Reef Health & Bleaching Status

Live coral health assessment across 39 Great Barrier Reef sites

Average Health Score
Moderate Impact

Across all 39 sites

Sites Monitored
39

7 regions covered

Last Updated
10 September 2025

Based on 2024-2025 assessments

Ribbon Reef 10 - Cod Hole
Far Northern
outer reef
Good Condition
Good Condition

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Remote location protected from major bleaching impacts, excellent condition

Lizard Island
Far Northern
outer reef
Good Condition
Good Condition

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Northern outer reefs showed good resilience, deeper sections pristine

Heron Island
Southern Reef
inner reef
Good Condition
Good Condition

Reef Status

Latest Event: 2024 southern bleaching event

Southern location helped avoid worst bleaching, research station monitoring recovery

Escape Reef
Port Douglas
outer reef
Good Condition
Good Condition

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Remote location with minimal impact, excellent coral health

St. Crispin Reef
Port Douglas
mid reef
Good Condition
Good Condition

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Deeper walls protected, best condition in region

Mackay Coral Cay
Port Douglas
outer reef
Good Condition
Good Condition

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Pristine cay location with good water flow, exclusive access maintains reef health

Bait Reef
Whitsundays
outer reef
Good Condition
Good Condition

Reef Status

Latest Event: 2024 mass bleaching

Outer reef position with good currents helped minimize bleaching impact

Agincourt Ribbon Reef
Port Douglas
outer reef
Good Condition
Good Condition

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Strong current flow helping recovery, deeper sections remain healthy

Undine Coral Cay
Port Douglas
outer reef
Good Condition
Good Condition

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Protected location showing good resilience

Tongue Reef
Port Douglas
mid reef
Good Condition
Good Condition

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Good recovery, strong current flow beneficial

Agincourt Ribbon Reef
Port Douglas
outer reef
Good Condition
Good Condition

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Outer reef showing good resilience, deeper waters protecting corals

Milln Reef (Milne Reef)
Cairns
outer reef
Good Condition
Good Condition

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Less visited, Three Sisters bommies in good condition

Hardy Reef - Heart Reef Area
Whitsundays
outer reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Outer reef location helping recovery, pontoon area showing good coral regeneration

Flynn Reef
Cairns
outer reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Popular site showing steady recovery, turtle station active

Saxon Reef
Cairns
outer reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Patch reef structure helped water circulation, moderate recovery

Beaver Reef - Mission Beach
Mission Beach
outer reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Less tourism pressure helping recovery, outer reef position beneficial

South Opal Reef
Port Douglas
outer reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Moderate recovery from 2024, deeper sections healthier

Hardy Reef - Whitsundays
Whitsundays
outer reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Central GBR location affected, pontoon area showing stress, outer edges better

Hastings Reef
Cairns
outer reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Protected inner areas showed more stress, outer edges recovering better

Saxon Reef (Outer Sites)
Cairns
outer reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Magic Wall showing good recovery, shallower areas more affected

Norman Reef
Cairns
outer reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

High tourism area, deeper caves maintaining health

Davies Reef
Townsville
outer reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Varied topography helping recovery, caves providing thermal refuge

Hayman Island Fringing Reefs
Whitsundays
inner reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Blue Pearl Bay maintaining better health, resort conservation efforts helping

Blue Lagoon - Opal Reef
Port Douglas
outer reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Protected lagoon recovering slowly, water flow helping

John Brewer Reef
Townsville
outer reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Central GBR heavily affected, MOUA structures providing artificial reef habitat

Border Island - Whitsundays
Whitsundays
inner reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Protected location helped minimize damage, showing steady recovery

Moore Reef
Cairns
outer reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Heavy tourism impact combined with bleaching, pontoon areas most affected

Lodestone Reef
Townsville
outer reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Significant bleaching in shallow areas, deeper sections maintaining better health

Hook Island - Whitsundays
Whitsundays
inner reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Inner reef location vulnerable, protected bays showing some recovery

Arlington Reef
Cairns
inner reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Inner reef location affected but shallow areas showing recovery signs

Dunk Island
Mission Beach
inner reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Fringing reefs affected, rainforest runoff helping nutrient recovery

Fitzroy Island
Cairns
inner reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Fringing reefs showed high bleaching, some protected bays recovering

Low Isles
Port Douglas
inner reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Inner reef vulnerable, seagrass beds aiding recovery

Daydream Island Reef
Whitsundays
inner reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Resort's living reef program helping recovery efforts

Michaelmas Cay
Cairns
inner reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024-2025 consecutive mass bleaching

Cay's unique ecosystem combining reef with bird sanctuary, shallow reef affected

Magnetic Island Fringing Reefs
Townsville
inner reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Inner reef location vulnerable, Nelly Bay and Geoffrey Bay trails affected

Green Island
Cairns
inner reef
Moderate Impact
Moderate Impact

Reef Status

Latest Event: 2024 mass bleaching

Inner reef location heavily impacted, high tourist pressure, slow recovery

Lady Musgrave Island
Southern Reef
mid reef
Severe Impact
Severe Impact

Reef Status

Latest Event: 2024 mass bleaching

Lagoon heavily impacted by restricted water flow, outer reef areas better

Lady Elliot Island
Southern Reef
outer reef
Severe Impact
Severe Impact

Reef Status

Latest Event: 2024 mass bleaching

First major bleaching for southern reef, 60% affected, significant Acropora mortality

Understanding Bleaching Scores

Health Status Categories

  • 🟢 Good Condition (70-100%)– Minimal bleaching, diverse marine life
  • 🟡 Moderate Impact (50-69%)– Recovering from bleaching, fish abundant
  • 🔴 Severe Impact (0-49%)– Significant bleaching, slow recovery

2025 Key Findings

  • Consecutive bleaching 2024-2025 - first time for Southern Reef
  • Winter temperatures 1°C above average despite seasonal cooling
  • Only 2 of 124 reefs retain over 75% coral cover
  • Crown-of-thorns active on 27 reefs (additional pressure)
  • Recovery compromised: reefs need 2-5 years but events now every 2 years