Ungulates of Hawaiʻi

Current Range: Hawaiʻi Island

Region of origin: Europe

Date of first introduction: 1791 (Kauaʻi), 1793 (Hawaiʻi Island)

Average size: Female - 20 kg to 40 kg, Male - 25 kg to 60 kg

Litter frequency: 1 to 2 per year

Litter size: 1 to 2 lambs (twinning rare)

Home range: Female - 1.71 ± 0.86 km , Male - 2.07 ± 0.3 km

Diet: Opportunistic grazer (known to browse native shrublands)

2

Feral Sheep (Ovis aries)

References: Scowcroft and Giffin 1983, Tomich 1986, Van Vuren and Coblentz 1989

Identifying Markers

Physical Appearance: Woolly or shaggy coat, often patchy in feral individuals, colors vary (white, brown, black, or mixed), 100–150+ lbs (larger than mouflan), long wooly tail, thick, curved horns in males, and small or absent horn in females.

Tracks: Blunt, heart-shaped prints, about 2.5–3 inches (larger and rounder than mouflon), more common in open grasslands, pastures, and lower elevation dry forests

Scat: Oval to cylindrical pellets, found in loose clusters or scattered piles, frequently near grazing or bedding areas in open fields.

Feeding Signs: Primarily grazers, feeding mostly on grasses and low herbaceous plants, uniformly grazing grasslands near water sources or flat areas (less shrub browsing compared to mouflon).

Environmental Impacts

Feral sheep in Hawaiʻi impact the environment by overgrazing native grasses and lowland plants, especially in dry forests, grasslands, and open pastures. Unlike mouflon, which occupy steep alpine areas, feral sheep stay in lower elevations and graze in larger herds, leading to widespread loss of groundcover, soil compaction, and increased erosion. Their grazing favors invasive grasses and degrades native plant communities, particularly around water sources. This contributes to the decline of dryland biodiversity and long-term degradation of ecosystems in Hawaiʻi.