Survival Of Largemouth Bass Research Articles

Availability and Timing of Fathead Minnow Supplementation Influence Largemouth Bass Survival and Production in Rearing Ponds

Adjustments to rearing practices should be justified with increases in production, stocking success, or angler satisfaction. Largemouth bass (Micropterus salmoides) production was assessed between hatchery ponds where fish were restricted to an invertebrate diet or received supplemental fathead minnow (Pimephales promelas) forage during 2015. At harvest, age-0 bass yield was 4.5 times greater and average fish length was 38 mm longer, in the pond that received fathead minnow. In 2016, a second study evaluated the timing of minnow supplementation that included earlier stockings of small fathead minnow (30 mm) minnows. With earlier supplementation, bass yield was 2.3 times greater and fish averaged 14 mm longer at harvest. Bass survival was approximately 38% higher during 2015 when supplementation occurred and 25% higher during 2016 when minnow supplementation began earlier. Our findings show invertebrate forage was probably limiting bass production in hatchery ponds and supplementing with appropriately-sized fathead minnows increased age-0, largemouth bass production.

Growth and Survival of Largemouth Bass following Supplemental Feeding of Bluegills in Small Impoundments

AbstractWe investigated whether providing supplemental pellet feed to Bluegills Lepomis macrochirus in small impoundments increased their growth and reproductive rates after stocking and whether the supplemental feeding of Bluegills had positive indirect effects on Largemouth Bass Micropterus salmoides during the initial stocking year. In 2010, we stocked adult Bluegills and Largemouth Bass into nine 0.1‐ha ponds; three replicate ponds were each provided with no pelleted food (control), a low ration (1.52 kg·ha−1·d−1), or a high ration (2.68 kg·ha−1·d−1). Supplemental feeding yielded increases in the growth of newly stocked Bluegills, the gonadosomatic index of female Bluegills, and the density of larval Bluegills within 4 months of stocking. In contrast, the sizes of adult and age‐0 Largemouth Bass and the density and biomass of age‐0 Bluegills during fall were not affected by feeding within the time frame of our study. The results demonstrate that supplemental pellet feeding is useful when the management goal is to increase Bluegill size and reproductive output and that these effects develop soon after stocking. We conclude that supplemental feeding is a beneficial enhancement technique for application to Bluegills in recently stocked impoundments.Received May 13, 2012; accepted November 20, 2012

Effectiveness of Livewell Additives on Largemouth Bass Survival

Abstract Livewell conditions during competitive angling events are thought to affect fish mortality. We examined the effects of livewell additives on initial and delayed mortality of largemouth bass Micropterus salmoides. We applied three treatments (salt, ice, or salt and ice) to livewells during tournaments conducted on lakes in Illinois, United States, as well as in laboratory and pond experiments designed to examine the effects of fish size and ambient water temperature on mortality. Fish were collected after tournament weigh-in procedures were completed and monitored for delayed mortality every 24 h for 5 d. Initial mortality did not differ among livewell additives during these field experiments. Although delayed mortality was high (35%), it was not significantly different among livewells that contained salt (56%), ice (48%), ice and salt (40%), and controls (30%). Additives administered during the laboratory experiments, at cool water temperatures, resulted in significantly lower delayed mortalities than those observed during the field experiments when ambient water temperatures were warmer. Initial and delayed mortality did not differ among livewell additives during the laboratory experiments. Larger fish in field experiments had significantly greater delayed mortality than smaller fish in the pond experiments even though initial and delayed mortality did not differ among livewell additives. Our results suggest that fish size and ambient water temperature have a greater influence on delayed mortality observed during competitive angling events than the specific livewell additives studied here.

