Seasonal Energetics and Condition of Bonefish from Different Subtropical Tidal Creeks in Eleuthera, the Bahamas

Figures & data

Figure 1. Aerial photograph of the study area showing the locations of the tidal creeks (Kemps, Broad, and Starved) and the tidal embayment (Half Sound) as well as the Cape Eleuthera Institute (CEI)

Figure 2. Estimated relationships between the percentage of water and the percentage of lipids by wet mass for (a) whole body, (b) gonad, and (c) liver samples for bonefish collected at Eleuthera (see text for equations)

Table 1. Proximate composition (% water, lipids, ash, and protein by wet mass) and energy density (MG/kg) in whole-body, gonad, and liver tissues of female (F) and male (M) bonefish sampled in summer and winter in various locations in Eleuthera, the Bahamas. Values are given as the means ± SDs

Table 2. Evaluation of the variables in the general linear models to determine whether the whole-body proximate composition and energy density of bonefish is dependent on season, location, sex, or size. All significant values are designated with asterisks

Figure 3. Mean constituent analyses for (a) water, (b) lipids, (c) ash, and (d) protein in whole-body samples of bonefish collected from Broad and Kemps creeks, Half Sound, and Starved Creek in the summer (closed circles) and winter (open circles). The error bars represent standard errors. Values with different letters are significantly different (P < 0.05; bold = summer, ordinary type = winter)

Figure 4. Estimated relationships between total length and whole-body lipid content and energy density for bonefish sampled in (a) and (c) summer and (b) and (d) winter in Eleuthera. The equations of the lines in (b) and (d) are % lipids = 11.9 – 0.020 · TL and energy density = 9.01– 0.008 · TL, respectively (see text for the equations in [a] and [c] and summary statistics)

Table 3. Evaluation of the variables in the general linear models to determine whether the proximate composition of bonefish gonads is dependent on season, location, sex, or size. All significant values are designated with asterisks

Table 4. Evaluation of the variable(s) in the general linear models to determine whether the proximate composition of bonefish livers is dependent on season, location, sex, or size

Figure 5. Scatterplots of the data for the percentages of water and lipids (wet mass) versus total length for bonefish sampled in (a) and (c) summer and (b) and (d) winter in Eleuthera

Table 5. Health indices (Fulton's condition factor [K], gonadosomatic index [GSI], and liver somatic index [LSI]) for female and male bonefish collected in Eleuthera in the summer and winter. Values are means ± SDs

Table 6. Results of three-way ANOVA evaluating the influence of season, location, and sex on various health indices for bonefish. All significant values are designated with asterisks

Figure 6. Mean health indices for bonefish sampled from Broad and Kemps creeks, Half Sound, and Starved Creek. Panel (a) shows the results for Fulton's condition factor (K), panel (b) those for the gonadosomatic index (GSI), panel (c) those for the GSI disaggregated by season, panel (d) those for the liver somatic index (LSI), and panel (e) those for the LSI disaggregated by season. Summer values are represented by closed circles, winter values by open circles. The error bars represent standard errors. Values with different letters are significantly different (P < 0.05; where both summer and winter values are shown, bold letters designate the summer ones.)

Figure 7. Estimated relationship between condition factor and the whole-body percentage of lipids in bonefish (see text for equation)