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Oil on the Rocks
An ongoing marine census may yield new
insight into the destruction wreaked by oil spills. Rachel
Tompa gets her feet wet. Illustrated by Tina
Fuller and Lila Rubenstein.
Illustration:
Tina Fuller A small black stain marks the
craggy gray rock. Its almost indistinguishable from the dark
splotches of snails and algae on this rocky shore in Santa Cruz,
but Christy Bell notices it. Oh, theres a tarball, she says
offhandedly. Flattened and hard, it looks like old gum. Soon Bell
finds more streaks and globs of tar near the crumbling stairs from
the road. The tarballs feel both rough and smooth, gritty with
sand, but their round edges betray a liquid past. Now they are
essentially asphalt, Bell says, identical to the road 20 feet
away. Many similar tarballs now dot the
shores of San Francisco Bay and the
surrounding coast. They were once oil on a container ship bound
for South Korea. Now, instead of powering the 900-foot Cosco
Busan across the Pacific, the blobs mar rocky shores inside
the bay and between Half Moon Bay and Bolinas. On November 7, 2007,
they spilled into the bay in a torrent of nearly 54,000 gallons of
heavy fuel oil. The ship had collided with the Bay Bridge in a
dense fog, ripping a giant gash in its hull. On
the grand scale of spills, this was minor. The 1989 Exxon Valdez spill
in Alaska was about 200 times larger. Still, it struck sensitive
habitats in a major metropolitan area, and the damage isn't yet
fully known. More pools of oil might dwell on the ocean floor or
behind boulders on rocky shores like this one, where Almar Avenue
meets the Pacific Ocean. Here Bell, a
research technician at UC Santa Cruz, describes what she saw during
the hectic days following the Cosco Busan spill. She is
part of a group led by marine ecologist Pete Raimondi studying the rocky
intertidal, the communities of creatures between high and low
tide. Raimondi and his fellow researchers have spent nearly two
decades counting organisms to gain clearer focus on the slimy world
of intertidal life from Alaska to Baja, California. This dank and dynamic ecosystem is sensitive to
oil spills and other manmade catastrophes. Many intertidal citizens,
such as mussels and other shellfish, are at the bottom of the marine
food web and especially prone to damage. But to help the recovery,
researchers must first uncover what was harmed. With their ongoing
censuses, Raimondi and Bell are in a unique position to understand
how oil affects the intertidaland to advise biologists how to pick
up the pieces after Cosco Busan. In
the event of an oil spill The crash was
no surprise to Raimondi. Wed been waiting for an oil spill for the
last 17 years, he says, dating to the Exxon Valdez
disasterwhen nearly 11 million gallons of oil fouled Alaskan waters.
While not the largest spill in history, it arguably was the most
destructive, due to the tankers rupture in pristine Prince William
Sound. Scientists realized they might never
know the extent of that spills damage. Secondary effects, such as
the death of a starfish from eating oil-slicked mussels, are almost
invisible. The hard part of our job is trying to attribute cause
and effect, Bell says. Sometimes its obvious, when a bird is soaked
in oil and cant fly. But when small animals or microscopic critters
quietly drop off the radar months or years after a spill, its
different. And scientists did not have a good picture of communities
in Prince William Sound, making it impossible to know what had
disappeared. Raimondi and his colleagues
realized that if a major spill hit California, they would be no
better off. Previous researchers had studied intertidal creatures,
but nobody knew how many of each species lived where, and whether
there were natural fluctuations. So in 1991, funded by the U.S. Minerals
Management Service, they began studying the states coastal
communities. In their ongoing monitoring, the researchers lay out
grids of tape in fixed locations on the coast. They tally 13 target
species of algae and invertebrates in the grids, visiting a few
times a year. The targeted species, found up and down the coast,
include mussels, barnacles, abalone, and others sensitive to oil.
