| Oil Spills
of debate have not resolved the United States public policy issue: "Should
we allow for drilling of oil in Alaska's Arctic National Wildlife
Refuge?" To people concerned about oil-spill accidents,
such drilling and transporting of oil threatens the areas' rich ecology.
Oil-spill victim. Source: NOAA
safely in the Artic refuge now are bears, wolves, foxes, musk oxen, millions of
migratory birds, and a 130,000 caribou herd. These animals, and
the plants too, can be harmed in three different ways: 1) direct contact, 2)
poisoning after ingestion, and 3) destruction of habitat.
To people concerned
about energy consumption in the U.S. and about the country's dependence
on unreliable foreign sources, drilling in the Alaska
Refuge could supply all the oil we use over six months to two years.
Are oil spills
common? The U.S. Environmental Protection Agency says there are about
70 per day. Typically, these are small and do no serious harm. But
big spills do occur sometimes, and the damage to ecosystems can be very
What to do?
This is not the place to discuss world politics or even U.S. government
energy and environment policy. There is a strong argument for drilling
for more oil, especially now that we have newer drilling techniques that
reduce the chances of accidents. But in this ecology lesson, the appropriate
thing to do is to learn about what oil spills can do to the environment.
How Have Spills Occurred?
- Spills from
- Pipeline breaks
- Tanker ships
running aground, hitting iceberg (1989 Exxon Valdez accident)
- Noise of drilling,
trucks, pipes banging, etc.
- Roads to bring
in equipment and workers, haul out oil
What Is It In Oil That Is Hazardous?
- Fumes are irritating
to eyes, nose, mouth and lungs
- If burned, contributes
CO2 to global warming and to sulphur- and nitrogen-based gases
that cause acid
- Mechanical effects
- clumps settle
out on ocean flood, covering up habitat
air space in fur and feathers (see below)
The Good News
drilling and oil handling technologies reduce chances of oil
- Oil spills
can be cleaned up
and bacteria degrade oil into less-harmful compounds
on Wildlife Behavior
- Home range
may be reduced (caribou don't like the noise at drilling
nest in the waste dumps - foxes, ravens, and gulls feed
on their eggs. This spreads toxins across species.
that get oil on feathers cannot fly and can't get to food and
Losses in the Exxon
in Alaska in 1989
- 15,000 otters dead
- 36,000 sea birds dead
- 100 bald Eagles dead
of Bad Effects
Cleaning Up An Oil Spill
(from eating oil-contaminated plants and animals)
contains cancer-inducing PAH (polycyclic aromatic hydrocarbons)
- Sea Otters, other Marine Mammals Without
the fur, collapses air spaces, makes it hard to keep warm
compounds in oil can kill the eggs or juvenile stages
on gills interferes with gas exchange
growth, fin erosion, cancer in sensitive species
on feathers collapses the air space between feathers that keep birds
warm and buoyant. Ingesting
oil by cleaning themselves or eating oil-contaminated food can cause reproductive
disorders, red blood cell deficiency (anemia), pneumonia
on eggs lower hatching rate
Some have died from
grooming oil off their fur
- Invertebrates (intertidal)
Many are killed by
for bottom dwellers when oil settles
Spawning grounds may
grass, mangrove, and some intertidal plants can be killed by oil
scoop or suck up as much as you can, disperse or dilute the rest
to trap the oil
boats to gather oil and transfer to barges
pads to soak up oil
- Fire -
burn off the oil
- coagulating agents to make it clump for easier pickup
- Water -
spray beaches to move oil into collectible pools
- some species "eat" oil
and waves will disperse oil
can see the use of absorbent mops after Valdez accident. These mops
soak up to 70 times their weight of oil.
|The photo above
shows workers washing the shore line after the Valdez oil spill.
This removed the oil, but probably also destroyed many organisms
living on the beach.
to protect salmon hatchery from oil spill.