CHAPTER 19 & 20

OCEANS IN JE

OPARDY

Potomac

Rappahannock

York

James

Patuxent

Patapsco

Susquehanna

Chester

Choptank

Nanticoke

Pocomoke

THE CHESAPEAKE BAY

• largest estuarine system in the United States

• has a watershed of almost 64,000 square miles.

• This unique ecosystem also contains more than 1,500 square miles of wetlands that provide critical habitat for fish, shellfish, and wildlife; filter and process residential, agricultural, and industrial wastes; and buffer coastal areas against storm and wave damage.

THE CHESAPEAKE BAY

• Five major tributary systems--the Potomac, Susquehanna, Rappahannock, York, and James Rivers

• Major Problems facing the bay: Overfishing, Overharvesting, Nutrient Overload, Toxic Chemicals, Pollution, Habitat Destruction

“Clean Water Act”

Reading and Questions

POLLUTION

Ocean dumpingtrash – 17th annual Coastal Cleanup in September 20022.8 million lb. of trash and debris in 3 hours1.3 million cigarette butts and filters226,251 glass bottles238,826 metal cans2,529 syringes61% of trash collected was plastic82 animals found trapped in the debris

POLLUTION

Ocean dumping (continued)plasticstrength and durability of plastic make it one of the most hazardous materials in the sea

commercial dumpinggarbage, sewage and toxic chemicals have been dumped into the New York Bight since 1890

GARBAGE ISLA

ND

DOCUMENTARY

It is estimated there are more than 13,000 pieces of plastic litter on every square

kilometer of the ocean surface.

(1 Km= .6 miles)

THE WATERS OFF THE NEW YORK/NEW JERSEY COASTS WERE ONCE SO CONTAMINATED THEY WERE THE JOKE OF THE NATION. THE NY/NJ BIGHT WAS KNOWN AS THE "OCEAN DUMPING CAPITAL OF THE WORLD" DUE TO EIGHT OCEAN DUMPSITES. THIS MAP INDICATES THE LOCATION OF THESE OCEAN DUMPSITES.

POLLUTION

Ocean dumping (continued)military refusediscarded military hardware and munitions

toxic gases and chemicalsradioactive wastesdisposal of radioactive materials in trench subduction zones has been proposed

In 1964, mustard gas canisters are pushed into the Atlantic Ocean off New Jersey. Millions of pounds were dumped this way.

HUNDREDS OF DOLPHINS WASHED ASHORE IN VIRGINIA AND NEW JERSEY SHORELINES IN 1987 WITH BURNS FROM TO MUSTARD GAS EXPOSURE.

POLLUTION

Pollution via land and airurban pollution50% of the U.S. population lives within 50 miles of coastline (including the Great Lakes)

this population needs energy, industry and waste treatment

coastal seas and habitats are polluted by associated runoff from landpesticides, fertilizers, gasoline, oil, sewage, chemicals used to treat sewage

POLLUTION

Pollution via land and air (continued)pesticides and toxic materials from industrypesticides (e.g. DDT), toxic organic compounds (e.g. PCBs), heavy metals (e.g. mercury, lead, zinc, and chromium)

biological magnification—concentration of toxins in the tissues of animals as they are passed up the food chain without being broken down or excreted

POLLUTION

Pollution via land and air (continued)air pollutionsulfur dioxide from burning of fossil fuels can precipitate in water and lower pH

greenhouse gases (e.g. CO2, methane) contribute to global warming

global warning is thought to cause coral bleaching, raise sea levels, killing corals that must remain close to the surface to obtain sufficient sunlight for zooxanthellae

POLLUTION

Nutrient pollutionhuman wastesdisease agentscoliform bacteria, found in the intestines of many animals, are counted to monitor water quality

eutrophication – leads to blooms of phytoplankton and other marine microbes

increased productivitysometimes, the addition of sewage and animal wastes can boost the productivity of a marine community

