Mouflon sheep and rare plants on the island of Hawaiʻi, with an analysis of state ungulate management

Abstract

Mouflon sheep (Ovis gmelini musimon), released in the 1960s for hunting, have been increasing in number and range, and represent a unique conservation threat on Hawaiʻi. Mouflon can jump fences built to exclude other ungulates, are habitat generalists, and are challenging to control. This study maps the distribution of mouflon islandwide and examines the risk to rare native plants and their habitat as mouflon range increases. Mouflon range now encompasses the entire central portion of the island. Because this has serious implications for rare plant recovery, the study also examines the policies and management practices under which this large range expansion of a state-regulated invasive ungulate occurred. The analysis reveals that Hawaiʻi's policy framework is not supportive of future ungulate control, or, by extension, rare plant recovery. This is important to consider in light of the recent discovery of axis deer (Axis axis) on the island.