By “Sunday Morning” contributing videographer Judy Lehmberg.
Waikamoi Preserve is a 8,900-acre area protected by The Nature Conservancy on the Hawaiian island of Maui. It is part of a ranch, Haleakala Ranch, owned by five generations of the same family since 1888.
The Hawaiian Islands are volcanic in origin and range in age from .43 million to over 5 million years old. Actually some are even older but are no longer above sea level. They are the most isolated islands on Earth, but life still managed to colonize and thrive there. Most plants probably arrived in the digestive system of birds as a seed, or a spore attached to a bird. Others were brought in either intentionally or accidently when Polynesians, and later Europeans, colonized the islands. Because the islands are so remote there are no large native mammals. The only native terrestrial mammal is the Hawaiian hoary bat and the only native marine mammal is the Hawaiian monk seal (see Nature Up Close, December 9, 2016) but there are a variety of native birds and insects, some found nowhere else in the world.
Because islands are isolated they usually have a high degree of endemism — that is, most of the species living there are found nowhere else. Maui (like all of the Hawaiian Islands) has many endemic species, plants and animals found only there. Those species are always vulnerable to extinction because their population is never very high. In fact, of the original 127 species of Hawaiian birds, 71 are now totally extinct and 31 are threatened or endangered. Loss of habitat and invasive species (especially cats, rats, pigs, mongooses and brown tree snakes) have caused much of the decline. Many birds native to islands have few defenses from predators, as they evolved without them.
Waikamoi Preserve and the land surrounding it exemplifies the need for a healthy watershed. A watershed is an area of land that catches water, usually from rain, and drains all of it into a stream or river. As the water moves through the watershed it is filtered by plants and soil and then stored in an underground layer, called an aquifer, and flows through the area in creeks and rivers. Watersheds are essential to all life on land, including humans, as well as all freshwater organisms. The more trees we cut down and the more we allow domestic animals to over-graze land, watershed functions decline, resulting in smaller amounts of clean water.
The forests on the leeward side of Maui are relatively dry….