Christopher S. Guy

Population Characteristics of Black Crappies in South Dakota Waters: A Case for Ecosystem-Specific Management

Abstract We sampled 22 populations of black crappie Pomoxis nigromaculatus from three ecosystem types (large impoundments, >40 ha; small impoundments, ≤40 ha; natural lakes) to determine the factors that influence population characteristics (recruitment, growth, size structure, and condition) in South Dakota. Recruitment variability was best correlated with the log10 of the shoreline development index (r = 0.63, df = 16) and the log10 of the watershed : lake area ratio (r = 0.89, df = 12). Mean back-calculated length at age was highly variable among ecosystems and was inversely correlated with the log10 of the catch per unit effort (CPUE; r = –0.35 to –0.69). Mean back-calculated length for all ages was positively correlated with mean relative weight (r = 0.48–0.78, df = 18-21). Proportional stock density and relative stock density of preferred-length fish were inversely correlated with log10 CPUE (Spearman correlation, rs = –0.31 to –0.83, df = 21) and were positively correlated with growth of black crap...

Stock density indices: Development, use, and limitations

Abstract The purposes of this paper are to review the development and assess the utility of stock density indices. Stock density indices, specifically proportional stock density (PSD) and relative stock density (RSD), were developed to quantify length‐frequency data. Length categories for standardized determination of stock density indices were based on percentages of world‐record length for each fish species; five‐cell length categories have been proposed for many warm‐ and coolwater fishes, but few coldwater fishes. Both seasonal patterns in sampling data and gear‐related biases can affect length‐frequency data used to determine stock density indices. Stock density indices have been correlated with population dynamics (recruitment, growth, and mortality), relative abundance, and condition for many fish species; coefficients of determination typically are low, and much of the variability in the relations is unexplained. Stock density indices for predator and prey fish populations tend to be inversely rel...

Development and Evaluation of a Standard Weight (WS) Equation for Yellow Perch

Abstract Weight-length data for 78 populations of yellow perch Perca flavescens in 20 states and 6 Canadian provinces were used to develop a standard weight (Ws ) equation. We used the regression-line-percentile (RLP) technique, which provides a 75-percentile standard, to develop the Ws relationship. The proposed equation in metric units is log10 Ws = –5.386 + 3.230 log10 L ; Ws is weight in grams and L is total length in millimeters. The English equivalent of this equation is log10 Ws = –3.506 + 3.230 log10 L ; Ws is weight in pounds and L is total length in inches. These equations are proposed for use with 100-mm (4-in) and longer yellow perch. Relative weight (Wr ) values calculated with the proposed Ws equation did not consistently increase or decrease with increasing fish length. Mean population Wr values were significantly correlated with growth and size structure of yellow perch populations, but correlation coefficients were generally low.

Structural Relationships of Largemouth Bass and Bluegill Populations in South Dakota Ponds

Abstract Spring electrofishing samples were collected from 13 small South Dakota impoundments to determine if the population structures of largemouth bass Micropterus salmoides and bluegill Lepomis macrochirus in a northern state were similar to those in more southerly waters. Largemouth bass catch per hour of electrofishing (catch per unit effort; CPUE) was inversely correlated with proportional stock density (PSD; r = –0.70, P = 0.01) and relative stock density at preferred length (RSD-P; r = –0.79, P = 0.001) for largemouth bass. Largemouth bass CPUE was positively correlated with bluegill PSD (r = 0.72, P = 0.02). Largemouth bass PSD was inversely correlated with bluegill PSD (r = –0.83, P= 0.003); bluegill PSD exceeded 60 only when largemouth bass PSD was less than 20. Bluegill PSD was inversely correlated with largemouth bass mean relative weight (r = –0.72, P = 0.02). Largemouth bass CPUE and RSD-P were significantly correlated with bluegill growth. Thus, the relationships between largemouth bass a...

Seasonal Variation in Catch Rate and Body Condition for Four Fish Species in a South Dakota Natural Lake

ABSTRACT Seasonal variation in catch rate (catch per unit effort, CPUE) and body condition (relative weight, Wr) for northern pike Esox lucius, black crappie Pomoxis nigromaculatus, yellow perch Perca flavescens, and walleye Stizostedion vitreum sampled with trap (modified fyke) nets was evaluated in Lake Madison, a natural lake in eastern South Dakota, from March through October, 1990. Seasonal variation in CPUE and Wr occurred for all fish species. Northern pike CPUE declined from spring until fall. Black crappie CPUE was highest in the spring and fall. Yellow perch and walleye CPUE peaked during the summer. Seasonal variation in mean Wrwas similar for all fish species—mean Wr declined from spring to early summer then increased until early fall. Fisheries biologists should consider seasonal variation associated with CPUE and Wr during the assessment of sampling data.

