Relative Abundance, Growth, and Mortality of Suwannee Bass in Four Florida Rivers

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1 North American Journal of isheries anagement 25: , 2005 Copyright by the American isheries Society 2005 DOI: / [Article] Relative Abundance, Growth, and ortality of Suwannee Bass in our lorida Rivers TIOTHY. BONVECHIO* 1 AND ICHEAL S. ALLEN Department of isheries and Aquatic Sciences, University of lorida, 7922 Northwest 71st Street, Gainesville, lorida 32653, USA RICHARD L. CAILTEUX lorida ish and Wildlife Conservation Commission, 5300 High Bridge Road, Quincy, lorida 32351, USA Abstract. In an effort to aid in the conservation of black basses, the relative abundance, growth, and mortality of Suwannee bass icropterus notius and largemouth bass. salmoides were estimated from four lorida rivers. ish were collected by electrofishing in the four rivers during 2001 and Electrofishing catch per unit effort of Suwannee bass was highest in the Wacissa River (95.1 fish/h), intermediate in the Santa e River (22.6 fish/h), and lowest in the Withlacoochee (5 fish/h) and Ochlockonee rivers (1.9 fish/h). Catch per unit effort for largemouth bass was also highest in the Wacissa River (50 fish/h), intermediate in the Santa e (19.8 fish/h) and Ochlockonee rivers (17.1 fish/h), and lowest in the Withlacoochee River (9.9 fish/h). ean total length (TL) at age across the four Suwannee bass populations was described by von Bertalanffy growth curves as TL (1 e [age ] ) for females and as TL (1 e [age ] ) for males. ean TL at age across the three largemouth bass populations was also described by von Bertalanffy growth curves as TL (1 e [age ] ) for females and TL (1 e [age ] ) for males. Suwannee bass exhibited sex-specific growth rates similar to those of largemouth bass, females experiencing more rapid growth and attaining larger sizes than males ( 1, ; P 0.01). Suwannee bass total annual mortality (A) averaged 40%, ranging from 28% to 46%. Similarly, largemouth bass total A averaged 40%, ranging from 35% to 46%. The current lorida minimum length limit on Suwannee bass directs fishing mortality almost solely to females, but estimates of fishing mortality are needed to determine whether this is a concern for black bass with a small native range. Suwannee bass icropterus notius is one of seven species of black bass. irst collected and described by Bailey and Hubbs (1949) from the Ichetucknee River, lorida, this species has the smallest distribution of the black basses (Koppelman and Garrett 2002). Until recently, the Suwannee bass was known to occur exclusively in the Suwannee, Ichetucknee, and Santa e rivers, lorida, and in the Ochlockonee and Withlacoochee rivers of lorida and Georgia (Hellier 1967; Hurst et al. 1975; accrimmon and Robbins 1975; Swift et al. 1977). However, in recent years, populations have been observed in the Wacissa (Cailteux et al. 2002a), St. arks, and Wakulla rivers of lorida (Cailteux et al. 2002b). The Wacissa, St. arks, and Wakulla populations may have been intro- * Corresponding author: tim.bonvechio@myfwc.com 1 Present address: lorida ish and Wildlife Conservation Commission, 1601 Scotty s Road, Kissimmee, lorida 34744, USA. Received August 20, 2003; accepted June 25, 2004 Published online arch 1, 2005 duced. Canfield and Hoyer (1988) reported the presence of 30 fish species in the Wacissa River and 27 species from the St. arks River, but no Suwannee bass were observed. Because of its limited range, the Suwannee bass is considered a species of special concern by the states of lorida (Gilbert 1992) and Georgia (see the Georgia Department of Natural Resources Web site, georgiawildlife.dnr.state.ga.us/content/specialconcernanimals.asp). Growth and mortality of largemouth bass. salmoides has been studied extensively in many systems in lorida across a broad range of habitats (Porak et al. 1988; Schramm and Smith 1988; Cailteux et al. 1998; Crawford et al. 1998; Allen et al. 2002), but few Suwannee bass studies appear in the literature. Growth rates of age-0 Suwannee bass were evaluated in an Alabama pond (Smitherman and Ramsey 1971). However, no estimates of growth or total mortality have been made for Suwannee bass in their native range or habitat. Suwannee bass are a relatively small black bass (Bailey and Hubbs 1949; Hurst et al. 1975) ex- 275

