Creature Feature: Coral CrabsAndrew Hosie's blog | Created 1 decade agoThe Armoured Defenders Squad: Coral Crabs Living on the coral reefs of Western Australia is a group of specialised crabs that live in a symbiotic relationship with branching hard-corals like Pocillopora and Acropora. This group of crabs, collectively known as coral crabs, is made up from two closely related families: Trapeziidae and Tetraliidae. If you look closely you should be able to find these crabs living in the Pocillopora colonies around Rottnest Island. By making their homes in the branches of corals they gain a hiding place from the many predators that would like to feed upon them. The crabs feed on the nutrient-rich mucus produced by the corals, but do not harm the host. The crabs, particularly species of the genus Trapezia, are normally found as a single pair inhabiting a coral host. The monogamous pair will aggressively defend their territory, but only from members of the same sex. Interestingly, the crabs don’t seem to mind if a pair of a different species of crab moves in. This defensive behaviour doesn’t stop at potential rivals. In return for the protection of the coral branches the crabs will also actively defend the coral from seastars such as the Crown of Thorns, Acanthaster planci which is a major predator of corals. The crabs use their pincers to attack the seastar’s tube feet and spines. Despite the massive difference in size these feisty crabs are able to drive the predator away. Coral crabs from Western Australia clockwise from top left: Trapezia rufopunctata, Trapezia serenei, Trapezia septata, Tetralia nigrolineata, Tetralia sp. and Tetralia cinctipes. Photo credits: Andrew Hosie, Gary Morgan and Clay Bryce. Image copyright of Andrew Hosie, Gary Morgan and Clay Bryce In the below video, between 13:27 - 14:42 there is some fascinating footage of these crabs attacking a Crown of Thorns. 16 Jun 2010Life on the Edge Down UnderToday, a busy port servicing gas refineries and mineral-ore processing continues to develop in the Dampier. It provides scientists from the Western Australian Museum with the unique opportunity to observe and document the effects of industry on the surrounding natural habitats and marine wildlife. Journey through natural and man-made habitats as the researchers reveal the expected and the unexpected. Looking at both the common and the bizarre, the scientists observe and study wildlife, from sharks to shrimps and worms to whales.Read more Video Western Australian Museum
16 Jun 2010Life on the Edge Down UnderToday, a busy port servicing gas refineries and mineral-ore processing continues to develop in the Dampier. It provides scientists from the Western Australian Museum with the unique opportunity to observe and document the effects of industry on the surrounding natural habitats and marine wildlife. Journey through natural and man-made habitats as the researchers reveal the expected and the unexpected. Looking at both the common and the bizarre, the scientists observe and study wildlife, from sharks to shrimps and worms to whales.Read more Video Western Australian Museum