POLLUTION

Nutrient pollution (continued)agricultural wastesfertilizers and animal wastes have effects similar to those of human wastes

pesticides are also found in runoff from farms

POLLUTION

Controlling pollutionlegislation was passed to prohibit dumping of sewage sludge or industrial wastes in the ocean after Jan. 1, 1992

largest threat is increasing coastal populations and improperly controlled commercial and residential development

THE 11TH HOUR

POLLUTION

Petroleum pollution

petroleum productscrude oil contains aromatic hydrocarbons and aliphatic hydrocarbons

aromatic hydrocarbons—molecules made up of carbon atoms in ring structures (e.g. benzene, naphthalen, cyclohexane)

POLLUTION

Petroleum pollutionpetroleum productsaliphatic hydrocarbons—straight-chain molecules (e.g. heptane, octane, nonane)

petroleum products are persistent, difficult for microbes to degrade, and toxic to organisms

POLLUTION

Petroleum pollution (continued)oil spillslargest oil spill in the U.S. was in March 1989, when the tanker Exxon Valdez ran onto a rocky reef 25 miles from Valdez, Alaska

largest and longest-lasting oil spill ever was in June 1979, when an offshore oil well in the Gulf of Mexico, the Ixtoc 1, blew out and caught fire

oil spills are deadly for marine organisms

POLLUTION

Petroleum pollution (continued)ecological effects of oil spillseffects on birds and mammalseffects on invertebrates and algaecommunity effects

BP OIL SPILL

BP OIL SPILL

210 million gallonsfar bigger than Exxon Valdez,

making it the worst spill in American history.

The National Wildlife Federation reports that already more than:

150 threatened or endangered sea turtles are dead

316 sea birds, mostly brown pelicans and northern gannets, have been found dead

POLLUTION

Petroleum pollution (continued)oil spill cleanupoil booms and oil skimmers help to confine the spill to a smaller area and recover some of the oilstraw is used to soak up the oil, then burneda bacterium genetically engineered to degrade crude oil is being tested

HABITAT DESTRUCTION

Wetlandsprovide nutrients, shelter and spawning grounds for a variety of marine organisms

have been drained, filled or dredged to provide more ground for industry, channels into ports/harbors, and beach-front real estate

legislation now protects wetlands, but the government continually changes the definition of “wetlands”

HABITAT DESTRUCTION

Beachesdirect effects of beach use and development on marine lifedisturbs nesting sites of birds, sea turtles and horseshoe crabs

destruction of habitatinterfering with natural processeslongshore currents—generated by waves that break at an angle to the beach, moving parallel to the beach

longshore transport process—transport of sediments by longshore currents

Oceans in Peril:

Overfishing

AN OCEAN IN CRISIS

The oceans are facing collapse due to overfishing.

According to the U.N. Food and Agriculture Organization 75

percent of the world's fisheries are now either overexploited, fully exploited, significantly depleted or recovering from

overexploitation.

Biggest single threat to marine ecosystems today is overfishing.

Overfishing: catching so many fish that too few are left in the ocean to reproduce at rates that can sustain a healthy population

Demand for fish is exceeding ecological limits with devastating impacts

Overfishing results in profound changes in our oceans

A large yellow fin tuna being cut up.

Yellow fin and big eye tuna may be commercially extinct in 3-5 years

BETTER CHOICES

Alaska King CrabCatfish (farmed)Clams Crab: Blue, Dungeness, KingCrawfishHalibut (Pacific)Mussels (Black, Green-lipped)Oysters (farmed)Pollack (Alaska)Prawns (trap-caught, Pacific)Rock Lobster (Australian) Salmon (Wild Alaskan)Scallops (Bay - farmed)Shrimp (US farmed)Squid (Pacific)Tilapia (farmed)Tuna: Pacific Albacore

END OF

THE LI

NE

EPILOGUE

• Natural changes are small and occur over long periods of time

• Changes caused by humans can be instantaneous and involve entire marine communities

• Understanding the underlying patterns and processes of the sea allows people to use the sea’s resources without jeopardizing its environmental or economic value for the future