Sauger Stizostedion Canadense Research Articles

Life History Attributes of Fishes along the Latitudinal Gradient of the Missouri River

Abstract Populations of two short-lived species (emerald shiner Notropis atherinoides and sicklefin chub Macrhybopsis meeki) and three long-lived species (freshwater drum Aplodinotus grunniens, river carpsucker Carpiodes carpio, and sauger Stizostedion canadense) were studied in the Missouri River to examine spatial variations in life history characteristics across a latitudinal and thermal gradient (38°47′N to 48°03′N). The life history characteristics included longevity (maximum age), the rate at which asymptotic length was approached (K from the von Bertalanffy growth equation), the mean back-calculated length at age, and growth rates during the first year of life (mm/degree-day and mm/d). The mean water temperature and number of days in the growing season averaged 1.3 times greater in the southern than in the northern latitudes, while degree-days averaged twice as great. The longevity of all species except freshwater drum increased significantly from south to north, but the relationships between maxim...

Growth rate responses of Missouri and Lower Yellowstone River fishes to a latitudinal gradient

Growth rate coefficients estimated for channel catfish Ictalurus punctatus, emerald shiners Notropis aherinoides, freshwater drums Aplodinotus grunniens, river carpsuckers Carpiodes arpio and saugers Stizostedion canadense collected in 1996–1998 from nine river sections of the Mssouri and lower Yellowstone rivers at two life‐stages (young‐of‐the‐year and age 1+ years)were significantly different among sections. However, they showed no river‐wide latitudinal trend except for age 1+ years emerald shiners that did show a weak negative relation between growth and both latitude and length of growing season. The results suggest growth rates of fishes along the Missouri River system are complex and could be of significance in the Management and conservation of fish communities in this altered system.

Growth rate responses of Missouri and Lower Yellowstone River fishes to a latitudinal gradient

Growth rate coefficients estimated for channel catfish Ictalurus punctatus, emerald shiners Notropis aherinoides, freshwater drums Aplodinotus grunniens, river carpsuckers Carpiodes arpio and saugers Stizostedion canadense collected in 1996–1998 from nine river sections of the Mssouri and lower Yellowstone rivers at two life-stages (young-of-the-year and age 1+ years)were significantly different among sections. However, they showed no river-wide latitudinal trend except for age 1+ years emerald shiners that did show a weak negative relation between growth and both latitude and length of growing season. The results suggest growth rates of fishes along the Missouri River system are complex and could be of significance in the Management and conservation of fish communities in this altered system.

Hooking Mortality of Saugers in the Tennessee River

Abstract We assessed hooking mortality of saugers Stizostedion canadense in two Tennessee reservoirs by holding fish overnight in a net-pen. We also attached radio tags equipped with a mortality switch to 19 saugers to document survival. Rates of gas bladder overinflation and foul-hooking using common terminal gear were estimated. The mortality rate for saugers observed in the net-pen was only 4% (3 of 74). Seventeen of 19 radio-tagged saugers were located and 15 were alive 12 d later (12% mortality). Although we could not detect a statistical relation between mortality and gas bladder overinflation, depth of capture was weakly related to the occurrence of gas bladder overinflation. When we caught saugers using the terminal gear most common in these fisheries (a bucktail jig tipped with a minnow and equipped with a trailing treble hook), equal numbers of fish were caught by the jig hook and stinger hook. Despite the fact that 42% of all the saugers we caught were foul-hooked, blood flowed from the primary...

Host Fish Suitability for Glochidia of Ligumia recta

Abstract In the early 1900s several hosts were identified for the black sandshell Ligumia recta. Recent attempts to propagate juvenile L. recta with two of the reported hosts (bluegill Lepomis macrochirus and largemouth bass Micropterus salmoides) have produced inconsistent results and few juveniles. We conducted this study to determine which of the reported hosts or other fish hosts were the most suitable for glochidial metamorphosis. The duration of glochidial metamorphosis varied among seasons. Despite similar water temperatures, juveniles metamorphosed sooner and over a shorter period of time in the spring than early fall; the modal day of metamorphosis differed by 78 d. Relatively few juveniles were recovered from bluegill and largemouth bass in three trials. White crappie Pomoxis annularis and black crappie P. nigromaculatus were marginally suitable hosts. Although glochidia encysted on all hosts, >10× more juveniles metamorphosed on sauger Stizostedion canadense compared to other hosts tested.