2 276 BONVECHIO ET AL. TABLE 1. ean SE electrofishing catch per hour (fish/h) of Suwannee and largemouth bass in the Ochlockonee, Santa e, Wacissa, and Withlacoochee rivers. The Ochlockonee and Santa e rivers were sampled in 2001 and 2002; the Wacissa River was sampled for largemouth bass in 2001 and Suwannee bass in 2002; and the Withlacoochee River was sampled in The abbreviation N stands for the number of electrofishing transects; ratio is the number of Suwannee to largemouth bass obtained. N and total length (mm) Ochlockonee Santa e Wacissa Withlacoochee Suwannee bass N All fish Largemouth bass N All fish Ratio 1:8.5 1:1 2:1 1:2 hibiting a common robustness (Bass and Hitt 1973), with larger individuals surpassing a total length (TL) of 400 mm. The current world angling record is 1.76 kg (Koppelman and Garrett 2002), caught from the Suwannee River in Currently, Suwannee bass in lorida are managed with a creel limit of 5 fish/d and a 305-mm-TL minimum length limit. Little is known about the difference in age structure between Suwannee bass populations (Cailteux et al. 2002a). Given their small native range, proper management is important for conservation of this species. The objectives of this study were to estimate relative abundance, growth, and mortality for Suwannee and largemouth bass in four lorida rivers. ethods Suwannee and largemouth bass were collected in four lorida rivers. The middle Santa e River was sampled in October 2001 and September 2002 from inside River Rise State Preserve in High Springs, lorida (29.85 N, W), to a point just south of Rum Island (29.83 N, W), encompassing 4.8 river kilometers. The Santa e River is a calcareous, spring-fed stream with fluctuating levels of submerged aquatic macrophytes and a low to moderate historical range for flow rate ( m 3 /s). The upper Ochlockonee River was sampled in November 2001 and September and October 2002 from just south of Interstate 10, near Tallahassee, lorida (30.49 N, W), northward to Old Bainbridge Road (30.59 N, W), encompassing 19.9 river kilometers. The upper Ochlockonee River is characterized as a tannic stained river, lacking submersed aquatic macrophytes (Swift et al. 1977; Cailteux et al. 2002b), and has a historical flow rate range of m 3 /s. The lower Wacissa River was sampled in April 2001 for largemouth bass and in October 2002 for Suwannee bass from an area called Hells Half Acre (30.27 N, W) down to Goose Pasture (30.22 N, W), encompassing 6.3 river kilometers. Nordlie (1990) characterized the spring-fed Wacissa River as limestone bedrock along the shore with dense growth of submersed aquatic macrophytes and a historical flow rate range of m 3 /s (Livingston and ernald 1991). In December 2002, the middle Withlacoochee River was sampled north (30.62 N, W) and south (30.50 N, W) of the State Road 150 bridge near Pinnetta, lorida, encompassing a total of 16.9 river kilometers. The middle Withlacoochee River is also a calcareous, spring-fed river with fluctuating levels of submerged aquatic macrophytes and a broad historical flow rate range (2.15 1,062 m 3 /s). Boat electrofishing was conducted with electrical output ranging from 5 to 8 A of pulsed DC. We used three boats equipped for electrofishing: two 4.9-m johnboats with either a 50-hp (1 horsepower [hp] 746 W) or 60-hp outboard and a 4.3-m johnboat with a 15-hp outboard. Sampling took place in the fall (September December) because of potential sampling biases in the summer (Pope and Willis 1996), except that largemouth bass on the Wacissa River were sampled in April Twenty-minute electrofishing transects tar-

3 SUWANNEE BASS IN OUR LORIDA RIVERS 277 geted Suwannee and largemouth bass, concurrently, except for the separate Wacissa River samples. ean electrofishing catch per hour (CPH; fish/h) for Suwannee and largemouth bass was used as an index of relative abundance in each system. Because of the similarity of the electrofishing mean catch rates, CPH for 2001 and 2002 were combined on the Ochlockonee and Santa e rivers, for comparison of CPH analyses with the 2002 samples from the Wacissa and Withlacoochee rivers. The CPH data were log 10 transformed and analysis of variance (ANOVA) was used to test for differences in relative abundance of Suwannee bass among the four rivers. The least squares means procedure (LS EANS) was used to separate the means if the ANOVA was significant. Levene s test was also used to test for homogeneity of variances in the ANOVA. All statistical analyses were conducted with SAS (SAS Institute 2000); results were considered significant when P In each river, five Suwannee bass per centimeter group less than 250 mm TL were kept, and all Suwannee bass 250 mm TL or longer up to 10 fish per centimeter