Effects of Common Carp on Reproduction, Growth, and Survival of Largemouth Bass and Bluegills

AbstractThe common carp Cyprinus carpio was introduced to North America more than a century ago, but little research has focused on interactions between this invasive species and native fishes. We used large mesocosms (600 m2) within drainable 0.4‐ha ponds to examine the effects of adult common carp on (1) reproduction of largemouth bass Micropterus salmoides and bluegills Lepomis macrochirus and (2) growth and survival of the larvae and juveniles of these centrarchid species. In separate enclosures, adult bluegills or largemouth bass were stocked with or without common carp. In enclosures with common carp, turbidity was substantially higher, but both centrarchid species spawned and the densities and sizes of larval largemouth bass and bluegills were similar to those of larvae in enclosures without common carp. As juveniles grew, largemouth bass survived at a higher rate but were smaller in enclosures containing common carp compared with largemouth bass in enclosures without common carp. In a second experiment, we stocked known numbers of older juvenile centrarchids into enclosures and found decreased growth for both largemouth bass and bluegills. However, survival of largemouth bass was again higher in enclosures with common carp. Although centrarchid spawning was successful and larval growth and survival did not decrease in the presence of common carp, centrarchid growth slowed at the juvenile stage, probably due to food resource limitation resulting from direct competition with common carp for invertebrate forage, high turbidity caused by common carp, or both of these factors.

The Effect of Water Temperature on Growth and Survival of Largemouth Bass during Feed Training

AbstractWater temperature could be an important factor during the feed training phase of largemouth bass Micropterus salmoides production, as it could affect appetite and starvation time. We evaluated three water temperatures during largemouth bass feed training. Pond‐reared largemouth bass fingerlings (weight = 2.1 ± 0.6 g [mean ± SE]) were randomly stocked into twelve 0.5‐m3 polyethylene cages to achieve a stocking density of 350 fish per cage. The cages were suspended in six 3,800‐L polyethylene tanks with a common water source housed in a greenhouse with four replicate cages per water temperature treatment (20, 24, and 28°C). Each tank contained two cages, and there were two tanks per treatment temperature. In each cage, fingerlings were initially fed freeze‐dried krill, then gradually weaned onto a commercial pellet (floating trout feed; 1.5 mm) over a 24‐d period according to an established training protocol. At harvest, the average weight and the percentage of fish successfully trained to commercial feed were significantly different among temperatures (P ≤ 0.05), increasing as water temperature increased (weights averaged 5.4, 6.8, and 7.8 g and percent trained averaged 70, 82, and 90% for fish feed‐trained at 20, 24, and 28°C, respectively). The results from this experiment indicate that water temperature has a significant effect on feed training success and the average weight of feed trained largemouth bass.

Effects of Graded Levels of Carbohydrate on Growth and Survival of Largemouth Bass, Micropterus salmoides

Abstract Excessive carbohydrates (CHO) in diets for largemouth bass (LMB), Micropterus salmoides, are suspected of accumulating glycogen in hepatocytes, which may result in liver dysfunction. This study evaluated the effect of graded levels of dietary CHO on growth, survival, and liver histology of LMB. One hundred feed‐trained advanced fingerling LMB (128.5 ± 21.5 g) were stocked into each of nine 3400‐L polyethylene tanks. Tanks were randomly assigned one of three experimental diets containing different CHO levels (13, 19, or 25% of diet). The extruded diets were approximately isonitrogenous (42% crude protein) and isocaloric (3 kcal/g energy). There were three replicate tanks per dietary treatment. Bass were fed to apparent satiation twice daily for 148 d. Survival was significantly higher (P ≤ 0.05) for fish fed the 13 and 19% CHO diets (89 and 90%, respectively) compared to those fed the 25% CHO diets (82%). Average harvest weight of fish fed the 13% CHO diet (380 g) was significantly greater (P ≤ 0.05) than for fish fed other diets. Average harvest weight of fish fed the 19% CHO diet (347 g) was significantly greater (P ≤ 0.05) than for fish fed the 25% CHO diet (310 g). Specific growth rates (%/d) were significantly higher (P ≤ 0.05) in fish fed the 13 and 19% CHO diets than in fish fed 25% CHO diet. Feed conversion ratios for fish fed the 13 and 19% CHO diets (2.3 and 2.4, respectively) were both significantly lower (P ≤ 0.05) than in fish fed the 25% CHO diet (3.6). There were no significant differences (P > 0.05) in condition factor, protein efficiency ratio, hepatosomatic index, or liver glycogen concentration among fish fed the different experimental diets. Overall, mean blood glucose levels in fish fed the 13 and 19% CHO diets (61.0 and 71.2 mg/dL, respectively) were significantly lower (P ≤ 0.05) than in fish fed the 25% CHO diet (87 mg/dL). Histopathological examination of livers from fish fed the three diets was used to score the degree of vacuolization of hepatic tissues (0 = normal, 1 = slight, 2 = mild, 3 = moderate, and 4 = severe). Regression of vacuolization scores on dietary CHO levels was statistically significant (P ≤ 0.05) and indicated a direct positive relationship between liver vacuolization and dietary CHO level (R2 = 0.57). These data indicate that LMB grow faster and use feeds more efficiently when CHO are maintained at <20% of diet. CHO levels >20% negatively impacted liver histology, but a liver tissue analyses did not document glycogen accumulation.

