|Scientific Name:||Psammocora stellata|
|Species Authority:||Verrill 1868|
Psammocora brighami Vaughan 1907
|Red List Category & Criteria:||Vulnerable A4ce ver 3.1|
|Assessor(s):||Cortés, J., Edgar, G., Chiriboga, A., Sheppard, C., Turak, E. & Wood, E.|
|Reviewer(s):||Livingstone, S., Polidoro, B. & Smith, J.|
The most important known threat for this species is extensive reduction of coral reef habitat due to a combination of threats. However, this species is also moderately susceptible to bleaching and crown-of-thorns starfish predation. Specific population trends are unknown but population reduction can be inferred from estimated habitat loss (Wilkinson 2004). This species is very widespread and locally common within its range, can recover quickly from bleaching or other disturbance events, and therefore is likely to be more resilient to habitat loss and reef degradation because of an assumed large effective population size that is highly connected and/or stable with enhanced genetic variability. Therefore, the estimated habitat loss of 32% from reefs already destroyed within its range is the best inference of population reduction since it may survive in coral reefs already at the critical stage of degradation (Wilkinson 2004). This inference of population reduction over three generation lengths (30 years) is the best inference of population reduction and meets the threshold for Vulnerable under Criterion A4 ce. It will be important to reassess this species in 10 years time because of predicted threats from climate change and ocean acidification.
|Range Description:||In the Indo-West Pacific, this species is found in the Seychelles, Indonesia, the oceanic west Pacific, the Hawaiian Islands and Johnston Atoll, and the far eastern Pacific including Easter Island.
In the Eastern Tropical Pacific (ETP) region, Psammocora stellata is recorded from Mexico, Costa Rica, Panama, Colombia, and Ecuador.
In the ETP specific records include:
Mexico: Baja California Sur, Nayarit, Jalisco, Colima (including the Revillagigedo Islands), Michoacán and Guerrero (Reyes-Bonilla 2002, Reyes-Bonilla et al. 2005, Reyes-Bonilla 2003, Glynn and Ault 2000, Glynn 1997, Pérez-Vivar et al. 2006, Reyes-Bonilla and López-Pérez 1998).
Costa Rica: Islas Murciélago Archipelago, Culebra Bay, La Penca, Brasilito Bay, Cabo Blanco, Curú Bay, Punta Mala, Manuel Antonio, Marino Ballena National Park, Osa Peninsula, Golfo Dulce, Caño Island, Cocos Island (Cortés and Guzmán 1998, Cortés 1990, Bernadette et al. 2006, Alvarado et al. 2005, Glynn and Ault 2000, Glynn 1997, Reyes-Bonilla 2002, Reyes-Bonilla et al. 2005), Clipperton Atoll (Glynn and Ault 2000).
Panama: Coiba Island, Uva Island, Unnamed Island in the Gulf of Chiriquí, and Iguana Island, Taboga Island and Saboga Island in the Gulf of Panama (Holst and Guzmán 1993, Maté 2003, Guzmán et al. 2004, Glynn and Ault 2000, Glynn 1997, Reyes-Bonilla 2002, Reyes-Bonilla et al. 2005).
Colombia: Gorgona Island, Ensenada de Utría and Tebada (Zapata and Vargas-Ángel 2003, Glynn and Ault 2000, Glynn 1997, Reyes-Bonilla 2002, Reyes-Bonilla et al. 2005).
Ecuador: La Libertad and Sucre Island at mainland Ecuador, and Devils Crown, Floreana; Wolf Island; Darwin Bay, Genovesa Island; Gardner Bay, Española; Marchena (Hickman 2005, Wells 1983, Glynn 2003, Glynn and Ault 2000, Glynn 1997, Reyes-Bonilla 2002, Reyes-Bonilla et al. 2005).
Native:Chile; Colombia; Costa Rica; Ecuador; El Salvador; Guadeloupe; Guam; Honduras; Indonesia; Japan; Mexico; Micronesia, Federated States of ; Nicaragua; Northern Mariana Islands; Palau; Panama; Seychelles; United States Minor Outlying Islands
|FAO Marine Fishing Areas:||
Indian Ocean – western; Pacific – eastern central; Pacific – northwest; Pacific – southeast; Pacific – western central
|Range Map:||Click here to open the map viewer and explore range.|
This species is rare to uncommon in the Indo-West Pacific.