Movement Patterns of Adult Black Crappie, Pomoxis nigromaculatus, in Brant Lake, South Dakota

ABSTRACT Movement of adult black crappie (Pomoxis nigromaculatus) in Brant Lake, South Dakota was studied with ultrasonic telemetry from April through August 1991. Movement ranged from 0 to 584 m/h and was significantly different among months (P=0.0001, F=9.34, df=4) and diel periods (P=0.0013, F=5.45, df=3). Activity was greatest during April and July. Diel movement increased from evening to morning, and the least amount of movement occurred during the day; this pattern was similar for all months. In general, crappie were found in shallow waters during evening and night in the spring of the year and during day and evening in the summer. Of the seven physicochemical variables measured (i.e., water temperature, Secchi disk transparency, sky cover, wind direction, wind speed, barometric pressure, and precipitation), only barometric pressure was positively correlated with fish movement (P=0.016, F=6.435, df=12, r=0.75).

Biotelemetry of white crappies in a South Dakota glacial lake

Abstract Ultrasonic telemetry was used to determine monthly and diel movements of white crappies Pomoxis annularis in a South Dakota glacial lake, Sonic transmitters were surgically implanted in 37 adult white crappies (265–327 mm, total length; 315–530 g) at intervals from 10 April through 22 September 1992. From 15 April to 15 October, 1,712 locations were recorded for 34 of these fish. Movement (m/h; measured along the straight-line distance between successive locations) was significantly different among months (P < 0.05). Movement was highest in May (102.1 m/h) and significantly different from movements in April and June, The second highest amount of movement was in July (82.4 m/h). Other than in early spring, movement did not vary significantly among months. Depth of lake at white crappie locations differed significantly among months. White crappies were in significantly shallower lake areas in June and October than in August. Distance from shore differed significantly among months. White crappies we...

Evaluation of Largemouth Bass-Yellow Perch Communities in Small South Dakota Impoundments

Abstract Largemouth bass Micropterus salmoides and yellow perch Perca flavescens were sampled in eight small (0.9–27.9 hectares) South Dakota impoundments to evaluate community dynamics and determine whether the yellow perch can be used as a panfish for small-pond management. Largemouth bass catch per hour of electrofishing (CPUE) was positively correlated (r = 0.81, P = 0.02) with yellow perch proportional stock density (PSD = percentage of stock-length fish that are also quality length). Largemouth bass PSD was inversely correlated with yellow perch PSD (r = –0.82, P = 0.01). Mean relative weight (Wr = 100 × individual fish weight/standard weight) of yellow perch was inversely correlated (r = –0.71, P = 0.05) with relative stock density of preferred-length (RSD-P) largemouth bass (RSD-P = percentage of stock-length fish that are also preferred length). Yellow perch growth was inversely correlated with largemouth bass size structure. The highest correlation occurred between mean back-calculated length of...

Growth of Crappies in South Dakota Waters

ABSTRACT We obtained age-and-growth data from 34 black crappie (Pomoxis nigromaculatus) samples from 25 water bodies and nine white crappie (P. annularis) samples from four water bodies in South Dakota from 1990 through 1993. Mean back-calculated length for black crappie was significantly different among water body type [i.e., small impoundments (< 40 ha), reservoirs (≥ 40 ha) and natural lakes] for all ages (P ≤ 0.01). Growth was slowest in small impoundments and fastest in natural lakes. Ultimate length (L.) was significantly correlated with mean back-calculated length at age (P ≤ 0.01). Mean length at time of capture varied monthly for white crappies. Age-2 white crappies completed 71% of their growth in length during July and August.

Precision and Size Structure of Juvenile Percichthyid Samples Collected with Various Gears from Lake Texoma

Abstract We collected juvenile striped bass Morone saxatilis and white bass M. chrysops with various gears to evaluate size selectivity and the precision of mean catch per unit effort (CPUE). We used four types of trawls, horizontal and vertical gill nets, conventional electrofishing and electrofishing with a push net, cove rotenone, and bag seine. Trawling was ineffective for sampling juvenile striped bass (<30 cm total length) and white bass (<15 cm). Striped bass CPUE data were most precise for offshore and nearshore floating gill nets, and least precise for push-net electrofishing. Floating gill nets also provided relatively precise CPUE estimates for white bass. There were substantial differences in the size of fishes collected by the gears, with gill nets collecting the largest juveniles.