Bird's Nest Coral Crab (Trapezia guttata) – Complete Care Guide

General Information

The Bird's Nest Coral Crab (Trapezia guttata) is a fascinating and specialized crustacean that has captured the interest of marine enthusiasts and reefkeepers alike. Known for its symbiotic relationship with branching corals, particularly species of the genus Pocillopora, this small crab plays a vital role in coral health and defense. Its bright red coloration with white carapace makes it a visually striking addition to any reef tank.

In the wild, these crabs are found nestled within the branches of their host coral, where they find shelter and protection. In return, they defend the coral from predators such as crown-of-thorns starfish and help maintain its health by removing debris and sediment. This mutualistic relationship makes the Bird's Nest Coral Crab a unique and beneficial inhabitant for reef aquariums.

Care

Caring for Trapezia guttata requires a reef tank with healthy branching corals, as these crabs are highly dependent on their host for survival. They are best suited for established reef systems with stable water parameters and a variety of coral species. While they are relatively hardy, their reliance on coral hosts means they are not suitable for fish-only tanks or systems lacking live coral.

Providing a natural reef environment with plenty of branching corals, such as Pocillopora damicornis, will ensure their well-being. These crabs are small and non-invasive, making them an excellent choice for reef tanks with peaceful inhabitants.

Diet and Feeding

The Bird's Nest Coral Crab primarily relies on its symbiotic relationship with corals for sustenance. It feeds on mucus produced by the coral and small particles of food that become trapped in the coral's branches. In captivity, they can also benefit from supplemental feeding with finely chopped seafood, plankton, or high-quality marine pellets. However, their primary food source will always be their host coral, so maintaining healthy coral colonies is essential.

Behavior and Compatibility

Trapezia guttata is a peaceful and non-aggressive species, making it a great addition to community reef tanks. They are highly territorial towards their host coral and will defend it from intruders, including other crabs or fish that venture too close. This defensive behavior is beneficial for the coral and adds an interesting dynamic to the tank.

These crabs are best kept singly or in pairs, as they can become territorial towards conspecifics if space is limited. They are compatible with a wide range of reef-safe fish and invertebrates, provided their host coral is not disturbed.

Symbiosis

The Bird's Nest Coral Crab is a textbook example of mutualistic symbiosis. It forms a close bond with branching corals, particularly species of Pocillopora and sometimes Stylophora. The coral provides the crab with shelter and food, while the crab defends the coral from predators and keeps its surface clean. This relationship is not only fascinating to observe but also beneficial for the overall health of the reef ecosystem.

Health and Common Issues

Maintaining the health of Trapezia guttata is closely tied to the health of its host coral. Stress or disease affecting the coral will directly impact the crab. Ensuring stable water parameters, adequate lighting, and proper coral care are essential for the crab's well-being.

When selecting a Bird's Nest Coral Crab, look for active individuals with intact limbs and vibrant coloration. Avoid crabs that appear lethargic or have damaged appendages, as these may be signs of poor health.

Habitat

In the wild, Trapezia guttata is found in the Indo-Pacific region, inhabiting coral reefs at shallow to moderate depths. They are most commonly associated with branching corals in sheltered reef environments. Replicating these conditions in captivity, with plenty of live rock and coral structures, will help them thrive.

Common name: Bird's Nest Coral Crab