The Rocks (FKNMS)

Setting

The Rocks is an Upper Keys inshore patch reef, one of the four NOAA/FKNMS research sites with colonies tagged and genotyped by the NOAA AOML team in July 2017, which Anderson resampled in 2019 for the work published as Mayfield et al. 2021–2023.

General benthic features

The photographs show a working monitoring station rather than a scenic reef. Scattered mounding Orbicella faveolata and Montastraea cavernosa heads and Siderastrea siderea domes sit on low limestone hardground, and the space between them, and much of the rock itself, is blanketed in thick red and brown fleshy macroalgae — in places the algae fills the foreground completely and the reef is only inferable from the fish above it.

Coral cover

• Coral cover: 9.3% (August 2016), from the NOAA NCRMP and NOAA AOML photo-transect survey of this reef published by Manzello et al. (2019, Global Change Biology) — 40 frames on two 10 m transects, point-counted. Macroalgae and turf covered over 80% of the benthos.

Stressors

Tagged study colonies are conspicuous: several carry rows of circular biopsy core holes, one colony, photographed with a fluorescent hammer for scale, is so overgrown by turf and fleshy macroalgae that living tissue survives only as a patch on the crest, and a temperature or light logger sits fouled on rebar stakes among the corals. Two condition observations are Anderson's own field calls. A large Siderastrea siderea dome, recorded as dying (October 2019), has an active tissue-loss margin: a band of clean white, freshly exposed skeleton separates its live tissue from a large turf- and sediment-covered dead patch (cause unclear). Tagged colony 3975 was pale cream all over in August 2019 (Anderson noted it as paling), when the dive-average water temperature was 31.6°C. A second knobby colony photographed on the same 21 August 2019 dive was paling too, its upper part cream-white over tan tissue: the same paling (partial bleaching) event (photo not shown). No corallivores were evident.

Fish and other fauna

Fish are abundant despite all this: a school of Atlantic spadefish over dense French grunts, sergeant majors, and three Caribbean spiny lobsters under an algae-covered ledge.

Comparisons with other data

Apart from the NOAA survey shown here, we found no other surveys at this site as of 2026. Within 5 km, twelve independent stations (NOAA NCRMP, NOAA NCRMP Florida, and Reef Check) recorded station-year means of 0.0–37% hard coral cover between 1997 and 2024; the nearest, NOAA NCRMP at FLK-436, 0.46 km away, read 10% in 2016.

Dive record

Anderson logged four dives here in 2019 (10 July, 21 August, 9 October, 4 December; 4.3 m maximum, 24.5–31.6°C (dive averages) — the August water was over 31°C).