|Scientific Name:||Heliopora coerulea Pallas 1766|
|Red List Category & Criteria:||Vulnerable A4cde ver 3.1|
|Assessor(s):||Obura, D., Fenner, D., Hoeksema, B., Devantier, L. & Sheppard, C.|
|Reviewer(s):||Livingstone, S., Polidoro, B. & Smith, J. (Global Marine Species Assessment)|
This species is very widespread in the Indo Pacific region and is locally common within its range. However, given its extremely shallow depth range, it is particularly susceptible to bleaching, harvesting for aquarium and curio trade, localized stochastic events, and extensive reduction of coral reef habitat due to a combination of threats. Specific population trends are unknown, but population reduction can be inferred from declines in habitat quality based on the combined estimates of both destroyed reefs and reefs at the critical stage of degradation within its range (Wilkinson 2004). Its threat susceptibility increases the likelihood of being lost within one generation in the future from reefs at a critical stage. Therefore, the estimated habitat degradation and loss of 37% over three generation lengths (30 years) is the best inference of population reduction and meets the threshold for Vulnerable under Criterion A4cde. It will be important to reassess this species in 10 years time because of predicted threats from climate change and ocean acidification.
|Range Description:||This species is widespread in the Indo-Pacific region. It has been reported in Fiji. It can be found from the Red Sea and East Africa to Southeast Asia and Polynesia, including southern Japan, Australia, and throughout the Coral Sea to American Samoa. The largest blue coral stand in the world is thought to be off of Ishigaki Island, in southwest Japan (Zann and Bolton 1985). |
Specific records include:
Madagascar, Lakshadweep, western Thailand, northwestern Australia, Indonesia, Vietnam, Philippines, Yap, Pohnpei (Micronesia), Papua New Guinea, Bismarck Sea - Solomon Islands, Great Barrier Reef (DeVantier and Turak pers. comm.).
Zann and Bolton (1985) present a detailed map of the distribution in the Pacific, which includes the Great Barrier Reef, New Caledonia, Vanuatu, Wallis & Futuna, western Samoa, American Samoa, Tuvalu, the Marshalls, Micronesia and the area between Micronesia and the GBR, also Taiwan, Marianas, Bonin, and Ryukyu Islands of Japan.
Native:American Samoa; Australia; Bahrain; Bangladesh; British Indian Ocean Territory; Cambodia; Christmas Island; Cocos (Keeling) Islands; Comoros; Djibouti; Egypt; Eritrea; Fiji; India; Indonesia; Iran, Islamic Republic of; Iraq; Israel; Japan; Jordan; Kenya; Kiribati; Kuwait; Madagascar; Malaysia; Maldives; Marshall Islands; Mauritius; Mayotte; Micronesia, Federated States of ; Mozambique; Myanmar; Nauru; New Caledonia; Niue; Oman; Pakistan; Palau; Papua New Guinea; Philippines; Qatar; Réunion; Samoa; Saudi Arabia; Seychelles; Singapore; Solomon Islands; Somalia; South Africa; Sri Lanka; Sudan; Taiwan, Province of China; Tanzania, United Republic of; Thailand; Tokelau; Tonga; Tuvalu; United Arab Emirates; United States Minor Outlying Islands; Vanuatu; Viet Nam; Wallis and Futuna; Yemen
|FAO Marine Fishing Areas:|
Indian Ocean – western; Indian Ocean – eastern; Pacific – eastern central; Pacific – northwest; Pacific – southwest; Pacific – western central
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||This coral is generally common throughout its range, although it can also be locally rare. It is known to form large colonies up to 10 km long in Japan and Indonesia (Zann and Bolton 1985, Foster et al. 2006). It is rare in the main archipelago of Fiji, but is considered common near the outlier island of Rotuma, common in Tuvalu, and abundant in Kiribati (Zann, pers comm., Lovell, pers comm.). This species is dominant in the Marshall Islands, prevalent in Kiribati, and uncommon in Ofu lagoon pools (Fenner pers comm.).|
There is no species specific population information available for this species. However, there is evidence that overall coral reef habitat has declined, and this is used as a proxy for population decline for this species. This species is particularly susceptible to bleaching, disease, and other threats and therefore population decline is based on both the percentage of destroyed reefs and critical reefs that are likely to be destroyed within 20 years (Wilkinson 2004). We assume that most, if not all, mature individuals will be removed from a destroyed reef and that on average, the number of individuals on reefs are equal across its range and proportional to the percentage destroyed reefs. Reef losses throughout the species' range have been estimated over three generations, two in the past and one projected into the future.
