ECOLOGICAL STUDIES IN SOUTH BENFLEET CREEK 291
Ecological Studies in South Benfleet Creek with
Special Reference to the Amphipod Genus
Corophium
By J. M. Gee, B.A.*
This paper is an account of the work done on some ecological
aspects of South Benfleet Creek. A description of the Creek
is given in the Introduction and a brief account of the methods
vised in the second section. The ecology of the most important
species found in the Creek is described. The Creek is most
interesting with regard to the distribution of the two species of
Corophium found there, one of which, Corophium arenarium, is
a relatively rare species. It has been found that the composition
of the substratum, and associated factors such as water content,
is the dominant factor in determining the distribution of the
two species of Corophium and of the other two most important
species, Nereis diversicolor and Scrobicularia plana. The import-
ant distinctions between the habitat of Corophium volutator and
Corophium arenarium have also been worked out.
INTRODUCTION
Benfleet Creek
South Benfleet Creek (G.R. TQ 79 85) is a small tidal inlet
on the north bank of the River Thames about 7 miles from its
mouth at Shoeburyness. The Creek is just over 3 miles long,
from Canvey Point to South Benfleet Bridge, nearly half a mile
wide at its mouth and about 80 yards wide near the bridge.
It runs in a S.S.E.-N.N.W, direction between the low-lying land
of Canvey Island and Hadleigh Marsh. Because the surrounding
land is all below H.W.M.M.T.* level, strong concrete embank-
ments have been built along the whole length of the creek, on
both banks. It, is therefore closely confined to its channel, with
no small tributaries of fresh water entering it. There is a flow of
salt water in the main channel, even at low water.
As can be seen from figure 2, the creek is bordered on either
side by extensive saltings. These are finely dissected by narrow,
deep, muddy channels, filled at high water. The main channel is
deeply incised at low water in its lower reaches where it is too
deep and wide to ford. Just above the island, however, the
*The material for this paper was prepared while the author was a
student at the University College of North Staffordshire. He
is now a research student in Marine Zoology at the University
of Wales, University College, Swansea.
*High Water Mark of Medium Tides.