Black Teatfish

Holothuria whitmaei is a large sea cucumber, a member of the class Holothuroidea within the phylum Echinodermata, distinguished by a smooth, thick body wall that is black or dark grey dorsally with a pale, wrinkled underside. Adults can exceed 40 centimetres in length and are typically found resting on sandy or reef substrates during the day, becoming more active in feeding at night. As a deposit feeder, it ingests sediment and organic detritus, recycling nutrients and aerating the substrate, a role that contributes to the health of surrounding coral reef and seagrass ecosystems.

The species occurs across the Indo-Pacific region, inhabiting shallow lagoons, reef flats, and seagrass beds within marine neritic waters. It has been recorded in the Philippines, Australia, Guam, and other Pacific and Indian Ocean locations, including waters associated with the United States through its Pacific territories.

Its population has declined sharply due to intensive commercial harvesting for the "trepang" or "beche-de-mer" trade, where it is highly valued and often targeted preferentially over other sea cucumber species. Because it is slow-growing, long-lived, and easily collected by hand in shallow water, populations recover slowly once depleted. Compounding this, coral reef degradation, coastal development, sedimentation, pollution, and warming ocean temperatures are reducing suitable habitat.

Conservation responses include international trade regulation under CITES Appendix II, national fishing bans and quotas in parts of its range, and monitoring programs in some reef systems. Enforcement remains inconsistent across its wide distribution. Given continued harvesting pressure and habitat decline, the species' population trajectory remains uncertain, with recovery contingent on sustained management and reduced exploitation.

Holothuria whitmaei inhabits shallow tropical coral reefs, seagrass beds, and sandy lagoons throughout the Indo-Pacific region. The species is typically found in depths ranging from 1-30 meters, preferring areas with mixed substrates of sand, coral rubble, and seagrass where it feeds on organic matter in sediments.