Mokunui is one of the two offshore islands known as the Mokuluas, The northern most island it is the larger of the pair measuring approximately 1000 feet long and 800 feet wide and it reaches a maximum elevation of 225 feet. The western shore has a sandy beach which meets a gradual sloped hillside, the remaining coastline however, is sheer cliffs and rocky benches.

Today Mokunui is a state seabird sanctuary, home to endangered nesting seabirds, migratory shore birds and wildlife such as the Hawaiian Monk Seal. Unfortunately it is also subject to a variety of impacts from invasive plant species and fire ants to numerous human and animal visitors.

Those who explore the island can unkonwingly step on the burrows with eggs or baby birds, or they can bring alien pests or species on their clothing or shoes. The seabirds who nest here have few choices as to areas they can breed undisturbed. Visitors need to keep in mind that they have landed on a sanctuary and there are rules we need to follow to help protect the seabird species.