Insulin Response of Largemouth Bass to Glucose, Amino Acid, and Diet Stimulation

AbstractInvestigation of the dietary requirements of largemouth bass Micropterus salmoides has intensified because of the popularity of this species. To determine commercial diets containing carbohydrate concentrations that are not detrimental to the health and survival of largemouth bass, we examined the effects of carbohydrate loads on insulin response. This study was intended to characterize the insulin response of largemouth bass to diet, glucose, and amino acids. Pellet‐trained largemouth bass were either orally stimulated with glucose, lysine, arginine, or methionine or fed a commercial pelleted diet or a “natural” diet of golden shiners Notemigonus crysoleucas, then bled over time to ascertain their insulin response. Insulin response was correlated with glucose response, the insulin responses lagging slightly behind increases in blood glucose concentration. Greater increases in blood glucose were accompanied by sharper, quicker insulin responses. Glucose (4.8 ± 0.3 ng insulin/mL) and arginine (5.4 ± 0.4 ng/mL) stimulation evoked the greatest mean insulin responses at 60 min postadministration; lysine (2.1 ± 0.3 ng/mL) also produced elevated insulin responses. The pelleted diet stimulated an intermediate response, whereas the diet of golden shiners produced the lowest insulin response. This study was intended to determine how the carbohydrate content of diets and subsequent influences on insulin response affect the health of largemouth bass. Because of confounding effects and interference from arginine and lysine in the diet, insulin response is not suitable for determining appropriate carbohydrate loads in largemouth bass diets. At this time, histological data and liver glycogen concentration should be used to determine appropriate carbohydrate loads in commercial diets.

Survival of Largemouth Bass from Populations Infected with Largemouth Bass Virus and Subjected to Simulated Tournament Conditions

AbstractMortality was measured for largemouth bass Micropterus salmoides in simulated tournaments conducted at 26°C to determine whether an easily accomplished live‐well management protocol reduced mortality. Treatment fish, which received the live‐well management protocol, were held for 8 h in live wells at 23°C with water containing more than 5 mg of dissolved oxygen/L and 0.3% salt (NaCl). Control fish, were confined for 8 h in live wells at 26°C (ambient temperature) with dissolved oxygen fluctuating from 3 to 5 mg/L and no salt, which simulated the live‐well management practices used by largemouth bass tournament anglers. Mortality after live‐well confinement was 0% for both treatment and control fish, and mortality during the first 24 h after the simulated tournaments was 2.5%. Mortality of fish observed for up to 5 d after the simulated tournaments was high for treatment fish (mean = 75%; SE = 16%) and control fish (mean = 85%; SE = 11%), and we conclude that the treatment conditions did not reduce postrelease mortality. We suggest that the unusually high posttournament mortality was related to largemouth bass virus infections.

