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conditions, of about 22 parts per m~llion (ppm).-

This level of dissolved hydrocarbons could be acutely toxic to many marine
organisms if it persisted in a localized area for a long enough period of
time. In laboratory tests, marine organisms suffered a 50% mortality
when exposed to concentrations of between 1.1 and 17 ppm over a 96 hour
period.

Dissolved hydrocarbons are, however, generally concentrated near the
water's surface and persist only until evaporative processes remove the low
molecular weight compounds. The rate of this loss is dependant on many
factors but is generally rapid. In most spills, elevated hydrocarbon levels
are confmed to the top meter of the water and usually do not persist
beyond several hours.

11. How sensitive are the biological resources of the Persian Gulf to oil
spills?

Although several ecological habitats and fisheries resources are at risk, the
effects of a major oil spill in this region are not likely to be profound
because these resources have survived and apparently rebounded from a
long period of oil spills.

Habitats at risk include coral reefs and sea grass beds; important resources
include -the dugong (a large marine mammal), sea turtles and shrimp.
Critical habitats in the region include sections of the coastline of Than and
United Arab Emirates. However, both of these regiofls~ are far enough
removed from the coast of Kuwait that the oil reaching these areas would
be substantially weathered and much reduced in toxicity. Therefore,
concern should be focused on important resources of the Northwestern
Gulf.  --

Coral reefs will likely survive a large oil spill unless use of dispersants
becomes- intensive and prolonged. There are small platform coral reefs
between Abu Ali and and Safaniyah off the Saudi Arabian coastline and
reefs north of Bahrain and Qatar. In 1980, a spill from a broken pipeline
off Ras Tanura impacted the coast of Balirain. No long term impacts on
the coral reefs could be detected. Recent mesocosm studies concluded that
healthy reef corals can tolerate relatively short (1- 5 day) exposure to both
fresh floating and dispersed Arabian crude oil with no observable long
term (1 year) effects on growth and colonization. Some coral mortality is
likely to result if dispersants were used to control the slick over a long


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