Coral Reef Diagnostics

Egypt Red Sea - Gazella Reef (Wadi Lahami)

Reef Check Foundation
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05
Photo: Anderson Mayfield/Coral Reef Diagnostics
Country
Survey date(s)
2024-09-22
Coordinates
24.1877, 35.4386
This site is in the vicinity of a land-based point.
Coral cover
17%
Manual point count (214 photos) · other methods below
Observations
Heat stress
Today’s heat load
16 Sep 2026 · Alert Level 2
5-year thermal stress load
5-year mean max. degree heating weeks (DHW)
2021–2025
NOAA Coral Reef Watch — Egypt 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 infoEgypt (NOAA CRW virtual station) · Northern and Central Red Sea ecoregion mean=12.2°C-heating weeks
Photographs
4
Site summary
Read this summary in:

Gazella Reef is a well-built ridge-and-slope system - corymbose and staghorn Acropora, cauliflower pocilloporids in pink and lavender, with a lionfish sheltering in the shadows - and carries the clearest side-by-side bleaching evidence in the Wadi Lahami set: two touching Pocillopora colonies of identical growth form, one bleached uniform cream-white and one holding full pink-lavender pigment. Published cover was 17% with 53.8% of coral tissue bleached, the lowest bleaching figure of the four Wadi Lahami sites here but still more than half the reef.

Max. depth dived
15.8 m
dive-log maximum
Water temp. during survey
31.0°C
+3.6°C vs the 2024 mean sea temperature (27.4°C)
Bottom time
64 min
in at 09:32

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

Four other CRD dive sites within 5 km shown in orange — click a marker to open its page.

Photo credit & attribution

Site description

Setting

The reef is a ridge-and-slope system: a coral-covered ridge running along the drop, canyon-like gaps between coral massifs, and a face descending into deep blue with sand at its foot (e.g., Image 3, Image 4).

General benthic features

It is more built than Shabrour-north — corymbose and staghorn Acropora, cauliflower pocilloporids in pink, rose, and lavender, encrusting, and foliose plates, faviids, and small massives packed along the ridge, with anthias and chromis pouring over it and a lionfish in the shadows (e.g., Image 1, Image 2).

Coral cover

Coral cover is 16.5% ± 12.2 across 214 photographs, quoted verbatim from Mayfield, A.B. (2025) Environments 12:248 — Red Sea 2023-24 bleaching; CoralNet point annotation, Appendix A — a manual, diver-annotated CoralNet point count from Anderson's own published work, not a computer vision output and not recomputed here.

Stressors

The site record reports 53.8% of coral tissue bleached at about 21.9°C-weeks DHW, the lowest bleaching figure of the four Wadi Lahami sites here but still more than half the tissue on the reef. The frame Anderson captioned "dead vs. alive" is a deliberate side-by-side: his own finger points at a bleached cream-white Pocillopora sitting directly beside a fully pigmented pink-lavender Pocillopora of the same growth form, on the same patch of rock. Two colonies, one frame, one comparison.

Comparisons with other data

No independent survey was made at this exact site; the nearest ones are listed in the table below.

Dive record

The second dive of 22 September 2024 with Red Sea Diving Safari, on the reef complex south of Shabrour.

Other notes

See flags.

CV model comparison

Computer vision on this site's own photographs gives In-house DINOv3 point classifier 41% — reported alongside rather than merged, because as of September 2026 no computer-vision method estimates coral cover accurately on new images.
Headline is the reference value; every other row is listed beside it for comparison and none is averaged in.
More infoThe reference row is this dive site's own published value (Mayfield 2025, Appendix A, 214 photos); the other rows are AREA-level (Wadi Lahami) comparisons, not run on this site's frames. ⚠ The comparison rows are REGIONS, not dive sites: the paper's main tables report cover by region, and this site's own value comes from its Appendix A. ⚠ The manual column and the CV columns are on DIFFERENT FRAME SETS: the published cover spans 674–1,180 frames, the CV arms ran on the 30- and 129-frame hand-scored reference subsets. CoralNet is n/a by design: the reference set IS the hand-scored set. DINOv3 is restricted to frames it never saw. CoralNet automated point classifier: n/a — the reference set IS the hand-scored set; these frames carry no independent CoralNet robot label to compare against CoralSCOP (SAM-based mask-sum), unedited photos: pending — CoralSCOP run: 370/747 images scored at build time CoralSCOP (SAM-based mask-sum), edited photos: pending — CoralSCOP run: 370/747 images scored at build time
MethodHard-coral cover (%)
Manual (published)16.5
In-house DINOv340.6
Claude28.0

Independent surveys nearby

Hard coral cover over time — this site and every independent station within 5 km. Programs are shown separately because they use different methods at different stations; the lines are not one comparable series.
0%15%30%45%60%200920162024Reef Check 2009: 30%Reef Check 2009: 56%Reef Check 2012: 30%Reef Check 2012: 45%Reef Check 2018: 46%Reef Check 2018: 52%Reef Check 2023: 41%Reef Check 2023: 44%Dr. Coral (CRD) 2024: 17%Year-averaged across all programs: no detectable trend (-0.83 pp per year, not separable from zero; 5 years)
Reef Check Dr. Coral (CRD)Year-average (no detectable trend)

Within 5 km, 2 independent survey stations recorded hard coral cover in 16 surveys between 2009 and 2023. Of the 2 stations surveyed in more than one year, 1 declined and 1 increased between their first and latest surveys. The longest record, Wadi Lahami House Reef 1 (Reef Check, 3.20 km away), went from 30% in 2009 to 41% in 2023. Surveys since 2021 average 43% (range 41–44%, n=2). This site's own estimate (17%) sits 24.7 points below the recent range (41–44%); 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 range is shown. Station names are not dive-site names.

Independent survey data near this site
AgencySite / locationDateHard coral cover (%)DistanceLink
Reef CheckWadi Lahami House Reef 12009–202330–46% (8 surveys)3.20 km—
Reef CheckWadi Lahami House Reef 22009–202344–56% (8 surveys)3.23 km—

Data & links

All images from Coral Reef Diagnostics. Data are from Coral Reef Diagnostics and the organizations named in the data-sources table above.

© Coral Reef Diagnostics.