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September 2003
Are Double-Crested Cormorants Affecting Fish Populations?
The
double-crested cormorant, a goose-sized, web-footed water bird, has been creating
conflicts regarding the use of various biological and socioeconomic resources.
Populations of this species are found throughout North America, and have been
increasing rapidly. In the Narragansett Bay system of Rhode Island and Massachusetts,
the cormorant population exponentially increased from a negligible breeding population
in 1980 to an apparent carrying capacity in the late 1990s. During the time the
population of cormorants increased, the abundance of fish, such as winter flounder,
declined. Because overfishing is a major factor causing decline in fish abundance,
pressure was put on commercial and recreational fishing interests to decrease
the rate of fishing. The success of this strategy is unclear as, unfortunately,
abundance of many fish species continues to decline. Could cormorant fish consumption
be partially to blame for these declines?
To answer this question, ASA modeled the annual fish consumption by cormorants, based on the amount and size range of fish consumed per bird, foraging areas, and the number of birds feeding in each portion of Narragansett Bay. Cormorants are opportunist predators of all types of fish, but target small, slower-moving animals such as juvenile winter flounder. The losses from cormorant fish consumption were compared to trends in fish populations and, specifically for winter flounder, fishing mortality from commercial and recreational fishing.
The analysis showed that during the 1980s, fishing mortality was high and cormorant fish consumption was low. In the 1990s, fishing mortality had decreased, but the average rate of juvenile winter flounder consumption by cormorants increased. Our analysis suggests that cormorant fish consumption contributes to the continual decline in winter flounder populations.
The model results from this study support previous analyses, which suggest that juvenile survival could be the limiting factor in the Narragansett Bay population size of winter flounder. The impact of cormorant consumption on other prey species in Narragansett Bay may be significant as well, and should be considered in evaluating the impacts of fishing rates on fish populations. For more information on these results, please contact Deborah French McCay.
Photo courtesy of Don Chalfant
ASA
has continued to improve SARMAP, ASA's search & rescue tool, to include real-time
data links through COASTMAP and new lagrangian based search area solutions.
In
Australia, Sasha Zigic from Asia Pacific ASA and Nathan Benfer, a fourth-year
coastal engineering student at Griffith University, used SARMAP to evaluate its
accuracy in finding obejcts lost at sea in Gold Coast waters, Queensland. The
validation took place off the popular Gold Coast fishing spot Mermaid Reef where
the mannequin was used to simulate a fisherman lost at sea. The movements of the
mannequin were tracked using satellite positioning, covering 233m every 30 minutes.
The floating object drifted in an S-bend path displaying the complexity of wind-driven
flows and the changes in tidal currents. SARMAP proved to be successful in simulating
the movement of the mannequin.
Asia-Pacific ASA Assisting AMSA As Part Of The National Plan To Combat Oil Spilled At Sea
The
Australian Maritime Safety Authority (AMSA) co-ordinates Australia's international
responsibilities in the area of marine environment protection and oil spill response
for 18,000,000 square miles of ocean (approx 1/9th of the globe's surface area).
Since October 1999, AMSA have been using ASA's oil spill model, OILMAP, to combat
and predict the movement of oil spilled at sea. During this time the Asia-Pacific
ASA have assisted AMSA staff with technical support in respect to software related
issues and/or methodology issues, as part of their daily operations.
As of the 1 July 2003 the Asia-Pacific ASA have been assisting AMSA to expand and improve on the bathymetry and tidal database for a number of Australia's known high-risk area's, including the Great Barrier Reef Marine Park and Sydney Harbour. Also as part of the improvement process, HYDROMAP (ASA's ocean/coastal hydrodynamic model) had recently been tested and validated for a oil spill ground validation exercise undertaken by AMSA, in Moreton Bay, Brisbane during 17-18 June 2003. For more information please contact Sasha Zigic at szigic@appsci.com.
Photo courtesy of Trevor Gilbert from AMSA
ASA
is modeling the movement of oil over land and in stream and river networks in
support of pipeline companies that need to meet federal hazardous pipeline safety
regulations. As of September 2004 owners and operators of pipeline systems are
required to assess and evaluate potential effects to High Consequence Areas from
segments that leak or fail for 50% of their total pipeline miles (DOT OPS 49 CFR
195.452).
OILMAPLAND,
ASA's new addition to their extensive suite of models, is being used to assist
in meeting these regulations. The model is built as an ArcView8® extension
and links to existing pipeline network and sensitivity data. Results show the
oil footprint over land from multiple potential release sites along a pipeline.
