| Evaluation
of Marsh Restoration in Delaware Bay
 The
objectives of this ongoing program, which beganin 1996, are
to determine the patterns and processes of fish utilization
for restored marshes in Delaware Bay. The basic approach is
a comparison of fish species composition, life history stage,
size and growth across the major habitat types (small marsh
creeks, large marsh creeks) in mesohaline and oligohaline
restored and reference marshes during the period of greatest
fish availability (May through November). The target species
for this project include weakfish (Cynoscion
regalis), white perch (Morone
americana), spot (Leiostomus
xanthurus) and bay  anchovy
(Anchoa mitchilli), although
all fish species and blue crabs (Callinectes
sapidus) have been routinely included in all sampling
and analysis. This approach will provide continued and consistent
monitoring of marshes that were restored beginning in 1996.
A separate program providing another discrete evaluation
of the success of the restoration in Delaware Bay of marsh
dominated by Phragmites by comparing
the role of predators in a treated marsh (Phragmites
exposed to herbicides and burning) and in adjacent reference
(Phragmites dominated but not
treated and Spartina alterniflora)
marshes in Alloway Creek. We have conducted preliminary investigations
of 1) the seasonal occurrence, relative abundance, and species
composition of large piscivorous predators, 2) the food habits
and thus the trophic linkages for white perch (M.
americana) based on ongoing monthly sampling and directed
sampling, and 3) movements of this species.
The approach is similar to our focused studies on striped
bass (Morone saxatilis) in 1998
in lower Delaware Bay marshes in which we successfully determined
the pattern of habitat use and diet of this economically and
ecologically important predator (Tupper and Able 2000). In
year one of this study white perch (M.
americana) was found to be the dominant predator in
Alloway Creek (80.2% of the piscivores caught in year one)
and for those individuals that had fish in their stomachs,
78.8% of their fish diet by weight was mummichog (Fundulus
heteroclitus); thus, white perch is an important focal
species for studying trophic linkages in restored versus reference
marsh creeks.
In a continuing attempt to evaluate the impact of Phragmites
on marsh surface fishes we are determining the movement patterns
of early-stage, young-of-the-year (YOY) fishes that originate
in Spartina-dominated marshes
to determine if dispersal from this vegetation type is the
source of the fish that subsequently use Phragmites-dominated
marshes at larger sizes. This evaluation is based on tag/recapture
experiments for small (<25 mm TL) YOY fishes, particularly
the ecologically important mummichog (F.
heteroclitus).
We intend to use a tag/recapture technique to determine movements
and residence time for larval and small juvenile Fundulus.
Coded wire tagging, an approach we have previously used in
Delaware Bay marshes on larger Fundulus
(Teo and Able in press) is being used to individually tag
small fish (as small as 15 mm TL) during the summer. This
approach is allowing us to understand the movements and habitat
use of individual fish and more importantly will provide and
improved comparison of fish movements in Phragmites
vs. Spartina marshes.
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