Stellwagen Bank Final EIS and Management Plan 



Page 21 



Table 1: Macrobenthic Taxonomic Groups at 

 Georges Bank, by Biomass and Density 



Sampling data from both mud and sand reference 

 stations in Cape Cod Bay within and outside the 

 Massachusetts Bay Disposal Site (MBDS), situated 

 immediately northwest of the Stellwagen Bank study 

 area, indicate an overwhelming dominance of 

 anneUd species in both mud and sand sediments. 

 Annelids comprised between 89.6% and 95.4% of 

 macrobenthic species at mud reference stations; 

 between 85.9% and 86.1% at sand reference 

 stations (Hubbard, Penko, and Fleming, 1988). 

 Species found at these stations are listed below. 



Mud Site 



Sand Site 



Paraonis gracilis Exogone verugera 



Heteromastus filiformis Prionospio steenstrupi 



Anobothrus gracilis 

 Nicomache spp. 

 Paraonis gracilis 

 Ampharetid spp. 

 Myriochele oculata 

 Chone infundibuliformis 



Cossura longocirrata 



Spio pettiboneae 



Oligochaete spp. 



Chaetozone setosa 



Mediomastus ambiseta 



Myriochele oculata 



Trochochaeta multisetosa Astarte undata 



Prionospio steenstrupi Phloe minuta 



Thvasira flexuosa 



Aricidea quadrilobata 



Sternaspos scutata 



Maldane sarsi 



Praxillura longissima 

 Exogone hebes 

 Mediomastus ambiseta 

 Spio pettiboneae 

 Cossura longocirrata 

 Streblosoma spiralis 



Similarly, sampling conducted by NOAA's 

 Northeast Monitoring Program at two stations in 



the Gulf of Maine between 1978 and 1985 indicated 

 dominance by polychaetes at Station 35, situated 

 near the Massachusetts Bay Disposal Site location 

 (NOAA/NMFS, 1990). Seasonality of polychaetes 

 was indicated, and biomass levels were ranked 

 between 100 and 250 g/m". Polychaetes were 

 dominated by Spio Filicornis . This and other 

 polychaete species (sabelUds and nereids) provide 

 important prey for flounders. The echinoderms 

 Ctenodiscus crispatus and Molpadia oolitica were 

 also found in abundance. 



The second sampling site (Station 28), located in 

 the extreme western portion of Georges Bank, was 

 overwhelmingly dominated by echinoderms, 

 primarily two species: Brisaster fragiUs (urchin), and 

 Ophiura sp. (brittlestar). Ophuroids in particular 

 are important prey for cod and plaice. 



Typical inhabitants of the Stellwagen Bank (areas 

 primarily of sand or pebbly-sand composition) 

 include organisms adapted to loose and occasionally 

 shifting substrate, such as: 



Echinarachnius parma . common sand dollar 



Crangon septemspinosis . sand shrimp 



Lunatia heros . (carnivorous gastropod moUusk) 



Nassarius trivitattus .(carnivorous gastropod moUusk) 



Spisula solidissima . surf clam 



Astarte castanea . chestnut astarte 



Leptocuma . (cimiacean crustacean) 



Chiridotea. (isopod crustacean) 



Pagurus acadianus . Acadian hermit crab 



Ophelia , (polychaete worm) 



Goniadella . (polychaete worm) 



Clymenella . (polychaete worm) 



Heterostigma . (tunicate) 



Molgula . (tunicate) 



Haustorid and phoxocephalid amphipods . (beach 



fleas) 



In the few areas of Stellwagen Bank where 

 sediment composition is partially gravel, the 

 following invertebrate fauna may be found: 



Polymastia , (sponge) 

 Clionia . (sponge) 

 Myxilla . (sponge) 

 Balanus crenatus . (barnacle) 

 B. hameri . (barnacle) 



