Table 2. Juvenile ladyfish growth rates and size-at-age 1 based on length-frequency analysis in Florida waters by location.
For comparison purposes, the direct method growth rate determined by captive rearing (Levesque, 2014) is shown along with available ladyfish age and growth estimates from previous studies (Alikunhi & Rao, 1951; Gehringer, 1959; McBride et al., 2001). The overall mean growth rate and size-at-age 1 was estimated by pooling the data for each location. The y-intercept of the exponential regression formula was corrected to 21 mm SL to better reflect natural growth (shaded cells). Locations are as follows: Indian River Lagoon (IRL), Tampa Bay (TB), Volusia County (VC (Tomoko River Basin, Ponce de Leon Inlet, and Mosquito Lagoon complex)), and Little Manatee River (LMR). Data for TB and LMR was reported by Levesque (2014).
| Age determination method | Growth rate (mm/day) | Size-at-age 1 (mm SL) | ||||||
|---|---|---|---|---|---|---|---|---|
| TB | IRL | VC | LMR | TB | IRL | VC | LMR | |
| Present study: length-frequency analysis (data pooled) | 1.11 | 1.25 | 0.2947 | 1.04 | 403.6 | 457.5 | 107.6 | 380.9 |
| 0.9101 | 0.4356 | 0.2356 | 0.3882 | 332.2 | 156.0 | 80.0 | 141.7 | |
| Levesque (2014) | 0.8134 | 296.9 | ||||||
| Alikunhi & Rao (1951) | 0.78 | 284.7 | ||||||
| Gehringer (1959) | 0.63 | 229.9 | ||||||
| McBride et al. (2001) | 0.5479–0.8219 | 200–300 | ||||||