Northern Prairie Wildlife Research Center
Johnston Island, Pacific Islands
Two unique forms of marine life found at Johnston Atoll are protected under Federal laws for threatened and endangered species. These species are the green sea turtle, Chelonia mydas, and the Hawaiian monk seal, Monachus schauinslandi.
Sea turtles are reptiles that spend their entire lives at sea except for brief visits ashore to deposit their eggs in pits dug in sandy areas above the high tide mark. The new hatchlings can fit in the palm of a hand, but the adults can grow to 300-400 pounds and may take 30-40 years to reach breeding maturity. Turtles are highly vulnerable to human predation and disturbance. Many turtles at Johnston have been tagged by researchers seeking to understand migration routes and estimate growth, reproduction, and mortality. Tag recoveries of nesting females on a beach at French Frigate Shoals indicate the Johnston population probably nest there, and no nesting activity has been recorded at Johnston.
|Photo courtesy of Johnathan Bird of|
The Oceanic Research Group
The monk seal, found primarily in the Northwest Hawaiian Islands, occasionally occurs at Johnston. The species has declined sharply in historical times as a result of human harvesting and disturbance of breeding colonies. They feed on fish and crustaceans from the reef and lagoon and, although able to spend long periods at sea, often haul out on sandy beaches to bask in the sun.