📸 PhotoPhoto: DIAC images · CC BY 2.0 · Wikimedia Commons Source
Christmas Island red crab
Gecarcoidea natalis (Christmas Island red crab · クリスマスアカガニ)
Not Evaluated (NE) on the IUCN Red List yet.
💡 Everyday Comparisons for Size, Mass & Speed
- 💡 Its maximum size of 12 cm is 3–4 cm longer than the long side of a credit card (about 8.6 cm) (Comparison).
- 💡 The Australian Museum notes that during the annual breeding migration, streets on Christmas Island are covered in red by millions of baby crabs.
Reference standards: coach bus ~12 m, mid-size car ~4.9 m, compact car ~1 t, basketball hoop 3.05 m, credit card 8.56 cm.
📖 1. Overview
The Christmas Island red crab is a red land crab endemic to Christmas Island, with an estimated population of about 45 million individuals.
🦴 2. Anatomy & Morphology
It is a large red crab with a rounded carapace. Both claws are equal in size; males are usually larger, while females have a broader abdomen.
🔍 3. Ecology & Behavior
It feeds on leaves, fruits, flowers, and seedlings, and occasionally eats dead birds or crabs, making it a keystone species of the forest ecosystem. Every year from October to December, swarms leave the forest and migrate to the nearest beach to breed, and females release their eggs into the sea at the turn of high tide during the last quarter of the moon.
🇰🇷 4. Connection to Korea
No direct record connecting this species to Korea has been found.
📚 Sources & References
- • IUCN Red List: not evaluated (NE) — cross-checked with the Wikidata conservation-status entry
- • catalogueoflife.org — 3FGD9
- • wikidata.org — Q1934004
- • commons.wikimedia.org — File:Christmas Island (5774532171).jpg
- • australian.museum — red-land-crab-gecarcoide-natalis
- • Silhouette: PhyloPic — Margot Michaud · CC0 1.0 (Related taxon silhouette — Gecarcinus quadratus)
Recorded dimensions are widely cited representative estimates from public literature and may vary by study or specimen.