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| Current fisheries research and future ecosystems science in the Northeast Center: collected
abstracts of the Northeast Fisheries Science Center’s Eighth Science Symposium, Atlantic City, New Jersey,
February 3-5, 2004. Northeast Fish. Sci. Cent. Ref. Doc. 04-01
SESSION I |
| A history of ecosystem studies of the U.S. northeast shelf ecosystem,
1807 – 2004 |
Session I, Abstract I-1
ORAL PRESENTATION |
Sara P. Adams and Kenneth
Sherman
NOAA/NMFS/NEFSC, 28 Tarzwell Drive, Narragansett, RI 02882-1152 |
In 1807, President
Jefferson sent a request to the American Philosophical Society for proposals
for a Coast Survey that was to serve as the agency that would later
be joined to the National Marine Fisheries Service in 1970 to form
the foundations of today’s NOAA. Now in 2004, the principal NOAA mission
goal is to protect, restore, and manage the use of coastal and ocean
resources through ecosystem based management. We trace the evolution
of scientific exploration and the genesis of the marine ecosystem based
approach in the United States from the early days of the Coast Survey
through the joint studies of Ferdinand Hassler, Alexander Dallas Bache,
Louis and Alexander Agassiz, Spencer Baird and Henry Bigelow through
the succession of directors of the NMFS Woods Hole Laboratory from
1846 to the present day demonstrating that NOAA’s principal goal of
today is attributable to studies of the US Northeast Shelf.
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| Potential contribution
of new technologies to essential fish habitat designation |
Session I, Abstract I-2
ORAL PRESENTATION |
Jeffrey Pessutti and John
Manderson
NOAA/NMFS/NEFSC, 74 Magruder Road, Highlands, NJ 07732 |
It is generally
accepted that habitat conservation is necessary for the protection
of ecologically important species and sustainable fisheries. However,
the habitat requirements of many species, particularly those using
the continental shelves are still largely unknown. Advancements in
marine remote sensing, specifically the development of sensors deployed
on satellites, ships, autonomous underwater vehicles, and on the bottom,
offer the potential to monitor variation in pelagic and benthic habitat
characteristics and animals’ movements. The extents and resolutions
provided by these technologies may permit the development of robust
and spatially and temporally explicit functional habitat models. Remotely
sensed data combined with underwater video, acoustic fish tracking,
and traditional sampling approaches will allow for the development
of distribution-based models of habitat use for shelf species. Such
models could provide the framework to implement the same technologies
for the study of fine-scale patterns of habitat use and habitat effects
on growth, survival, reproduction and dispersal. The combination of
fine-scale habitat suitability and use studies with distribution based
models of habitat will help to identify not only where essential habitats
are found, but at what life history stages specific habitats become
important. In this presentation we review environmental data available
or soon to be available for the New York Bight and present sampling
approaches and a conceptual framework for a shelf habitat research
program.
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| Bay scallop, Argopecten irradians irradians, restoration
efforts in the northeastern United States |
Session I, Abstract I-3
ORAL
PRESENTATION |
Ronald Goldberg
NOAA/NMFS/NEFSC, 212 Rogers
Ave., Milford, CT 06460-6499 |
| Over the last several decades, there has been a marked decline in
population abundance of bay scallops, Argopecten irradians irradians (Lamarck,
1819), in nearshore waters and estuaries of the northeastern United
States. Losses of habitats, deterioration of water quality, and harmful
algal blooms have probably contributed to this decreased abundance. Bay
scallops generally spawn only once in their short 18-22 month lifespan
and this characteristic increases the possibility of recruitment limitation
when year-class survival is poor. In northeastern coastal states, local
shellfish commissions, community groups, and shellfishers have explored
many ways to restore or enhance the bay scallop resource. Establishment
of spawner sanctuaries, direct transplantation of hatchery seed, and
collection of native spat have all been attempted, but results have
been highly variable. In most cases, no genetic analysis relating
parent stock to progeny is available. Additionally, unpredictable
and relatively abrupt changes in habitat (eelgrass decline), environmental
quality (harmful microalgal blooms), or low levels of natural spatfall
available for collection can negate enhancement efforts. Unfortunately,
many projects have been curtailed after one or two seasons, when sustained
and adaptive efforts are required. Some of the bay scallop stock enhancement
projects in this region have, however, documented increased production
or have resulted in improved methodology. Specific projects in Massachusetts,
Rhode Island, Connecticut, and New York are reviewed in an attempt
to determine promising strategies to pursue in the future. Keywords: bay scallops, Argopecten, stock
enhancement
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| Condition of young-of-the-year bluefish (Pomatomus saltatrix)
from two different estuaries along the Mid-Atlantic Bight |
Session I, Abstract I-4
ORAL PRESENTATION |
Jennifer C. Samson and Ashok
D. Deshpande
NOAA/NMFS/NEFSC, 74 Magruder
Road, Highlands, NJ 07732 |
Estuaries
along the Mid-Atlantic Bight (MAB) have been identified by the National
Marine Fisheries Service as essential fish
habitat for young-of-the-year (YOY) bluefish, Pomatomus saltatrix. Several
MAB estuaries are contaminated with PCBs, PAHs, and heavy metals. YOY
bluefish utilizing polluted MAB estuaries during periods of rapid growth
and development are conceivably chronically exposed to contaminants
in the water column, sediments and food. The objective of the study
was to compare the condition of YOY bluefish from two different MAB
estuaries (Great Bay, New Jersey-pristine and Hackensack River, New
Jersey-contaminated) using biomarkers that target different levels
of biological organization. Fish were collected upon immigration into
estuaries in summer and just prior to emigration in fall. Summer collections
were analyzed for baseline PCB contamination in whole fish. From the
fall collection, fish have been analyzed for gross pathologies, class
and concentration of lipids in tissues, and DNA adducts. Analyses
in progress include concentration of PCBs in tissues and vitellogenin
and cytochrome P-450 induction in the liver. Analysis of biliary FACs
is planned. Significant differences were detected between bluefish
from the two different estuaries including higher total lipid content
and an increase in hepatic DNA adducts in fish from the contaminated
estuary. Analyses of field-collected fish from two different estuaries
are expected to provide much needed information on the impact of habitat
quality on the condition of YOY bluefish condition. Understanding the
impact of habitat qualities on fish health is an important aspect of
essential fish habitat designation, management and protection.
