The lack of an immediate‐release sedative (i.e., one for which no postsedation holding or withdrawal period is required) jeopardizes fish and fisheries research and poses considerable risk to those involved in aquatic resource management and the operation of public hatcheries and commercial fish farms. Carbon dioxide may be used as an immediate‐release sedative, but it is slow‐acting and difficult to apply uniformly and effectively. Tricaine methanesulfonate (MS‐222) is easier to apply but requires a 21‐d withdrawal period. The lack of an immediate‐release sedative approved by the U.S. Food and Drug Administration (FDA) is a consequence of numerous factors, including the complexities of the approval process, the substantial human and monetary resources involved, and the specialized nature of the work. Efforts are currently underway to demonstrate the safety and effectiveness of benzocaine‐ and eugenol‐based products as immediate‐release sedatives. However, pursuing approvals within the current framework will consume an exorbitant amount of public and private resources and will take years to complete, even though both compounds are “generally recognized as safe” for certain applications by the FDA. We recommend using risk management–based approaches to increase the efficiency of the drug approval process and the availability of safe and effective drugs, including immediate‐release sedatives, for use in the fisheries and aquaculture disciplines.

Tests were conducted to determine if electric current applied by electrofishing equipment had an effect on trout egg mortality. Eggs of rainbow trout Oncorhynchus mykiss were exposed to a standardized mechanical shock and to electric current from a backpack electroshocker. To separate the effect of handling from the electroshock effect, one group of control eggs was handled the same as electroshocked eggs, but without exposure to electricity. Another control group was not handled at all. Samples of eggs were exposed to one of the three treatments on days 2, 4, 6, 8, 10, 12, 14, 16, 18, 22, or 26 postfertilization. The shocker output was measured at 0.6 A, pulse was 250 Hz, and the uniform voltage gradient in the exposure chamber was 0.9–1.0 Went. The most sensitive time in the development of the eggs to both mechanical and electrical shock was on day 8 postfertilization when incubated at 10.4°C; treatment at this time resulted in a mortality rate (determined on days 26–27 postfertilization) of 99% for mechanically shocked eggs, 57.9% for electroshocked eggs, and 29.8% among controls handled the same as the eggs that received the electroshock. The mortality of eggs that were not handled at all was 19.7%. Results from further tests with eggs of cutthroat trout O. clarki showed that the level of electric current used does have an effect on the survival of trout eggs. We also demonstrated that cutthroat trout eggs placed in artificial redds in a stream can be killed by the same level of current used in these tests. Our findings indicate that electrofishing over recently deposited trout eggs can increase mortality.

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