Age, growth, and natural mortality of schoolmaster (Lutjanus apodus) from the southeastern United States
Ages of schoolmaster (n= 136) from the southeastern Florida coast from 1981–2015 were determined using sectioned sagittal otoliths. Opaque zones were annular, forming March–July (peaking in May–June). Schoolmaster ranged in age from 1–42 years; the largest fish measured 505 mm total length (TL) and was 19 years old. The oldest fish measured 440 mm TL. Estimated body size relationships for schoolmaster were:W= 9.26 × 10−6TL3.11(n= 256,r2= 0.95);W= 2.13 × 10−5FL2.99(n= 161,r2= 0.95);TL= 1.03FL+ 10.36 (n= 143,r2= 0.99); andFL= 0.96TL− 8.41 (n= 143,r2= 0.99), whereW= whole weight in g,FL= fork length in mm, and TL in mm. The fitted von Bertalanffy growth equation was:Lt= 482 (1 −e−0.12(t+2.79)) (n= 136). Based on published life history relationships, a point estimate of natural mortality for schoolmaster wasM= 0.10, while age-specific estimates ofMranged from 1.57–0.18 for ages 1–42.