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| The distribution, diet,
and growth of young-of-the-year bluefish, in a northwest Atlantic estuary |
Session I, Abstract I-5
ORAL PRESENTATION |
John G. Hilbert
Jr., Beth Phelan, John E. Rosendale, and Carol Meise
NOAA/NMFS/NEFSC, 74 Magruder Road, Highlands, NJ 07732 |
| We
used multi-panel gill nets and 100-foot haul seines to study the
distribution, diet, and growth of young-of-the-year bluefish. Bluefish
were collected from June to October 2003 in the Navesink River/ Sandy
Hook Bay estuary. Gill nets were fished biweekly for 2h at stratified
random sites at depths less than 3m. Haul seines were fished biweekly
at 6 fixed stations. A total of 2966 fish was captured, (seine: N=1986,
30-248 mm FL, mean FL=108 mm); (gill net: N=980, 72-385 mm FL, mean FL=164
mm). Bluefish were first collected in June and reached peak abundance
in July (bay=1745, river=185). Overall, more fish were caught in the
bay than the river. Length frequencies derived from catch data were
used to estimate daily growth rates. Preliminary analysis showed that
bluefish grew at an average of 1.34mm/day. A total of 372 individuals
was analyzed for stomach contents. Four indices: percent weight (%W),
percent number (%N), percent occurrence (%O), and percent index of relative
importance (%IRI) were calculated for all prey items consumed. Mysids
were the most important prey (%W=37, %IRI=91) followed by silversides Menidia
menidia (%W=22, %IRI=3) and sand shrimp Crangon septemspinosa (%W=9,
%IRI=4). The presence of a large amount of invertebrate prey may suggest
that they are more important diet items than previously expected.
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| True confessions: lessons
learned and new research initiatives
in the microalgal mass culture room at Milford |
Session I, Abstract I-6
ORAL PRESENTATION |
Mark S. Dixon and Gary H.
Wikfors
NOAA/NMFS/NEFSC, 212 Rogers Ave., Milford, CT 06460-6490 |
| The
Milford Mass Culture Room (MCR), houses a unique system for the cultivation
of research-grade microalgae. The research of Dr. Ravenna
Ukeles, of the Milford Laboratory, on techniques for the mass culture
of microalgae led to the design and construction of the MCR that was
completed in 1970. A 1973 publication describes the carboy system
that, with only minor modifications, is in current use. This system
allows for production of large quantities of contaminant-free algal
biomass. Semi-continuous culture management under consistent conditions
of light, temperature, and media composition provides a product of
repeatable and reliable quality. Large (500-l) open tanks, also in
the MCR, serve as models for commercial aquaculture applications and
provide large volumes of algae to other Milford research initiatives. Despite
a long history, the MCR is not static. Recent challenges,
new research directions and applications, and technological developments
have taught us not to rest on past success. For example, research
on bivalve and rotifer nutrition led to the replacement of some algal
strains traditionally used in aquaculture with others (e.g., high-lipid Tetraslemis,
and Pavlova). In the past, open cultures mixed with bubbled
air were very susceptible to bacterial degradation and limited to short-term
(5-7 days) batch harvesting. Replacing bubbling with mechanical mixing
(initially a wooden paddle and currently a mechanized foil) significantly
increased production and permitted long-term (2-3 years), semi-continuous
production. We also found that open cultures with higher air-surface
area-to-volume ratio were more productive and sustainable. Ciliate
contamination in open cultures became an issue in rotifer-feeding applications.
This problem was addressed first by using fresh water and artificial
salt to eliminate the seawater source – effective, but too expensive. More
recently, we are using sub-micrometer, capillary tangential-flow filtration
of seawater. The importance of supplemental carbon dioxide, as both
carbon source and pH regulator, in bacteria-free carboy cultures was
re-enforced through chance observations and subsequent adjustments. And
most recently, we discovered that the pH buffer in our carboy and tank
media degrades to ammonia (and much faster in bacterized cultures). This
ammonia stresses grazers in closed systems, and degradation of the
buffer reduces its effectiveness; the buffer problem is a top MCR priority. Current
MCR work is a combination of refining existing procedures and applying
them to new initiatives, including: studying harmful algal effects
upon native and aquacultured grazers, using flow-cytometry to evaluate
algal culture dynamics and grazer physiology, gaining a better understanding
of the chemical processes within the algal media, and developing new
and more effective methods of algal production.
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