Inadequate monitoring of marine extinction

One reason there are so few marine species designated extinct or endangered is the difficulty of declaring with certainty that no example of a species exists anywhere in the vast oceans. Specialists can cite dozens of cases of marine life that have not been seen for decades, or even a century, but saying those species do not exist anywhere is a more difficult matter.
While the majority of conservationists are focusing on saving rain forests and other terrestrial ecosystems, marine specialists regard the endangerment of sea life as a slowly simmering crisis. Covering 71 percent of the earth's surface, fish, coral, mollusks, crustaceans, birds and other marine life are facing overwhelming threats from human activity.
In 1991, two researchers declared a Panamanian fire coral extinct but had to retract the declaration a year later after several examples of the species were located. Some species can become extinct without being noticed. In the mid 1990's researchers discovered the eelgrass limpet, a tiny snail that once flourished along the Atlantic coast of America, had been wiped out in the 1930's when a fungus destroyed its grass-like host plant.
(J) Problems under consideration