164 
Fishery Bulletin 115(2) 
Table 4 
Estimates of the von Bertalanffy growth parameters, the asymptotic length (L„ ), growth coefficient (k), and hypothetical 
age at size zero (to), and the predicted size at age, presented in fork length (FL) in millimeters, for sheepshead {Archosargus 
probatocephalus) collected from in Tampa Bay, Florida, 1993-2009 (this study); Louisiana, 1987-1988 (Beckman et al., 1991); 
northwest Florida, 1997-1998 (Dutka-Gianelli and Murie, 2001); and South Carolina, 1995-1996 (Wenner®). 
Growth parameters 
Tampa Bay 
Louisiana 
Northwest Florida 
South Carolina^’2 
Females 
Males 
Females 
Males 
Combined 
Females 
Males 
Combined 
L„ (mm FL) 
419.1 
422.5 
447.0 
419.0 
490.4 
475.7 
509.2 
505.0 
k 
0.272 
0.255 
0.367 
0.417 
0.260 
0.280 
0.230 
0.290 
^0 
-1.099 
-1.115 
-1.025 
-0.901 
-0.420 
-0.460 
-0.520 
-1.109 
Predicted size at ages (mm FL) 
0 
109 
105 
139 
1 
183 
177 
151 
160 
150 
231 
2 
239 
232 
300 
294 
229 
237 
224 
299 
3 
282 
275 
345 
337 
289 
295 
283 
351 
4 
315 
308 
376 
365 
335 
339 
329 
389 
5 
340 
334 
398 
383 
371 
373 
366 
418 
6 
359 
354 
413 
395 
398 
398 
396 
440 
7 
373 
370 
423 
403 
419 
417 
419 
456 
8 
384 
382 
431 
409 
435 
431 
437 
469 
9 
393 
391 
436 
412 
448 
442 
452 
478 
10 
399 
398 
439 
415 
458 
450 
464 
485 
11 
404 
404 
442 
416 
465 
456 
473 
490 
12 
408 
408 
443 
417 
471 
461 
481 
494 
13 
411 
411 
444 
418 
475 
486 
497 
14 
413 
414 
445 
418 
479 
491 
499 
15 
414 
416 
446 
418 
482 
495 
500 
16 
446 
419 
502 
17 
446 
419 
503 
18 
447 
419 
503 
19 
447 
419 
504 
20 
447 
419 
504 
21 
504 
22 
505 
23 
505 
24 
505 
25 
505 
26 
505 
* For the growth parameters, L„ originally presented as total length (TL; 559 mm); converted to FL, for comparison, by using 
TL-FL relationship given by Wenner®. 
^ For predicted sizes at age calculated as TL (L„-559 mm) and converted to FL, for comparison, by using TL-FL relationship 
given by Wenner®. 
areas) may have obscured differences. If sheepshead 
undergo a habitat shift from shallow nearshore waters 
into deeper waters, the growth parameters we describe 
might not indicate the age and growth of sheepshead 
in the deeper habitats. 
Regional differences in sheepshead growth param¬ 
eters may be attributed partly to population genetics. 
Within the U.S. range of this species, 2 subspecies of 
sheepshead have been reported (Caldwell, 1965). We 
analyzed A. p. probatocephalus, which occurs along the 
Atlantic coast and into the Gulf of Mexico to Stein- 
hatchee, Florida. A Louisiana study (Beckman et ah, 
1991) considered A. p. oviceps, which occurs in the Gulf 
of Mexico from St. Marks River, Florida, to Campeche 
Bank, Mexico. A study from northwest Florida (Dutka- 
Gianelli and Murie, 2001) looked at both subspecies 
(84% A. a. probatocephalus and 11% A. a. oviceps) and 
found no significant differences in growth. Anderson et 
al. (2008) concluded that molecular genetic data indi¬ 
cated a very limited genetic subdivision between the 
subspecies, despite considerable divergence in some 
morphological characters. 
In contrast, recent analyses of 24 species-specific mi¬ 
crosatellite DNA loci of both A. probatocephalus sub¬ 
species from the Atlantic (Florida to North Carolina) 
and the Gulf of Mexico (Florida and Texas), showed a 