In the Eastern Tropical Pacific region the relative abundance of Psammocora stellata has been categorized as common in many parts of its range including Mexico, Costa Rica, and Panama. It is considered rare in Clipperton Atoll and mainland Ecuador, and P. stellata was common in the Galápagos (Wells 1983) before the 1982-83 El Niño event (Hickman 2005), and although it is still locally common.
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 more resilient to some of the threats faced by corals and therefore population decline is estimated using the percentage of destroyed reefs only (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 of 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. Follow the link below for further details on population decline and generation length estimates.
|Habitat and Ecology:||
Psammocora stellata occurs on shallow wave washed rock, or at depths of 15-20 m depth on coarse sand bottoms (Hickman 2005).
In general, Psammocora species are very slow growing corals; with a calculated growth rate of 0.6cm/year for P. superficialis in Costa Rica (Guzmán and Cortés 1993; Guzmán and Cortés 1989). Sexual reproduction is important, but asexual reproduction and fragmentation are more effective strategies for colonizing free areas within the reef (Cortés and Guzmán 1998). Psammocora species are considered to be amongst the most opportunistic species because of the capacity to rapidly recolonize open areas after disturbances (Guzmán and Cortés 2001).
The total number of corals (live and raw) exported for this species in 2005 was 5.
The sea star Acanthaster planci and the fish Arothron meleagris feed on Psammocora species (Cortés and Guzmán 1998,Reyes-Bonilla et al. 1999). According to Cortés and Guzmán (1998), the puffer fish Arothron meleagris is capable of reducing populations of Psammocora species if other preferred coral species such as Porites lobata are absent.
In Galápagos, following the 1982-83 El Niño event P. stellata experienced extreme population reductions at Española Island (Glynn 1997); in Costa Rica, after the 1991-92 ENSO event ~40% of all colonies were dead in Manuel Antonio (Jiménez and Cortés 2001), and after the 1997-98 El Niño event P. stellata disappeared from one locality (Punta Cambial) in Costa Rica (Jiménez and Cortés 2003). Despite the fact that Psammocora stellata is affected by ENSO events, this species is more resistant to bleaching than shallow water corals such as Pocillopora (Feingold 1995). Additionally, Psammocora stellata has also shown resistance to anomalous conditions during ENSO events (Feingold 1995, Feingold 1996, Jiménez et al. 2001). At Devils Crown, Floreana (Galápagos), Psammocora stellata bleached during the 1982-83 El Niño event but did not die (Robinson 1985).
Algae overgrowth has also been reported to cause mortality on Psammocora (Glynn 1997, Jiménez and Cortés 2001, Bernadette et al. 2006). At Uva Island, Panama, large aggregations of P. stellata at 8-10 m depth that survived the 1982-83 El Niño event were overgrown by thick mats of Caulerpa species (Glynn 1997); additionally, in Manuel Antonio, Costa Rica, Psammocora species were completely overgrown by a brown algae (Jimenez and Cortés 2001). At La Penca (Costa Rica), Psammocora-dominated reef that once covered 0.3 ha is now reduced to several small (1-3m2) patches of coral among a dense bed of Caulerpa (Bernadette 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 crown-of thorns starfish, disease, and a number of localized threats. The severity of these combined threats to the global population of each individual species is not known.
Crown-of-thorns starfish (COTS) (Acanthaster planci) are found throughout the Pacific and Indian Oceans, and the Red Sea. These starfish voracious predators of reef-building corals, with a preference for branching and tabular corals such as Acropora species. Populations of the crown-of-thorns starfish have greatly increased since the 1970s and have been known to wipe out large areas of coral reef habitat. Increased breakouts of COTS has become a major threat to some species, and have contributed to the overall decline and reef destruction in the Indo-Pacific region. The effects of such an outbreak include the reduction of abundance and surface cover of living coral, reduction of species diversity and composition, and overall reduction in habitat area.
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.
All corals are listed on CITES Appendix II. 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:||Cortés, J., Edgar, G., Chiriboga, A., Sheppard, C., Turak, E. & Wood, E. 2014. Psammocora stellata. The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org>. Downloaded on 22 November 2014.|