Mississippi Hackney and Hackney (1976) considered the Mottled Duck a resi- 

 dent of Mississippi that breeds only in remote coastal marshes. Nests have been 

 found at Claiborne, Lakeshore, and on the west side of Saint Louis Bay (all in 

 Hancock County), where adults of the species are most frequently reported. Eggs 

 have been found from 4 April through 1 July (Hackney and Hackney 1976). 



Louisiana Mottled Ducks breed in large numbers in the Louisiana coastal 

 marshes. Although some birds are resident, others, sometimes most of the popu- 

 lation, apparently move southward into Texas or Mexico to winter (Lowery 1974). 

 Allen and Perry (1980) examined the gonads of 195 birds obtained in southwest- 

 ern Louisiana and concluded that the peak reproductive activity of females oc- 

 curred about 23 April, two weeks later than males. Bateman (_in Bellrose 1976) 

 estimated that 39% of the Louisiana population breeds in freshwater marsh, 32% 

 in marsh intermediate between fresh and brackish water, 10% in brackish and sa- 

 line marshes, and 9% on agricultural land. Early fall populations are thought 

 to contain 75,000 to 120,000 birds. 



Texas The Mottled Duck is a resident along the Texas coast where it is 

 locally common to uncommon; a few breeding records are also known from farther 

 inland. Breeding has been recorded from mid-March to August (Oberholser 1974). 

 Maximum breeding densities occur between Sabine Lake and Galveston Bay (Single- 

 ton 1953). Stuzenbaker (iji Bellrose 1976) estimated that early fall populations 

 contain 60,000 to 100,000 birds. 



SYNOPSIS OF PRESENT DISTRIBUTION AND ABUNDANCE 



Breeding/ Winter This species is a year-round resident in central and 

 southern Florida, which harbors about one-fifth to one-sixth of the total popu- 

 lation of the species (Bellrose 1976); it is uncommon in the coastal marshes of 

 Alabama and Mississippi, but locally common in coastal Louisiana and Texas where 

 most of the rest of the species breeds. It also breeds south to Tampico and 

 Tamaulipas. Data given in Bellrose (1976) indicate that the total breeding 

 population is 140,000 to 200,000 birds and that early fall populations are 

 about 250,000 to 300,000 birds. Palmer (1976a), on the other hand, reported 

 mid-winter inventories for the conterminous United States of 66,000 to 81,200 

 birds for the period 1968-1970. In winter some birds move farther south into 

 Mexico to as far south as Veracruz; within the United States they reach their 

 peak abundance along the Texas coast (Map 12). 



Migration Most Florida Mottled Ducks are essentially non-migratory but 

 some disperse short distances. Fifty-one (63.0%) of 81 birds banded at vari- 

 ous sites in Florida were recovered 10-270 mi (16-434 km) from the banding 

 site, but most (71.4%) were recovered within 49 mi (79 km) of where they were 

 released (Fogarty and LaHart 1972). Palmer (1976a) noted that thousands of the 

 western race winter in Mexico. Other non-breeding birds in Texas wander inland 

 (Oberholser 1974) and eastward into Louisiana (Bellrose 1976). 



HABITAT 



Nesting Stieglitz and Wilson (1968) reported that Mottled Duck nests on 



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