St. Maarten - Proselyte Reef
More about this place: Sint Maarten on Wikipedia
More info
Leeward Caribbean Islands (NOAA CRW virtual station)A shallow, low-relief spur of brain and boulder star coral under a soft-coral canopy of sea plumes and fans, with encrusted chain and metal debris among the coral heads. Context (dive-operator and press sources): the reef is named for HMS Proselyte, wrecked here in 1801. A blind Claude computer-vision point count puts coral cover around 7.9%. That is within the 1.9–13% recorded at four independent survey stations within 5 km between 2005 and 2013.
Een ondiepe uitloper met weinig reliëf van hersenkoraal en sterkoraal onder een bladerdak van zachte koralen, zeeveren en zeewaaiers, met begroeide ketting- en metaalresten tussen de koraalkoppen. Context (bronnen van duikoperators en de pers): het rif is genoemd naar HMS Proselyte, die hier in 1801 verging. Een blinde puntentelling met Claude-computervisie schat de koraalbedekking op ongeveer 7.9%. Dat valt binnen de 1.9–13% die tussen 2005 en 2013 is gemeten op vier onafhankelijke onderzoeksstations binnen 5 km.
AI translation of this summary; the English is authoritative.
Four independent survey stations shown with the program’s logo — click one to see how far it is from this site.
One other CRD dive site with its own page within 5 km shown in orange — click a marker to open its page.
These are unedited originals; edited versions will replace them.
15 of the 48 photographs on this page are shown beside the text that discusses them under "Site description" below.
Site description
Setting
Proselyte Reef takes its name from HMS Proselyte, a Royal Navy frigate wrecked here in 1801, and pieces of encrusted chain and metal debris still turn up among the coral heads as a reminder of that history (e.g., Image 48).
The site itself is a shallow, low-relief spur of coral rock and rubble, its surface knit together by big brain corals — grooved and smooth-faced colonies alike — and sturdy boulder star corals, with mustard hill coral filling in the gaps (e.g., Image 10, Image 18, Image 22, Image 31, Image 39, Image 47).
It's an easy, scenic introduction to St. Maarten's reef life — equal parts natural history and maritime history.
General benthic features
A soft-coral canopy of sea plumes, sea rods, and sea fans sways over much of the reef, punctuated by barrel sponges and patches of vivid orange and red encrusting sponge (e.g., Image 3, Image 8, Image 16, Image 20, Image 44).
Coral cover
- Reference: Claude CV point count (this site's photos)
- Coral cover: 7.9% — a blind Claude computer-vision point count of 114 of Anderson's unedited photographs (20 points per photo; water, fish, and obstructions excluded). Other computer-vision methods are listed in the method table.
Stressors
No corallivores were evident.
Fish and other fauna
Divers can expect schooling chub and jacks overhead, sergeant majors and wrasses working the reef face, the occasional Caribbean reef shark passing in the blue, and spiny lobsters tucked into the many ledges and crevices (e.g., Image 12, Image 27, Image 37).
Comparisons with other data
XL Catlin Seaview Survey surveyed this site (transect 25035) in 2013, 0.06 km from the pin. Within 5 km, four independent stations (Reef Check and XL Catlin Seaview Survey) recorded station-year means of 1.9–13% hard coral cover between 2005 and 2013; the nearest, XL Catlin Seaview Survey at transect 25035, 0.06 km away, read 1.9% in 2013.
CV model comparison
More info
A few colony-focused photos raise the mean; the median is the typical photo. No computer-vision method yet estimates coral cover accurately on new images, so treat this as indicative rather than a measurement; it is revised as the methods improve.More info
DINOv3 and CoralSCOP were run on the same photos and are listed for comparison. No diver transect exists for this trip, so agreement between the rows is not accuracy, and no computer-vision method yet estimates coral cover accurately on new images; treat every row as indicative.| Method | Hard coral cover (%) | Photos (n) ± SE |
|---|---|---|
| In-house DINOv3 | 18.4 | n = 114 · SE 0.8 |
| CoralSCOP unedited | 23.6 | n = 114 · SE 1.4 |
| Claude | 7.9 | n = 114 · SE 1.2 |
| Reef Check 2006 (same site) | 10.0 |
The two computer-vision methods agree within 5.2 pp (18.4–23.6%) and read 10.5–15.7 pp above Claude's blind point count (7.9%); the headline is Claude's blind point count because no transect or manual count exists here.
See a more detailed, stand-alone version of this table.
Independent surveys nearby
| Agency / program | Year(s) | Stations / distance | Link |
|---|---|---|---|
| Reef Check | 2005–2006 | 3 stations, 0.11–1.83 km | Records ↓ |
| XL Catlin Seaview Survey | 2013 | 1 station, 0.06 km | Records ↓ |
Coral Reef DiagnosticsYear-average (illustrative only, programs differ)Within 5 km, 4 independent survey stations recorded hard coral cover in 4 surveys between 2005 and 2013. The most recent nearby survey is from 2013, so these values predate recent heat stress. This site's own estimate (7.9%) sits within the range of these station-year means (1.9–13%); 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; the XL Catlin Seaview Survey uses photo-transects with automated image annotation), 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 |
|---|---|---|---|---|---|
| Reef Check | Mike's Maze 2 | 2005 | 13% | 1.76 km | — |
| Reef Check | Proselyte Reef | 2005 | 6.3% | 1.83 km | — |
| Reef Check | Mike's Maze 1 | 2006 | 10% | 0.11 km | — |
| XL Catlin Seaview Survey | transect 25035 | 2013 | 1.9% | 0.06 km | doi:10.14264/uql.2019.930 |
Data & links
All images from Coral Reef Diagnostics. Data are from Coral Reef Diagnostics and the organizations named in the data sources above.
© Coral Reef Diagnostics.