group were kept. ive largemouth bass per centimeter group less than 350 mm TL and all largemouth bass 350 mm TL or longer were kept. ish were placed on ice in the field and returned to the laboratory for measurement of TL (mm) and weight (g), determination of gender, and removal of sagittal otoliths. inimizing the number of fish to be killed for study was a concern, so Suwannee bass and largemouth bass were subsampled below 250-mm TL and 350-mm TL, respectively, in cases where gender-specific growth was not expected. A larger proportion of individuals ( 250-mm TL and 350-mm TL) were kept for age analyses because of possible age-related growth differences between males and females (e.g., largemouth bass; Carlander 1977). Bayley and Austen (2002) determined catchability of largemouth bass and bluegill across a range of sizes. On the basis of their estimates, we used a minimum catchable size-group to determine what age-groups to include in the catch curves. Suwannee and largemouth bass were assigned to a 200-mm TL catchable size. Bayley and Austen (2002) found that fish larger than this did not vary greatly in their catchability. We assumed that Suwannee bass catchability would be similar to that for largemouth bass. If at least 60% of the fish in an age-group were assigned a catchable size, that year-class was kept in the catch curve. If less than 60% of the fish were above the catchable size or there were fewer than three fish in the age-group (Ricker 1975), then the year-class was deleted from the catch curve. Age was estimated from the annuli on the sagittal otoliths (Hoyer et al. 1985; Crawford et al. 1989; Buckmeier and Howells 2003). These previous studies validated the formation of one annulus per year for otoliths on largemouth bass. We assumed that rings on Suwannee bass otoliths were annuli, similar to the situation with largemouth bass. The annuli on otoliths from all fish were counted by observing the whole otolith under a microscope; otoliths from fish older than age-0 were sectioned for verification, identical to Allen et al. (2003). Two independent readers were used when estimating the age of the fish and if a discrepancy occurred between the two readings, a third reader was used to resolve the age of the fish or the otolith was discarded. To remain consistent and potentially increase precision, the same three readers were used for the duration of the study. We used gender-specific growth curves to fit the mean TL at age separately for each Suwannee and largemouth bass population. Subsampled ages at the fixed intervals (i.e., five per cm group) could cause biased estimates of mean TL at age, especially if the length frequency distributions are not symmetrical (Bettoli and iranda 2001). ean TL at age estimates were obtained from the subsampled ages extrapolated to the whole sample according to methods of DeVries and rie (1996) and Bettoli and iranda (2001). In some cases, immature reproductive structures prevented determination of gender in small individuals; 50% of such fish were assigned as males and 50% as females. We fit von Bertalanffy growth models (Ricker 1975) to each Suwannee and largemouth bass population, gender, and sample years, using nonlinear regression (Procedure NLIN; SAS 2000). ean TLs at age for the four populations of Suwannee bass and three populations of largemouth bass were then averaged to compare potential gender differences across populations, respectively. Growth curves were not extrapolated past the maximum age obtained in the samples. Von Bertalanffy growth curves were then fit through the overall means for each species and gender across the populations. The gender-specific growth curves were fit to age-9 and -10 for male Suwannee and largemouth bass, respectively, and age-12 for females of both species. The TL-to-age relationship was evaluated by using analysis of covariance (ANCOVA) to test for

