Northeast Gulf Science Volume 12 Article 10 Number 1 Number 1 11-1991 Distribution and Abundance of Nearshore Fishes in the Anclote River Estuary, West-Central Florida Stephen T. Szedlmayer Auburn University DOI: 10.18785/negs.1201.10 Follow this and additional works at: https://aquila.usm.edu/goms Recommended Citation Szedlmayer, S. T. 1991. Distribution and Abundance of Nearshore Fishes in the Anclote River Estuary, West-Central Florida. Northeast Gulf Science 12 (1). Retrieved from https://aquila.usm.edu/goms/vol12/iss1/10 This Article is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf of Mexico Science by an authorized editor of The Aquila Digital Community. For more information, please contact [email protected]. Szedlmayer: Distribution and Abundance of Nearshore Fishes in the Anclote Riv Northeast Gulf Science Vol. 12, No. 1 November 1991 75 DISTRIBUTION AND ABUNDANCE sive patches of seagrasses (Thalassia OF NEARSHORE FISHES testudinum, Syringodium filiforme, Halo­ IN THE ANCLOTE RIVER ESTUARY, dule wrightii, Halophila engelmannii, Rup­ WEST-CENTRAL FLORIDA pia maritima), mangroves, and oyster bars. Station 2, was a mesohaline habitat Fish species use estuarine areas as located 6.5 km from the mouth of the nurseries for their young (Gunter 1967). Anclote River. This station was character­ This facet of west Florida estuaries has ized by lack of rooted aquatic vegetation long been suggested (Reid 1954; Kilby and a shoreline with extensive stands of 1955; Springer and Woodburn 1960; Sykes black rush, Juncus roemerianus. Station and Finucane 1966), and subsequent trawl 3, was an oligohaline habitat located surveys have supported this phenomenon 9.6 km from the river mouth. This station (Livingston et a/. 1976; Weinstein et a/. was also characterized by lack of rooted 1977). Previous studies have concentrated aquatic vegetation, but shoreline vegeta­ efforts in more coastal or open bay waters tion was more typical of fresh waters, of the west Florida coast. West Florida including cattails Typha spp., and bald shallow estuarine habitats accessible cypress Taxodium distichum. only to seining or block nets have re­ Surface salinity and temperature ceived less attention (Subrahmanyam and measurements were made with a tem­ Drake 1975; Livingston 1975; Naughton perature compensated refractometer and and Saloman 1978; Subrahmanyam and mercury thermometer. Specimens were Coultas 1980; Price and Schlueter 1985; collected with a 1.5 mm mesh, 6.3 x 1.8 m Thayer et a/. 1987; Sogard et a/. 1987; seine net. A preliminary sample of 13 Sogard eta/. 1989). In addition, in littoral seine hauls per station in February 1980 waters where one would expect the revealed that species accumulation smallest size distributions, few studies in curves leveled off at eight seine hauls, west Florida estuaries used small and this number per station was used (<4 mm) mesh sizes (Price and Schlueter throughout the study. Collections were 1985; Thayer et a/. 1987). made every two weeks, from 26 March to The present study examines a pre­ 24 October, 1980, for a total of 361 seine viously unsampled "nearshore" fish com­ hauls (23 missing due to weather). Seine munity along the salinity gradient of the locations were chosen to maximize vari­ Anclote River estuary on the west-central ation in substrate and were repeated at coast of Florida. Sampling was designed the same locations throughout the study to capture the smallest nursery recruits period, except that distance from mean and resident fishes through the use of a high water level varied according to tidal fine (1.5 mm) mesh seine. stage. The seine was stretched parallel to the shore, 9.0 m from the water's edge, MATERIALS AND METHODS and the ends were simultaneously pulled to shore. The length of the seine was The Anclote River estuary is located 6.3 m with an effective sampling length of on the west-central coast of Florida be­ 4.5 m, thus, approximately 40m2 were tween latitudes 28°09.!..28°13'N and sampled per seine. longitudes 82°47.!..82°51W. Three stations Fish were preserved in the field with were sampled in the Anclote River estuary 10% seawater-formalin and changed to (Fig. 1). Station 1, was a polyhaline habitat 70% isopropyl alcohol after 24 hours. located at the mouth of the Anclote River. Individuals were identified, counted, and This station was characterized by exten- standard lengths measured in the labora- Published by The Aquila Digital Community, 1991 1 Gulf of Mexico Science, Vol. 12 [1991], No. 1, Art. 10 76 Short papers and notes Figure 1. Anclote River estuary sampling sites, Tarpon Springs, Florida. tory. Transient species were defined as 1981). those that complete their life cycle out­ side the estuary, and were assigned RESULTS juvenile or adult status from published lengths (Jones et at. 1978; Johnson 