Home > Islets > Oahu > Mokuauia ISLETS: OAHU > MOKUAUIA Mokuauia (also called Goat Island)   Mokuauia (also called Goat Island) - Photo: C Swenson Mokuauia (also called Goat Island) - Photo: F & K Starr   Mokuauia (also called Goat Island) - Photo: F & K Starr Mokuauia (also called Goat Island) - Photo: F & K Starr   Mokuauia (also called Goat Island) - Photo: R Shallenberger Physical Features Mokuauia (also called Goat Island) is 13 acres in size with a maximum elevation of about 15 feet. It is located in Laie Bay and is separated from Malaekahana State Park by a shallow channel about 400 yards wide. Many visitors kayak across or wade the channel at low tide. Mokuauia is a low, flat island inside the fringing shoreline reef and is composed of raised limestone, sand, and sandy soil. Regulations The islet is a State Seabird Sanctuary managed by the Hawaii DOFAW. Regulations in Hawaii Administrative Rules, Title 13 Chapter 125, protect wildlife and plants and restrict human activities in seabird sanctuaries. Federal law also protects seabirds, shorebirds, and threatened or endangered species. Visitors are required to obey posted signs and to avoid the interior of the island and all bird nesting areas. Birds Years of burrow excavation by nesting seabirds created Mokuauia's bumpy appearance. A 2000 survey estimated over 6,500 breeding adult Wedge-tailed shearwaters (Puffinus pacificus). Surveys in the 1960s, however, documented only a few hundred shearwaters. The reason for the population increase is unknown, although a researcher in 1967 found several campers eating shearwaters. Rats have also been periodically been documented on the islet. Mokuauia is used by migrating shorebirds, including the rare bristle-thighed curlew (Numenius tahitiensis). It is important for visitors to remain on the beaches and paths around Mokuauia's perimeter to avoid crushing any of the thousands of seabird burrows that fill the islet's interior. Plants A 2005 survey recorded 52 plant species, only 16 of which were native. Despite the large number of alien species, the majority of the vegetation cover is native, particularly in windward and shoreline areas where salt spray eliminates many alien species not adapted to harsh seaside conditions. In 2003, the U.S. Fish and Wildlife Service designated critical habitat on Mokuauia for the endangered plant, Sesbania tomentosa (Ohai). Although the plant is not currently present on the islet, establishing a population would be an important step towards species recovery. Insects Alien insect species are dominant, including fire ants (Solenopsis geminata). These and other ant species are the subjects of an ongoing University of Hawaii research project on the effects of alien ants on native islet ecosystems. Intensive insect collecting associated with this project has revealed that even though most of the insects on the islet are introduced, a rare, Native yellow-faced bee (Hylaeus anthracina) is still present. Another aspect of the research was the 2002 experimental broadcast of ant bait to attempt eradication of introduced ants. The broadcast successfully eradicated Big headed ants (Pheidole megacephala), but the eradication was followed by a dramatic increase in the number of fire ants, which had apparently been suppressed by the big headed ants. Marine Organisms Tide pools and rocky intertidal habitat are present around the island. Native shrimp are sometimes found in brackish pools. Human Uses Hawaiian legends tell that Mokuauia, along with the 4 other islets near Laie Point, were created when the demigods Kana and Niheu killed a giant lizard and threw the pieces into the sea. The islet reputedly got its common name, Goat Island, from the days when Laie residents grazed goats there. Mokuauia is one of Oahu’s most easily accessible islets and fishermen, surfers, and picnicers commonly visit, especially on weekends. Swimming at the protected west beach is popular. Threats Heavy public use creates problems with foot traffic, dogs, and the introduction of additional alien species. Burrowing seabirds are vulnerable to being crushed by careless visitors. Dogs, which are illegal on the islet, kill nesting seabirds. In addition, there is a strong chance of people unknowingly transporting alien insects and seeds to the island. Existing weeds like sea grape (Coccoloba uvifera) and ironwood trees (Casuarina equisetifolia) displace native vegetation and alter seabird nesting habitat. Black rats (Rattus rattus) were first documented in 1967 and have likely been present periodically on the islet. Following two years of decreases in shearwater nesting success, black rats were again documented on the islet in March 2006. Hawaii DOFAW is now conducting a rat eradication program on Mokuauia. > Back to top of page Home  Islets  Species  Projects  Outreach  Links  About Us