While oil WAF can result in some mortality of coral
larvae, the concentrations at which this may occur are in
the upper range that could occur in the vicinity of an
undispersed oil slick. However, the likelihood of
contamination and coral larval mortality increases
considerably where the use of chemical dispersion raises
both the concentration and spatial extent of hydrocarbons
in the marine environment. Additionally, the chemical
dispersants themselves will enter the water column, either
in conjunction with oil or where the dispersant contacts a
clean water surface. This study clearly shows that
substantial impacts on coral reproductive success through
high levels of larval mortality may result from contact
with dispersed oil and dispersant. Additionally, this
larval mortality will occur within a short time period, and
at concentrations of dispersed oil and dispersant far lower
than may reasonably be expected to occur in a reef
environment where an oil slick has been chemically
dispersed. Therefore, dispersants should not be used in
the vicinity of coral reefs during coral spawning periods,
or subsequent planktonic larval development periods.