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The sheepshead (Archosargus probatocephalus) is common in coastal waters from the Chesapeake Bay to Texas in the United States and supports a viable recreational and commercial fishery throughout much of its range. Otoliths were extracted from 2549 sheepshead collected from 1993 through 2009 in Tampa Bay, Florida, during routine sampling by the Fisheries-Independent Monitoring program of the Florida Fish and Wildlife Conservation Commission. Sheepshead ranged in size from 107 to 524 mm fork length (FL). Age of sheepshead was estimated by counting annuli (opaque zones) in thin-sectioned sagittal otoliths. Marginal-increment analysis of sheepshead from ages 1 to 6 indicated that a single opaque ring was formed on an otolith each year between May and June. In Tampa Bay, sheephead reached a maximum age of 15 years. Males and females experienced rapid growth through age 6; growth rate decreased markedly thereafter. Although von Bertalanffy growth models were biologically similar between sexes, they were found to be statistically different (female [FL=419.1 (1-e-0.272(age+1.009))]; males [FL=422.5 (1-e-0.255(age+1.115))]). Tampa Bay sheepshead are typically smaller at a given age than those in more northern climates and not as long lived. Differences in regional growth models may be attributed to differences in mortality, ontogenetic shifts in habitat, genetic variation, or sampling design. [ABSTRACT FROM AUTHOR]

Fish species of warm-water origin appear in northeastern U.S. coastal waters in the late summer and remain until late fall when the temperate waters cool. The annual abundance and species composition of warm-water species is highly variable from year to year, and these variables may have effects on the trophic dynamics of this region. To understand this variability, records of warm-water fish occurrence were examined in two neighboring temperate areas, Narragansett Bay and Long Island Sound. The most abundant fish species were the same in both areas, and regional abundances peaked in both areas in the middle of September, four weeks after the maximum temperature in the middle of August. On average, abundance of warm-water species increased throughout the years sampled, although this increase can not be said to be exclusively related to temperature. Weekly mean temperatures between the two locations were highly correlated (r= 0.99; P<0.001). The warm-water fish faunas were distinctly different in annual abundances in the two areas for each species by year (1987-2000), and these differences reflect the variability in the transport processes to temperate estuaries. The results reveal information on the abundance of warm-water fish in relation to trends toward warmer waters in these regions. [ABSTRACT FROM AUTHOR]

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