Coral Reef Diagnostics

Saudi Red Sea - Coral Gardens (Jeddah)

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05
Photo: Anderson Mayfield/Coral Reef Diagnostics
Survey date(s)
2024-08-10
2024-08-17
Coordinates
21.7820, 38.8337
Approximate position.
Coral cover
28%
Published point count (Mayfield 2025; CoralNet-assisted, 300 photos) · details below
Coral bleached
43%
of coral tissue · Mayfield (2025), Environments 12:248
Observations
Heat stress
Most recent heat load record
26 Oct 2026 · Alert Level 2
5-year thermal stress load
5-year mean max. degree heating weeks (DHW)
2021–2025
NOAA Coral Reef Watch — Al Madinah and Makkah 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 infoAl Madinah and Makkah (NOAA CRW virtual station)
Photographs
308
23 shown on this page
Site summary
Read this summary in:

Coral Gardens lives up to its name — a reef built on giant, several-meters-wide massive Porites mounds and tall pinnacles rising almost to the surface, layered with staghorn and corymbose Acropora and rose-colored pocilloporids. Across two August 2024 visits a week apart, cover held steady at 27-29% while the bleached fraction of coral tissue climbed from 41% to 45% as accumulated heat stress rose, with the reef's largest defining corals — the giant Porites mounds — showing near-universal paling.

Water temp. during survey
32.5°Cii
+3.2°C vs the 2024 mean sea temperature (29.3°C)
ii Mean of Anderson's in-situ dive temperatures at depth on 2 dives here: 32°C on 10 August 2024 and 33°C on 17 August 2024 (Mayfield 2025, Environments 12:248, Appendix A).
More infoNote: NOAA's regional station series averages 1.8°C warmer than the satellite pixel nearest this site (1.2 km away), which is used here instead.

One other CRD dive site with its own page within 5 km shown in orange — click a marker to open its page.

10 of the 23 photographs on this page are shown beside the text that discusses them under "Site description" below.

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Photo credit & attribution

Site description

General benthic features

The reef is built on giants. Its defining structures are enormous knobby and columnar Porites mounds — one frame is filled edge to edge by a single colony several meters across and several meters tall, standing free on sand with anthias streaming past — and tall pinnacles that rise almost to the surface, their flanks holding clouds of small fish (e.g., Image 5, Image 6).

Between and over them sit corymbose and staghorn Acropora in tan and gold, dusty-rose and salmon pocilloporids, green foliose plates, small domed massives, and encrusting plates (e.g., Image 1, Image 8, Image 9); giant clams (e.g., Image 21, Image 22) and a blue-spotted ribbontail ray (Image 23) sit in the pavement.

Coral cover

Stressors

Nearly all of the big Porites mounds are pale (e.g., Image 7), and one large massive colony carries old partial mortality: its upper surface is gray, turf-covered dead skeleton above a basal band of living brown tissue (e.g., Image 3).

Anderson's field notes for these dives, which record paling Porites, mild bleaching, struggling corals, and a bleached Pocillopora verrucosa, describe exactly what the frames show.

Comparisons with other data

Apart from our own published survey shown here, we found no other surveys at this site as of 2026. If you would like to share yours, please email us.

Dive record

Two dives a week apart in August 2024 with Al-Haddad SCUBA, on a Jeddah reef that lives up to its name.

Survey summary

Coral Gardens: surveyed twice in August 2024 (10 and 17 August) (CoralNet point counts; Mayfield 2025, Environments 12:248). Surveyed in partnership with Al-Haddad SCUBA.

CV model comparison

Computer-vision estimates from this site's own photographs are listed in the comparison table below, alongside the headline rather than merged into it.
Headline is the reference value; every other row is listed beside it for comparison and none is averaged in.
More infoThe reference is this dive site's own published CoralNet point count by the author (Mayfield 2025, Environments 12:248, Appendix A; most frames annotated by CoralNet's AI, trained and checked by the author). The computer-vision rows are this site's own values: Claude is a blind point count of all of the site's edited photographs, DINOv3 ran on the site's benchmark frames (the photographs the author annotated point by point), and CoralSCOP is the site's finished survey of its edited photographs. They are on different frame sets from the published count, a row under 30 frames is indicative only, and no computer-vision method yet estimates coral cover accurately on new images.
MethodHard coral cover (%)Photos (n) ± SE
Published point count (CoralNet-assisted)27.6
In-house DINOv344.5n = 156
CoralSCOP edited29.2n = 254
Claude (edited photos)25.5n = 271 · SE 1.0

The three computer-vision methods disagree by 19.0 pp (25.5–44.5%) and read on both sides of the published point count (27.6%); the headline is the published point count because it is the site's published value (CoralNet-assisted: most frames were annotated by CoralNet's AI, trained and checked by the author).

Dive history

Coral bleached: computer-vision (CoralNet) estimate from the survey images, per dive, as published in Mayfield (2025, Environments 12:248), Supplementary File S1.

DateTime inMax depth (m)Bottom time (min)Coral bleached (%)
2024-08-10———41.4
2024-08-17———45.4

Data & links

All images from Coral Reef Diagnostics. Data are from Coral Reef Diagnostics.

© Coral Reef Diagnostics.