Waccamaw Drainage Fishes 21 



from the Pee Dee provides further evidence of past connections between 

 the two drainages and suggests a faunal separation of the Waccamaw 

 from the Pee Dee. We suggest that populations of E. f fusiforme were 

 probably present in the Little Pee Dee system (as in the Cape Fear and 

 Waccamaw) before the uplift of the Cape Fear Fault. Etheostoma f 

 barratti from the Pee Dee then invaded the Lumber via the Little Pee 

 Dee, replacing the nominate subspecies. There was possibly little or no 

 opportunity for such upstream dispersal of E. f. barratti into the Wac- 

 camaw because of salinity barriers, and therefore the populations of E. 

 f fusiforme persisted. 



Only one known connection between the Waccamaw and Cape 

 Fear rivers presently exists. A series of man-made canals, dug to 

 improve tree farm drainage, connects Honey Island Swamp (Juniper 

 Creek tributary) with Dans Creek of the Cape Fear drainage and Big 

 absence Creek which drains into Lake Waccamaw (Fig. 1). Only a 

 limited number of species should be able to negotiate the small, shallow 

 and often stagnant canals, thus limiting substantial faunal exchange. 

 The undescribed Elassoma was recently collected in one of these canals 

 just east of Lake Waccamaw, which suggests the possibility that it may 

 have gained access to the Big Creek system via the canals from Juniper 

 Creek. This may explain of the species from areas west of the Wac- 

 camaw River and other tributaries of the river (apart from Juniper 

 Creek and Big Creek) even where habitat appears suitable. Northward 

 expansion of its range would be possible through the canal system into 

 the Cape Fear drainage. Collecting in adjacent Cape Fear drainages has, 

 however, provided no specimens. 



According to Jenkins et al. (1972), lowland endemics or exclusively 

 shared forms are not common on the Central Atlantic Slope. The Wac- 

 camaw has at least five of these. Etheostoma perlongum and Menidia 

 extensa are Waccamaw endemics. Fundulus waccamensis is either 

 endemic to the Waccamaw or shared with Lake Phelps (coastal Albe- 

 marle drainage), pending taxonomic decisions. The undescribed Elas- 

 soma is probably shared between the Waccamaw and Savannah drain- 

 ages (F. C. Rohde, pers. comm.). The undescribed Noturus is represented 

 by two forms within the Waccamaw drainage; specimens from Lake 

 Waccamaw represent a population superficially distinct from the Wac- 

 camaw River population and may represent another Waccamaw 

 endemic. The form present in the Waccamaw River is also found in 

 rivers of the lower Pee Dee and Cape Fear drainage (Jenkins and 

 Palmer 1978; Jenkins, pers. comm.). 



In summary, the Waccamaw drainage is unique among small cen- 

 tral Atlantic coastal drainages in having a highly diversified fish fauna 

 including endemic and exclusively shared forms. The Waccamaw and 

 Little Pee Dee systems once extended farther north into the inner Coast- 

 al Plain and Piedmont. These streams were beheaded by the uplifting of 



