Red crab. Photo: Wondrous World Images
Red crab. Photo: Wondrous World Images

In 2025, the annual red crab migration is expected to begin in late October. This will result in a major spawning event around 15 and 16 November, followed by a second spawning in mid-December. Baby crabs usually return to shore 3 to 4 weeks after spawning, with further returns possible into February depending on sea conditions.

This forecast is based on current climatic indicators. The exact timing of migration, spawning and return events is dependent on weather and ocean conditions, and can change unexpectedly.

Christmas Island’s most famous crustaceans are extremely important to our forest ecosystems.

Best known for their spectacular annual migration, red crabs actually spend most of the year in one place.

The majority of the island’s more than 100 million red crabs live in moist rainforests, but they can be found in other habitats including shore terraces and even domestic gardens.

Red crabs dig burrows or live in deep rock crevices. They are sensitive to a lack of moisture and rarely leave their burrows during the dry season, plugging the entrance with a wad of leaves.

They mostly eat fallen leaves, fruits, flowers and seedlings. However, they are not strictly vegetarian and will also eat other dead crabs, birds and the introduced giant African snail.

Red crabs contribute to rainforest health by selectively consuming plants, cleaning up leaf litter, turning over the soil and fertilising it with their droppings.

Christmas Island’s red crab migration occurs at the beginning of the wet season every year.

Scientific name

Gecarcoidea natalis