Photograph by WaterFrame, Alamy
Map
Red Crab Range
Fast Facts
- Type:
- Invertebrate
- Diet:
- Omnivore
- Size:
- 5 in (12.7 cm)
- Group name:
- Streams
- Protection status:
- None
- Did you know?
- Red crabs can stop traffic, puncture tires, and wander through any open doors during their migration to the sea.
- Size relative to a tea cup:
The red crab is a Christmas Island, Australia, original found nowhere else in the world. But on its home turf it is a very significant species—some 120 million individuals cover the rain forest floor and play a major role in determining the structure of the ecosystem.
These large crabs are active during the day but prefer to stay in the shade and can die in the moisture-robbing heat of direct sunlight. They scavenge on fallen leaves, seedlings, fruits, and flowers, recycling nutrients and helping to determine the spread and composition of native flora.
Most of the year red crabs are solitary dwellers of the burrows they dig throughout the forest. During the dry season they retreat into these shelters to retain body humidity and essentially remain there for two to three months.
But when wet season returns in October or November they begin a legendary mass migration to their seaside breeding grounds, moving in colorful waves that wash over all obstacles including roads (necessitating crab tunnels and road closings) and even seaside cliffs.
The annual trek is also intimately tied to the lunar schedule. The crabs arrive at the coast and mate at such a time that the females can produce eggs and develop them in burrows for a dozen or so days before releasing them into the sea precisely when high tide turns between the last quarter and new moon. During this period sea level on the beaches varies the least and offers an easier approach, a factor so important that if weather delays the migration crabs will put off spawning until the next lunar month.
Red crab eggs hatch right away, and young live as larvae in the sea for a month before returning to the shoreline, molting into air breathers, and slowly returning inland to begin the cycle anew.
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Animals
- Aardvark
- Adélie Penguin
- African Elephant
- African Lion
- African Wild Dog
- Albatross
- Alligator Snapping Turtle
- Amazon Horned Frog
- American Alligator
- American Bison
- American Bullfrog
- American Crocodile
- Ammonite
- Andean Condor
- Anglerfish
- Ankylosaurus Magniventris
- Ant
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- Arctic Fox
- Arctic Hare
- Arctic Skua
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- Coyote
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- Dingo
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- Dolichorhynchops Osborni
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- Dugong
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- Eastern Diamondback Rattlesnake
- Eastern Gray Kangaroo
- Egyptian Giant Solpugid (Camel Spider)
- Electric Eel
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- Elk
- Emperor Penguin
- Fennec Fox
- Firefly (Lightning Bug)
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- Frilled Lizard
- Fur Seal
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- Gelada
- Gentoo Penguin
- Geographic Cone Snail
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- Giant Pacific Octopus
- Giant Panda
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- Gibbon
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- Giraffe
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- Golden Jellyfish
