🐟 A world in the atlas

Coral Reefs

Reefs support ~25% of marine species; heat waves cause bleaching.

← The Atlas
Coral Reefs

PHOTO VIA WIKIPEDIA, CC BY-SA

Least ConcernCritically EndangeredExtinct

The picture

Coral reefs cover less than 1% of the ocean floor yet support around a quarter of all marine species. Marine heatwaves cause corals to bleach, but reducing local stressors makes reefs more resilient.

The science

Corals are animals that live in partnership with algae (zooxanthellae) which give them colour and food; heat stress breaks that partnership.

In numbers

<1%Ocean floor covered
~25%Marine species supported

Worth repeating at dinner

Reefs support about a quarter of marine species on under 1% of the seafloor.

- NOAA

Coral colour comes from tiny algae living inside the coral.

- NOAA

What they face

Marine heatwaves

Warmer water triggers mass bleaching.

NOAA

Pollution & runoff

Nutrients and sediment smother reefs.

NOAA

What is already working

Coral restoration

Nurseries grow and outplant heat-tolerant corals.

Reducing local stress

Cutting pollution helps reefs survive heat.

Reasons for hope

Resilient coral found

Heat-tolerant coral strains show promising survival.

Meet them

Ocellaris clownfishStaghorn coralSeahorseParrotfishGiant oceanic manta ray

Small actions that reach them

Refuse one single-use plastic
8M+ tonnes of plastic enter the ocean yearly, harming turtles, seabirds and whales.
~2 min
Have one meatless meal
Animal agriculture is a top driver of land use, emissions and farmed-animal suffering.
~30 min
Donate to a vetted org
Effective orgs turn funds into ranger patrols, habitat and rescue capacity.
~10 min
Walk or bike one short trip
Transport emissions drive the warming that bleaches reefs and shifts habitats.
~20 min
Switch to a green energy plan
Home electricity is one of your biggest footprints - one switch changes it every day after.
~30 min
Switch to reef-safe sunscreen
Common sunscreen ingredients like oxybenzone and octinoxate wash off swimmers and contribute to coral bleaching in popular bays.
~5 min

People doing the big work

NOAA Coral Program ↗Coral Restoration Foundation ↗

Hopeling is also a pocket companion: one fact, one small act a day. Open the app