The age of first maturity of most reef building corals is typically three to eight years (Wallace 1999) and therefore we assume that average age of mature individuals is greater than eight years. Furthermore, based on average sizes and growth rates, we assume that average generation length is 10 years, unless otherwise stated. Total longevity is not known, but likely to be more than ten years. Therefore any population decline rates for the Red List assessment are measured over at least 30 years. See the Supplementary Material for further details on population decline and generation length estimates.
|Current Population Trend:||Decreasing|
|Habitat and Ecology:||This species occurs on shallow reef (generally less than 2 m), exposed reef locations, reef flats and intertidal zones (Richards, pers. comm.). Off the coast of Kenya, this species can occur in generally disturbed or marginal habitat (Hoeksma, pers. comm.).|
This species is collected for the curio and jewellery trade (dried skeletons give blue colour), and the aquarium trade. In 2005, 2,868 pieces of live and 5,787 pieces of raw Heliopora coerulea were exported for the aquarium and curio trade (E. Wood, pers. comm.).
The huge Heliopora stands that extend for almost 10 km in Banda Aceh, Indonesia were the most damaged species of all corals due to the earthquake (Foster et al. 2006).
In general, the major threat to corals is global climate change, in particular, temperature extremes leading to bleaching and increased susceptibility to disease, increased severity of ENSO events and storms, and ocean acidification. In addition to global climate change, corals are also threatened by disease, and a number of localized threats. The severity of these combined threats to the global population of each individual species is not known.
Coral disease has emerged as a serious threat to coral reefs worldwide and is a major cause of reef deterioration (Weil et al. 2006). The numbers of diseases and coral species affected, as well as the distribution of diseases have all increased dramatically within the last decade (Porter et al. 2001, Green and Bruckner 2000, Sutherland et al. 2004, Weil 2004). Coral disease epizootics have resulted in significant losses of coral cover and were implicated in the dramatic decline of acroporids in the Florida Keys (Aronson and Precht 2001, Porter et al. 2001, Patterson et al. 2002). In the Indo-Pacific, disease is also on the rise with disease outbreaks recently reported from the Great Barrier Reef (Willis et al. 2004), Marshall Islands (Jacobson 2006) and the northwestern Hawaiian Islands (Aeby 2006). Increased coral disease levels on the Great Barrier Reef were correlated with increased ocean temperatures (Willis et al. 2007) supporting the prediction that disease levels will be increasing with higher sea surface temperatures. Escalating anthropogenic stressors combined with the threats associated with global climate change of increases in coral disease, frequency and duration of coral bleaching and ocean acidification place coral reefs in the Indo-Pacific at high risk of collapse.
Localized threats to corals include fisheries, human development (industry, settlement, tourism, and transportation), changes in native species dynamics (competitors, predators, pathogens and parasites), invasive species (competitors, predators, pathogens and parasites), dynamite fishing, chemical fishing, pollution from agriculture and industry, domestic pollution, sedimentation, and human recreation and tourism activities.
These non-scleractinian corals are listed under Appendix I and II of CITES. There are no records in the CITES database of exports of non-scleractinians by weight. Parts of this species distribution fall within several Marine Protected Areas within its range.
Recommended measures for conserving this species include research in taxonomy, population, abundance and trends, ecology and habitat status, threats and resilience to threats, restoration action; identification, establishment and management of new protected areas; expansion of protected areas; recovery management; and disease, pathogen and parasite management. Artificial propagation and techniques such as cryo-preservation of gametes may become important for conserving coral biodiversity.
Having timely access to national-level trade data for CITES analysis reports would be valuable for monitoring trends this species. The species is targeted by collectors for the aquarium trade and fisheries management is required for the species, e.g., Marine Protected Areas, quotas, size limits, etc. Consideration of the suitability of species for aquaria should also be included as part of fisheries management, and population surveys should be carried out to monitor the effects of harvesting.
|Citation:||Obura, D., Fenner, D., Hoeksema, B., Devantier, L. & Sheppard, C. 2008. Heliopora coerulea. The IUCN Red List of Threatened Species 2008: e.T133193A3624060.Downloaded on 22 March 2018.|