MACGILLIVRAY

This reef has been surveyed using manta tow since 1986 when it was classified as Recovering from previous COTS activity. Reef-wide live coral cover remained at a high level until 1994. In 1993 elevated COTS populations were recorded and the reef was reclassified as Incipient Outbreak. COTS remained at or around Incipient Outbreak levels on this reef until 1998. There was then a corresponding gradual decline in reef-wide live coral cover to moderate (10-30%) levels in 1998. Since then, coral cover has remained moderate (10-30%). No bleaching, disease or COTS were recorded during manta tow surveys in 2003 and the reef remained classified as Recovering.

This reef has been surveyed extensively since 1986 when it was initially classified as Recovering from previous COTS activity. Coral cover remained at a high level through 1986 to 1994. In 1993 elevated COTS populations were recorded from this reef and the reef was reclassified as Incipient Outbreak. No bleaching or COTS were recorded on this reef in 2000 and it is now classified as Recovering. Coral cover is currently moderate (20-30%). On the north-east flank of this reef, cover of hard coral has remained stable at moderate levels and in the year 2000 cover averaged 18% . The stability of the benthic community at this reef may be due to the dominace of slow growing, massive Poritidae. Cover of this family has remained constant at approximately 10%. Cover of soft coral and algae have also remained stable and in 2000 averaged 5% and 52% respectively. In the 1998 survey several taxon showed positive trends in abundance, most of these however, peaked in either 1996 or 1997. As was first shown in the 1999 survey and again in this 2000 survey, all statistically significant trends are negative. In the family Chaetodontidae numbers of Chaetodon trifasciatus and C. kleinii have declined since 1996 then stabilised after 1999 and 1998 respecitively. Declines at 2000 in the family Siganidae are largely due to Siganus doliatus. The genera Chrysiptera (C. rollandi and C. talboti) and Pomacentrus (P.moluccensis, P. amboinensis and P. brachialis ) have both declined from the 1996 survey. While Chrysiptera is not recovering Pomacentrus appears to have stabilised at 2000. Neopomacentrus azysron and Chromis ternatensis have declined from peaks in 1995 and 1997 respectively.

Macgillivray (No. 14-114) is a middle shelf planar reef with an area of .5 sq.km. Last surveyed July 2002.







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