and even if incidences of injury and long-term mortality were very high (e.g., 50% and 25%, respectively), they would affect no more than one or two percent of the population as a whole. Furthermore, they continued, an- nual natural mortality for some species (e.g., stream salmo- nids in northern states) is so high that the long-term population effects of even greater electrofishing impacts could be further discounted. Schill and Beland (1995) also noted that biologists routinely sample lacustrine fish with gill nets and accept even 100% mortality because only a very small segment ofthe population is sacrificed. In some situations, captured fish are purposely sacrificed for sub- sequent analysis. Similar concerns over public percep- tion of the problem were expressed by Wiley (1996) after Holt (1995) told "the truth about electrofishing." How- ever, Cofer (1996), in revealing "the shocking truth," sug- gested that my article (Snyder, 1995) succeeded in stirring debate over often-overlooked side effects and that "in confronting the issue, scientists may have solved half the problem by recognizing that electrofishing-in its cur- rent form-is not always so benign." Consistent with Schill and Beland's (1995) sugges- tion of insignificant adverse effects by electro fishing on populations, biologists such as Nehring (1991) and Schneider (1992) have documented that years of electrofishing, even with AC (Schneider, 1992), had not detrimentally affected the specific populations they moni- tored or managed. However, adverse effects that may be insignificant for large, widely distributed populations, might pose a significant additional threat to the survival or recovery of much smaller, localized populations of rare, threatened, or endangered species. If electrofishing injuries occur in notable numbers of fish but do not significantly affect their population size (long-term survival, reproduction, recruitment) or health (growth, condition), perhaps the only real concerns in such situations are resource quality and public percep- tion thereof. In some fish, spinal injuries result in perma- nently bent backs (Fig. 3) or related deformities (Fig. 4) which sometimes do not become obvious until well after exposure to the electric field. In other fish, spinal injuries might only be revealed by X-rays or dissection, possibly on an angler's dinner table. The extent of concern about potential electro fishing injuries in North America has been exemplified by the formation of an informal working group on electrofishing injuries within the Western Division of the American Fish- eries Society, special sessions on the matter held during annual meetings of the Western Division in July 1991 (Bozeman, Montana) and 1992 (Fort Collins, Colorado), and the attempted establishment of an Electrofishing In- jury Network through the American Fisheries Society Fish- eries Management Section. In Europe, a workshop on the harmful effects of electro fishing was organized by the ElF AC Working Group on Electric Fishing and held on 21 and 22 May 1992 in conjunction with the 17th Session of EIFAC in Lugano, Switzerland. Until the concerns are ef- fectively resolved, the harmful effects of electro fishing are likely to be the subject of still more special sessions, workshops, and organizations. Some state and provincial agencies have reviewed their concerns about deleterious effects of electrofishing and established policies, regulations, or guidelines for use of such techniques. Emphasizing available information on 15 species of regional interest, Miskimmin and Paul (1997a,b) and Paul and Miskimmin (1997) prepared a three-part report similar to this review for consideration by the Fisheries Management Division of Alberta Environmental Protection whose 1995 policy to minimize adverse effects of electrofishing on fish was being appealed. In the third part of that report, Miskimmin and Paul (1997b ) reviewed and compared existing po licies or guidelines from Canadian and U.S. jurisdictions. They acknowledged Montana as a leader in establishing a relatively strict state-wide policy and comprehensive standards to minimize electro fishing injury to aquatic life (Montana Department ofFish, Wildlife and Parks, 1994). Alberta's 1995 policy was similar to Montana's. Ontario and Washington also have official policies or guidelines