Final Comprehensive Conservation Plan - U.S. Fish and Wildlife ...

Hakalau Forest National Wildlife Refuge
Comprehensive Conservation Plan
the māmane forest portions of Mauna Kea. The removal was never completed and today sheep are
still present in the area (Scowcroft and Conrad 1992).
The Refuge estimates that more than 50 sheep are present on the KFU. These animals exist only
above 5,000 ft (USFWS 2008). The impacts of these animals are similar to other ungulates present in
the Hawaiian Islands. They consume the bark, leaves, and seedlings of native plant species, allow the
invasion of noxious weeds, and increase erosion by exposing soil. In particular, sheep have a
preference for legumes such as koa and māmane trees (Scowcroft and Conrad 1992).
Mouflon (Ovis musimon)
Native to the islands of Sardina and Corsica, mouflon are considered to be a wild species of sheep.
These animals have become established on Lāna„i and Hawai„i Island, although the origin of these
populations is unknown (Tomich 1986). In 1962, mouflon were released in the Mauna Kea Forest
Reserve. By 1986, the entire population was estimated to be around 500, with the largest
concentrations occurring on the southeastern and northwestern flanks (Scowcroft and Conrad 1992).
Unlike sheep and goats, mouflon were not included in the court ruling to remove these species from
Mauna Kea during the late 1970s and early 1980s, but were added to the ruling later. Currently, the
highest concentrations of mouflon occur on the eastern slope of Mauna Kea (Tomich 1986) and the
western and southern slope of Mauna Loa. These animals are also present on the KFU (USFWS
2008).
The food habits, grazing and browsing behavior, and ecological impacts of mouflon are similar to
sheep (Scowcroft and Conrad 1992). They generally travel in small groups and have become adapted
to rugged ridges and gully habitats (Tomich 1986).
Donkeys (Equus asinus)
Donkeys are native to northeast Africa and were first recorded in the Hawaiian Islands in 1825. In
1965, two populations of donkeys existed on the Island of Hawai„i. Approximately 50-60 donkeys
were recorded on McCandless Ranch, part of which is now the KFU. An additional 19 donkeys
occurred in the Ka„ūpūlehu-Kīholo lava fields in North Kona (Tomich 1986). Roughly 7-10 donkeys
were later recorded on the KFU (Ball, pers.comm.).
Physically, a donkey resembles a horse with a larger head and longer ears. They thrive in warm, dry
climates. The diet of donkeys primarily consists of grass, but other plants are also eaten. Adult
donkeys have been documented to eat approximately 6,000 pounds of forage annually. Females
produce only 1 young each year and they have been documented to live 25 years on average.
Although donkeys do contribute to ecosystem change and degradation, primary literature on the
impacts of donkeys is sparse. In the Galapagos, donkeys have been reported to cause declines in
plant populations (Carrion et al. 2007). Donkeys have been removed from several islands worldwide,
including San Miguel Island in California and several others in Mexico. Aerial hunting has proven to
be effective in areas with an open canopy, but ground hunting and contraceptive vaccines have also
been used (Carrion et al. 2007).
Chapter 4. Refuge Biology and Habitats 4-91