During migration, this species is observed along 

 road shoulders, in vacant lots, or even on lawns (Palmer 

 1962). Rice field-pasture rotation is especially suitable 

 habitat for cattle egrets in central Louisiana (Ortego et 

 al. 1976). Although the availability of nesting habitat 

 may be hmited in some areas, the recent general in- 

 crease in the number of cattle egrets indicates that 

 plentiful habitat is available. For example, nesting 

 mortality of only 8% was documented in Florida 

 (Jenni 1969). An increase in pasture habitat in the 

 Chenier Plain could be beneficial to this species. 



5.3.7 REDDISH EGRET (Dichromanassa rufescens) 



Reddish egrets are year-round residents, but their 

 numbers are lower in winter than in summer (Palmer 

 1962, Lowery 1974a). Daily flights to and from resting 

 and feeding areas or nesting areas are typical. Reddish 

 egrets are rarely seen far from the Gulf or large coastal 

 estuaries. They are found in moie saline areas than 

 any other wading bird of the Chenier Plain. 



Reddish egrets hop and run actively after prey in 

 shallow, often muddy water. Food consists mostly of 

 fishes, frogs, tadpoles, and crustaceans (Bent 1927, 

 Palmer 1962). 



Portnoy (1977) found no reddish egrets nesting in 

 the Chenier Plain, but a few nests were found in black 

 mangrove communities in southeastern Louisiana. 

 Human disturbances, as reported by Anderson (1978), 

 sometimes cause nesting failures. 



5.3.8 GREAT EGRET (Casmerodius albus) 



Great egrets reside year-round on the Chenier 

 Plain, but numbers are relatively low in the winter. 

 Post-nesting dispersal is common (Byrd 1978). Daily 

 movements consist of flights to and from resting or 

 nesting grounds to foraging areas. During nonnesting 

 seasons, great egrets at Avery Island, Louisiana, return 

 to roost about 1 hour before sunset and leave individu- 

 ally after sunrise (Weise 1976). Small groups fly to or 

 from nesting colonies throughout the day during the 

 nesting season. At Avery Island, these flights were 

 often longer than 3 km (2 mi) (Weise 1976). In North 

 Carolina, they averaged at least 15 km (9 mi) (Parnell 

 and Soots 1978). 



The great egret, because of its white color, large 

 size, widespread distribution, and abundance, is one of 

 the most conspicuous birds of the Chenier Plain. Like 

 most herons, it feeds primarily in shallow water. This 

 species is larger and has longer legs than most herons; 

 consequently, it often is found in deeper water than 

 the other species. The great egret uses all the aquatic 

 habitats of the Chenier Plain. 



Great egrets usually do not feed in large groups, 

 but in Mexico, Gladstone (1977) found feeding assem- 

 blages of 125 to 150 birds. Food includes insects, crabs, 

 crayfish, g variety of fishes, frogs, toads, snakes, lizards, 

 rodents and small birds. 



Great egrets are especially conspicuous at their 

 nests, which are frequently atop the highest woody 



vegetation or highest site in the area (Portnoy 1977). In 

 mixed-species colonies they tend to nest in open or 

 exposed areas (Burger 1978, McCrimmon 1978). 

 Portnoy ( 1 977) found 1 colonies in the Louisiana Che- 

 nier Plain, which represented 19.4% of the breeders in 

 the study area. Great egrets nest early, with the peak of 

 incubation occurring in late March. Incubation begins 

 after the first egg is laid (Maxwell and Kale 1977). 



Imhof (1976) reported that this species is de- 

 clining because of habitat destruction, water pollution, 

 and insecticide contamination. Nestlingmortalityisoften 

 due to competition among the nestlings for food (Pratt 

 1970). In California, nesting success has recently de- 

 creased, probably because of organochlorine poison- 

 ing (Ohlendorfet al. 1978). 



5.3.9 SNOWY EGRET (Egretta thula) 



Snowy egrets are present year-round in the Che- 

 nier Plain, but most of the breeders migrate south 

 during the winter (Lowery 1974a). Post-nesting disper- 

 sal, as far as 320 km (198 mi), is common (Ryder 

 1978). Daily movements consist of flights between 

 feeding areas and resting or nesting areas. In the breed- 

 ing season in North Carolina, these flights probably 

 average at least 15 km or 9 mi (Parnell and Soots 1978). 



Although snowy egrets are most abundant in im- 

 pounded and natural fresh marsh areas of Louisiana, 

 they can be found in all aquatic and marsh habitats, es- 

 pecially near the coast, where they feed on small fishes, 

 crustaceans, and worms (Palmer 1962). They feed in 

 shallow open water, actively pursue prey, and often ex- 

 hibit specialized feeding behavior (Jenni 1969). 



The species nests early in the spring in fresh and 

 salt marshes (Palmer 1962) or, rarely, in brackish 

 marshes. Snowy egrets usually build nests at lower 

 levels in woody vegetation than do great egrets (Port- 

 noy 1977, Burger 1978). Incubation begins after the 

 first egg is laid (Maxwell and Kale 1977). 



Like all aquatic birds, snowy egrets are threatened 

 by chemical contamination of aquatic habitats. 



5.3.10 LOUISIANA HERON (Hydranassa tricolor) 



The Louisiana heron is primarUy a bird of salt 

 marshes, but it occasionally uses fresh marshes. It is 

 predominanatly a summer resident species in the Che- 

 nier Plain. The few individuals that remain throughout 

 the winter are inversly related in number to the severity 

 of the winter weather. Daily movements consist mostly 

 of flights between resting or nesting areas and feeding 

 areas. In Nortlr Carolina, these flights probably average 

 15 km (9 mi) in the nesting season (Parnell and Soots 

 1978). Young are fed 4 to 5 times a day (Rodgers 

 1978). 



Louisiana herons eat insects, fishes, amphibians, 

 and other small aquatic organisms (Imhof 1976). Bent 

 (1927) reports that Louisiana herons eat more fish 

 than other wading birds. They are primarily solitary 



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