Ecology of the feral sheep on Mauna Kea/State of Hawaii

Author:

Hawaii Dept. of Land and Natural Resources, Division of Fish and Game

Title:

Ecology of the feral sheep on Mauna Kea/State of Hawaii

Year:

1975

Pages:

90 leaves

Subject:

Feral sheep Mauna Kea Sheep Mauna Kea Wildlife management Hunting

Summary:

A feral sheep study was conducted on the Mauna Kea Game Management Area, Island of Hawaii, from July, 1972 through April, 1975. Emphasis was placed on gathering information regarding the history, reproductive cycle, movement patterns, food habits and habitat use of the Mauna Kea feral sheep. The study area was situated above the 7,000-foot elevation on Mauna Kea. A wooded zone of mamane (Sophora chrysophylla) and naio (Myoporum sandwincensis) was found near the lower boundary along with various species of grasses and forbs. The upper slopes were composed of barren volcanic cinders and lava flows. Feral sheep were well established on Mauna Kea by 1822, only 29 years after their introduction to the island. They apparently came from the Kona slopes of Mauna Loa and Hualalai. Breeding and lambing activities occurred during all months of the year with an increase in lambing during December, January, and February. A corresponding breeding peak also occurred during July, August, and September. A secondary lambing peak of reduced proportions was indicated each year in the fall. Most sheep exhibited a daily vertical movement pattern. They moved down the mountain to feed each morning, then returned to high ground to bed down each night. The sheep seem to adhere to a definite home range. During periods when the game management area was closed, the greatest distance that sheep was seen was 3.2 miles. However, data indicates that traditional home ranges were abandoned during hunting seasons. Food habit studies indicate that the Mauna Kea feral sheep are grazers and browsers. Preferred items were mamane, pukiawe (Styphelia tameiameia), velvet grass (Holcus lanatus), gosmore (Hypochaeris radicata), pualele (Sonchus oleraceus), wallaby grass (Danthonia semiannularis), and pukamole (Epilobium cinereum). Forty per cent of the plant species which were actually observed to be eaten by the sheep were indigenous to the islands. Standing water was not found to be necessary to the survival of feral sheep. This need was apparently satisfied by moisture in the vegetation they consume. Management recommendations for Mauna Kea included the elimination of feral goats and the stabilization of mouflon numbers until further life history information can be obtained. A maximum allowable number of 500 feral sheep was suggested for the entire game management area. This figure was based on known densities of sheep in certain sections of the mountain and the corresponding range conditions.

Collection:

Monographs