UGA Shellfish Laboratory
Home | Announcements | Fisheries | Aquaculture | Invasive Species | Histology & Histopathology | Publications | Adopt A Wetland| | Oyster Restoration | Education | Links|
Invasive Programs
1. Port Monitoring
2. Green Mussel:
Green Mussel
Fact Sheet
Green Mussels
in Georgia
3. Report unusual occurrences of aquatic organisms to Marcy Mitchell (912) 598 2348 marcyann@uga.edu
4. Help Stop Aquatic Invasive Species
1. BASELINE PORT SURVEYS FOR INTRODUCED MARINE MOLLUSCAN, CRUSTACEAN & POLYCHAETE SPECIES IN THE SOUTH ATLANTIC BIGHT
Alan Power1, Randal Walker1, Martin Posey2, Troy Alphin2, Marcy Ann Mitchell1, & Carolyn Belcher3
1University of Georgia Marine Extension Service, Shellfish Research Laboratory,
20 Ocean Science Circle, Savannah GA 31411-1011
2University of North Carolina at Wilmington, Department of Biological Sciences,
Center for Marine Science, 5600 Marvin Moss Lane, Wilmington NC 28409
3University of Georgia Marine Extension Service, Commercial Fisheries Section,
715 Bay Street, Brunswick GA 31250-8687
Funded by Sea Grant's Aquatic Nuisance Species Program
ABSTRACT
The ports of the South Atlantic Bight are currently undergoing phenomenal growth.
Baseline biological surveys are critical if we are to reduce the risk of invasive
species being introduced and transferred to and from this region. A comprehensive
search for molluscan, polychaete, and crustacean species in the major ports
of the South Atlantic Bight was undertaken during the summer 2003 to provide
baseline information on native biodiversity, and on the presence, distribution
and relative abundance of non-indigenous species in the region. An array of
field sampling devices, including crab traps, minnow traps, crab scrape, piling
scrapings, fouling plates, and benthic cores were used to conduct the surveys.
Project results will contribute to national baseline information required to
evaluate general patterns and regional differences in invasion rates. Information
will be shared with the Smithsonian’s National Ballast Water Information
Clearinghouse, the Aquatic Nuisance Species Task Force, and the USGS Non-indigenous
Aquatic Species Program, coastal natural resource managers, and the respective
port authorities. Sea Grant’s Aquatic Nuisance Species Program provided
funding for this research.
INTRODUCTION
Marine species are dispersed throughout the world by ocean currents, however
a spatial pattern of biodiversity exists due to natural barriers (e.g. temperature,
salinity, predation, competition, land masses). In recent years, the transportation
of planktonic organisms in ballast water has allowed many species to successfully
penetrate these barriers (e.g. zebra mussel, Dreissena polymorpha; asian clam,
Corbicula fluminea; green mussel, Perna viridis). Ballast is carried by ships
to ensure stability, trim and structural integrity. It has been estimated that
at least 7000 different species are being carried in ballast tanks around the
world and that roughly twenty one billion gallons of foreign ballast water are
discharged in US waters annually (Global Ballast Water Management Programme).
Introduced species result in a combination of economic, environmental and health
concerns.
While commercial ports represent the main entry point for many introductions,
only a few US ports have been investigated in terms of the characterization
of non-indigenous flora and fauna present (Englund, 2002; Hines & Ruiz,
2000; Cohen & Carlton, 1995). One region for which information is particularly
lacking is the South Atlantic Bight, which stretches from Cape Hatteras, North
Carolina to West Palm Beach, Florida. This region has been heavily impacted
by anthropogenic activities and currently has many of the largest container
and automotive ports in the nation. These ports are undergoing phenomenal growth
with trade areas worldwide and therefore represent an increasing threat for
invasions by non-indigenous species.
The University of Georgia in collaboration with the University of North Carolina,
Wilmington conducted baseline port surveys in the South Atlantic Bight (Savannah
GA, Charleston SC, Jacksonville FL, and Wilmington NC) in summer 2003. The project
goal is to determine whether non-indigenous species have been, or are becoming
established in the region. We decided to focus our efforts on the ecologically
important mollusk, crustacean and polychaete components of the biota. Our objectives
are to:
· Conduct an extensive literature review of any existing biotic surveys
for the region.
· Describe each port in terms of their history, geology, hydrography,
and shipping movements.
· Conduct a comprehensive search for mollusk, crustacean and polychaete
species in various community types at each port, above each port and in the
outer reaches of each port.
· Provide baseline information on native biodiversity, and on the presence,
distribution, relative abundance and trophic status of invasives.
· Identify priority invasive species.
· Determine community structure, sediment size and water quality across
this geographical region.
· Integrate data with GIS.
· Disseminate results to contribute to national knowledge base of invasive
species.
METHODOLOGY
Since invasive species are typically patchily distributed, we used an array
of sampling devices across different habitats, similar to that described for
an Australian nationwide port survey (Hewitt & Martin, 2001). A power analysis
to determine the appropriate sampling effort using the methods of Green &
Young (1993) for rare species with a poisson distribution suggested that a sample
size of approximately 13 samples is necessary to detect a species with a mean
Poisson density of 0.1 individuals per sample unit at a 95% probability (Hewitt
& Martin, 2001).
Trapping: Thirteen locations within each port and 13 each in the outer and upper
reaches of each estuary were sampled with baited traps. Standard commercial
crab traps were used to capture mobile large crabs. In addition, galvanized
minnow traps were used to capture smaller crustaceans.
