|Scientific Name:||Bruguiera exaristata|
|Species Authority:||Ding Hou|
|Red List Category & Criteria:||Least Concern ver 3.1|
|Assessor(s):||Duke, N., Kathiresan, K., Salmo III, S.G., Fernando, E.S., Peras, J.R., Sukardjo, S. & Miyagi, T.|
|Reviewer(s):||Polidoro, B.A., Livingstone, S.R. & Carpenter, K.E. (Global Marine Species Assessment Coordinating Team)|
This species is widespread and very common within its range. It is threatened by the loss of mangrove habitat throughout its range, primarily due to extraction and coastal development, and there has been an estimated 23% decline in mangrove area within this species range since 1980. Mangrove species are more at risk from coastal development and extraction at the extremes of their distribution, and are likely to be contracting in these areas more than in other areas. It is also likely that changes in climate due to global warming will further affect these parts of the range. Although there are overall range declines in many areas, they are not enough to reach any of the threatened category thresholds. This species is listed as Least Concern.
|Range Description:||This species is found in Indonesia (including Java, Lesser Sunda Islands, Irian Jaya, Sulewesi, and Kalimantan), northwest Australia, northeast Australia, and Papua New Guinea.|
Native:Australia; Indonesia; Papua New Guinea
|FAO Marine Fishing Areas:||
Indian Ocean – eastern; Pacific – western central
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||This species is considered common in many parts of its range. For example, this species is reasonably well represented amongst the fringing vegetation along tidal waterways throughout northern Australia except along the west Australian coastline where it is infrequently observed (Wells 1983).|
|Current Population Trend:||Decreasing|
|Habitat and Ecology:||This species is found in intermediate to upstream estuarine zones in the high intertidal region. It is shade intolerant with a maximum porewater salinity of 72 ppt, and a salinity of optimal growth of 8 ppt (Robertson and Alongi 1992). This species grows from 3 to 10 m tall.|
|Use and Trade:||This species is sometimes harvested for fodder and fuelwood.|
This species occurs in the high intertidal region, which is usually the first to impacted by human activities and coastal development. Although local estimates are uncertain due to differing legislative definitions of what is a 'mangrove' and to the imprecision in determining mangrove area, current consensus estimates of mangrove loss in the last quarter-century report an approximately 23% decline in mangrove areas in countries within this species range since 1980 (FAO 2007).
All mangrove ecosystems occur within mean sea level and high tidal elevations, and have distinct species zonations that are controlled by the elevation of the substrate relative to mean sea level. This is because of associated variation in frequency of elevation, salinity and wave action (Duke et al. 1998). With rise in sea-level, the habitat requirements of each species will be disrupted, and species zones will suffer mortality at their present locations and re-establish at higher elevations in areas that were previously landward zones (Ellison 2005). If sea-level rise is a continued trend over this century, then there will be continued mortality and re-establishment of species zones. However, species that are easily dispersed and fast growing/fast producing will cope better than those which are slower growing and slower to reproduce.
In addition, mangrove area is declining globally due to a number of localized threats. The main threat is habitat destruction and removal of mangrove areas. Reasons for removal include cleared for shrimp farms, agriculture, fish ponds, rice production and salt pans, and for the development of urban and industrial areas, road construction, coconut plantations, ports, airports, and tourist resorts. Other threats include pollution from sewage effluents, solid wastes, siltation, oil, and agricultural and urban runoff. Climate change is also thought to be a threat, particularly at the edges of a species range. Natural threats include cyclones, hurricane and tsunamis.
|Conservation Actions:||There are no conservation measures specific to this species, but its range may include some marine and coastal protected areas. Continued monitoring and research is recommended, as well as the inclusion of mangrove areas in marine and coastal protected areas. In Indonesia, a number of protected areas and mangrove greenbelts have been designated, detailed guidelines for sustainable forestry have been made, and there have been small reafforestation schemes in some areas (Spalding et al. 1997).|
|Citation:||Duke, N., Kathiresan, K., Salmo III, S.G., Fernando, E.S., Peras, J.R., Sukardjo, S. & Miyagi, T. 2010. Bruguiera exaristata. The IUCN Red List of Threatened Species 2010: e.T178826A7619018. http://dx.doi.org/10.2305/IUCN.UK.2010-2.RLTS.T178826A7619018.en . Downloaded on 14 October 2015.|