POLYCHAETOUS ANNELIDS OF THE DELAWARE BAY REGION 



Peter Kinner^ and Don Maurer^ 



ABSTRACT 



Between 1967 and the present, 1,303 quantitative and 887 qualitative samples were taken from 10 

 different areas in the Delaware Bay region. Four major areas were examined: Delaware Bay proper, 

 two smaller bays, the coastal areas, and offshore on the midcontinental shelf A total of 125 species of 

 polychaetous annelids representing 34 families and 88 genera were identified. The greatest number of 

 species (95) was collected at the offshore stations, which also had the highest genus to species ratio 

 (1:1.6). Delaware Bay samples contained 83 species and the coastal areas 74 species. The smallest 

 number of species was collected in the small bays (33). The dominant species on the midcontinental 

 shelf were: Goniadella gracilis, Lumbrinerides acuta, Spiophanes bombyx, Exogone hebes, and E. 

 verugera. In Delaware Bay, Heteromastus fUiformis, Nephtys picta, and Glycera dibranchiata were 

 collected most regularly. The polychaete fauna of three epifaunal assemblages (mussel bed, serpulid 

 "reef," and oyster beds) were also examined. Increasing numbers of Nephtys picta, Glycera dibran- 

 chiata, and Heteromastus fUiformis were associated with sediments containing increasing amounts of 

 silt-clay in Delaware Bay. Lumbrinerides acuta and Goniadella gracilis were associated with poorly 

 sorted coarse sediments ( >1 mm) on the continental shelf. A zoogeographic analysis revealed this area 

 to be the southern limit of the range for 11 species and the northern limit for 3 species. The Delaware 

 fauna was more closely related to the northern fauna than to the southern fauna. A summary is given 

 for some recent taxonomic changes in species present in the coastal waters of the eastern United States. 



This account was prepared to review the composi- 

 tion, distribution, and general ecology of 

 polychaetous annelids in the Delaware Bay re- 

 gion. The most comprehensive treatment of 

 polychaetes from the northeast Atlantic off the 

 United States was presented by Pettibone ( 1963a). 

 She reported 183 species from 29 families; cited 

 records of depth, sediment preference, and repro- 

 ductive condition; and collated and reviewed the 

 works of Webster, Benedict, Verrill, Treadwell, 

 Moore, Hartman, and others. Since then, she has 

 published research on paraonids, spionids, 

 sigalionids, pilargids, and nereids from the north- 

 east Atlantic (Pettibone 1962, 1963b, 1965, 1966, 

 1970a, b, 1971). Hobson (1971) has added some 

 additional records to the polychaetes of New En- 

 gland. Deepwater polychaetes from the western 

 Atlantic Ocean, including New England, were de- 

 scribed by Hartman (1965) and Hartman and 

 Fauchald ( 1971). Gosner (1971) prepared a key for 

 invertebrates from Cape Hatteras to the Bay of 

 Fundy and listed 213 species of polychaetes. Pratt^ 



'College of Marine Studies, University of Delaware, Lewes, 

 Del.; present address: Normandeau Associates, Inc., 15 Picker- 

 ing Avenue, Portsmouth, NH 03801. 



^College of Marine Studies, University of Delaware, Lewes, 

 DE 19958. 



^Pratt, S. D. 1973. Benthic fauna./n S. B. Saila (editor). Coast- 

 al and offshore environmental inventory, Cape Hatteras to Nan- 

 tucket Shoals, 5:1-70. Univ. R.I., Mar. Publ. Ser. 2. 



reviewed the literature on polychaetes from Nan- 

 tucket to Cape Hatteras. 



In nearshore waters off North Carolina, 

 Hartman (1945) reported 104 species of 

 polychaetes and presented information on tube 

 building, reproductive maturity, and faunal as- 

 sociations. Wells and Gray (1964) listed 110 

 species from the Cape Hatteras area and mainly 

 emphasized the zoogeographic affinities of the 

 polychaetes. Day et al. (1971) analyzed distribu- 

 tional patterns of the benthic fauna across the 

 continental shelf off Beaufort, N.C., from the shore 

 to 200 m in depth. Later, Day ( 1973) reported 229 

 species of polychaetes from the shelf study and 

 prepared a guide for the species known from North 

 Carolina. More recently, Gardiner ( 1975) provided 

 a key to 163 species of errant polychaetes from 

 intertidal and shallow subtidal zones of North 

 Carolina. Wass (1972) compiled a valuable list of 

 the benthic fauna of Chesapeake Bay, including 

 polychaetes, with annotated records of ecological 

 data. 



The earliest work on polychaetes in the Dela- 

 ware Bay area was conducted by Leidy ( 1855) and 

 Webster ( 1880, 1886). Polychaetes associated with 

 oyster beds in Delaware were discussed by Maurer 

 and Watling (1973). Wells (1970) and Curtis 

 (1975) described reefs of "sand coral" (Sabellaria 

 vulgaris) from the shores of Delaware. 



Manuscript accepted June 1977. 



nSHERY BULLETIN: VOL. 76, NO. 1, 1978. 



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