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Fish Habitat Ecology
Estuaries are receiving increasing pressure as people continue
to utilize the coastal zone for housing, recreation, and industrial
purposes. Concomitant with the increased utilization often
comes decreases in water quality and loss or degradation of
habitat. This is particularly important for those species
that are dependent on estuaries as nurseries or for feeding
and reproduction. McHugh (1966) estimated that approximately
two thirds of the commercially important species in the U.S.A.
are estuarine dependent. Some would argue that many estuarine
species are not truly dependent on estuaries (Lenanton and
Potter 1987) and could survive in the coastal zone. Yet another
view is that the estuary and the nearshore coastal zone are
a continuum (e.g. Milstein 1981). McHugh's estimate is often
repeated but seldom reevaluated although the extent, nature,
and focus of our commercial fisheries has changed from that
time. Prompted by our concern for the continued viability
of New Jersey's recreational and commercial fisheries and
our interests in the ecology and life history of estuarine
fishes and their habitats we have begun to coordinate our
research activities to focus on the habitat ecology of estuarine
dependent fishes of economic and ecological importance in
New Jersey. We recognize, of course, that many of these same
species are of similar importance throughout the Middle Atlantic
Bight. We intend to place special emphasis on the juvenile
stage, rather than the planktonic larval stages, because constructive
management of juvenile nursery habitats (protection, restoration)
is possible and the emerging consensus is that survival during
the early juvenile stage has important implications for year
class strength and subsequent abundance of the adult population.
In response to these needs we are attempting to answer the
following questions. What are the temporal and spatial patterns
of fish utilization, growth and survival in estuarine habitats?
What is the impact of predator/prey relationships on habitat
utilization? What are the functional relationships and interactions
between and among the dominant habitat/species in estuaries?
As a result of the above, are some habitats critical nursery
areas for some species? How can these habitats be protected
or enhanced?
We expect, as our experience with other estuarine species
grows, our composite understanding of estuarine-continental
shelf coupling, energy transport, and recruitment patterns
will expand logarithmically.
McHugh, J.L. 1966. Management of estuarine fishes. Am. Fish.
Soc. Spec. Publ. 3:133-154.
Lenanton, R.C.J., and I.C. Potter. 1987. Contributions of
estuaries to commercial fisheries in temperate western Australia
and the concept of estuarine dependence. Estuaries 10(1):28-35.
Milstein, C.B. 198. Abundance and distribution of juvenile
Alosa species off southern New
Jersey. Trans. Am. Fish. Soc. 110:306-309.
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