Survival of largemouth bass, bluegill and channel catfish embryos after electroshocking

Survival to hatching was determined after electroshocking embryos of largemouth bass Micropterus salmoides, bluegill Lepomis macrochirus and channel catfish Ictalurus punctatus. Embryos at different developmental stages were exposed for 20 s to homogeneous electric fields (4–16 V cm−1) of direct current (DC) or 60 or 120 Hz pulsed direct current (PDC) in water of 100 μS cm−1 ambient conductivity. For all species, DC reduced survival of embryos at developmental stages before, during, or soon after epiboly; but survival did not differ from controls during later developmental stages. Survival of largemouth bass and bluegill was not reduced by 60 or 120 Hz PDC except for bluegill exposed at 12 h post‐fertilization. Channel catfish embryo survival was <5% when exposed to 60 or 120 Hz PDC at 8 h post‐fertilization, survival improved for embryos exposed at 67 h to 60 Hz but not to 120 Hz, and all embryos survived exposure to PDC at 150 h post‐fertilization. Exposure durations as short as 5 s resulted in <10% survival of largemouth bass during sensitive stages. All bluegill embryos aged 22 h post‐fertilization hatched prematurely after exposure to 16 V cm−1 DC, but survival was not affected. The use of PDC for electroshocking near largemouth bass and bluegill nests could reduce the negative effects on survival of these species; however, PDC can reduce survival of channel catfish embryos.

Overwinter Growth and Survival of Largemouth Bass: Interactions among Size, Food, Origin, and Winter Severity

Abstract Winter severity (temperature, duration, and photocycle), geographic origin, food availability, and initial body size likely influence growth, survival, and, therefore, recruitment of age-0 largemouth bass Micropterus salmoides. We collected age-0 largemouth bass (70–160 mm total length) from low (33°N), intermediate (40°N), and high (45°N) latitudes throughout their natural range (origin), and we subjected all three groups of fish to three experimental winters that mimicked these latitudes (N = 9 largemouth bass per treatment). Within each winter and origin, one-half of the largemouth bass were fed fish prey, whereas the remaining one-half were starved. Winter strongly influenced survival; overall survival rates in the high-, intermediate-, and low-latitude winters were 34.9, 59.4, and 61.1%, respectively (χ2 test, P < 0.05). Largemouth bass from 33°N suffered high mortality in the high-latitude winter. Across all winters, more fed fish (64.5%) survived than did starved fish (38.1%) (χ2 test, P <...

Effects of Reservoir Hydrology on Reproduction by Largemouth Bass and Spotted Bass in Normandy Reservoir, Tennessee

Age-0 largemouth bass Micropterus salmoides and spotted bass M. punctulatus were collected from Normandy Reservoir, Tennessee, 1992–1996, to evaluate effects of reservoir hydrology and hatching of shad Dorosoma spp. on hatching and first-year growth and survival of these two species. Fish were collected in cove rotenone samples in early Aug and electrofishing samples biweekly throughout the summer; hatch dates and age-specific growth for both species were determined from cove samples with sagittal otoliths. Hatching of both species ranged from early April to early Jun. Initiation of largemouth bass spawning, but not spotted bass spawning, was positively related to the first day water levels achieved full pool. Mean hatch dates of both species were positively related to the first day of full pool. Timing of spawning for both species was not related to water temperature. Largemouth bass exhibited bimodal length-frequency distributions by midsummer in two wet years and length frequencies were unimodal in dry years; spotted bass always formed unimodal length-frequency distributions. When largemouth bass exhibited bimodal length distributions, earlier hatched fish grew faster than later hatched fish. Spotted bass grew at similar rates, regardless of hatch date, every year except during 1992 when later hatched fish grew faster than earlier hatched fish. Weekly survival of largemouth bass in their first summer was positively related to reservoir water level. First-year growth of both species was not directly affected by the timing of threadfin shad D. petenense or gizzard shad D. cepedianum hatching.