Oil that reaches a river or stream is modeled to follow the stream network. Both
the land and water feature areas impacted by a spill can then be spatially overlaid
onto data depicting sensitive areas for impact analysis.
The OILMAPLAND model
has successfully been used to meet the DOT regulation requirements for a number
of pipeline companies.
The land spill model builds on ASA's expertise in oil spill modeling and expands the modeling services we are able to offer our clients into the land environment. For more information on land spill modeling please contact Chris Galagan.
On 16-19 September, Roddy Thomas will be attending the COPEDEC Conference in Colombo, Sri Lanka. This is an environmental conference that includes a strong focus on a wide range of modeling applications in the Middle East, India and SE Asia.
Roddy
Thomas and Eduardo Yassuda will be attending the Argentina Oil &
Gas Expo in Buenos Aires on 6-10 October. All the information and latest technology
for the energy industry will be displayed and discussed at the expo.
ASA South America in one of the sponsors of the "National Oceanographic Week"
that takes place the 27-30 October in São Paulo. During this week the National
Oceanographic Association holds their bi-annual meeting. At this meeting, Eduardo
Yassuda will be presenting Applications of Oceanography in Environmental Studies
in South America, and Jose Edson will teach a course in numerical modeling.
Christopher
Galagan, Sankaranarayanan Subbaya, Malcolm Spaulding, Craig
Swanson, Matthew Ward and Eduardo Yassuda are scheduled to
present papers at ECM8, the 8th International Conference on Estuarine and Coastal
Modeling to be held in Monterey, CA on 3-5 November. Additional ASA coauthors
include Deborah French McCay, Tatsu Isaji and Paul Hall.
ASA papers will cover such topics as sediment transport modeling, oil spill modeling,
hydrodynamic modeling, integrated monitoring and forecasting systems and flushing
models.
WQMAP Version 5.0
The new WQMAP Version 5.0 is now available, which includes updated gridding, open boundary database, bathmetry database, and easier to use tools. A demo and student version is available at www.wqmap.com.
On
the 7th of May, Sasha Zigic participated in the National Marine Chemical
Workshop in Melbourne Australia. During the workshop, Sasha provided the chemical
trajectory & fate modeling support during the recent training program exercise.
It was very well received and many of the key stakeholders (fire authorities,
environmental & maritime agencies) in attendance were impressed by the capabilities
of the system.
Deborah French McCay and Craig Swanson presented
papers at the Mount Hope Bay Symposium on 10 May, which was part of the NEERS/SNECAFS
Joint Meeting at the University of Massachusetts Dartmouth. Deborah, as lead author
with Jill Rowe who also attended, presented: Estimated Impacts of Cormorants
on Fish Populations in the Narragansett Bay Estuary. Craig, as lead author with
Hyun-Sook Kim who attended as well, summarized the extensive hydrothermal
modeling ASA has conducted over the last six years in Simulated Thermal Variations
in Mount Hope Bay and Application to Assessing Ecosystem Effects.
Claudia
Santos Suárez and Eric Anderson delivered and provided training
for SIMAP to PEMEX on marine modeling in support to exploration and production
activities in the Bahía de Campeche. The workshop was held at the GDS office
in Ciudad del Carmen, Campeche on 15-16 May 2003, where participants representatives
from PEMEX, specialized in various environmental and biological fields learned
about the use of ASA's latest version of SIMAP, as well as new tools for oil spill
modeling and impact assessment.
On
10-12 June Deborah French McCay attended the 26th annual Arctic and Marine
Oilspill Program(AMOP) Technical Seminar in Victoria, BC. Debbie presented the
results of an oil spill modeling study to assess the potential consequences of
hypothetical oil spills from the National Defense Reserve Fleet located in the
James River, Virginia, entitled Assessment of the Potential Impacts of Oil Spills
in the James River, Virginia coauthored with Nicole Whittier, Tatsu
Isaji, and William Saunders). The paper is available in the AMOP proceedings,
from our website, or by contacting us.
ASA, in conjunction with the Naval
Undersea Warfare Center and SubChem Systems, participated in a mine warfare exercise
to detect TNT from submerged mines. ASA's COASTMAP was used to visualize the AUV
data in 3D. The successful exercise was conducted at Duck, NC in the beginning
of June.
Roddy
Thomas attended the MARE-DASM Conference in Ghent, Belgium on 12-13 June.
