History of endemic Hawaiian birds: Part I: population histories, species accounts: forest birds: Hawaiian raven/crow ('Alalā)

Abstract

Corvis tropicus is a medium-sized, brownish-black, robust-billed raven/crow endemic to the island of Hawai'i. Very little is known of its distribution and relative abundance during the first 100 years after discovery of the species during the voyage of Captain James Cook in 1778. Observations and collection of specimens from 1887 to 1902 indicate that 'Alalā were common to abundant locally in Kona and Ka'ū districts, being found chiefly in forests from 1700 to more than 3000 feet elevation and conspicuously absent elsewhere. Today, however, the bird is considered rare and in danger of extirpation. Distributional records are shown by U. S. Geological Survey quadrangle. References and names of observers are cited. Completeness of data, bias, erroneous and doubtful records are addressed. Findings are summarized. There is an extensive discussion on nesting. Few and widely scattered breeding groups, apparent low survival of fledglings and immatures, and unprecedented wandering during the contemporary period all suggest continuing depopulation. Captive breeding for reintroduction into restored habitats is the most obvious remaining hope of preserving a self-sustaining wild population.