Transcript
Larger fish were able toswim away from the oilduring the spill.
MummichogsAlso known as killifish,mummichogs canbreak down petroleumhydrocarbons and excretethem as carbon dioxideand water moleculesthrough their digestivesystem. Their egg has a tough outer membrane,which may keep oil frompenetrating and damagingthe embryo.
Fish that feed on creaturesthat are directly affectedby the oil spill will be moreat risk for toxin-relatedproblems than fishfeeding on plankton withinthe water column.
Horseshoe CrabsMost adults have migratedto the continental shelfin the Atlantic. When thewater warms, they will returnto spawn in the Delaware Bay.
Adult and juvenile crabs that do not move offshorecould encounter tarballs on thebay’s floor and become oiled.
If oil or tarballs are on the beachesor in the sediment duringspawning, they could affect the survival and development of the crabs’ eggs and larvae.
Green alga
Goldenbrown alga
Herring egg
Oyster larvae
Striped bass larvaGiant water flea
Barnaclenauplius larva
Copepod Crab zoealarva
Sea nettleephyra
Snail larva
Diatom
American eel
Blue heron
Silver-haired bat
Baldeagle
Osprey
American shad
Flounder
Oyster Bed
Catfish
New Jersey chorus frog
Coastalplain frog
Mud turtle
Horseshoe crab
Atlantic sturgeon
River otter
Diamondbackterrapin
Tigersalamander
Beltedkingfisher
Benthic community species magnifiedSpecies are not to scale
Mallard duck
River herring
Menhaden
Red drum
Sheepheadminnows
Mummichog
A Drop of Fresh WaterPlankton are tiny plants, animals or bacteria andserve as the basis of the food web. They float in the water column and are sensitive to changesin water quality. There are many different speciesin the Delaware estuary.
Phytoplankton are capable of photosynthesis and live in the part of the water column that lightcan penetrate. They are single-celled organismsthat include diatoms and other algae and areconsumed by zooplankton. Contaminants canenter the food web at this level.
Zooplankton are filter feeders that get foodfrom particles suspended in the water.Since zooplankton consume phytoplankton,they are an important link in the food weband can convey contaminants to fish.
BirdsMore than 300 species of birds are foundin the Delaware estuary.
Only a fraction ofthe birds immediatelyaffected by the oil spillwere recovered andcleaned, and survivedto be released.
During the nestingseason, oil that comes in contact with an eggcan permeate the shelland kill the embryo.
Oil was seen on someof the three pairs of nesting bald eaglesalong the Delaware River.The nesting area, hardhit with a heavy coatingof oil, was given a prioritystatus for the cleaning.
Larger Water FowlCanada geese that are slightly oiled maybe able to fly away from the spill area.During preening or feeding, they caningest oil and become sick.
Mussels function as biofilters.This can lead to a toxicconcentrationof oilbyproducts in their fatty tissue.As withoysters,mussels can beaffectedby direct exposureto their tissueand smothered by heavy crude oil.
VegetationThe wetlands that ring theDelaware estuary are vital
to maintaining cleanwater and a healthy
ecosystem. They area spawning andnursery area for
fish and helpremove nutrients
from the watercolumn.
Mallards and wood ducksfeed on small invertebrates andsubmerged vegetation by siftingsediment through their bills.
Fiddler CrabsStudies of the fiddler crabafter an oil spillin Massachusettsuncovered behavioralproblems. The crabs livein burrows in marsh areas.During warm weather,they come out at low tideto eat and mate.In the winter, they burrowdeeper to hibernate. Afterthe oil spill, the crabsstudied did not burrowdeeper and froze over the winter.
Oyster BedEastern oysters werein a period of inactivity duringthe colder months, so theywere not feeding as much atthe time of the spill. As withmussels, the oysters can ingestoil particles during feeding.
Red KnotsThe endangeredbird eats the eggs of the horseshoe crabduring a stopover on its migratory path to the Arctic.
