Alectryon macrococcus var. macrococcus
|Scientific Name:||Alectryon macrococcus Radlk. var. macrococcus|
|Red List Category & Criteria:||Critically Endangered C1 ver 3.1|
|Assessor(s):||Bruegmann, M.M. & Caraway, V.|
|Reviewer(s):||Maunder, M. (Plant Conservation Committee) & Hilton-Taylor, C. (Red List Programme Office)|
The population of Alectryon macrococcus var. macrococcus which numbered about 500 plants in 1997, has declined to less than 300 plants (less than 250 mature individuals) and there is continuing decline due to the impacts of invasive species, habitat destruction and fire. Reproduction in the wild is limited.
|Previously published Red List assessments:|
|Range Description:||This variety has been recorded from the Waianae and Koolau Mts. on O'ahu, in Waimea Canyon and Na Pali Coast State Park on Kauai, on Moloka'i and on the Honokowai Ditch Trail on West Maui.|
Native:United States (Hawaiian Is.)
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||Oahu holds the largest subpopulations, which totaled about 400 plants; while fewer than 100 plants existed on Kauai; and only a very few plants on the other islands (U.S. Fish and Wildlife Service 1997). It has disappeared from parts of its former range. There are 27 known subpopulations which at the time of the recovery plan in 1997 numbered about 500 individuals. This has since declined to less than 300 individuals.|
|Current Population Trend:||Decreasing|
|Habitat and Ecology:||This slow growing, relatively long-lived tree occurs in various lowland dry to mesic forest types (360–1,070 m).|
This taxon was once widespread on leeward sides off all the Hawaiian Islands, but is now almost completely eliminated. The main threats in the past included the impacts of feral cattle, goats and pigs; the impacts of invasive alien plant species; damage from the Black Twig Borer (Xylosandrus compactus); and seed predation by rodents.
Current threats include ongoing competition with invasive alien plant species, Schinus terebinthifolia (Christmas Berry) in particular is now replacing all native vegetation on the southern Waianae Mountains and threatens to occupy the range of all the O'ahu subpopulations. The Black Twig Borer is still a major problem, with most subpopulations sustaining some damage from this. Seed predation by invasive alien rodents (Rattus rattus and Mus musculus is an ongoing problem inhibiting regeneration. Feral goats and pigs are impacting the habitat of most subpopulations through grazing, trampling and resultant soil erosion. Accidental fires as a result of military activities are a potential problem for subpopulations in military training areas on O'ahu, Kauai and Maui.
Given the limited size and scattered distribution of the subpopulations, gene pool limitations may depress reproductive vigour and adaptability.
|Conservation Actions:||The whole species is listed on the US Endangered Species Act. Two subpopulations occur on Federal property, eight are on State land, three in areas leased to the Federal government as part of the Makua Military Reservation and five are in a State Conservation District. A Recovery Plan for the species has been published (U.S. Fish and Wildlife Service 1997).|
|Citation:||Bruegmann, M.M. & Caraway, V. 2003. Alectryon macrococcus var. macrococcus. The IUCN Red List of Threatened Species 2003: e.T34045A9834010.Downloaded on 23 May 2018.|
|Feedback:||If you see any errors or have any questions or suggestions on what is shown on this page, please provide us with feedback so that we can correct or extend the information provided|