The Largemouth Bass Micropterus salmoides is the most sought‐after species by recreational and tournament anglers in the United States. Survival of angled and tournament‐handled Largemouth Bass has been related to numerous factors, but the independent effects of water temperature, angling time, and live‐well dissolved oxygen (DO) concentration on survival have not been measured. Understanding the independent effects of these factors on fish survival is necessary to formulate realistic models to predict population effects of catch‐and‐release and tournament angling throughout the year. Survival responses to water temperature, angling time, and live‐well DO concentration are also needed to develop guidelines useful for maximizing survival of released Largemouth Bass. Five‐day survival of Largemouth Bass larger than 300 mm was evaluated after simulated catch‐and‐release and tournament handling (8 h of confinement in aerated live wells and a weigh‐in before release) over the range of water temperatures typically encountered by Largemouth Bass anglers (17–33°C) while also testing independent effects of simulated angling time (1 and 3 min), live‐well temperature change (∆T = 0, −4, and +4°C), and live‐well DO (2.0, 5.5, and 8.5 mg/L). Survival of fish subjected to catch and immediate release was 100% at all temperatures measured, and survival of tournament‐caught fish was over 80% at temperatures of 29°C or less but declined at 33°C. Survival decreased with increased simulated angling time at high temperatures and at a DO level of 2.0 mg/L in live wells. Survival rates and probabilities provided in this study should be considered best‐case estimates because all fish were handled carefully and not subjected to hook wounding. However, results suggest that high survival of angled and tournament‐handled Largemouth Bass is possible with short angling times and appropriate live‐well management.

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Serial impoundment of major rivers leads to alterations of natural flow dynamics and disrupts longitudinal connectivity. Catostomid fishes (suckers, family Catostomidae) are typically found in riverine or backwater habitats yet are able to persist in impounded river systems. To the detriment of conservation, there is limited information about distribution of catostomid fishes in impounded rivers. We examined the longitudinal distribution of catostomid fishes over 23 reservoirs of the Tennessee River reservoir cascade, encompassing approximately 1600 km. Our goal was to develop a basin‐scale perspective to guide conservation efforts. Catostomid species composition and assemblage structure changed longitudinally along the reservoir cascade. Catostomid species biodiversity was greatest in reservoirs lower in the cascade. Assemblage composition shifted from dominance by spotted sucker Minytrema melanops and buffalos Ictiobus spp. in the lower reservoirs to carpsuckers Carpiodes spp. midway through the cascade and redhorses Moxostoma spp. in the upper reservoirs. Most species did not extend the length of the cascade, and some species were rare, found in low numbers and in few reservoirs. The observed gradients in catostomid assemblages suggest the need for basin‐scale conservation measures focusing on three broad areas: (1) conservation and management of the up‐lake riverine reaches of the lower reservoirs, (2) maintenance of the access to quality habitat in tributaries to the upper reservoirs and (3) reintroductions into currently unoccupied habitat within species' historic distributions. Copyright © 2017 John Wiley & Sons, Ltd.

Advanced-sized Largemouth Bass Micropterus salmoides to be used for stocking and experimentation can be efficiently reared on prepared feed in intensive culture conditions, but formulated diets containing high levels (≥20%) of dietary carbohydrates may lead to high liver and muscle lipid and high liver glycogen levels, which may affect survival and stress responses. Largemouth Bass were raised to a size of 240-344 mm TL on formulated diets and then were fed live forage (i.e., naturalization); the effects of naturalization on liver, blood, and muscle health indices and physiological stress measures were evaluated, and indices were compared with those of wild Largemouth Bass from three different reservoirs. Hepatosomatic index (HSI) decreased by week 1 of naturalization; liver glycogen decreased by week 2; liver lightness, yellowness, and steatosis decreased by week 4; and liver moisture and lipid concentration stabilized after 4 weeks. Plasma cortisol was higher by week 1 of naturalization than by week 6 and onward, and plasma pH decreased after 1 week. Muscle color showed changes by week 1 of naturalization, muscle collagen stabilized by week 4, and muscle lipids decreased more gradually compared to the liver. The magnitude of stress response in fish subjected to a 60-s chasing stressor was unaffected by naturalization. Among populations of wild fish, many liver, blood, and muscle metrics were similar, with the exception of liver yellowness, glycogen, and HSI; muscle redness, lipids, and moisture; and the viscerosomatic index. Therefore, after rearing on a high-carbohydrate, high-lipid diet (i.e., 20% carbohydrates; 16% lipids), 4-6 weeks of naturalization can improve liver health, with most liver parameters being similar to those found in populations of wild fish.