Largemouth bass and black crappie thrive best in 

 lentic waters of natural lakes, bayous, open river flood- 

 plains, ponds, and large impoundments. In most areas 

 they show a preference for habitats of low turbidity 

 that support a moderate growth of aquatic vegetation 

 (Emig 1966, Goodson 1966). In Louisiana, however, 

 both species may be found in some turbid rivers, lakes, 

 ponds, and bayous. 



Adult black crappie feed on a variety of items, in- 

 cluding insects, crustaceans, fishes and plants. In a 

 South Carolina reservoir, insects were the most impor- 

 tant food item consumed (Stevens 1959), while black 

 crappie from the Atchafalaya Basin fed throughout the 

 year on insects, plants, fishes and crayfish (Bryan et al. 

 1975). Studies about the habits of black crappie or 

 largemouth bass in the Chenier Plain are lacking. 



Freshwater areas of the Chenier Plain support size- 

 able populations of largemouth bass and black crappie. 

 Both species are locally abundant in marsh ponds, bay- 

 ous, and canals, where salinities average less than 

 0.5%o (Carver 1965, Turnver 1966. Lantz 1970, 

 Manuel 1971, Crandell et al. 1976). Largemouth bass 

 are more salinity tolerant and survive better in shallow 

 water (less than 1 meter) than black crappie (Morton 

 1973, Adkins and Bowman 1976, Tarver and Savoie 

 1976). The most favorable coastal habitats appear to 

 be shallow, interconnected systems with gradually 

 sloped shorelines and moderate growths of emergent 

 and/or submergent vegetation. 



Standing crops of 39.5 kg/ha and 36.1 kg/ha (35.3 

 lb/a and 32.2 lb/a) are estimated for black crappie and 

 largemouth bass respectively in the lower Atchafalaya 

 Basin (Sabins 1977). These values compare favorably 

 with standing crops recorded for the two species in 

 large impoundments in Texas (Turner 1966). Esti- 

 mated standing crops of less than 1 kg/ha were re- 

 corded for both species in brackish waters of the 

 Rockefeller Refuge (Adkins and Bowman 1976). 



Both largemouth bass and black crappie are char- 

 acteristically predatory feeders. Month-old fry of the 

 two species feed on small pelagic zooplankters, primar- 

 ily copepods and cladocerans (Emig 1966, Goodson 

 1966). Older juveniles take larger pelagic prey such as 

 larval or aduh diptera (chironomids), ephemeropterans, 

 amphipods, and other decapods. By the time they reach 

 10 cm (4 in) in length, largemouth bass and black 

 crappie begin to feed on a variety of prey fishes (Emig 

 1966, Goodson 1966, Levine 1977). 



Juvenile largemouth bass (21 to 40 mm, or 0.8 to 

 1.6 in, in total length) in the Atchafalaya Basin fed 

 upon corixids, copepods, dipterans, mysid shrimp, and 

 cladocerans (Levine 1977). Information on food habits 

 of juvenile black crappie in Louisiana is lacking. 



Foods consumed by adult largemouth bass are less 

 varied than those consumed by young bass. Most stu- 

 dies indicate that fishes and macrocrustaceans are the 

 principal foods, but aquatic insects, reptiles, amphibi- 

 ans, and even small mammals are occasionally eaten 

 (Emig 1966, Heidinger 1975). Macrocrustaceans (cray- 

 fish, blue crab, river and grass shrimp) are commonly 

 found in stomachs of Louisiana largemouths (Darnell 

 1958, Lambou 1961, Bryan et al. 1975). Largemouth 

 bass found in the Atchafalaya Basin exhibit seasonal 

 feeding cycles; crayfish are primarily consumed during 

 high water (December to May), whereas fishes consti- 

 tute the bulk of the diet during low-water periods. 



Largemouth bass and black crappie spawn in the 

 spring when water temperatures approach 1 5° C (Good- 

 son 1966, Heidinger 1975). In the Atchafalaya Basin, 

 spawning occurs primarily in March through May at 

 temperatures ranging from 19° Cto 14°C (Bryan et al. 

 1975). Spawning is reported to occur over a variety of 

 substrates from gravel and sand to roots and aquatic 

 vegetation. SOt bottoms are apparently avoided (Emig 

 1966, Goodson 1966). Relatively hard, muddy bottom 

 substrates of interior bayous, lakes, and swampy flood- 

 plains are probably the principal spawning grounds in 

 the Atchafalaya Basin. Typically, spawning occurs in 

 waters ranging in depth from 15 cm (6 in) to 1.5 m 

 (5 ft) (Bryan et al. 1975, Heidinger 1975). 



Both species spawn in nests prepared by the 

 male. Nests of the largemouth bass are usually located 

 in protected areas and are generally spaced a minimum 

 of 2 m (6.6 ft) apart (Heidinger 1975). 



Although largemouth bass and black crappie are 

 relatively tolerant of a wide range of environmental 

 variables (Emig 1966, Goodson 1966), these species in 

 Louisiana coastal waters may be most adversely affected 

 by saltwater instrusion and higli turbidity. Coastal oil 

 and gas development activities have been reported to 

 cause fish kills (Manuel 1971). 



5.5.5 ATLANTIC CROAKER (Micropogon undula- 

 tus) and SPOT (Leiostomus xanthurus) 



Atlantic croaker and spot are estuarine-dependent 

 species. Planktonic larvae migrate from spawning areas 

 in the Gulf of Mexico to nursery grounds in coastal es- 

 tuaries from November to April (Herke 1971. Parker 

 1971, Arnoldi et al. 1973, Sabins 1973.Tarbox 1974). 

 Here they develop into juveniles. Later, maturing juve- 

 niles leave the nursery grounds and migrate to the lower 

 reaches of the estuaries. Most return to the Gulf in the 

 fall. 



Spot and Atlantic croaker migrate each fall 

 from the lower estuaries and Gulf shorewaters to near 

 the edge of the continental shelf After spawning, most 

 adults return to the nearshore Gulf or lower estuaries. 



Atlantic croaker and spot are common in the near- 

 shore Gulf of Mexico and adjacent coastal bays, lakes, 

 and estuaries (Moore et al. 1970, Parker 1971, Perret et 

 al. 1971). Although adults of both species are some- 

 times found in the upper reaches of estuaries, most pre- 

 fer the higher salinity of the nearshore Gulf or adjacent 

 estuarine areas (Gunter 1945, White and Chittenden 

 1976). During the fall spawning season, the adult popu- 

 lation concentrates closer to the edge of the continental 

 shelf 



256 



