INTRODUCED MARINE SPECIES IN PAGO ... - Bishop Museum

coral and reef growth, especially in the outer harbor east of a line between Goat Island Point and
Ava Point.
Outside of the harbor, corals and reefs flourish around the island of Tutuila and two areas have
been subject to considerable study and have been designated as areas for special management.
Fagatele Bay, a 66 ha embayment on the southwest coast, is relatively isolated from shore
access by steep cliffs and is recognized as a resource of high value (Thomas 1988). It was
formally designated as a National Marine Sanctuary in April 1986 and is cooperatively managed
by the American Samoan Government and the National Oceanic and Atmospheric Administration
(NOAA). Only traditional uses of Fagetele Bay are allowed, and activities such as spear fishing,
trawls, seines or fixed nets, and disturbance of the benthos are prohibited, along with discharge
of any materials or substances. The bay is therefore in a virtually natural state with little anthro-
pomorphic influence and is disturbed only by natural forces.
The other managed marine area on the island is the offshore zone of the National Park of
American Samoa, which extends from Fagasa Bay to Afono Bay on the north coast of Tutuila,
directly across the mountains from Pago Pago Harbor. This is one of the most scenic areas on
the island, and the park occupies land leased from native villages and the American Samoa
government. The National Park was authorized in 1988 and established in 1993, and along with
areas on the islands of Ofu and Ta‘u, encompasses about 4245 ha of land, beaches and sea,
with about one quarter of the total area lying under water. Only traditional fishing and gleaning of
the reef are allowed in the park. Two sites in the National Park on Tutuila were surveyed in the
present study, Vatia Bay, about one-third of the way from the Park’s eastern end, and Fagasa
Bay at its western end.
The present study involved detailed examination of the marine biota at six locations in Pago Pago
Harbor, an area that has been highly utilized for commercial and shipping activities for over 100
years, at two sites (Vatia Bay and Fagasa Bay) which have long been subject to traditional uses
and one area (Fagetele Bay) which has been relatively undisturbed by human usage. All of these
locations have had previous studies conducted that allow some degree of comparison of present
with past environmental conditions and the composition of their biotic communities. The focus
and purpose of the present study was to evaluate the biota for the presence and impact of
anthropogenically introduced marine species.
Transport of introduced marine species among world ports has occurred with increasing
frequency in the last 25 years, and introductions have sometimes produced substantial changes
in the marine ecosystems and fisheries economies of receptor areas (Ruiz et al. 1997, Ruiz and
Fofonoff 2000, Bax et al. 2001). Pago Pago Harbor is one of the major harbors in the central
South Pacific and potentially represents a regional center where marine species introductions
may enter and spread. Studies completed in Hawai‘i (Coles et al. 1997, 1999a, 1999b) have
shown that harbors on O‘ahu have been a major recipient of introduced marine species and that
new species continue to arrive. A total of 25 recently introduced marine and 15 new cryptogenic
species have been found in O‘ahu ’s commercial and military ports and introduced species have
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