Great Barrier Reef — Ecosystem
The Great Barrier Reef is not just a coral reef — it is the largest living structure on Earth, visible from space, and an ecosystem of incredible complexity.
The Reef in Numbers
- 2,300 km in length (like the distance from Munich to Cairo)
- 2,900 individual reefs and 900 islands
- 1,625 fish species, 600 coral species, 30 whale and dolphin species
- 6 of 7 sea turtle species breed here
- Area: 344,400 km² — larger than Germany
Threats
The reef is fighting for survival:
- Coral Bleaching: Rising water temperatures (0.5–1.5°C above normal) stress the corals, causing them to expel their symbiotic algae and turn white. Mass bleaching events in 2016, 2017, 2020, 2022, and 2024 affected large parts of the reef.
- Crown-of-Thorns Starfish: These starfish consume corals at a rapid pace. Outbreaks are fueled by nutrient runoff from agriculture.
- Climate Change: The greatest long-term threat. The science is clear: Without drastic emissions reductions, the reef will be severely damaged by 2050.
The good news: Despite the bleaching events, there are areas of the reef that are recovering. The outer reefs (where most tourists snorkel) are often in better condition than those near the coast. Scientists are working on heat-resistant coral species and restoration programs. A visit to the reef supports conservation — tourism revenue funds research and protection efforts.