Drastically reducing populations of feral sheep (Ovis aries), mouflon sheep (Ovis musimon), feral-mouflon hybrids, and feral goats (Capra hircus) on Mauna Kea were key management actions done to promote recovery of critical habitat for palila (Loxioides bailleui), an endangered Hawaiian forest bird. Recovery of mamane (Sophora chrysophylla), the dominant tree in much of the subalpine woodland and the most important plant species for palila, was studied inside and outside exclosures. Five years after feral sheep and goat populations were controlled, natural seed and sprout regeneration had established in tree line areas on the west flank of the mountain. Spatial and temporal variability of recovery were observed. Data from the east flank, where mouflon concentrated, showed that mamane recovery will be slower there than on the west side. Palila census data for 1980-88 showed large annual fluctuations in population size, but such fluctuations are probably not correlated with mamane recovery. Tree growth models indicate that recovering stands of mamane may not measurably benefit palila until the 21st century.
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