Dominant Species
The ten
most abundant species from eight of the sampling locations are listed
in Table 5. Although differences between the Blake et al. (1993) and
Gilbert et al. (1976) samples would be expected due to differences in
sieve size, the faunal composition of most of the stations is quite
similar. The polychaetes Spio limicola, Prionospio streenstrupi, Aricidea
quadrilobata and Mediomastus californiensis are among the numerical
dominants at most of the sites. Spio limicola is the numerical dominant
at all sites listed, except for station 3, which is located farther
offshore in the Gulf of Maine. These communities appear to be fairly
stable over time (Blake et al. 1993). They also appear to be quite different
from communities observed on Georges Bank, which are dominated by amphipods
and syllid polychaetes (Maciolek and Grassle, 1987). Additionally, these
communities differ from stations of comparable depths south of Martha's
Vineyard and Nantucket (Maciolek et al. 1985; Blake et al. 1993).
Table 5. Top ten numerically dominant species at selected stations within
or near Stellwagen Bank National Marine Sanctuary boundaries.
The benthos of the regions surrounding Stellwagen Bank, and within the
Stellwagen Bank National Marine Sanctuary, constitutes a stable community
and one that may be unique to Massachusetts Bay. At the present time,
the benthic community structure of Stellwagen Bank itself has yet to
be described and quantified. This area may have a species composition
quite different from that of the surrounding areas due to high productivity
on the bank as well as differences in sediment grain-size. However,
given the unique nature of the Massachusetts Bay communities, and the
high rates of benthic-algal production (Cahoon et al. 1993) Stellwagen
Bank is also likely to have an important, interesting and unique benthic
community.
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