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Loxioides bailleui
– Endangered
Taxonomy
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Kingdom:
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ANIMALIA
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Phylum:
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CHORDATA
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Class:
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AVES
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Order:
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PASSERIFORMES
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Family:
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FRINGILLIDAE
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Scientific Name:
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Loxioides bailleui
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Species Authority:
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(Oustalet, 1877)
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Common Name/s:
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Assessment Information
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Red List Category & Criteria:
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EN B1ab(i,ii,iii) ver 3.1 (2001)
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Year Assessed:
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2004
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Assessor/s:
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BirdLife International
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Evaluator/s:
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Stattersfield, A., Benstead, P. & Stuart, T. (BirdLife International Red List Authority)
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Justification:
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This species is classified as Endangered because it has a very small range, which is declining in peripheral areas and in habitat quality, owing to grazing by feral ungulates and invasion by alien plants.
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History:
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| 1988 | - | Threatened (Collar and Andrew 1988) |
| 1994 | - | Endangered (Collar, Crosby and Stattersfield 1994) |
| 2000 | - | Endangered (BirdLife International 2000) |
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Geographic Range
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Range Description:
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Loxioides bailleui is restricted to Hawai`i in the Hawaiian Islands (USA), where it was abundant, though locally distributed, until the beginning of the 20th century. In 1997, it occupied an estimated 78 km² and numbered 4,396 birds, mostly on the west slope of Mauna Kea, where 20.5 km² was estimated to hold 72% of the total population2,3,7. Comparison of annual counts from 1980-1996 suggest that the population size is variable (1,584 to 5,6853), with no prevailing trend2. However, although the concentration of birds on the west slope is maintained irrespective of fluctuations4,8, there are declines elsewhere5.
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Countries:
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Native:
United States (Hawaiian Is.)
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Population
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Population Trend:
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Habitat and Ecology
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Habitat and Ecology:
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It is confined to c.2,000-2,850 m, favouring dry mamane and mamane-naio forest. It feeds primarily on mamane seeds, flowers, and insects2, with the availability of mamane seeds affecting productivity and adult survival. In drought years, most birds do not attempt to breed4,5.
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System:
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Terrestrial
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Threats
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Threats:
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The subalpine forest habitat of this species has been severely overbrowsed by feral ungulates, and nests are preyed upon by Short-eared Owl Asio flammeus, feral cats and introduced rats. Worsening weather and food shortages may account for high losses of eggs and chicks at the end of the breeding season2. Introduced grasses suppress mamane regeneration and potentially increase the (already great) threat of fire. Emerging threats include the spread of alien weeds, feral pigs slowing mamane regeneration, and alien insects preying and parasitising native insects5. Demographic patterns of mamane mortality are under investigation, as mamane may be under threat from pathogens10.
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Conservation Actions
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Conservation Actions:
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Conservation measures underway:
The recent removal of goats and sheep from Mauna Kea has allowed regeneration, but it appears that strong site-tenacity might prevent recolonisation. In 1993, some birds were translocated to a new site where predators were controlled and, although many homed back to their capture site, at least two pairs stayed and bred successfully3. An additional 53 birds have been translocated since in three different trials, but there is little to suggest so far that birds will remain indefinitely in a new area10. Another trial took place in 2002, with a large number of birds translocated to test the hypothesis that a more natural social environment and a larger pool of potential mates will encourage more birds to stay and breed10. In 1996 a captive breeding programme was initiated, and a total of 11 palila were reared in 1996, with a further 3 reared in 2000, at the Keauhou Bird Conservation Center10. In 2000 eleven captive-bred birds were hatched from two pairs, with 100% survival, and in 2001 a further three chicks were raised from one breeding pair10. It was hoped that captive-reared palila could be released in 2002 on the northern slope of Mauna Kea10. Hawai`i State and federal agencies have begun programmes to control cats and rats5,9.
Conservation measures proposed:
Establish protocols and make preparations to control fire5. Continue control of mammalian predators (especially feral cats) and herbivores1,5,6. Maintain the development of techniques for captive propagation and introduction to currently unoccupied sites within the former range5. Reforest areas adjacent to the Mauna Kea Forest Reserve and areas where alien grasses and grazing threaten mamane5.
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