Back on dry land, the scientists put these numbers into a large
database that tells them how many of each organism lives where, and
when. They can use the database to track the rise and fall of a
particular species all along the coast, or to look at all species
in one spot. The surveys yield a general
picture of ecosystem health, says biologist and intertidal surveyor
Mary Elaine Helix of the Minerals Management Service. Its like
going to the doctor. You take the blood pressure, and you take the
temperatureit doesnt really tell you whats wrong with you, but it
tells you if something is wrong, she says. Regular monitoring of
an ecosystem's normal "vital signs" is important in the
highly variable intertidal, where scientists must distinguish
seasonal variations from death by unnatural means, such as oil
spills or climate change. Since it began,
the project has grown from nine field researchers to about 100, and
from nine sites in Santa Barbara County to about 100 sites between
Alaska and Baja, California. This gigantic projectoverseen by the
Multi-Agency Rocky Intertidal Network, or MARINe,
and the Partnership
for Interdisciplinary Studies of Coastal Oceans, or PISCOis
peerless in age and geographic range. The amount of time theyve
been conducting surveys out West is phenomenal, says Jeremy Long, a researcher
at Northeastern University who has started a similar project at two
sites on the East Coast. Its absolutely essential to collect that
kind of long-term data, and their program does it. After the November 2007 spill, Raimondis team
visited 17 sites in San Francisco Bay and the surrounding coast to
assess the spills immediate effects. They modified their approach
to gauge the extent of oiling as quickly as possible: They took
digital pictures while the oil was still fresh, instead of counting
creatures on site. Later, other researchers will count the targeted
species in the photos. Not all of the current
research anticipates oil spills. By keeping a finger on the
shorelines pulse, MARINe scientists can see other changes. For
example, the surveys revealed that black abalone populations were
crashing in southern California (see sidebar).
Raimondis group also monitors changes in red abalone population at
Stornetta Ranch in Mendocino County, which recently became public
land and is now more accessible to abalone harvesters. However, spills are on Raimondis mind. Years of
meticulous census-taking to prepare for a repeat of Exxon
Valdez on the West Coast may seem pessimistic, but months after
the Cosco Busan spill, hes already expecting the next one:
There's so much [tanker] traffic that it just seems like a matter
of time before something like this happens again." Slimy versus sticky It could be years before they understand the
Cosco Busan spills long-term effects, but Raimondi and
Bell have amassed clues from a previous study. The floor of the
Santa Barbara Channel, which runs between mainland California and
the Channel Islands, constantly leaks oil that washes ashore. In
some places down there, this part of the intertidal would be like
standing on blacktop asphalt, Bell says, gesturing at the high-tide
zone.
The intertidal is this narrow
band that goes through such extreme physical conditions, Bell says,
waving her arm from the high, drier intertidal to the low intertidal
zone, which right now is mostly underwater. Its such a dynamic
area. Different creatures adapt to different conditions in ribbons
of the intertidal. From a distance, the rocky shore appears striped.
The wet, low intertidal is bluish-black with mussels. Farther from
the water, patches of barnacles and turf algae make a brown stripe.
Bell and Raimondi noticed that the natural oil
near Santa Barbara stuck around longer on barnacles in the dry upper
zone. They wondered whether the oil stuck to barnacles preferentially
because of their rough surfaces, or whether the barnacles were just
in the wrong place at the wrong time. Using dental molding material
and Tupperware sandwich containers, Bell made plastic casts of
barnacle beds and placed them in different spots in the intertidal.
Over the next 18 months, Bell checked her
pseudo-barnacles for oil. She found that some species, such as
rockweed, were untouched even where barnacle casts in their midst
were oiled. Rockweed oozes mucus from its tips, which probably
sloughs off oil. But in mussel beds close to the water, constant
surf washed oil off of both casts and mussels. So the degree of
oiling depends both on the texture of the affected species and
external conditions in its zone. As for the barnacles, oil can
cover their mouths, preventing them from feeding. If that gets
coated over, it can kill them, Bell says. However, Bell also noticed
that new barnacles sometimes settle on top of weathered tar.
Raimondis group saw similar variability after
the Cosco Busan spill. In initial surveys they did not
see much oil on slimy things such as rockweed, but they saw more
on textured critters such as barnacles and some other kinds of
seaweed, as well as on mussels and crabs. Where oil sticks, it
hurts, but sometimes it can damage even if it doesnt stick. Even
though mussels are quickly washed clean by the surf, they are still
sensitive to oil, Raimondi says. His group collected mussel and
other shellfish tissue samples for analysis to determine how much
toxic chemicals they absorbed from the oil. Mussels are a critical
part of the whole marine community, because so many predators eat
them, such as starfish, otters, and people. When they go, says
Raimondi, a lot of other animals go with them. How is a mussel not like a car?