The conference's focus was on marine resource damage assessment, liability and
compensation. A series of papers and workshops considered the growing debate in
Europe on a suitable methodology for assessing damages in the event of the release
of oil or hazardous substance into the marine environment. The conference coincided
with the promulgation of a new EEC Environmental Directive: Standing and Assessment
of Damages, which is being submitted to Parliament for approval this summer.
Sankaranarayanan Subbaya attended the 2003 Gordon Research Conference
on Coastal Ocean Modeling held at Colby Sawyer College, New London, NH during
22-27 June. Some recent advances in operational coastal ocean modeling, data assimilation,
physical-biological coupling and Lagrangian descriptions were presented by experts
in the field.
NOAA
and State of Louisiana personnel attended a training/workshop at ASA 7-9 July,
given by Deborah French McCay, Jill Rowe and Nicole Whittier.
The training and discussion included: technical description of the "Type
A" natural resource damage assessment model developed by ASA and included
in US (CERCLA) regulations; updates to the model system now included in SIMAP
(oil spill analysis) and CHEMMAP (chemical spill analysis); and potential applications
to injury quantification and compensatory restoration scaling.
Craig
Swanson presented COASTMAP,
a Nowcast/Forecast System at the Coastal Zone 03 conference held in Baltimore
13-17 July. The presentation, coauthored with Matthew Ward, Eoin Howlett
and Malcolm Spaulding, described the major features of COASTMAP and how
the software can be an effective tool to provide environmental monitoring and
modeling information to a variety of users in coastal areas.
Chris
Galagan and Matthew Ward attended the Northeast Maritime Security Conference
& Workshop on 23-24 July, held at the UCONN Avery Point campus. The conference
discussed maritime threats and the ability to use technology in responding to
such threats to reduce security risks.
Eduardo Yassuda provided
technical training for Petrobras about "Computational Modeling Applied to
Environmental Impact Studies" in August at the research center (CENPES) in
Rio de Janeiro.
Matt
Ward delivered and provided training for WQMAP v5.0 to the Naval Oceanographic
Office (NAVO) at the Stennis Space Center in Mississippi on 11-15 August. NAVO
is also using COASTMAP to develop the initial conditions and environmental forcing
for WQMAP.
Deborah
French McCay and Eduardo Yassuda visited Petrobras' research center
(CENPES) in Rio de Janeiro the week of 18 August, where they discussed the use
of SIMAP by Petrobras. Deb presented two seminars on 19-20 August to Petrobras
scientists and engineers, summarizing the technical capabilities of SIMAP, its
use in spill assessments such as for the January 2000 spill in Guanabara Bay,
ecological risk assessment applications, and usefulness for training and education.
Petrobras has been using SIMAP for two years, developing data for assessing the
January 2000 spill, and evaluating SIMAP's potential role in their research program.
Eoin
Howlett presented Developing Technologies - Crisis Management System Overview
at the September Rhode Island Port Safety & Security Committee Meeting.
The presentation focused on the use of ASA's Crisis Management System as a tool
for security exercises.
In the beginning of September, Jose Edson
delivered the hydrodynamic, OILMAP, and MUDMAP simulations to BMA/Petrobras. The
model includes local and remote forcing in a highly baroclinic system, coupling
continental shelf and deep ocean dynamics in one of the most environmentally sensitive
areas in the northeast coast of Brazil.
Modelling Of Moreton Bay Using
An Ocean/Coastal Circulation Model, authored by Sasha Zigic, Marc Zapata,
Tatsu Isaji and Brian King was published in the Coasts and Ports
conference proceedings. The conference was held in Auckland, New Zealand on 9-12
September.
Alvin Goh from Control IT in Singapore presented a paper on behalf of Eoin Howlett at the 2nd International Conference On Port & Maritime R&D And Technology in Singapore. The paper was titled Real-Time Marine Emergency Response Tools.
Craig Swanson attended theEstuarine Research Federation conference, Estuaries on the Edge, in Seattle on 14-18 September. He presented COASTMAP: A Globally Relocatable Nowcast / Forecast System. Coauthors included Matthew Ward and Malcolm Spaulding.
New Faces
Maria Regina Fonseca Guimaraes has joined the ASA South America team. Maria has a MS and PhD in Physical Oceanography from the Oceanographic Institute of the University of Sao Paulo, where she was working as a post-doc with GCM - Global Circulation Models - Isopicnal.