Help Us Track Coral Bleaching in Your Community

Coral bleaching is a distress signal from our oceans. When corals lose their symbiotic algae—zooxanthellae—they turn pale or white and lose their primary source of nutrients. Though bleached corals can survive short periods, prolonged stress increases their risk of disease and death. Today, the world is experiencing the most severe coral bleaching event in recorded history: between 2023 and 2025, approximately 84% of the world’s reefs have been impacted, receiving urgent attention from marine scientists worldwide.

Yet, scientists alone can’t observe every reef frequently or at fine scale. That’s where you come in. Citizen and community science programs—like Reef Check and BleachWatch—have shown that trained volunteers can contribute high-quality, real-time data that improves reef monitoring, situational awareness, and conservation effectiveness.

By using the form below to share a timestamped photo and environmental details of coral near you—temperature, depth, bleaching severity, reef zone—you’re helping build an invaluable, accessible record. This collective data helps scientists detect trends, validate models, and target conservation efforts where they matter most. Together, we can make a difference for coral reefs—one observation at a time.

What Does Bleaching Look Like?

Coral bleaching can usually be recognized by a uniform paling or complete whitening of the coral tissue, caused when corals expel the symbiotic algae (zooxanthellae) they rely on for food. Healthy corals display vibrant browns, greens, and other colors, but when stressed by heat or other environmental factors, they appear ghostly white or pastel. This differs from coral disease, which typically shows up as distinct, irregular patches or bands of discoloration, tissue loss, or abnormal growths. While bleaching affects the entire colony evenly, disease is more localized—such as a spreading dark band, a white skeleton margin, or scattered lesions. Spotting this difference is important: bleaching reflects stress that may be reversible if conditions improve, while disease indicates an active infection or tissue loss that often requires targeted monitoring and response.

Distinguishing Between Bleaching and Disease

Report Coral Bleaching

Tap the map to set location, add details, and upload a photo.

Observer

Name *

Email (optional)

We may contact you if clarification is needed.

Observer Role / Experience * Select one Not formally trained Ecological monitoring certified Advanced ecological monitoring certified Marine scientist

I consent to my data and photo being used for research and public reporting *

When & Conditions

Date & Time *

Auto-filled from photo EXIF if available.

Weather — Select — Clear / Sunny Partly Cloudy Overcast Rainy Windy

Water Visibility — Select — Low (<5 m) Moderate (5–10 m) High (>10 m)

Location

Use my location

Lat: — · Lng: —

Latitude *

Longitude *

Reef Zone — Select — Fore Reef Reef Crest Back Reef / Lagoon Reef Flat Slope

Tap the map to set the pin, or edit the numeric latitude/longitude fields directly.

Water

Water Temp — Surface (°C)

Water Temp — At Depth (°C)

Depth (m) *

Bleaching & Mortality

Bleaching observed? * — Select — No Yes

Bleaching Severity Code

% unknown

0 — No bleaching

1 — Mild (1–10% bleaching)

2 — Moderate (11–50% bleached)

3 — Severe (>50% bleached)

Percent bleached (as % of coral cover or # colonies; enter N/A if not measured)

How did you calculate the percent bleached? — Select — Percent of total corals surveyed Percent of total coral cover across the reef site visited Total number of colonies bleached within area surveyed Other method N/A

Coral Mortality Code

% unknown

0 — No mortality

1 — Mild (1–10% mortality)

2 — Moderate (11–50% mortality)

3 — Severe (>50% mortality)

Percent mortality (recent mortality only; enter N/A if not measured)

Survey type

Photo

Upload Photo

Use outward-facing camera on mobile when possible. JPG preferred for metadata.

EXIF: —

If EXIF contains GPS or date/time, they will auto-fill.

Notes

Please list anything unusual you noticed at the site

Data Sharing & Contact

Because these data will be included within NOAA Coral Reef Watch’s global coral bleaching observations database, they eventually may be made available to the public. Check this box if you do not agree to have your data publicized.

Data point of contact — Name *

Data point of contact — Email *

If you represent an agency, organization, research laboratory, business, group, etc., list which one

Submit Report Reset

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