Hawaiian crows extinct in the wild return to Maui

After decades of absence, Hawaiian crows, also known as ʻalalā, returned to the wild. Yesterday, five of these rare birds were released on the island of Maui—a significant step in efforts to reintroduce the species to its natural habitat, according to the San Diego Zoo Wildlife Alliance.

The group consists of two females and three males, which had previously spent several months in bird conservation facilities in order to build strong bonds in social groups. Before the release, experts from the San Diego Zoo Wildlife Alliance carefully assessed the animals, especially their ability to forage and to respond to potential predators.

Megan Owen, vice president of conservation science at the San Diego Zoo Wildlife Alliance, said that the release was the result of years of preparation. Numerous organizations and agencies were involved in the project, including the U.S. Fish and Wildlife Service, the Hawaii Department of Land and Natural Resources Division of Forestry and Wildlife, and the University of Hawaii.

The decline of the Hawaiian crow

The Hawaiian crow (Corvus hawaiiensis) already began to decline in the early 20th century. Originally, it was found only on Big Island, but habitat loss due to agriculture and settlement hit the species hard. In addition, its nests were plundered by introduced invasive species such as rats and mongooses, while diseases such as toxoplasmosis, spread by feral cats, and predation by the native Hawaiian hawk (Buteo solitarius) further increased the pressure.

By the 1990s, the Hawaiian crow population had shrunk to only a few dozen birds, and the species was classified as critically endangered. When the last known animals disappeared in the wild in 2002, it was ultimately considered extinct in the wild.

Thanks to intensive conservation efforts, the last surviving Hawaiian crows were rescued and kept in human care. Breeding programs at facilities such as the San Diego Zoo Wildlife Alliance have since slowly but steadily rebuilt the population.

Looking back at previous reintroduction attempts

The first attempts to return Hawaiian crows to the wild took place in the 1990s, when 27 birds raised in breeding programs were released on Big Island. But the mortality rate was high: persecution by the Hawaiian hawk and disease caused a large proportion of the animals to die. The few surviving crows were then recaptured and brought back to the breeding stations.

A renewed attempt was made between 2016 and 2020, when 30 birds were released in the Puu Makaala Natural Forest Reserve on Big Island. Some of these Hawaiian crows survived longer and even showed signs of breeding behavior, but no nesting attempt was successful. As the population declined again, the remaining birds had to be taken back into human care.

With the current relocation to Maui, there is new hope: the island offers similar living conditions to Big Island, but without Hawaiian hawks—one of the main threats in earlier attempts.

New opportunities for the Hawaiian crow on Maui

Maui was deliberately selected as a new habitat for the Hawaiian crow because the island offers ideal conditions and is less affected by the threats that displaced the birds on other islands. The return of the crows is seen as a beacon of hope for restoring Hawaii’s forests. As intelligent omnivores and effective seed dispersers, they play a key role in the ecosystem and help preserve Hawaii’s flora.

The release of the Hawaiian crows marks the culmination of years of intensive preparation. Scientists trained the birds to prepare them for life in the wild, including learning behaviors for foraging and protection from predators. At the same time, work was carried out to control invasive species such as mongooses and feral cats, which could continue to threaten the birds.

Despite this success, the future of the Hawaiian crow remains uncertain. The species is still considered highly endangered, and its long-term survival will require continuous support and protection measures. Disease and invasive species remain potential dangers that could once again cause problems.