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Deepwater Horizon Oil Spill, Fisheries, Seafood, and Wildlife
Overview
• Gulf Fisheries Concerns• Seafood Health and Safety• General Threats to Wildlife– Turtles– Mammals– Birds
Photo credit: Carolyn Shaw, LA Times
Deepwater Horizon Wellhead
Impacts to Coastal Habitats
• Vegetation coverage– Smother, stress, potential death
• Weakened marsh soils– Potential accelerated erosion from
waves and storms
• Persistence of oil and byproducts– Beaches, marshes, water column– Long-term effects?????
Photo credit: Carolyn Shaw, LA Times
Photo Credit: Dauphin Island Sea Lab
The Gulf of Mexico has more than half of the coastal wetlands in the continental U.S.
Gulf of Mexico Commercial Fisheries
• One of most productive fisheries in the world
• Dockside Value 2008 $661.4 million
• $365.5 million from shrimp
Source: NMFS 2008
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More than 3 million recreational anglers took 24 million fishing trips in the Gulf of Mexico in 2008 and contributed well over a billion dollars to the Gulf economy. Source NOAA
Fisheries Impacts?• Egg, larvae, juvenile mortality• Declines in recruitment to older class structures
– Negative impacts on rebuilding plans– Short and long-term economic impacts*
Photo credit: George Burgess, FLMNH Photo Credit: Jim Franks, Gulf Coast Research Laboratory, USM
Shrimp Life Cycle
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Image credit: Dawn Witherington, FWC
Plankton
Gulf Dead Zone Concerns
Which of the following control measure(s ) is/are used to ensure the Gulf’s Commercial
Seafood Supply is and remains safe?
A. Monitoring of harvest watersB. Precautionary closures of certain
waters and fisheriesC. Hazard Analysis Critical Control
Point (HACCP)D. Sensory and analytical monitoringE. Public advisoriesF. All the above
Photo credit: Katie Semons, NOAA
Precautionary Fisheries Closures
The area closed to all fishing now measures 31,801 sq mi (82,363 sq km) and covers about 13% of the Gulf of Mexico exclusive
economic zone.
How is seafood evaluated for contamination?
• Sensory testing– Trained professionals – Detection of “taint”
• Analytical testing– water, sediments, tissues
Photo credit: Bill Haber AP Press
Gas chromatography and mass spectrometry
Polycyclic Aromatic Hydrocarbons (PAHs)
• Product of oil degradation and incomplete combustion
• Complex and naturally occurring– Not all harmful
• Water soluble*• At high levels can
pose health risks**
Photo credit: Carolyn Carol, LA Times
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How do PAHs get into seafood?
• Uptake through Bioconcentration (filtering) or
• Biomagnification
• Grilling with contaminated coal/wood burning
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Is all seafood equally at risk to contamination?
• NO• Depends on species – (i.e. shellfish vs finfish/crustaceans)
• Exposure level & duration• Life stage• Sex• Environmental factors
(salinity/ temp)• Exposure to other
chemicals
Mollusks
Crustaceans/ Finfish
Will all exposed seafood remain contaminated?
NO!• Marine life can gradually eliminate contaminants.– Days to months depending on exposure and metabolism
Photo credit: Bryan Fluech, FSG
Dispersants: Helpful or Harmful?• Considered to have low
potential to bioaccumulate in seafood products– Not considered to pose safety
concerns*
• Factors– Exposure duration/ level– Species– Sex– Life stage– Environmental factors
• Ongoing monitoring efforts
Photo credits: NOAA
?Long-term Food Web Impacts
Wildlife Impacts3 Direct Pathways
INGESTION – when animals swallow oil particles directly or consume prey items that have been exposed to oil
ABSORPTION – when animals come into direct contact with oil
INHALATION – when animals breathe volatile chemicals released from oil or from dispersants
Photo credit: Carolyn Shaw, LA Times
Indirect Effects on Wildlife
• Relocation of home ranges to search for new sources of food–Decreased habitat use
• Increases in the amount of time animals must spend foraging– Food availability
• Disruptions to natural life cycles – Migration, nesting patterns
Image credit: Bryan Fluech, FSG
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Factors Influencing Degree of Impact
• Quantity and Duration of Exposure
• The pathway of exposure
• The age, reproductive state, and health of each animal
• The type of synthetic chemicals used by response teams to clean the spill
Image credit: UF/IFAS
Sea Turtles• 5 species in Gulf of Mexico• Adults susceptible to oil though
inhalation, ingestion• Eggs/hatchlings susceptible through
absorption• Nest Relocation Efforts
Source: Deepwater Horizon Unified Command
Photo credit: Rookery Bay NERR
Mammals21 species inhabit N Gulf of Mexico
• Skin irritation• Infection• Inhalation during
surface breathing• Ingestion– Baleen Feeding*• Bryde’s Whale
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Source: Deepwater Horizon Unified Command
Birds• Ingestion– Preening– Feeding
• Increased risk of hypothermia– Oiled plumage
Source: Deepwater Horizon Unified Command
Photo credit: Carolyn Shaw, LA Times
Thank You
Bryan FluechFlorida Sea Grant Extension Agent, Collier County
(239) 417-6210 [email protected]