SCHWARTZ AND PORTER: FISHES, MACROINVERTEBRATES OFF NORTH CAROLINA 



perimental area were consistently smaller than 

 those from the commercial area (Table 4). Median 

 sediment size and texture analyses data from the 

 two areas were virtually identical (Table 3). There 

 was some indication that organic values in the 

 experimental area may be slightly higher than 

 those from the commercial area (Table 3). Car- 

 riker ( 1959) noted that growth of Mercenaria mer- 

 cenaria was faster in his low organic areas than in 

 areas with higher organic percentages. This was 

 the opposite of our findings. 



Apparently the growth of the calico scallop is 

 not related to chlorophyll a content for we noted 

 primarily little difference between chlorophyll a 

 content, regardless of sampling area (Figure 5). 



FISHES OF 

 THE CALICO SCALLOP BED 



Some 4,461 fishes belonging to 49 families and 

 111 species were collected during the 51 cruises 

 between 9 January and 23 October 1972. One ad- 

 ditional species, Scorpaena isthmensis, was added 

 to the faunal list during exploratory trips in 1971 

 and 1973. Pelagic, demersal, and benthic families 

 and species were represented in the catches (Table 

 5). Of the total fishes landed (4,392) as part of the 

 1972 scallop catches, 985 were tagged and re- 

 leased to note movements, 1,655 were analyzed for 

 food content, and 1,752 specimens were merely 

 observed and identified. Most of the 112 species 

 encountered were sporadic components of the scal- 

 lop bed either as they passed north-to-south or 

 east-to-west, depending on the season of the year. 



Of the 112 species of fishes associated with the 

 calico scallop bed, 94 or 84.0% can be considered 

 Caribbean in their main distribution and abun- 

 dance, while 7 (6.2%) were Virginian forms that 

 had moved seasonally south of the Cape Hatteras 

 barrier. Eleven species (9.8%) were those whose 

 distribution ranges extended naturally over a 

 broad north-south geographic area and could not 

 be considered northern or southern faunal compo- 

 nents. Controversy still exists whether that por- 

 tion of the shelf off North Carolina is simply a part 

 of an overall north-south temperate Virginia 

 Province faunal region (Forbes 1856) or an area 

 divided into a nearshore Virginia and offshore 

 Gulf Stream influenced Carolinian Province 

 (Gray and Cerame-Vivas 1963; Wells et al. 1964; 

 Cerame-Vivas and Gray 1966; Gray et al. 1968; 

 Bumpus 1973; Briggs 1974). Struhsaker (1969) 

 and Schwartz (in press) have shown this area to be 



rich in fishes with an overall 70:30 ratio of south- 

 ern to northern fishes, a condition far richer than 

 that of the northern Gulf of Mexico, contrary to the 

 findings of Briggs (1974). 



Some 33 species dominated the 1972 catches, of 

 which 21 species accounted for 77.1% of the fishes 

 handled: Stenotomus aculeatus (413 specimens), 

 Synodus foetens (386), Paralichthys dentatus 

 (303), Diplectrum for mosum (254), Raja eglanteria 

 (252), Orthopristes chrysopterus (249), Prionotus 

 scitulus (196), Monacanthus hispidus (174), Cen- 

 tropristes striata (122), Batistes capriscus (120), 

 Prionotus evolans (116), Hemipteronotus novacula 

 (104), Leiostomus xanthurus (104), Mustelus canis 

 (95), Lagodon rhomboides (91), Aluterus schoepfi 

 (85), Paralichthys albigutta (77), Etrumeus teres 

 (75), Urophycis regius (74), Syacium papillosum 

 (73), and A ncylopsetta quadrocellata (71). 



A few species, notably Raja eglanteria, Centro- 

 pristes striata, Ancylopsetta quadrocellata, and 

 Paralichthys dentatus, seemed to occupy the beds 

 throughout the year (Table 5). The loss of such 

 species as Prionotus evolans, Orthopristes chrysop- 

 terus, and Aluterus schoepfi from the beds was 

 evident as they moved shoreward during the 

 summer months. Mustelus canis and Urophycis 

 regius were winter components of the fauna prior 

 to their movement northward or seaward away 

 from the encroaching higher summer water tem- 

 peratures. Others, such as Diplectrum formosum, 

 Mullus auratus, and Aluterus scriptus occurred 

 during or appeared late in the summer, apparent- 

 ly transported by meanders of the Gulf Stream 

 (Webster 1961; Roe et al. 1971) from the south 

 when water conditions met their usual tropical 

 temperature requirements for existence. Rhinop- 

 tera bonasus was a good sample of a north-south 

 transient in April and August as the schools 

 moved past the area to other grounds (Schwartz 

 1965). Halieutichthys was an example of an 

 offshore species apparently moving into shallower 

 water with occasional incursions (Blanton 1971) of 

 deep ocean water onto the shelf. As expected, bot- 

 tom fishes of the families Bothidae, Soleidae, Trig- 

 lidae, and hard shell crushers of the Balistidae and 

 Tetraodontidae predominated (Table 5). The most 

 exciting captures were Letharchus velifer, Ser- 

 raniculus pumilio, Prionotus ophryas, and Scor- 

 paena isthmensis, as their capture represented 

 sizeable northward range extensions. McEachran 

 and Eschmeyer (1973) have also recently noted 

 the northward extension of S. isthmensis. 



Nineteen species were tagged for movement 



435 



