Environmental Impact on a Samoan Coral Reef: A Resurvey of Mayor's 1917 Transect

Abstract

Coral reef sites in Pago Pago Harbor, American Samoa, for which descriptions and quantitative data were obtained by Alfred G. Mayor and the Carnegie Institution of Washington expeditions of 1917-1920, were resurveyed in 1973. Some sites were destroyed and others damaged in the intervening half century, but it was possible to relocate the major quantitative transect at Aua. A reduction in total numbers of corals, a change in the relative proportions of different genera, and a probable reduction in the average size of individual colonies are recorded. Elsewhere in the harbor, more drastic effects on the reefs were noted. Both human and natural impacts may be responsible for the observed changes; it is suggested that the Aua reef may now be recovering from earlier damaging events.