4 278 BONVECHIO ET AL. TABLE 2. Predicted mean total length (TL [mm]) at age for males () and females () for Suwannee bass in four lorida rivers and largemouth bass in three lorida rivers. Predictions are from von Bertalanffy growth equations for each population. issing values indicate that no fish were collected for that age and gender; N is the number of fish aged. ean TL at age ish aged Age 1 Age 2 Age 3 Age 4 Age 5 Age 6 River Year N Suwannee bass Ochlockonee Santa e Wacissa Withlacoochee Largemouth bass Ochlockonee Santa e Withlacoochee differences in growth rates between the genders of Suwannee bass across all rivers. Individual fish were used in this analysis, and both TL and age data were log 10 -transformed before the ANCOVA was conducted. Because the ANCOVA used all age data combined across rivers, the influence on the test was weighted by sample size at each river. However, low sample sizes at some rivers precluded system-specific tests, and the pooled-data test provided an among-river comparison of potential gender-specific growth rates for Suwannee bass. Assumptions of normality, homogeneity of variance, and linearity were assessed by using PROC UNIVARIATE and inspection of the residuals. An age length key (Ricker 1975) was used to estimate the age frequency of subsampled Suwannee and largemouth bass through extrapolation to the entire length frequency (Ricker 1975). Catch curves were constructed by regressing the log e number of fish against age (Ricker 1975), and the slopes estimated instantaneous total mortality slope (Z) and total annual mortality (A 1 e Z ; Ricker 1975). We removed year-classes from the catch curves if there were fewer than three fish in the age frequency. Genders were combined for all mortality estimates for each species. Results A total of 260 electrofishing transects were conducted on four systems during the study (Table 1). ost transects (94%) were sampled for 20 min in both years, but transects other than 20 min (10 16 min) were included in the analyses (Table 1). Because we attempted to obtain an adequate age sample for each population, the total number of fish and the number of electrofishing transects (20 min) differed across systems (Table 1). A total of 1,052 Suwannee bass were collected, and age was estimated for 662. A total of 1,370 largemouth bass were collected, and age was estimated for 960. The size range of all Suwannee bass populations combined ranged from 67 to 402 mm TL, whereas largemouth bass ranged from 48 to 590 mm TL. Electrofishing CPH of Suwannee bass in the Wacissa River was high (95.1 fish/h) compared with that of the Santa e River (22.6 fish/h), the Withlacoochee River (5 fish/h), and the Ochlockonee River (1.9 fish/h; Table 1). ean logtransformed CPH for Suwannee bass differed among the four rivers ( 3, ; P 0.01) and the least squares means test revealed log-transformed CPH of Suwannee bass in all four rivers differed from each other (t ; all P 0.01). Similarly, electrofishing of largemouth bass in the Wacissa River (50 fish/h) exceeded that in the Santa e River (19.8 fish/h), the Ochlockonee River (17.1 fish/h), and the Withlacoochee River (9.9 fish/h; Table 1). The catch rate ratio of Suwannee:largemouth bass differed across systems (Table 1). Largemouth bass outnumbered Suwannee bass 8.5:1 at the Ochlockonee River and 2:1 at the Withlacoochee River, whereas Suwannee bass outnumbered largemouth bass 2:1 at the Wacissa River, and the ratio was relatively even at the Santa e River. aximum age was similar for Suwannee bass and largemouth bass. Suwannee bass ages ranged

5 SUWANNEE BASS IN OUR LORIDA RIVERS 279 TABLE 2. Extended. ean TL at age Age 7 Age 8 Age 9 Age 10 Age 11 Age 12 River Suwannee bass Ochlockonee Santa e Wacissa Withlacoochee 369 Largemouth bass Ochlockonee Santa e Withlacoochee from 0 to 9 years for males and from 0 to 12 years for females (Table 2). Largemouth bass ages ranged from 0 to 10 for males and from 0 to 12 for females (Table 2). Various sample sizes of agedetermined fish were obtained across rivers and species, and some samples had missing ages (Table 2). ean TL at age across the four populations for Suwannee bass and three populations for largemouth bass was described by von Bertalanffy growth curves, the females of both species attaining a larger L than the males (see igure 1 for the parameters of the growth curves). Analysis of covariance revealed that female Suwannee bass grew more rapidly than males: log 10 TL 0.433(log 10 age) for females, log 10 TL 0.346(log 10 age) for males ( 1, ; P 0.01). The Suwannee bass from each river revealed differences in gender among size groups. or age-determined Suwannee bass 305 mm TL or longer, 100% of the Wacissa (N 21) and Withlacoochee River (N 13) fish, as well as 88% of the Santa e River (N 51) fish were female. Conversely, only 60% of Ochlockonee River Suwannee bass 305 mm TL or longer were female. or all age-determined populations combined, the sex ratio of Suwannee bass between 200 and 305 mm TL was 1:1. Conversely, for all age-determined populations combined, 87% of the Suwannee bass 305 mm TL or longer were female. Total annual mortality estimates were similar