Fouling Organisms: A 1m2 area was scraped from each of thirteen pier/bridge
pilings within each port during low tide. Additionally, 13 Hester-Dendy colonizing
plates were suspended in the water column for a one-month period.
Epibenthos: A try-net (20ft stretched length, 54 ft perimeter) with 1-inch stretched
mesh webbing was towed for 5 minutes at 13 sites within, above and below each
port.
Benthic Infauna: Triplicate core samples (10 cm diameter, 15 cm depth) were
taken at 13 locations within, above and below each port. Each sample was rinsed
on a 1 mm mesh sieve to concentrate our efforts on the juvenile and early life
stages of decapods, amphipods, other crustaceans, non-juvenile bivalves and
larger polychaete taxa.
Sediment Analysis: An additional core sample was also taken at each of the benthic
infaunal core sampling sites and a sub sample was later frozen to determine
the organic content and to characterize the particle sizes.
All biological samples were preserved in 10% seawater buffered formalin and
later transferred to 70% ethanol. Additionally, the fouling organisms samples
were first placed into a narcotizing magnesium chloride solution for one hour
prior to preservation. Samples are currently being sorted and identified to
species level.
ANTICIPATED OUTCOMES
Economically, marine invasives can be very expensive to control, proliferating
rapidly and fouling up waterways, industrial intake-pipes, and boats and fishing
gear. Environmental costs are also often devastating, with changes in the structure
and functioning of ecosystems. Our natural resources and biodiversity can be
threatened in terms of increased competition for food and space, predation,
pathogens, and parasites. We have recently confirmed the presence of the green
mussel (Perna viridis) throughout the coastal waters of Georgia. Given the economic
and environmental problems experienced in the Tampa Bay region on the Gulf Coast
of Florida since being introduced here a few years ago, the coastal community
in Georgia is indeed concerned. It is imperative that we identify ALL invasive
species currently inhabiting our waters and also that we continue to closely
monitor for further introductions. Our data will provide the baseline against
which future introductions can be measured. The survey could serve as a regional
early warning system, facilitating the early detection of new invasions within
the window of opportunity where eradication efforts may be successful. An assessment
of the distribution and abundance of invasives throughout this geographical
range may also indicate their ecological and environmental tolerances with the
potential for prediction of the eventual geographic and ecological impacts.
The survey data will also provide baseline information for native biodiversity
that is lacking for the region. The benefits of the proposed research project
will be widespread, filling the void of information that exists for this important
area that spans four states (North Carolina, South Carolina, Georgia, and Florida).
Survey results will be shared with the Smithsonian Environmental Research Center’s
National Ballast Water Information Clearinghouse (http://invasions.si.edu/ballast.htm)
that was developed for the synthesis, analysis, and interpretation of national
data concerning ballast water management and ballast-mediated invasions. Survey
results will also be provided to the Aquatic Nuisance Species Task Force (http://www.anstaskforce.gov),
and the USGS Non-indigenous Aquatic Species Program (http://nas.er.usgs.gov)
to enhance the national knowledge base of invasives.
ACKNOWLEDGEMENTS
Funding was provided by NOAA’s National Sea Grant Aquatic Nuisance Species
Program, the University of Georgia Marine Extension Service and the University
of North Carolina at Wilmington. We would like to thank Ms. Dodie Thompson,
Ms. Ellie Covington, Ms. Mary Sweeney Reeves, Mr. Clay Holloway, Mr. Lindsay
Parker, Mr. Marty Higgins, Mr. Paul Daniels, Mr. Paul Christian and Mr. Thomas
Shierling for assisting in the collection of samples. Countless others have
helped in the planning and implementation of these surveys; in particular we
acknowledge the efforts of the Georgia and North Carolina Ports Authorities,
the Coast Guard, the Georgia, South Carolina, North Carolina, and Florida Department
of Natural Resources, the Army Corps of Engineers, the Marine Patrol, the Southeastern
Regional Taxonomic Center, Sapelo Island National Estuarine Research Reserve,
and the Nature Conservancy.
REFERENCES
Cohen, A.N. and J.T. Carlton. 1995. Nonindigenous aquatic species in a United
States estuary: a case study of the biological invasion of San Francisco Bay
and delta. Report to U.S. Fish & Wildlife Service, Washington, DC and National
Sea Grant College Program, Connecticut Sea Grant. 246 pp.
Englund, R.A. 2002. The loss of biodiversity and continuing nonindigenous species
introductions in freshwater, estuarine, and wetland communities of Pearl Harbor,
Oahu, Hawaiian Islands. Estuaries 25(3):418-430.
Green, R. H. and R.C. Young. 1993. Sampling to detect rare species. Ecological
Applications 3(2):351-356.
Hewitt, C.L. and R.B. Martin. 2001. Revised protocols for baseline port surveys
for introduced marine species: survey design, sampling protocols and specimen
handling. Centre for Research on Introduced Marine Pests. Technical Report No.
22. CSIRO Marine Research, Hobart. 46 pp.
Hines, A.H., and G.M. Ruiz (eds.). 2000. Biological invasions of cold-water
coastal ecosystems: Ballast-mediated introductions in Port Valdez / Prince William
Sound, Alaska. Final Report to Regional Citizens' Advisory Council of Prince
William Sound, 313 pp.
2. GREEN MUSSEL