Individual-based modeling of PCBs effects on young-of-the-year largemouth bass in southeastern USA reservoira

Effects of polychlorinated biphenyls (PCBs) on young-of-the-year (YOY) largemouth bass ( Micropterus salmoides) are simulated using an individual-based population model. The model simulates the daily development, growth, and survival of largemouth bass from eggs to the end of their first growing season (October 15) in a single, well-mixed box. The model was configured for southeastern USA reservoirs, mostly using data from two Tennessee River impoundments. PCBs exposure levels are expressed as tetrachlorodibenzo- p-dioxin (TCDD) concentrations in largemouth bass tissue. PCBs effects of increased mortality and reduced growth (via decreased feeding and increased metabolic rate) are imposed on modelled individuals dependent on specified exposure concentrations. Monte Carlo following fie model predictions of largemouth bass were analyzed; number density (number/ha), biomass density (kg/ha), mean length (cm), and mean condition factor ( K), all on October 15, and survivorship (fraction of eggs surviving to October 15). PCBs concentrations between 0 and 20 ppm were stimulated. Predicted bass number density and biomass density increased with increasing spawner density show a leveling off with increasing spawner density, implying density-dependence (due to bass consumption reducing prey densities) was operating. PCBs effects were apparent but small relative to natural variation in model predictions. Number density, biomass density, mean condition factor K, and survivorship all decreased, and mean length slightly increased, with increaseing PCNs levels. Predicted PCBs effects for a chronically exposed population (fewer spawners) were less at low exposure levels and greater at high exposure levels than those for an initially-healhy population. Field-based comparisons of YOY densities have a low power for distinguishing PCBs effects from natural interannual variability. While the direct effects of PCBs were relatively small. PCBs exposure may increase the risk of populations to natural and other anthropogenic stresses. Some caution should be used when short-term predictions are used to assess long-term consequences of contaminant exposure. Accurate prediction of PCBs effects require realistic representation of YOY largemouth bass growth rates and better method for estimating exposure in nature.

Effects of Cage Culture on Growth, Abundance, and Survival of Resident Largemouth Bass (Micropterus salmoides)

Growth, population size, and survival of resident largemouth bass (Micropterus salmoides) were estimated before, during, and after the cage culture of Salmo gairdneri and Ictalurus punctatus. Growth in length, length–weight relationship, and condition factor were similar among the periods; however, abundance and survival of largemouth bass increased through the 3 yr of investigation. Stomach content analyses showed that the bass fed on fishes (mostly Lepomis macrochirus), crayfish, insects, and zooplankton (predominantly entomostracans). Increase in the standing crops of L. macrochirus and entomostracans during the study periods have provided forage to the increased bass population and thus resulted in greater survival of the young and adult bass of the cage culture and postcage culture periods. Key words: largemouth bass, Micropterus salmoides, cage culture, growth, abundance, survival

Post-Stocking Survival of Largemouth Bass Reared in Raceways on an Artificial Diet

Abstract Largemouth bass (Micropterus salmoides) that were raceway-reared to a length of 13 cm on Purina Trout Chow were introduced into two 0.04-ha ponds containing fathead minnows (Pimephales promelas), to determine post-stocking survival. For comparison, two 0.04-ha ponds were stocked with largemouth bass of similar size which had been pond-reared on fathead minnows. After 27 days, both groups of bass had gained weight, but a substantially larger percentage of the pellet-fed bass had survived. The results indicated that bass reared intensively in raceways and fed an artificial diet survive and grow well when transferred to ponds, if live food is available and there is no competition from larger predators.

Effect of Sea-Water Concentration on the Reproduction and Survival of Largemouth Bass and Bluegills

(1964). Effect of Sea-Water Concentration on the Reproduction and Survival of Largemouth Bass and Bluegills. The Progressive Fish-Culturist: Vol. 26, No. 3, pp. 99-106.