1978). Salinity averaged 30±2.7 Sd ppt and Total and species abundances (num­ ranged 22-34 ppt at station 1, 18±5.4 Sd bers + 1) I seine were transformed by ppt and 6-25 ppt at station 2, and 7 ± 4.3 base-10 logarithm. When assumptions of Sd ppt and 2-15 ppt at station 3. During normality (Kolmogorov-Smirnov test) and the sampling period from March to homogeneity (Bartlett-Box F-test) were October, 1980, the salinity gradient be­ met, parametric two-way analysis of tween stations always exceeded 4 ppt. At variance (2-way ANOVA) was used to test all three stations water temperature in­ for station, date, and interaction effects. creased from 23°C in March to 35°C in After significance was determined (0.05 July, then decreased to 25°C in October. level), a Tukey multicomparison test was There was little difference (<2°C) in tem­ used to identify particular differences. If perature among stations during any one conditions of normality and homogeneity sampling. were not met after transformations, a non­ Station 1 yielded the highest number parametric Kruskai-Wallis analysis of of species (37) and mean total abundance 2 variance (KW-2-way ANOVA) was used to of fishes (447 ± 1006 Sd/40 m ); station 2 test for significance (0.05 level; Zar 1984). yielded the lowest species (24) and abun­ 2 Multispecies distribution patterns were dance values (60± 193 Sd/40 m ); and examined by multidimensional scaling station 3 yielded intermediate species (30) (Schiffman et at. 1981; Field et a/. 1982). and abundance values (176±561 Sd/ 2 Species abundance data were root-root 40 m ). Abundance estimates were signif­ transformed and Manhattan-metric dis­ icantly different among stations (Fig. 2). tance used in the analysis. Iterations were Seasonally, only the highest abundance 2 stopped when Young's stress for succes­ collection date (791.4/40 m , 17 Jul), was sive iterations did not show improvement significantly different from the two lowest 2 greater than 0.000001 (Schiffman et at. collection dates (86.7/40 m , 13 Aug; https://aquila.usm.edu/goms/vol12/iss1/10 2 DOI: 10.18785/negs.1201.10 Szedlmayer: Distribution and Abundance of Nearshore Fishes in the Anclote Riv Northeast Gulf Science Vol. 12, No. 1 November 1991 77 2ooo w z w en 1500 ........ w u z <J: 1000 Clz :J ca <J: z <J: w ~ Figure 2. Mean total abundance/40m2 by station and date of nearshore fish species from the Anclote River estuary, Florida. Different letters denote significant differences among stations and among dates. There was also a significant interaction effect, not depicted (2-way ANOVA; 0.05 level). 2 6'1.7/40 m , 18 Sep; Fig. 2). In addition, summer-fall) the Anclote nearshore system there was a significant interaction effect was dominated by those species iden­ on mean total abundance between station tified as residents: M. beryl!i(la (78.'1% of and date (2-way ANOVA). total number), A. mitchil!i (10.5%), c. The estimated abundances of Meni­ variegatus ('1.0%), Gobiosoma bosci 1 dia beryllina , Lagodon rhomboides, (0.8%), Gambusia affinis (0.6%), and Leiostomus xanthurus, Cyprinodon vari­ Microgobius gu/osus (0.6%). Eight species egatus, and Eucinostomus argenteus, identified as transients, made up less showed significant station, date, and inter­ than 7% of the total abundance. Common action effects (KW-2-way ANOVA; Table '1, (>0.5%) transients included: L. rhom­ date and interaction effects not shown). boides (2.'1%}, L. xanthurus (1.8%), Brevo­ There were also several other patterns: ortia patronus ('1.0%), E. gula (0.9%), and station effect (Strongy/ura marina, Fun­ E. argenteus (0.7%). Also, juvenile stages dulus simi/is, and Poecilia /atipinna), date of all species were collected, confirming effect (F. grandis), interaction effect the nursery role of the Anclote River (Anchoa m itchilll), date and interaction estuary (Table '1). effects (Mugi/ cepha/us), and station and Changes in dominance occurred by date effects (Syngnathus scovef!J). During station and date. Menidia beryl/ina, the sampling period of this study (spring- dominated all months at station '1; April, May, and June, at station 2; and May 'Silvers ides were the most abundant taxon and iden­ through October at station 3 (Fig. 3). tified as Menidia beryl/ina, but may be a complex of M. beryl/ina and M. peninsu/ae (Chernoff eta/. Leiostomus xanthurus dominated stations 1981). 2 and 3 in March. Anchoa mitchilli domi- Published by The Aquila Digital Community, 1991 3 Gulf of Mexico Science, Vol. 12 [1991], No. 1, Art. 10 78 Short papers and notes Table 1. Species abundance pooled by date /40 m' at stations 1, 2, and 3 Anclote River estuary, Florida. Different letters denote significant difference among stations for particular species (KW·2·way AN OVA, 0.05 level), R =resident, T =transient species, J =juvenile, and A= adult.