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- Golden Poison Dart Frog
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- Great Blue Heron
- Great Egret
- Greater Flamingo
- Greater Rhea
- Great Horned Owl
- Great White Shark
- Green Anaconda
- Green Basilisk Lizard
- Green-Eyed Tree Frog
- Green Iguana
- Green Sea Turtle
- Grizzly Bear
- Groundhog
- Hammerhead Shark
- Harbor Porpoise
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- Hawksbill Sea Turtle
- Hedgehog
- Henodus Chelyops
- Hesperornis Regalis
- Hippopotamus
- Honeybee
- Horned Toad (Short-Horned Lizard)
- Hornet
- Horse
- Howler Monkey
- Humpback Whale
- Impala
- Indian Rhinoceros
- Ivory-Billed Woodpecker
- Jackrabbit
- Jaguar
- Kemp's Ridley Sea Turtle
- Killer Whale (Orca)
- King Cobra
- King Vulture
- Kinkajou
- Koala
- Komodo Dragon
- Krill
- Ladybug
- Laughing Kookaburra
- Leafy and Weedy Sea Dragon
- Leatherback Sea Turtle
- Leopard
- Leopard Seal
- Leptoceratops Gracilis
- Lesothosaurus Diagnosticus
- Lionfish
- Little Red Flying-Fox
- Llama
- Lobster
- Locust
- Loggerhead Sea Turtle
- Lynx
- Macaw
- Madagascar Hissing Cockroach
- Mallard Duck
- Manatee
- Mandrill
- Marine Iguana
- Matschie's Tree Kangaroo
- Meerkat
- Meller's Chameleon
- Mexican Axolotl
- Mola (Sunfish)
- Mole Rat
- Monarch Butterfly
- Mongoose
- Mononykus Olecranus
- Moose
- Mosquito
- Mountain Goat
- Mountain Gorilla
- Mountain Lion
- Mouse Lemur
- Mudpuppy
- Musk-Ox
- Narwhal
- Nile Crocodile
- North American River Otter
- Northern Leopard Frog
- Nudibranch
- Nurse Shark
- Nutria
- Ocelot
- Olive Ridley Sea Turtle
- Opossum
- Orangutan
- Oriental Fire-Bellied Toad
- Osprey
- Ostrich
- Oyster
- Ozark Big-Eared Bat
- Pachycephalosaurus Wyomingensis
- Parrot
- Parrot Fish
- Peacock
- Pelican
- Peregrine Falcon
- Pileated Woodpecker
- Platecarpus
- Platypus
- Poison Dart Frog
- Polar Bear
- Porcupine
- Portuguese Man-of-War
- Prairie Dog
- Praying Mantis
- Proboscis Monkey
- Pronghorn
- Protosphyraena
- Protostega Gigas
- Przewalski's Horse
- Pufferfish
- Queen Angelfish
- Quetzal
- Raccoon
- Rainbow Trout
- Raven
- Red Crab
- Red-Eyed Tree Frog
- Red-Footed Booby
- Red Fox
- Red Kangaroo
- Red Leaf Monkey
- Red Panda
- Red-Tailed Hawk
- Red Uakari
- Rhesus Monkey
- Right Whale
- Ringed Seal
- Ring-Necked Pheasant
- Ring-Tailed Lemur
- Rockhopper Penguin
- Rocky Mountain Bighorn Sheep
- Ruby-Throated Hummingbird
- Sailfish
- Saltwater Crocodile
- Sandhill Crane
- Sand Tiger Shark
- Scarab
- Scorpion
- Sea Anemone
- Sea Cucumber
- Seahorse
- Sea Otter
- Siberian Tiger
- Sifaka
- Skunk
- Sloth Bear
- Snow Goose
- Snow Leopard
- Snowshoe Hare
- Snowy Owl
- Sockeye Salmon
- Spectacled Bear
- Sperm Whale
- Spider Monkey
- Spotted Hyena
- Spotted Salamander
- Spring Peeper
- Squirrel
- Starfish (Sea Star)
- Steller Sea Lion
- Steller's Sea Eagle
- Stick Insect
- Stingray
- Styxosaurus Snowii
- Sumatran Rhinoceros
- Sun Bear
- Tapir
- Tarantula
- Tasmanian Devil
- Thescelosaurus Neglectus
- Thick-Billed Murre
- Thomson's Gazelle
- Three-Toed Sloth
- Tiger Salamander
- Tiger Shark
- Toucan
- Triceratops Horridus
- Triggerfish
- Troodon Formosus
- Tundra Swan
- Tusotheuthis Longa
- Two-Toed Sloth
- Tylosaurus Proriger
- Tyrannosaurus Rex
- Velociraptor Mongoliensis
- Wallaby
- Wallace's Flying Frog
- Walrus
- Warthog
- Warty Newt
- Wasp
- Water Buffalo
- Web-Footed Gecko
- Weddell Seal
- Western Lowland Gorilla
- Whale Shark
- White-Eared Kob
- White Rhinoceros
- White-Tailed Deer
- Whooping Crane
- Wildebeest
- Wild Turkey
- Wolf
- Wolverine
- Wood Stork
- Xiphactinus Audax
- Zebra
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