Discover the Fascinating World of the Red Eyed Crab: Habitat, Behavior, and More

Red eyed crabs, also known as Gecarcoidea natalis, are native to Christmas Island in the Indian Ocean. These fascinating creatures get their distinctive red eyes from the algae that live in their eyestalks. This symbiotic relationship between the crab and the algae is crucial for both species’ survival.

The history of red eyed crabs dates back to the earliest inhabitants of Christmas Island, who considered them sacred and believed they brought good luck. Today, these crabs play a vital role in the island’s ecosystem, particularly during their annual migration to the ocean to release their eggs. This phenomenon attracts thousands of tourists each year, boosting the island’s economy and raising awareness about conservation efforts.

One of the most interesting behaviors of red eyed crabs is their synchronization during migration. Despite the sheer number of crabs involved, they manage to move in unison to ensure the safety of their offspring. This cooperative behavior is not only impressive but also serves as a reminder of the importance of working together for a common goal.

Interestingly, red eyed crabs are also known for their ability to adapt to changing environmental conditions. With the increasing threats of climate change and habitat destruction, these resilient creatures continue to thrive on Christmas Island. Their survival serves as an inspiration for conservationists and researchers seeking to protect endangered species worldwide.

While red eyed crabs face challenges in their natural habitat, their unique characteristics and behaviors offer valuable insights into the importance of biodiversity. By studying these fascinating creatures, we can learn more about the interconnectedness of ecosystems and the role each species plays in maintaining environmental balance.

What are the characteristics of a red eyed crab?

The red eyed crab, also known as Cardisoma armatum, is a species of terrestrial crab found in Africa and Madagascar. These crabs are easily identifiable by their bright red eyes, which give them a unique and striking appearance. They have a robust body with a hard exoskeleton, and they are primarily herbivorous, feeding on vegetation such as leaves and fruits.

Red eyed crabs are known for their aggressive behavior, often defending their territories fiercely against other crabs. They are also adept climbers, using their powerful claws and legs to scale trees and shrubs in search of food. In addition to their striking appearance, red eyed crabs are also valued for their ecological role in maintaining the balance of their habitats through their feeding habits.

One of the advantages of red eyed crabs is their adaptability to different environments. They are able to thrive in a variety of habitats, including mangrove swamps, forests, and coastal areas. This adaptability allows them to survive in changing conditions, making them a resilient species.

Overall, the red eyed crab is a fascinating creature with unique characteristics and behaviors. In the following sections, we will delve deeper into the habitat, diet, and behavior of the red eyed crab, providing a comprehensive overview of this intriguing species.

Discover the Fascinating World of the Red Eyed Crab: Habitat, Behavior, and More

The red eyed crab, scientifically known as Gecarcoidea natalis, is a fascinating creature native to Christmas Island in the Indian Ocean. These crabs are known for their bright red eyes, hence their name, and they play a crucial role in the island’s ecosystem.


The red eyed crabs primarily inhabit the rainforests and coastal regions of Christmas Island. During the wet season, they migrate to the coast to breed, where they release their larvae into the ocean. As the dry season approaches, the crabs move back to the rainforest to avoid dehydration.


  • Red eyed crabs are primarily herbivores, feeding on fallen leaves, fruits, and flowers.
  • They are known for their impressive climbing abilities, allowing them to navigate the dense rainforest canopy with ease.
  • During the breeding season, the males will engage in fierce battles to compete for mating rights with the females.
  • These crabs are also known for their synchronized mass migration to the coast, where millions of crabs can be seen moving en masse.


One of the most remarkable adaptations of the red eyed crab is its ability to breathe both on land and underwater. They have specialized gills that allow them to extract oxygen from both air and water, making them incredibly versatile in their habitat.


Despite their adaptability, red eyed crabs face threats from habitat destruction, introduced predators, and climate change. Conservation efforts on Christmas Island are crucial to protect these unique creatures and ensure their continued existence in the wild.

What is the habitat of the red eyed crab?

The red eyed crab is commonly found in mangrove forests and along the coastlines of tropical regions. They prefer areas with plenty of vegetation and saltwater.

What does the red eyed crab eat?

Red eyed crabs are omnivores, meaning they eat a variety of foods. Their diet includes algae, plant matter, small insects, and even carrion.

How big do red eyed crabs get?

Red eyed crabs are relatively small, typically growing to about 2 inches in size. Some larger specimens may reach up to 3 inches.

Are red eyed crabs aggressive?

Red eyed crabs are generally peaceful creatures and not known to be aggressive. However, they may become territorial if kept in a confined space with other crabs.

Can red eyed crabs be kept as pets?

Yes, red eyed crabs can be kept as pets in a suitable enclosure with the proper environmental conditions. It’s important to provide them with a habitat that mimics their natural environment.


Overall, the red eyed crab is a fascinating creature that inhabits the waters of the Atlantic Ocean. From its unique appearance with bright red eyes and orange claws to its interesting feeding habits of scavenging for food on the ocean floor, the red eyed crab is truly a sight to behold. In addition, its ability to blend in with its surroundings using camouflage and its importance in the marine ecosystem as an essential part of the food chain highlight the significance of this species in the ocean.

Furthermore, the red eyed crab’s behavior of being nocturnal and its social nature of grouping together in large numbers for protection demonstrate the intelligence and adaptability of this marine creature. Its resilience in the face of changing environmental conditions and its role in maintaining balance within the ecosystem showcase the importance of conserving and protecting the red eyed crab. Overall, this article sheds light on the unique characteristics and behaviors of the red eyed crab, underscoring the need for further research and conservation efforts to ensure the survival of this remarkable species.