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Hawaiian honeycreepers (Fringillidae), of the subfamily Drepanidinae, these birds were once quite abundant in all forests throughout Hawai'i. The subfamily Drepanidinae historically consisted of at least 51 species. Less than half of Hawaii's previously extant species of honeycreeper still exist.〔 Threats to species include habitat loss, avian malaria, predation by non-native mammals, and competition from non-native birds.〔 ==Hawaiian honeycreeper threats== The honeycreepers are threatened by recently introduced predation, competition, parasitism, degradation of habitat, and infectious disease including mosquito-borne avian malaria. One of the consequences of the invasive birds is the introduction of avian malaria. The pathogen is primarily transmitted via female mosquitoes who will pass on the disease by biting a susceptible individual after having bitten an infected individual. The main mosquito vector (''Culex quinquefasciatus'') was introduced over a hundred years before the pathogen (''Plasmodium r. capistranoae''), mostly hosted by the blue-breasted quail (''Coturnix chinensis'').〔 Later, two other mosquito species, the Asian tiger mosquito (''Aedes albopictus'') and the bromeliad mosquito (''Wyeomyia mitchellii'') were introduced to the islands.〔 The immune system of the honeycreepers had not been exposed to avian malaria since its common ancestor existed 4 to 5 million years ago.〔〔 Thus, the honeycreepers had not co-evolved with the pathogen to develop resistance as those birds on the mainland did. In the 1970s, the Hawai’i Forest Bird Survey found that native birds had retreated from mid or low elevation forest and had been replaced by exotic species; however, competition was not documented between them and the native species.〔 During the same time, the elevational limit of malaria was established to be approximately 〔 Above this elevation the mosquito vector could not subsist due to the low temperatures. Due to malaria, highly susceptible species must reside at . Global warming may move that line higher until these species no longer have a refuge. Degradation of habitat for the Hawaiian honeycreepers has also been a main cause for the radical decrease in their population numbers. Colonization of the Hawaiian islands has led to extensive deforestation to make way for agriculture, ranching, and other development. Furthermore, where the forests are still intact, introduced domestic pigs and goats have done considerable damage to habitat. Other destructive invasive species include cats, who feed on birds, especially those who are naive to predators (such as Hawaiian honeycreepers). Efforts to conserve the remaining species are of great interest and a couple of different methods have been described. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hawaiian honeycreeper conservation」の詳細全文を読む スポンサード リンク
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