Canada geese
Loggerheadturtle
Migratory TurtlesThe loggerhead, Kemp’s ridley,leatherback and green turtleswill migrate to the bay areain the spring. Any effect fromthe oil would most likely comefrom eating contaminated prey.Loggerheads’ diet includeshorseshoe crabs.
Benthic CommunityBenthic algae, microorganisms growing on the bottom sediment of the water body,are a source of food and habitat in the marsh area. The benthic communityincludes tiny worms, isopods, clams, mussels, shrimp, snails and crabs that live in thebottom sediment of the estuary. Filter feeders, such as oysters, siphon their foodfrom the water. Deposit feeders, such as snails and shrimp, sift through the rich soiland feed on the organic matter.The eggs and larva of fish that spawn on the river bottom or in vegetation wherethere are still concentrations of oil may be killed or suffer deformities and impairedgrowth from the toxic effects of the oil.Some oil can seep into holes left by burrowing worms, mussels and plant roots.Once in these subsurface areas, the oil will be covered by the sediment during the back-and-forth motion of tides.
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TACONY-PALMYRA BR.
BETSY ROSS BR.
B. FRANKLIN BR.
DEL. MEM. BR.
WALT WHITMAN BR.
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PENNSYLVANIA
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NJ. TPK.
A 10-mile stretch of the shipping lane was closed and restrictions were temporarily placed on larger vessels in the river after the oil spill. Ships in the area at the time needed to be cleaned before leaving the river.
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Delaware River Shoreline Oiling
LightVery LightMediumHeavyUnsurveyed
Oiling
MILES
0 5*Map represents data as of Feb. 23; map does not represent precise amounts or locations of all the oil spill
SALEM
Delaw
are
Rive
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GLOUCESTER
CAMDEN
BURLINGTON
PHILA.
DELAWARE
CHESTER
DELAWARE NEW JERSEY
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Site of oil spill
Oil trench sites
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■ Command center closed in April.■ Various vessels are continuing to monitor and maintain the affected areas.■ 221,910 gallons of oily liquid have been recovered.■ 17,761 tons of oily solids (cleanup materials and oil) have been collected.■ 389 birds have been released and 186 birds are reported deceased.■ One year after the spill the Coast Guard has declared the spill cleaned except for a 200-yard stretch in Paulsboro, the site near the spill.
Oil Spill Facts
The Venezuelan crudefrom the Athos I spill is veryviscous and sticky, like peanutbutter. It is used to make asphaltand weathers slowly.
Oil will rapidly spreadto a thin film on thewater surface.
Pooled oil accumulates insubsurface depressions.In the Athos I spill pooledoil was found at thecollision site.
Cleaning Up the Spill
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100
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200
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300
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(1975–2004)In thousands of gallons
Major Oil Spillsin the DelawareRiver and Bay
Athos I
’04
B-115
’99
CoastalOil
Eagle
’95’89
GrandEagle
’85
Corinthos
’75
PresidenteRivera
Fiddler crab(male)
Evaporation
Looking Ahead
Before
The oil binds with sediment particles as it saturates the ground. This requires cleanupcrews to remove particles and the oil together.
During After
Ground-Saturation Removal
oil
soilparticle
BoomsWithin a week of the spill,91,100 feet of boomswere set out along theshoreline and in sensitiveareas to combat spread.
SkimmingBoats used booms to collectoil from the water surface.
V-SORSThe Vessel-SubmergedOil Recovery Systemis a pipe with attachedchains and snares,composed of thinsheets of absorbentpolypropylene. It islowered into the waterand towed at lowspeeds by a boat tocollect oil on the riverbottom.
Submerged oilrecoveryA work platformwith a craneand a submersiblepump is loweredto the site of pooledoil. A diver uses a maneuverable nozzleand siphons the oil intodecanters on theadjacent barge.The oil is thenstored in containers,and the water isdischarged into aboomed area.
