Decadal-scale time series highlight the role of chronic disturbances in driving ecosystem collapse in the Anthropocene

These data support a publication in the Journal Ecology that describes 37 years of change on the coral reefs of St. John, US Virgin Islands. In this paper, four decades of surveys from two coral reefs (9 and 14 m depth) off St. John, US Virgin Islands, are used to quantify the associations of acute and chronic events with the changes in benthic community structure. These reefs profoundly changed over 36 years, with coral death altering species assemblages to depress abundances of the ecologically important coral Orbicella spp. and elevating the coverage of macroalgae and crustose coralline algae/turf/bare space (CTB). Linear mixed models revealed the prominent role of chronic variation in temperature in accounting for changes in coverage of corals, macroalgae, and CTB, with rising temperature associated with increases in coral cover on the deep reef, and declines on the shallow reef. Hurricanes were also associated with declines in coral cover on the shallow reef, and increases on the d..., The study began in December 1987 to evaluate the effects of coral bleaching. Three, 10-m long, permanently marked transects were established at 14-m depth at the Tektite reef, and at 9-m depth at Yawzi Point. These reefs were selected because of their high percentage cover of Orbicella spp. and ease of access from a field station with small boats.
Each transect was sampled using 10 contiguous photoquadrats (1 × 1 m), recorded annually between May and December beginning in December 1987 and ending in July 2022. The reefs were sampled twice each year in 1988, 1989, and 2017 to evaluate the effects of hurricanes, and initially were recorded using color slide film, and from 2001, digitally. A strobe was used with all cameras, each image contained a scale bar, and slides were digitized (4000 dpi) for analysis. Images were analyzed using CPCe or CoralNET software, with 200 randomly-located points image-1 that were manually annotated to resolve coral (scleractinians and Millepora), macroalgae,..., , # Data from: Decadal-scale time series highlight the role of chronic disturbances in driving ecosystem collapse in the Anthropocene

[https://doi.org/10.5061/dryad.x0k6djht1](https://doi.org/10.5061/dryad.x0k6djht1)

The data managed here describe how coral community structure at two sites (Yawzi Point and Tektite) have changed over 37 years based on mostly annual samplings. The data originated form 1 x 1 m quadrats recorded photographically at fixed positions on the reef.  Ten quadrats are recorded along each of three transect lines, each ~ 10 m long and 5 m apart at each site. Images are analyzed using a grid of 200 randomly-located dots and analyses are completed with (a) functional group resolution, and (b) by coral genus

## Description of the data and file structure

**File 1: Yawzi_Point_Functional_Groups_1987_2022**

This files contains functional group data for Yawzi Point:

These data support Figures 1A and 3A, and describe how the community structure at Yawzi Point has change...