Atlantic croaker, continued 



down to Argentina, but is may be confused with a 

 similar species, Micropogonias furnieri (Chao and 

 Musick 1977, Hoese and Moore 1977, Fischer 1978). 



Within Study Area : The Atlantic croaker occurs from 

 Florida Bay to the Rio Grande River in Texas. It is 

 considered one of the most common bottom-dwelling, 

 estuarine fish in the northern Gulf of Mexico (Table 

 5.37) (White and Chittenden 1976, Hoese and Moore 

 1977). 



Life Mode 



Atlantic croaker are estuarine-dependent. Eggs are 

 pelagic and buoyant (Ditty and Shaw 1 994), and early 

 larvae are pelagic and planktonic. Early larvae are 

 found on the mid- to outer continental shelf, but be- 

 come generally uniform throughout the shelf. Later 

 stages become more demersal and occur in more 

 inshore to estuarine areas. Juveniles become still 

 more demersal and move into tidal creeks. Adults are 

 demersal and move between estuarine and oceanic 

 waters (Lassuy 1983, Cowan 1985, Cowan and Shaw 

 1988). 



Habitat 



Ty pe: Adults are estuarine to marine, and have been 

 collected from depths of 1 to 90 m. They appear to be 

 most abundant in mesohaline and polyhaline salinities, 

 and are rare below 10%o (Christmas and Waller 1973, 

 Wagner 1 973). Juveniles are estuarine to riverine and 

 prefer fresh to mesohaline salinities (Parker 1971). 

 Eggs and early larvae are marine, and later larvae are 

 marine to estuarine. Recently spawned larvae have 

 been collected at depths ranging from 15 to 115 m, 

 although most occur in the upper 30 m, about 20 to 200 

 km from shore (Cowan 1985, Sogard et al. 1987, 

 Cowan and Shaw 1988). Most small larvae were 

 collected near midshelf about 65-1 25 km from shore in 

 euhaline salinities. Fish three years old tend to domi- 

 nate estuaries in North Carolina while those >3 years 

 old are found mostly offshore (Ross 1988). 



Substrate : Practically all sizes of croaker beyond the 

 larval stage are associated with soft bottoms (Lassuy 

 1983). Juveniles occur over mud-sand in shallow es- 

 tuarine and tidal creek areas, i.e., fine unconsolidated 

 substrates. Adults are associated with mud-sand, 

 oyster reefs, shell and live bottoms in deeper waters. 



Physical/Chemical Characteristics: 

 Temperature - Eggs and Larvae: While eggs and newly 

 hatched larvae are found at 18-25°C, larger and older 

 larvae can be found at progressively decreasing tem- 

 peratures. Larvae have been found in temperatures as 

 low as 1 0°C in the Gulf of Mexico (Cowan 1 985, Cowan 

 and Shaw 1 988), but in the Chesapeake Bay area, they 

 are found from 0° to 24° C (Ward and Armstrong 1 980). 



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