SVG - Mayreau Shipwreck

Setting

The wreck sits just off Mayreau in the Tobago Cays/Grenadines, a short boat ride from the Mayreau Gardens patch reef and the volcanic CO2 seep Anderson's team had spent the week sampling for the Enochs et al. 2020 acidification study -- this final-day dive, 1 Oct at dusk (17:29-17:53, ~11 m), was the trip's one deliberately recreational stop.

General benthic features

The photos show unmistakable wreck architecture: straight metal girders and hull plating draped in encrusting red sponge and coralline algae, a mooring line, dark swim-through cavities used as dens, and a curved, growth-crusted hull section breaking the water-column silhouette against the afternoon sun (e.g., Image 1).

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Colonization is present but sparse -- small encrusting Siderastrea and Porites astreoides patches, a few brain coral-like colonies (cf. Pseudodiploria), sea fans and whip gorgonians rising off the structure, generally pale-toned but not obviously bleached or diseased (e.g., Image 2, Image 5).

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Coral cover

• Reference: Claude CV point count (this site's photos)
• Coral cover: 4.9% — a blind Claude computer-vision point count of 28 of Anderson's edited photographs (20 points per photo; water, fish, and obstructions excluded). The median is 0%; on a wreck, low coral cover is expected. 18 of the 28 photos show no coral at all (hull, sand, water); the value comes from colonies on the hull.

Stressors

No bleaching, disease, or corallivores observed.

Fish and other fauna

The standout subject, by far, is Caribbean spiny lobster (Panulirus argus): a remarkable density of them, including a mother-and-young pair, tucked into nearly every crevice and porthole (e.g., Image 3, Image 4).

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Small reef fish round things out -- sergeant majors, grunts, a school of blue chromis or creole wrasse streaming through one dark opening.

Comparisons with other data

The 2005-2007 Reef Check numbers from Petit Bateau (13.8% in 2005 and 18.8% in 2007 - the 22 and 30 in the source are hard coral POINT COUNTS out of 160 substrate points, not percentages), 3.2 km away, are the closest regional coral-cover context available, but say nothing about the wreck itself, which has never been surveyed.

Other notes

Tentatively identified as the Puruni, a 1918 wreck reported at ~40 ft off Mayreau near Mayreau Gardens -- the depth and location line up closely, but no nameplate or hull marking is visible in any frame, so treat the identity as likely, not confirmed.