between largemouth and Suwannee bass. Average instantaneous total mortality (Z) was 0.51 for Suwannee bass and total annual mortality (A) was 0.40 for the three populations with adequate samples (igure 2). Estimates of Z and A were averaged from two sample years on the Santa e River (igure 2). Estimates of Z and A were not possible for the Ochlockonee River because of inadequate sample sizes. or Suwannee bass, A ranged from 28% on the Withlacoochee River to 46% on the Santa e River (igure 2). or largemouth bass, mean Z was also 0.51 and total A was also 0.40 for the two populations with adequate samples (from the Santa e and Ochlockonee rivers). Estimates of Z and A were not possible for largemouth bass on the Withlacoochee River because the sample sizes of larger fish ( 200 mm TL) were inadequate. Age samples for largemouth bass were not collected on the Wacissa River. Discussion Electrofishing catch rates of Suwannee and largemouth bass observed on the Ochlockonee, Santa e, and Wacissa rivers were similar to those reported in other studies (Schramm and aceina 1986; Cailteux et al. 2002a). Length frequencies of Suwannee bass from the Santa e, Wacissa, and Withlacoochee rivers indicated the populations were mostly small individuals; between 86% and 91% were less than 300 mm TL. Similar to Cailteux et al. (2002a), we also observed a larger proportion of individuals greater than or equal to 300 mm TL (33 45%) in the Ochlockonee River over two sample years. Suwannee bass exhibited gender-specific growth rates similar to those of largemouth bass (Schramm and Smith 1988), the females exhibiting more rap-

6 280 BONVECHIO ET AL. IGURE 1. Von Bertalanffy growth curves obtained from predicted mean total length (TL)-at-age estimates for Suwannee bass collected in four lorida rivers and largemouth bass collected in three lorida rivers during 2001 and id growth and attaining larger sizes than the males. According to the average growth curves across rivers, the average female Suwannee bass recruited to the 305-mm-TL minimum size limit in 3.4 years but males did not reach the size limit until 5.4 years. Gender-specific differences in growth were much more significant if the fast-growing Ochlockonee River population was removed from the growth curves; in the remaining populations, females took 3.6 years to reach the size limit and males did not reach the size limit until 6.3 years. emales generally attained older ages than males, the age of the oldest female being 12 years and of the oldest male 9 years. We did not obtain any male Suwannee bass on the Wacissa or Withlacoochee River that surpassed the 305-mm-TL size limit and for populations of all ages combined. Subsequently, most male Suwannee bass (except the Ochlockonee populations) did not attain harvestable size ( 305 mm) in lorida. These gender-specific differences in growth rate have implications for setting minimum length limits. Under the 305-mm-TL minimum length limit currently in place, fishing mortality is directed almost entirely on female Suwannee bass on all systems except the fast-growing population at the Ochlockonee River. We did not obtain genderspecific estimates of fishing mortality, but the fact that female Suwannee bass attained older ages than males in this study suggests that fishing mortality on female fish was not severely truncating their age frequency. Nevertheless, fishery managers should consider that a 305-mm length limit could potentially change population sex ratios of Suwannee bass if fishing mortality becomes high. Total annual mortality rates were identical for

7 SUWANNEE BASS IN OUR LORIDA RIVERS 281 IGURE 2. The top four panels depict catch curves of the log e transformed number of fish at each age plotted against the ages of Suwannee bass collected at the Santa e River, lorida, in 2001 and 2002 and at the Wacissa and Withlacoochee rivers, lorida, in The bottom four panels depict catch curves of the log e transformed number of fish at each age plotted against the ages of largemouth bass collected at the Santa e and Ochlockonee rivers in 2001 and The linear regression equations are also shown. Ages were not included in the catch curve if sample size was low ( 3 fish). Age-0 and age-1 fish were not included because they might not have fully recruited to the gear. The standard error (SE) for each slope coefficient is shown. Low sample sizes precluded mortality estimates for Suwannee bass on the Ochlockonee River in 2001 and 2002 and for largemouth bass on the Wacissa and Withlacoochee rivers in 2002.

