Anesthetics are widely used for surgical, field sampling, and experimental procedures in fisheries sciences. Given the high cost and the U.S. Food and Drug Administration's (FDA) mandatory withdrawal time of the only FDA-approved fisheries anesthetic, tricaine methanesulfonate (MS-222), clove oil has emerged as an alternative anesthetic that is generally regarded as safe. However, studies regarding the effectiveness of clove oil in retarding the stress response of fish are contradictory. This study evaluated the effectiveness of MS-222 (60 mg/L), clove oil (30 mg/L) emulsified in ethanol, and clove oil (30 mg/L) mechanically emulsified in water in reducing the stress response of rainbow trout Oncorhynchus mykiss during a 15-min confinement. Clove oil emulsified in ethanol (mean, 56.3 ng cortisol/mL) was not as effective in reducing the cortisol response as MS-222 (mean, 33.4 ng/mL). Furthermore, clove oil emulsified in ethanol and clove oil mechanically emulsified in water (means, 49.0 and 56.2 ng/mL, respectively) produced a greater cortisol response in undisturbed fish. Our results suggest that clove oil is less effective than MS-222 in reducing cortisol responses in rainbow trout subjected to handling and confinement. Our results also indicate that clove oil can induce stress and possibly lead to greater release mortality of fieldhandled fish.

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We evaluated mini‐fyke nets for sampling shore‐based (SB; <1 m deep) fish communities in Florida lakes. Specifically, we wanted to determine the most effective deployment method and sample size required for adequately characterizing fish communities in these habitats. Shallow SB (0.15–0.6 m) net sets, in which nets were not completely submersed, collected significantly more individuals and a larger proportion of poeciliids. However, deep SB (0.6–1.0 m) net sets, in which nets were completely submersed, collected a larger proportion of centrarchids, cyprinids, and cyprinidontids. Net placement also significantly affected the overall catch and composition of samples. Nets placed in locations away from the lake boundary tended to collect actively schooling fishes such as Threadfin Shad Dorosoma petenense and cyprinids. Nets placed next to the lake boundary tended to collect species associated with shallow, vegetated habitats, particularly poeciliids, at greater frequencies. In some cases, the collection of these fishes was unique to a particular deployment method. Our results suggest that in long‐term monitoring of Florida's shore‐based lentic fish communities, nets should be placed in SB waters with the lead extending to the lake boundary. Although long‐term sampling objectives may vary, we determined that a sampling target of 30 net sets was sufficient for characterizing the fish community in terms of percentage composition, species richness, and species diversity. Furthermore, we recommend the continued use of additional gears to fully characterize littoral fish communities.Received December 19, 2013; accepted March 1, 2014

2012) Comparison of sinking and floating gill nets for collecting shads (Dorosoma spp.) in shallow Florida lakes, Lake and Reservoir Management, 28:1, 1-9,