#Status of Coral Reefs 2002 - International Coral Reef Action Network

Status of Coral Reefs of the World: 2002
PALOLO DEEP NATIONAL MARINE RESERVE – STATUS IN 2002
This reserve on Upolu Island was established in 1974, and is the only recognised
marine reserve in Samoa (13°49 S; W171°45 W). It is also one of the first coral reef
protected areas in the world. The major feature is the ‘Deep’; a blue-hole (25m depth)
in the reef flat of the 137.5ha reserve, which also extends 500m out to sea to include
the fringing reef down to 25-30m. The unique part of Reserve is that the Deep
provides protection for corals and other organisms during cyclones and storms. This
protection is evident by the rapid recovery of the reef flats and slopes after two major
cyclones in 1990 and 1991, and severe shallow water bleaching in 1998 when waters
drained off the reef flat. The data below came from the few surveys by Ed Lovell and
Toloa in 1994, Foua Toloa in 1999, and Posa Skelton in 2002, with the Deep data
obtained by combining measures from two different, but comparable sites.
Sites 1994 (%) 1999 (%) 2002 (%)
Inshore Reef Flat
Live corals 28 4 42.0
Algae 35 56 41.5
Deep
Live corals 46 51 69.0
Algae 17 17 4.0
Outer Reef Slope
Live corals ‘0’ 91 57.8
Algae dominant organisms - 36.5
The destruction by the cyclones in 1990 and 1991 was so severe on the outer reef
slope that there were virtually no corals in 1994, and the area was dominated by algae.
At the same time the corals on the slopes of the Deep survived the storms (46%
cover), as well as some corals on the reef flat protected by the Deep. However, just 5
years later corals on the outer slope had recovered amazingly to 91% cover. But by
that time the reef flat corals had suffered 100% coral mortality in 1997 following
prolonged and extreme low tides during the El Niño event. Throughout these two
different damaging events, the Deep continued to act as a buffer protecting the corals
from damage and providing new coral larvae to colonise the damaged areas.
In 2002, the live coral cover at all the sites in the reserve averaged 60% and 34% algae.
Outside the Reserve, the outer slope near Vaiala village had 10% cover at one site,
which was dominated by a large bed of brown alga (Spatoglossum sp.), and 96% cover at
another, with the average of 51% cover (similar to the Reserve). Some corals were
affected by a coral disease and a few crown-of-thorns starfish were seen, but generally
the area appeared very healthy. The same, however, cannot be said about the fishes as
there is evidence of over-fishing. The lack of big fishes was obvious, with low fish
diversity and abundance at all sites. The dominant fishes were damsel-fishes along with
some algal grazers, especially surgeon fish (Acanthurids). The reserve is managed by
the Samoan Government Division of Environment and Conservation with an on-site
manager. Monitoring and further studies are planned in the Reserve to provide the
administrators with ammunition to improve the management. From: Posa Skelton,
International Ocean Institute – Australia; Posa.skelton@impac.org.au
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