8 282 BONVECHIO ET AL. Suwannee bass and largemouth bass from the Ochlockonee and Santa e rivers in this study and were quite similar to those for largemouth bass in other lorida rivers, which averaged 53% and ranged from 44% to 73% (Allen et al. 2002). Genderspecific total mortality rates for Suwannee bass indicate the potential for higher fishing mortality of females and should be considered in future studies. Combining tagging studies with total mortality estimates might also be useful to differentiate between fishing and natural mortalities for Suwannee bass. Currently, Suwannee bass and largemouth bass have the same minimum length limit, in part because of angler difficulty in identifying the species. In the future, studies to estimate gender-specific mortality rates should be conducted if overharvest of Suwannee bass becomes a concern. Assessment of mortality and growth rates such as this study should aid in the conservation of this rare black bass species and help develop future management strategies. Acknowledgments This research was funded by the Wildlife oundation of lorida, Inc. P. Cooney, K. Dockendorf, G. Kauffman, and K. Bonvechio, as well as many other University of lorida and WC personnel, provided help with the field sampling and laboratory processing,. This manuscript is part of the lorida Agricultural Experiment Station Journal Series R References Allen,. S., W. Sheaffer, W.. Porak, and S. Crawford Growth and mortality of largemouth bass in lorida waters: implications for use of length limits. Pages in D. Philipp and. S. Ridgway, editors. Black bass: ecology, conservation, and management. American isheries Society, Symposium 31, Bethesda, aryland. Allen,. S., K. I. Tugend, and. J. ann Largemouth bass abundance and angler catch rates following a habitat enhancement project at Lake Kissimmee, lorida. North American Journal of isheries anagement 23: Bayley, P. B., and D. J. Austen Capture efficiency of a boat electrofisher. Transactions of the American isheries Society 131: Bailey, R.. and C. L. Hubbs The black basses (icropterus) of lorida, with description of a new species. University of ichigan Occasional Papers of the useum of Zoology 516:1 40. Bass, D. G., Jr., and V. G. Hitt Sport fishery ecology of the Suwannee and Santa e rivers, lorida, report II. Distribution and life history aspects of the Suwannee bass, icropterus notius, Bailey and Hubbs. Report to lorida Game and resh Water ish Commission, Tallahassee. Bettoli, P. W., and L. E. iranda Cautionary note about estimating mean length at age with subsampled data. North American Journal of isheries anagement 21: Buckmeier, D. L., and R. G. Howells Validation of otoliths for estimating ages of largemouth bass to 16 years. North American Journal of isheries anagement 23: Cailteux, R. L., W.. Porak, S. Crawford, and L. L. Connor Differences in largemouth bass food habits and growth in vegetated and unvegetated north-central lorida lakes. Proceedings of the Annual Conference Southeastern Association of ish and Wildlife Agencies 50(1996): Cailteux, R. L., J. J. Nordhaus, and D. A. Dobbins. 2002a. The Suwannee bass of the Wacissa and Ochlockonee rivers, lorida. Pages in D. P. Philipp and. S. Ridgway, editors. Black bass: ecology, conservation, and management. American isheries Society, Symposium 31, Bethesda, aryland. Cailteux, R. L., D. A. Dobbins, and R. Land. 2002b. Evaluating sportfish and catfish populations in northwest lorida lakes and streams. lorida ish and Wildlife Conservation Commission, Completion Report, Tallahassee. Canfield, D. E., Jr., and. V. Hoyer The nutrient assimilation capacity of the Little Wekiva River. inal Report to the City of Altamonte Springs, University of lorida, Gainesville. Carlander, K. D Handbook of freshwater fish biology, volume 2. Iowa State University Press, Ames. Crawford, S., W. S. Coleman., and W.. Porak Time of annulus formation in otoliths of lorida largemouth bass. North American Journal of isheries anagement 9: Crawford, S., W.. Porak, D. J. Renfro, and R. L. Cailteux Age and growth of trophy largemouth bass in lorida. Proceedings of the Annual Conference Southeastern Association of ish and Wildlife Agencies 50(1996): DeVries, D. R., and R. V. rie Determination of age and growth. Pages in B. R. urphy and Willis, editors. isheries techniques, 2nd edition. American isheries Society, Bethesda, aryland. Gilbert, C. R Rare and endangered biota of lorida, volume II. ishes. University Press of lorida, Gainesville. Hellier, T. R., Jr The fishes of the Santa e River system. Bulletin of the lorida State useum Biological Sciences 2:1 46. Hoyer,. V., J. V. Shireman, and. J. aceina Use of otoliths to determine age and growth of largemouth bass in lorida. Transactions of the American isheries Society 114: Hurst, H., G. Bass, and C. Hubbs The biology of the Guadalupe, Suwannee, and redeye basses. Pages in H. Clepper, editor. Black bass bi-

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