Botkin Environmental Science Earth as Living Planet 8th txtbk

Case Study: The Oil Spill in the Gulf of Mexico in 2010 553
How does this compare to other blowouts and oil
spills? The largest known blowout on land, which happened
in Iran in 1956, involved about 120,000 barrels per
day and lasted 3 months before being capped, releasing
a total of almost 11 million barrels. A number of other
“gushers” in the history of oil drilling released about
100,000 barrels per day. (We discuss other spills on land
and offshore in Chapter 15.)
Any way you look at it, the BP spill is a lot of oil
released into the Gulf’s fragile marine and coastal environments.
Spilled oil that remains near the water surface
moves with currents and winds, some of it ending up on
shorelines, partly covering plants and animals, infiltrating
the sediment, and doing other kinds of ecological damage
(Figure 24.2). Although most effects of oil spills are
relatively short-lived (days to a few years), previous marine
spills have killed thousands of seabirds, temporarily
spoiled beaches, and caused loss of tourist and fishing revenues.
Complicating matters, four species of sea turtles
(loggerheads, Kemp’s ridley, leatherback, and green) lay
their eggs along Gulf State coasts that either have already
been reached by the oil or are likely to in the near future.
By June 25, 2010, 555 turtles had been found within the
spill, 417 of them were dead. 2
(a)
(b)
(c)
(d)
(e)
FIGURE 24.2 Oil on land: (a) Chandeleur Beach, Louisiana,
2010; (b) oil invades a Louisiana coastal wetland marsh in 2010;
(c) dolphins swimming through some of the BP oil spill; (d) Kemp’s
ridley sea turtle at a rehabilitation center; (e) oil-covered seabird in
Louisiana.