Several of the sites Bell and Raimondi visited
were not yet cleaned. At China Cove on Angel Island, Bell says,
you could just see it from a distance. It was like this iridescent,
bluish film on the shore. In other places, such as at Point Isabel
in El Cerrito, there was thick, black oil on the rocks. It looks
different than it actually feels, Raimondi says. It looks like
there's just hot tar on everything, meaning it almost looks liquidy.
Its shiny. But when you actually touch it, it's pretty solid.
Maybe a little bit sticky, but not as sticky as you'd think.
When oil washes up on shore, its important to
clean it before it gets back into the water and hits birds and
marine mammals. Cleanup crews can use either absorbent pads or
high-pressure sprays, like those in do-it-yourself car washes.
Using pads is arduous work. They sort of pat surfaces, Raimondi
says, pretending to blot his desk with a piece of paper. The
manpower involved is astounding. There would be people out there
patting the rocks, soaking it up on rags and throwing the rags away,
and everyone has to wear these [special] suits. On the other hand
you go in with a steamer and boooogghhhhhh, he adds, blasting an
imaginary cleaner over the piles of books, rain jackets, and towels
in his office. The pressure cleaners work
so well that they can clean the intertidal to death. It emulsifies
everything, Raimondi says. You go through these areas and its just
like mush. The high-pressure spray churns up oil, sand, and rocks,
launching mussels, barnacles and other creatures into the air and
killing them. The mixing leaves behind an environment inhabitable
for new generations of shellfish. Studies
on clam beds oiled by the Exxon Valdez spill found that
it could be up to 70 years before the pressure-cleaned beds recover,
compared to five to seven years for uncleaned beds. In fact, cleanup
crews used pressure cleaners sparingly following the Cosco
Busan spill, because of their known damaging effects. "It's
looking like not cleaning at all is a pretty good option for some
organisms and some habitats, Raimondi says. Waiting to respond Raimondi might have seen even more oily sites had
he gone out earlier. When the oil spill occurred, I expected a
call almost right away, because we were a responding group on paper
to assess the rocky intertidal, he says. But the call didnt come.
With some help from the U.S. National Park Service, the group
finally got clearance to survey. But when they got to the sites,
safety officers turned them away. By the time all the bumps were
ironed out, more than three weeks had passed. "That was way
longer than it should have been. It should have been six hours,"
Raimondi says. Mary Elaine Helix, who was
part of the incident command running the oil spill response, agrees
the delay was unfortunate. She says field safety officers didnt
realize the biologists were familiar with the rocky shoreline, so
their safety regulations may have been too cautious. There was a
disconnect, Helix says. Weve been putting things in place so that
shouldnt happen next time. Oil-spill damage
assessment usually comprises several steps. If researchers are
quick, they can survey sites before oil even touches shore. The
next step is to assess immediate damages, after oiling but before
cleanup. Raimondis group missed step one entirely and some of step
two, since some of their sites had already been cleaned. Still
left are injury assessments, which could mean waiting weeks or
months for the oil to do its worst, and recovery, which could take
years or more. Raimondis frustration is
evident. We knew the science, we knew where to go, what to do, he
says. It was really a little bewildering to me how there was that
level of miscommunication. How much
for that barnacle? Still, Raimondi
and the other MARINe researchers are well positioned to understand
how oil affects the intertidal. Its not just an academic exercise:
The data Raimondis group collected after the spill will help put a
dollar amount on damages for a mitigation settlement. Its like if
someone rents an apartment and they trash it and dont pay the rent,
says Steve Hampton, resource economist with the California
Department of Fish and Game. Just having them clean the apartment
is not enough. They need to also pay the lost rent. Cosco
Busans owner, Regal Stone, will pay damages to the intertidals
landlord, the state of California, for cleanup and restoration.
