There are only three species of blood flukes known in salmonids in the world. Wales (1958) described two, Sanguinicola davisi and S. klamathensis, while Meade and Pratt (1965) described Cardicola alseae.

No description available.

No description available.

Despite the long history of stocking trout and the popularity of stocked-trout fishing in Virginia, no study has investigated the use of the program nor attempted to describe anglers actively seeking stocked trout. Agencies have stocked trout in Virginia since the 1920s and today, Virginia Department of Game and Inland Fisheries (VDGIF) stocks the majority of the fish in the state, stocking over 1 million catchable-sized trout on over 180 waters. Given the expansive effort of VDGIF and the popularity of the program, VDGIF desired to understand how anglers utilize their program and who actively fishes for stocked trout. My objectives were 1) to assess catch, harvest, effort, and return-to-creel rates of stocked trout on various fishery and water body types, across seasons and number of days post-stocking in stocked waters in western Virginia, 2) to identify market segments of anglers seeking stocked trout based upon their demographic characteristics, motivations, and degree of specialization, 3) to compare satisfaction and management preferences of the market segments of anglers seeking stocked trout in Virginia and 4) to recommend stocking and management strategies that best meet the desires of stocked-trout anglers in Virginia and that produce managerially desired catch rates to the Virginia Department of Game and Inland Fisheries. I conducted on-site surveys on 17 stocked-trout waters across Virginia. Most anglers reported high levels of satisfaction with their fishing experience that day and with the program in the last 12 months. The majority of anglers caught something that day. Anglers had diverse fishing and management preferences. Stocking density did not affect catch rate on lakes nor streams. Time following a stocking event did influence catch rate and effort; anglers caught fish the quickest on the day of stocking, but catch rate remained near 1 trout per angler-hr and did not significantly differ from the day after stocking to 30 days after stocking. Catch rate positively correlated with angler satisfaction, yet the majority of the anglers were highly satisfied, even if they did not catch any fish. We identified four groups of anglers: casual anglers, consumptive-experienced anglers, avid anglers, and specialists. Social investment, experience, and fishery resource use varied among the four groups. The four groups also had differing motivations for fishing, fishing preferences, management preferences, and levels of satisfaction. Multinomial logistic regressions showed that specialization, age, catch rate, importance an angler places on catching something, and waterbody type contributed to the best model for predicting angler satisfaction. Anglers on streams typically expressed greater satisfaction than anglers on lakes. Angler satisfaction negatively correlated with the importance an angler placed on catching something. / Master of Science

Metabolic fuel use in rainbow trout (𝘖𝘯𝘤𝘰𝘳𝘩𝘺𝘯𝘤𝘩𝘶𝘴 𝘮𝘺𝘬𝘪𝘴𝘴 W.) was investigated using closed system respirometry and proximate body analysis. During short term starvation (15 days, routine activity) the utilization of protein as a substrate, as determined by respirometry, increased from 14 to 24% of total fuel supply. However, even by the end of the experiment, the contribution of protein (24%) did not approach the classically reported values for fish of between 40 and 90%. Indeed, from respirometry data, during the first quarter of the experiment lipid contributed the majority of the fuel ( >60%) while carbohydrate contributed about 20%. Thereafter, lipid and carbohydrate became essentially equivalent in importance (about 37% each). However, from proximate body analysis, a more traditional fuel mixture was found (protein, 58%; lipid, 40%; carbohydrate, 2%) suggesting the possibility that the two procedures were measuring fundamentally different parameters. Instantaneous fuel use during sustainable swimming at different speeds was investigated by respirometry using three day test periods. While protein catabolism remained constant over time, and uniform between groups, its relative contribution tended to increase with time as total M₀₂ declined with sustained swimming. Protein catabolism was highest in nonswimming fish (30-45%) and lowest in the high speed swimmers (20%); lipid was the most abundant (41-55%) fuel used in all groups at all times. In the nonswimmers and lowspeed swimmers, lipid use tended to increase slightly over time whereas in the high speed swimmers, lipid use dropped from 54 to 44%. Carbohydrate use (up to 38%) was higher than predicted by earlier literature, but decreased greatly in both the nonswimmers and low speed swimmers over the three days, whereas in the high speed swimmers the contribution increased with time. The low speed swimmers from the last set of experiments were used as controls for the final set of experiments in which another group of fish were trained for two weeks at 1.0 L·s⁻¹ prior to testing using an otherwise similar regime. Even though there was no difference in gas exchange, the make-up of the fuel mixture was different for the two groups. Protein use was significantly lower, while lipid use was higher in the trained fish. In addition, relative protein use in the trained fish was constant over the three day period, a feature found only in the the high speed swimmers of the previous experiment. A critical evaluation of the respiratory quotient is given since its use by fish physiologists has been without complete conversion from that used by the mammal physiologists. In addition, the often quoted term "fuel use" is differentiated into 𝘪𝘯𝘴𝘵𝘢𝘯𝘵𝘢𝘯𝘦𝘰𝘶𝘴 𝘧𝘶𝘦𝘭 𝘶𝘴𝘦 and 𝘤𝘰𝘮𝘱𝘰𝘴𝘪𝘵𝘪𝘰𝘯𝘢𝘭 𝘧𝘶𝘦𝘭 𝘶𝘴𝘦 since the two describe fundamentally different principles, though this has not always been recognized in the literature. / Thesis / Master of Science (MS)