Warmer WeatherWhen the temperature rises, oil becomes softer and “re-oiling events” or “seeping”may occur. Cleanup officials consider dredgingthe oil to be a last resort, since it would likelyreintroduce pollutants from sediment such aslead and mercury into the water column.
The cost of cleanup is $175 million, of which $125 millionis from Tsakos Shipping, owner of Athos I. The remaining$50 million is from the Oil Spill Liability Trust Fund.Responders were allowed to usevarious removal methods.
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The oil’s chemical ingredients,hydrocarbons, will changeto a gaseous form and evaporateshortly after the spill. This cancontribute to air-quality issues.The smell of oil at the sceneis evidence of this evaporation.Precipitation will return thehydrocarbons back to the land.
The National Oceanic and AtmosphericAdministration Damage Assessmentand Restoration will release atechnical data report scheduledfor release in 2006.Absorption
Oxidation, a chemical reaction that occurs whenthe oil is exposed to air, will increase the densityof oil and cause it to sink. Oxidized oils are moretoxic to aquatic life. Tarballs may persist forseveral months. Some have reached the shorelineas far as the outer coast of the Delaware Bay. Tarball
The effects of the Athos I oil spill: On Thanksgiving weekend last year, the Greek tanker spilled an estimated 265,000 gallons of a thick Venezuelan
crude oil into the Delaware River • More than 215 miles of shoreline in the Delaware estuary were contaminated with oil • The spill happened when
most animals were prepared for winter and many plants were dormant • Migratory fish, birds and dolphins had already left
for warmer climates • While some of the damage was seen immediately, scientists worry that
the hidden effects could harm the environment for decades.
ImbalancedA Natural World
TurtlesAdults can survivea spill if steps are taken to cleanthem. Not so for babyturtles. Offspring thatwere cleaned andrehabilitated in theFebruary 2000 oilspill at the JohnHeinz NationalWildlife Refuge atTinicum were borndeformed or died.
SOURCES: Thomas L. Bott, Ph.D., Stroud Water Research Center; Delaware River Basin Commission; Dr. Susan E. Ford, Haskin Shellfish Research Laboratory; Susan Soltau Kilham, Ph.D., Department of Bioscience andBiotechnology, Drexel University; Danielle A. Kreeger, Ph.D Delaware Estuary Program; Dr. Richard Larsen, Professor Emeritus, Department of Natural Sciences and Environmental Resources, University of Illinois at Urbana-Champaign; Ed Levine, James Hoff, NOAA; O'Brien & Gere; Christopher K. Sommerfield, College of Marine Studies, University of Delaware; James Spotilla, Ph.D., Department of Bioscience and Biotechnology, Drexel University;Suzanne Thurman, Marine Education, Research and Rehabilitation Institute (MERR); Tri-State Bird Rescue & Research, Inc; Maya K. van Rossum, Delaware River Keeper; U.S. Coast Guard; U.S. Fish & Wildlife Service ■ BOOKSDataStreme Ocean, American Meteorological Society, 2004; Life in the Chesapeake Bay, Alice Jane Lippson & Robert L. Lippson, 1997; Living Resources of the Delaware Estuary, Delaware Estuary Program, 1995; The ScientificCharacterization of the Delaware Estuary, Delaware Estuary Program, 1996; Sources, Effects and Sinks of Hydrocarbons in the Aquatic Environment, The American Institute of Biological Sciences, 1976; Angler's Guide to Fish, 1997;The Audubon Society Field Guide to North American Birds, 1977; Atlantic & Gulf Coasts, 1988 KEITA S. SULLIVAN and MARI A. SCHAEFER / The Philadelphia Inquirer
SoilThe soil is made
of more complexmaterial than a rockyor sandy shorelineand is a source
of nutrients for plants.
A6 B www.philly.com THE PHILADELPHIA INQUIRER Monday, November 28, 2005 THE PHILADELPHIA INQUIRER www.philly.com A7
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