Birdsnest Coral

Overview

Birdsnest Coral (Seriatopora hystrix) is a colonial stony coral known for its delicate, branching structure that forms tangled, bushy clumps. It is a widespread and common species found throughout the tropical Indo-Pacific, including the Red Sea and East Africa, where it plays a vital role in reef ecosystems.

Appearance

This coral is characterized by slender, tapering branches that often end in sharp, needle-like points. The colony can grow up to a meter across, with branch thickness varying based on environmental conditions; colonies in areas with strong wave action tend to have shorter, thicker branches compared to those in sheltered, turbid waters. The corallites are arranged in neat, orderly rows along the branches, and the coral displays a variety of colors, including cream, pink, yellow, brown, blue, or green.

Distribution & habitat

Seriatopora hystrix is native to the Indo-Pacific region. It thrives in a range of shallow reef environments, including fore-reef slopes, sheltered lagoons, and intertidal reef flats. While it is most frequently encountered in shallow waters, it has been documented at depths reaching up to 180 meters.

Biology & behavior

As a zooxanthellate coral, it maintains a symbiotic relationship with microscopic algae that live within its tissues. The coral's complex, bushy form provides essential shelter for various small marine animals, such as crustaceans and ophiures. Notably, it shares a specialized relationship with gall crabs, which manipulate the coral's growth to create protected breeding chambers. The polyps typically remain retracted during the day and extend at night to feed.