Table of Contents

• Coverage
• Dataset Description
  • Methods & Sampling
  • Data Processing Description
• Data Files
• Supplemental Files
• Parameters
• Instruments
• Deployments
• Project Information
• Funding

This dataset includes all photographs taken of individual coral colonies during and after the 2015 bleaching event on Ofu, American Samoa. Photographs were taken at four time points spanning the bleaching events: April 2015 (during bleaching), August 2015, December 2015, and April 2016. Species photographed include Acroproa gemmifera, Acropora hyacinthus and Pocillopora damicornis. 

Tabular data served through this dataset landing page includes a column of links to each individual image.  All images and a list of all image names, collection date, time, and image links can be downloaded from the "Data Files" section of this page.

Photographs were taken at four time points spanning the bleaching events: April 2015 (during bleaching), August 2015, December 2015, and April 2016. Species photographed include Acroproa gemmifera, Acropora hyacinthus and Pocillopora damicornis. 

BCO-DMO data manager processing notes:
* Metadata (tagID, lat, lon) data was submitted separately from the image files. 
* Indexed all images and attached inventory as a supplemental document.
* Joined the image metadata (tagID, lat, lon) to the imagenames, at behest of data submitter, only the images that had metadata are included in the tabular dataset served from this page. The full image inventory (including ones without tags and locations) is included in the zip download of all images, and the image_inventory.csv file (supplemental document).

Description from NSF award abstract:
The strongest coral bleaching event in nearly 20 years began in American Samoa in January 2015. Coral bleaching occurs when ocean water temperatures exceed a coral's normal heat tolerance. But bleaching events usually show an unexplained pattern - colonies next to one another can show very different levels of bleaching - from pure white to the normal tan color of a healthy coral. The investigators have observed this pattern among 280 corals on reefs in American Samoa that have been studied for years. This system will be used to test four major hypotheses about what causes some corals to bleach and some not: differences in 1) species, 2) the temperature the corals experienced, 3) the symbiont they harbor, and 4) the genotype of the coral host. In addition, the investigators will return to American Samoa at regular intervals to measure the rate of recovery of each coral colony and conduct the same tests as above for recovery rate. The stark-white reefscapes left behind by bleaching events are one of the most common signals of increased ocean warming. This work will take advantage of years of prior study and the advent of a coral bleaching event to understand the rules for survival on reefs.

The reefs of American Samoa began showing a major bleaching event starting in January 2015, including 62 corals that have been intensively studied for coral thermal resistance, field temperatures, and symbiont type. In April 2015 the investigators monitored bleaching status of these and additional corals, totaling 280 corals from four species, and uncovered marked variation in bleaching extent within and between species and within and between reef regions. The team will test the relative importance of microclimate to bleaching state by examining records of approximately 50 temperature loggers in place since before the bleaching event. They will test the influence of symbiont type and host gene expression profiles by examining samples of 60 colonies taken at four time points after bleaching. The investigators will also examine the full suite of 280 corals for genetic variation to estimate the relationship between bleaching state, recovery rate and genetic polymorphism. These data will be used to test micro-climate, symbiont, and coral genetics as determinants of bleaching and bleaching recovery. Because the investigators have samples from these 280 colonies before bleaching mortality, this study will provide the first estimate for the evolutionary impact of a bleaching event on coral populations.