Khaled bin Sultan Living Oceans Foundation — Global Reef Expedition

Fiji - Matuku (FJMT11)

Part of the regional summaries: Fiji - Matuku, Fiji - Moala Group (Moala / Totoya / Matuku), and Fiji - Lau

Outlier score: 4.44/5 (Matuku, n = 9 corals with an outlier score). The share of those corals whose molecular stress profile was an outlier, rescaled to 0-5 (5 = no outliers); an island-level measure (Mayfield et al. 2017), not a Coral Health Index.

Country

Fiji

Survey date(s)

2013-06-06

Coordinates

-19.1585, 179.7304

Coral cover

30%

± 4.7% SE, n = 4 transects · Benthic transects+photo-quadrats

Observations

predationrecent mortality

Heat stress

Most recent heat load record

25.8°C 0.0°C-weeks

26 Oct 2026 · No heat stress

5-year thermal stress load

5-year mean max. degree heating weeks (DHW)

8.9°C-weeksⁱ

2021–2025

NOAA Coral Reef Watch — Fiji virtual station

i 5-year mean max. DHW is the mean of the annual maximum DHWs over the five complete years named above, not conditions today.

More info

Fiji (NOAA CRW virtual station)

Site summary

Read this summary in:

Silty fore-reef sand flats at the base of Matuku's steep slope, with large branching acroporids and plating corals, at 30% cover. Coral-eating Drupella snails on several colonies may explain recent mortality scars, and a Reef Check station 0.53 km away recorded 56% in 1999 (a different method and site, so not a true trend). Surveyed on the Living Oceans Foundation's Global Reef Expedition.

Max. depth dived

18.3 m

dive-log maximum

Water temp. during survey

27.0°Cⁱⁱ
CTD-cast midpoint of 27.0–27.1°C

-0.2°C vs the 2013 mean sea temperature (27.2°C)

ii Station CTD-cast midpoint (LOF station records), not a dive reading: midpoint of the station's maximum and minimum CTD water temperature (Living Oceans Foundation Fiji station records); range 26.96–27.11°C.

Bottom time

58 min

in at 12:06

Three independent survey stations shown with the program’s logo — click one to see how far it is from this site.

Two other CRD dive sites with their own pages within 5 km shown in orange — click a marker to open its page.

Site description

Setting

The expedition's site notes place FJMT11 on fore-reef sand flats at the base of the steep reef slope. The same notes record poor visibility, with a fair amount of suspended sediment.

General benthic features

The team's notes record plating Pachyseris and Echinopora colonies as common at the base of the slope.

Coral cover

Reference: Khaled bin Sultan Living Oceans Foundation, Global Reef Expedition (in situ transect)
Coral cover 30% (the expedition's in situ transects).
Transect mean 30 ± 4.7% SE (n = 4 transects; Living Oceans Foundation per-transect benthic data); the headline above is this all-transect mean.

Stressors

The team's notes record large branching acroporids with some recent mortality as common. Drupella snails were found on several colonies which could account for some recent mortality scars on the acroporids. The Living Oceans Foundation transects here recorded 1.5% cyanobacteria and no recently dead coral on the transect lines.

Comparisons with other data

Apart from the Living Oceans Foundation survey shown here, we found no other surveys at this site as of 2026. Within 5 km, three Reef Check stations recorded station-year means of 39–56% hard coral cover in 1999; the nearest, Reef Check at Maccadame Reef, 0.53 km away, read 56% in 1999.

Dive record

FJMT11 (Matuku, Lau Archipelago): surveyed 6 Jun 2013 during the Khaled bin Sultan Living Oceans Foundation Global Reef Expedition.

No underwater photographs from this station are on file.

Independent surveys nearby

Within 5 km, 3 independent survey stations recorded hard coral cover in 1999. The most recent nearby survey is from 1999, so these values predate recent heat stress. This site's own estimate (30%) sits 9 points below the range of these station-year means up to 2 km away (39–56%); the methods differ, so the comparison is context, not a like-for-like test.

Collected by other programs using different methods (Reef Check uses point-intercept transects), so these are context for the figures above, not a like-for-like comparison. Where a station was surveyed more than once, the cell shows either the range of its values or, as a single value, the mean of surveys made in one year. Station names are not dive-site names.

Independent survey data near this site
Agency	Site / location	Date	Hard coral cover (%)	Distance
Reef Check	Maccadame Reef	1999	56%, mean of 2 surveys (2 m and 10 m)	0.53 km
Reef Check	North of Arua	1999	39%	0.88 km
Reef Check	Dabu Passage	1999	51%	4.23 km

Data & links

Data are from the Khaled bin Sultan Living Oceans Foundation Global Reef Expedition, Coral Reef Diagnostics, and the organizations named in the data sources above.