Relations between Physicochemical Factors and Abundance of Fishes in Tributary Confluences of the Lower Channelized Missouri River

We sampled fish from seven tributary confluences in the lower channelized Missouri River from June 1996 through July 1998 to examine the influence of physicochemical factors in the Missouri River and tributary confluences on the abundance of fishes in tributary confluences. Twenty-six species and one hybrid were collected during the course of the study, but 10 species (river carpsucker Carpiodes carpio, goldeye Hiodon alosoides, sauger Stizostedion canadense, common carp Cyprinus carpio, shortnose gar Lepisosteus platostomus, freshwater drum Aplodinotus grunniens, channel catfish Ictalurus punctatus, gizzard shad Dorosoma cepedianum, white crappie Pomoxis annularis, and smallmouth buffalo Ictiobus bubalus) composed 90% of the fish collected. Catch per effort (log10[(number of fish/100 m2) + 1]) of fishes was significantly greater in early spring (March 1997) and summer (June 1996) than in winter (December 1996 and January 1997) samples. Multivariate ordination partitioned physicochemical factors into two discrete principal components (PC) describing (PC 1) water temperature in the Missouri River and tributary confluences, and (PC 2) Missouri River turbidity, Missouri River discharge, maximum depth in tributary confluences, and turbidity in tributary confluences. Catch per effort of fishes in the tributary confluences was significantly related (R2 = 0.47, P < 0.0001) to PC 1 and PC 2 scores. Catch per effort was curvilinear along PC 1, but linear along PC 2 in the multiple regression model. Our results indicate that tributary confluences provide favorable habitat for several species in the lower channelized Missouri River. However, use of these habitats is strongly influenced by spatial and temporal changes in physicochemical factors in the Missouri River and tributary confluences and may be related to feeding, resting, and reproduction.

Relative Survival and Contribution of Saugers Stocked in the Peoria Pool of the Illinois River, 1990–1995

Abstract Numbers of sauger Stizostedion canadense declined in the Peoria Pool of the Illinois River from the 1970s to the 1990s. Stocking was evaluated as a means of supplementing natural reproduction in the pool. Marked fry were stocked in 1991–1994 (20–176/ha), and marked fingerlings were stocked in 1990–1995 (<1–20/ha). In 1990, fingerlings with a mean total length of 44 mm were stocked in June, and 92-mm fingerlings were stocked in September and October. Relative survival was 4.9:1 in favor of the 44-mm fingerlings. During 1991–1994, relative survival averaged 440:1 for stocked fingerlings (39–61 mm) versus fry. From 1990 to 1995, contribution of stocked saugers to the year-classes averaged 33.9% at age 0. Because of the immigration of wild saugers into Peoria Pool and emigration of stocked and wild fish to other pools, contributions of stocked saugers to individual year-classes decreased each year subsequent to stocking. Mean contribution of stocked saugers at harvestable ages (age 2 and older) was 9...

Irregularly Shaped Otoliths from Saugers Prevent Back-Calculation of Length at Previous Ages in Wyoming

Abstract We collected otoliths from saugers Stizostedion canadense in Boysen Reservoir, Bighorn Reservoir, and the Bighorn River in Wyoming to evaluate age and growth. All otoliths in our samples (264 fish) were irregularly shaped, and the irregularities became more pronounced with increasing age of the fish. Age estimates with irregular otoliths were possible, but back-calculation of length at previous ages was not possible as a result of radically inconsistent lengths of radii. It should not be assumed that otoliths can be used for back calculation of length at age among all stocks of sauger. The assumption of regular otolith formation within a stock should be tested before obtaining samples of otoliths for age and growth assessment.

Movement of Saugers in the Lower Tennessee River Determined by Radio Telemetry, and Implications for Management

Abstract Since 1979, abundances of sauger Stizostedion canadense have declined in the Tennessee River system. Reasons for this decline may include overharvest, loss of spawning habitat, and low recruitment due to extreme flows. The purpose of this study was to investigate the movements of saugers following winter concentration below Pickwick Dam, Tennessee. Thirty-seven saugers were implanted with radio transmitters directly below Pickwick Dam and were tracked between December 1992 and June 1993. Four saugers moved upstream through the locks at Pickwick Dam: the remaining fish stayed within the first 30 km of the tailwater throughout the spawning season. Three areas below Pickwick Dam were identified as possible March prespawn staging sites. After April 1, saugers in the tailwater area began a rapid downstream migration to the main basin of Kentucky Lake. Some fish moved downstream more than 200 km in less than 10 d in this semiclosed system. Movements encompassed four states (Kentucky, Tennessee, Mississ...