Thesis / Master of Science (MS)

The gravel environment of 30 brown trout (Salmo trutta) redds and adjacent nonredd sites in two western North Carolina streams were studied during the incubation period in 1979-1980 and 1980-1981. Intragravel water temperature, dissolved oxygen concentration, and percent oxygen saturation were highly correlated with surface water measurements, indicating that intragravel water is of surface origin. Permeability ranged from 250 to 149,350 cm/hr and averaged 6,150 cm/hr. Apparent velocity varied from 0 to 1,000 cm/hr and averaged 30 cm/hr. Permeability in redds was significantly greater than at nonredd sites. No significant differences in apparent velocity were found between redd and nonredd sites. No consistent differences in permeability or apparent velocity were found between streams or over time. Permeability and apparent velocity decreased significantly with depth. Freeze cores were collected from redd and nonredd sites and divided into three 10-cm layers for analysis. Geometric mean diameter, sorting coefficient, fredle index, percent fines <2.00 mm, and percent porosity were highly variable and averaged 11.8 mm, 2.8, 4.2, 17.0 percent, and 19.0 percent, respectively. No significant differences were found among factors tested. Correlations between these gravel indices and permeability and apparent velocity were low. The gravel and intragravel environments appeared to be adequate for larval survival. Measurements did not reveal any clear trends during the incubation period. Brown trout did not by choice or redd construction appear to select or create (by redd construction) a subsurface environment different from the surrounding stream bed. / M.S.

Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 47-55). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 53-61). Also available on the World Wide Web.

Density and standing stock of brook trout within the Hazel River, Shenandoah National Park, declined sharply between 1982 and 1989. Most of the reduction occurred within the middle and lower reaches, where density of brook trout declined 66% and 920/0, respectively. This study characterized the movement, growth, and mortality of the Hazel River brook trout population in 1989-1990 and examined the role of these phenomena in the recovery of that population. Physical habitat appeared excellent throughout the stream, with adequate pools, cover, and spawning substrate in all sections. Results from visible implant tag recoveries established that the majority (60%) of adult and yearling trout were sedentary during the one year study period. Brook trout exhibiting movement tended to move upstream during the fall over relatively short distances ( < 250 m). Movements of up to 700 m (up- and downstream) were observed in less than 5% of post-juvenile trout. Young-of-the-year (YOY) trout moved more frequently than other age groups and tended to move downstream; they are probably the primary vehicle of downstream recolonization. Growth and condition of Hazel River brook trout were typical of other streams within Shenandoah National Park. Poor growth occurred during the summer months, which is typical of southeast stream trout populations. Generally, growth was higher in areas where density was lowest. Estimated mortality over summer was highest (400/0) for yearling and adult trout within the upper reaches. Despite closure of the Hazel River to angling for two years, its brook trout population remained depressed in 1989. The study demonstrated that recovery of depleted trout stocks through intrastream migration may be slow. Reasons for the continued depression of the brook trout population in the Hazel River may include predation by American eels, illegal angIer harvest, the sedentary nature of stream-dwelling trout, or a combination of these factors / Master of Science