For example, a 6,800-gallon spill in
Santa Barbara in 1997 netted a $1.9 million settlement from the
responsible party. Based on preliminary
data, Hampton estimates that 50 miles of rocky intertidal were oiled
by the Cosco Busan spill. We might be hard pressed to
find enough restoration for all of it, he says. Helix is running
trials to reseed decimated mussel beds with new mussels scraped off
oil rigs. Raimondi thinks removing litter also might help. "When
we went to these areas, even isolated shorelines and islands, there
was so much trash and debris that compromised the community probably
more than the oil did," he says, shaking his head. "There
were engine blocks and lawn chairs. It was really astoundingly
dirty." Because of their involvement
with the settlement, Bell and Raimondi are reluctant to go beyond
scientific assessments. Bell says she cant talk about her opinions
on the spill. Back on the shore in Santa Cruz, when asked if it
was difficult to see oil on familiar sites, she is taken aback.
Thats a hard question, she says, and hesitates. Its never nice to
see oil like that. She presses her lips together and looks away.
Top
Sidebar: The
Black (Abalone) Death | Illustration:
Lila Rubenstein | Black
abalone once carpeted some California and Mexico shores. Now
the majestic sea snails, which occupy the low intertidal between
Cabo San Lucas in Baja, California, and Mendocino County, are
relegated to the odd rocky crevice. Aided by rising ocean temperatures,
a persistent and deadly bacteria is slowly marching north, leaving
scores of abalone dead in its wake. Scientists
with the National Park Service first noticed dwindling populations
on the Channel Islands following the El Nio weather pattern of
198384, but the bacterial disease appeared limited to these areas.
Pete Raimondi, marine ecologist at UC Santa Cruz, and fellow
researchers later noticed that the disease had spread further.
Between fall 1992 and spring 1993, black abalone at his research
site in Santa Barbara crashed from nearly 100 to a single specimen.
The shellfish fell prey to withering foot syndrome, a gut
bacteria that inhibits digestion. The abalones foot, which normally
protrudes from the edge of its shell, shrinks as the animal
starves. Black abalone were so prevalent
in Southern California that they were primed for a big event like
this, says Christy Bell, a research technician in Raimondis lab.
Its like the plague. Raimondi later observed
crashes spreading from south to north. By 1998, the withering
plague had reached Cayucos in San Luis Obispo County. The bacteria
exists in all abalone populations, although its deadly effects are
hampered by colder water. Black abalone populations crashed in
1988 at Diablo Canyon in San Luis Obispo County, probably because
of warm run-offs from a neighboring power plant. Now, the U.S. Environmental Protection Agency may
put the shellfish on its endangered list. Raimondi is not sure
this change in status will offer more protection. Most species on
the list have lost habitat because of human activity. But the
abalones decline is not directly attributable to humans, and it's
already illegal to harvest them. Abalone
offspring settle near their parents and are subject to the same
diseases, so Raimondi believes biologists must take active measures
to save them. Ironically, he worries that endangered status could
make restoration efforts more difficult by forcing scientists to
obtain permits to work with black abalone. Top
Biographies Rachel Tompa B.A. (biology) University of Chicago Ph.D.
(biochemistry and molecular biology) University of California, San
Francisco Internship: University of California, Berkeley news
office My mother used to call me her little Renaissance woman because
I had so many different interests. I eventually gravitated toward
biology, but I found myself wanting to be a botanist one day and a
paleontologist the next. After college, I tried to settle down and
be a molecular biologist. But my lab bench, with its sometimes
failing and often puzzling experiments, held little allure. I was
happier at seminars or hanging around other labs, looking for a
quick fix of cool science from my colleagues discoveries. Science
writing struck me as the perfect way to both ensure a steady supply
of interesting science and indulge my Renaissance side. Im eager
to trade microliters for words as my new tools of exploration.
. . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . Tina
Fuller B.A. (painting) University
of California, Santa Barbara While
working towards my degree from the College of Creative Studies at
UC Santa Barbara, I was continually compelled to incorporate botanical
and natural science elements into my work. This led me to a natural
and thrilling transition to the world of scientific illustration.
Having completed the most inspirational and enjoyable year at the
Scientific Illustration Program, I cant wait to experience what
lies ahead in this field. I'm currently in Oahu working with the
Lyon Arboretum. .
. . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . .
. . . . . . Lila
Rubenstein B.A. (environmental
studies and art) University of California, Santa Cruz
I am passionate about illustrating topics
concerning current environmental and social issues. I have spent
a significant amount of time studying art and science at UC Santa
Cruz. Life after the Science Illustration Program finds me living
in New York City and working for Scientific American.
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