Part of the regional summaries: Australia (GBR) - Far North: Blue stations (Habitat Protection Zone reefs) and Australia (GBR)
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Far Northern GBR (NOAA CRW virtual station)A Jewell Reef forereef sharply zoned by depth: shallow spurs at 5-8 m carry 40-50% live cover of branching corals with strong recruitment, while a few pitiful-looking needle corals remain at 25 m and bleached needle coral turned up on a 20.5 m transect. Visibility reached 30-40 m and a cushion star was spotted at 20 m. Surveyed on the Living Oceans Foundation's Global Reef Expedition.
One independent survey station shown with the program’s logo — click one to see how far it is from this site.
Five other CRD dive sites within 5 km shown in orange — click a marker to open its page.
🗺 Detailed map of the Global Reef Expedition dive sites, Jewell, Hilder, and Eyrie Reefs, northern Great Barrier Reef (Khaled bin Sultan Living Oceans Foundation; opens in a new window)
6 of the 30 photographs on this page are shown beside the text that discusses them under "Site description" below.
Site description
Setting
Visibility ranged out to 30-40 m at times despite a steady 1-knot current. This site is in a Habitat Protection (Blue) Zone, where line fishing is permitted.
General benthic features
The real coral action was shallower: at 5-8 m, certain reef "spurs" carried 40-50% live cover, dominated by pocilloporids and acroporids with a scattering of soft corals and Platygyra, and crustose coralline algae patches hosting strong coral recruitment (e.g., Image 1, Image 2, Image 3, Image 4, Image 5).
His transects at 10-20.5 m ran from under 5% live coral on the low-relief 20.5 m line to 30-40% (with 20-30% soft coral) at 10 m, over turf-covered rubble and large sand patches. Porites was the most common coral genus on this station's transects (6.0% of the benthos), followed by Favia, Pavona, and Pocillopora (3.0% each) and Goniastrea and Montipora (2.0% each); bare substrate covered 41%, the largest non-coral class. Among the algal classes on this station's transects, crustose coralline algae (12%) led, followed by turf (10%) and sediment-laden turf (3.0%).
Coral cover
- Reference: Khaled bin Sultan Living Oceans Foundation, Global Reef Expedition (in situ transect)
- The expedition's point-count transect at this station recorded 20% live coral cover.
- One transect was scored at this station (20%; n = 1, so no SE; Living Oceans Foundation per-transect benthic data); it is the expedition's station value printed above.
Stressors
His notes record bleached Seriatopora hystrix on his first transect (20.5 m) and a few "pitiful looking" seriatoporids at 25 m, where living coral had largely given out.
Fish and other fauna
One cushion star (Culcita) was logged at 20 m, with feeding scars not visible on the colonies around it (e.g., Image 27).
Comparisons with other data
No other surveys have been conducted at this site to date. Within 5 km, one independent station, AIMS manta tow at HILDER REEF, 4.51 km away, read 5.5–40% between 1994 and 2023.
Dive record
Jewell Reef's first dive on 12 September 2014 took Anderson down a well-defined forereef slope (dive-log maximum 21.4 m) that his notes follow to about 25 m, where a hard, coral-built platform survived but living coral had largely given out — just a few "pitiful looking" needle corals (Seriatopora) remained at that depth, and his first transect, at 20.5 m, turned up bleached S. hystrix as well.
CV model comparison
More info
The photo row below is a methods comparison only: it is never averaged with the transect and never used as the headline. It compares site means only: the photos come from the same survey dive as the transect but not from the same points.| Method | Hard-coral cover (%) | Photos (n) ± SE |
|---|---|---|
| Transect (published) | 20.0 | |
| CoralSCOP edited | 32.9 | n = 22 · SE 2.0 |
| Claude (edited photos) | 45.2 | n = 22 · SE 4.1 |
The two computer-vision methods disagree by 12.3 pp (33–45%) and read 12.9–25.2 pp above the in-water transect (20%); the headline is the in-water transect because a diver transect is independent of the photographs.
Independent surveys nearby
LOF Within 5 km, 1 independent survey station recorded hard coral cover in 4 surveys between 1994 and 2023. The one station surveyed in more than one year declined by 0.3 points between its first and latest surveys. The longest record, HILDER REEF (AIMS manta tow, 4.51 km away), went from 39% in 1994 to 39% in 2023. One survey since 2021 recorded 39%. This site's own estimate (20%) is not compared with these surveys: none lies within 2 km.
Collected by other programs using different methods (AIMS manta tow is a towed visual estimate in categorical bins), 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.
| Agency | Site / location | Date | Hard coral cover (%) | Distance | Link |
|---|---|---|---|---|---|
| AIMS manta tow | HILDER REEF | 1994–2023 | 5.5–40% (4 surveys) | 4.51 km | doi:10.25845/5c09b0abf315a |
Data & links
- Download benthic survey data (CSV) ↗
- Download all LOF-GRE data (933 sites) ↗
- Photo portfolio ↗
- Coral Reef Diagnostics country page ↗
All images from Coral Reef Diagnostics. 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.
© Coral Reef Diagnostics.