Communications: Use of Cellulose Acetate Electrophoresis to Rapidly Screen Sauger Broodstock for Sauger–Walleye Hybrids

Abstract To maintain the genetic integrity of their product, hatchery managers and culturists often need to rapidly screen fish that are intended as broodstock for hybridization with closely related species. During March 1995 and 1996, we evaluated the use of cellulose acetate electrophoresis to screen wild saugers Stizostedion canadense from the Peoria Pool of the Illinois River for hybridization with walleyes S. vitreum. Seven of 372 fish (1.9%) in 1995 and 30 of 733 fish (4.1%) in 1996 that had been identified as saugers, based on external morphology and skin pigmentation, were subsequently identified by electrophoresis as sauger–walleye hybrids and were excluded from the breeding program. In addition, polymorphisms at the phosphoglucomutase locus PGM-1* were identified among Illinois River saugers. Cellulose acetate electrophoresis allowed rapid (<30 min) discrimination of saugers from hybrids and promises to be a highly efficient system for screening potential broodstock in a hatchery environment.

Angler Exploitation of Anchor-Tagged Saugers in the Lower Tennessee River

During the winters of 1992 and 1993, 1,083 saugers Stizostedion canadense were captured, tagged with numbered Floy anchor tags, and released in the headwaters of Kentucky Lake below Pickwick Dam, Tennessee. Saugers were tagged over a 4-week period in early 1992 and a 3-week period in late 1992 and early 1993. All fish tagged within a week were considered to be a separate tag group. A monetary reward, ranging from US$5 to $100, was offered for the return of each tag with information on when and where each fish was caught. Overall exploitation (harvest) rates, adjusted for tag loss but not for nonreporting, were 32% in 1992 and 36% in 1992–1993. Group-specific exploitation rates were highest for the first group tagged in each year. A linear model explained variation in group-specific exploitation rates as a function of the number of days between tagging and 15 March each year (P < 0.01; r2 = 0.90). The linear model predicted that exploitation would exceed 50% for saugers reaching the Pickwick Dam tailwater by 1 December each year. Although over 85x1 of all tag returns came from the 30-km Pickwick Dam tailwater in both years, some tagged fish passed through dams and were caught throughout the lower 500 km of the Tennessee River.

Development of Condition and Length-Categorization Standards for Saugeye

ABSTRACT Weight-length data for 32 (N=3,371) saugeye (walleye Stizostedion vitreum x sauger Stizostedion canadense hybrids) populations from eight states were used to develop a standard weight (Ws) equation. We used the regression-line-percentile technique, which provides a 75th-percentile standard, to develop the equation. The proposed Ws equation is log10 Ws(g) = −5.692 + 3.266 log10TL(mm), and the English equivalent is log10 Ws(lb) = −3.760 + 3.266 log10TL(in). The saugeye Ws equation is valid for fish ≥ 170 mm. The proposed Ws equation was used to calculate relative weight (Wr) values for individual fish from each population to test for length-related biases. A significant relationship between total length and Wr was observed in 18 of the 32 populations. Ten populations had negative slopes while eight had positive slopes. There was no significant difference in the occurrence of positive and negative slopes (X 2=0.22, P≥0.50); therefore, no length-related biases were evident for the populations used in...

Incidence of Sport Fishes in the Commercial Fish Catch from Kentucky Lake, Kentucky and Tennessee

On-board observers accompanied commercial fishermen on Kentucky Lake and recorded the occurrences of sport fishes in gill-net, bait-line, and hoop-net catches. Sport fishes constituted 0.5% of the total catch on bait lines, 0.1% in hoop nets, and 3.9% in gill nets. The most common incidental sport species caught were freshwater drum Aplodinotus grunniens and small yellow bass Morone mississippiensis on bait lines and sunfishes Lepomis spp. in hoop nets. The percentage of sport fishes in gill nets decreased as mesh size increased. Sauger Stizostedion canadense and white crappie Pomoxis annularis were the most common species in gill nets and constituted 92% of the incidental sport-fish catch. We estimated an incidental sport-fish catch in gill nets of 2.1 fish/1,000 m of net, whereas commercial fishermen reported 0.7 fish/1,000 m. On the basis of our estimates of incidental catches from all commercial gears, we concluded that the capture of sport fishes at the extant fishing intensity did not pose a threat to sport-fish populations.

Influence of River Stage on Shoreline Electrofishing Catches in the Upper Mississippi River

Abstract The numbers of fish and fish species caught per unit of electrofishing effort along main-channel shorelines in pool 13 of the upper Mississippi River were inversely related to water level. Four species contributed predominantly to the relation between catch rate and water level: Bluegill Lepomis macrochirus; freshwater drum Aplodinotus grunniens; white bass Morone chrysops; and sauger Stizostedion canadense. There was no relation for common carp Cyprinus carpio or short-head redhorse Moxostoma macrolepidotum.