Ula-ai-hawane

The Hawaiian island chain once harbored 57 species of honeycreepers

Honeycreepers (Drepanidini), a tribe within the finch family (Fringillidae), occur only on the Hawaiian island chain. As a sister group, the honeycreepers are closely related to the rosefinches (Carpodacus), yet many species have developed traits that differ from those of finches. Honeycreepers show great morphological diversity—the result of adaptive radiation in an island environment.

A report on speciation in Hawaiian honeycreepers (2011) shows that their ancestors came from Asia and split from the rosefinches around 7.2 million years ago. Biologist Heather R. L. Lerner and other scientists suspect that the ancestors of the honeycreepers arrived on the Hawaiian Islands about 5.2 to 7.2 million years ago. From the rosefinches, different lineages and genera of honeycreepers then evolved on the individual islands at different times.

As is so often the case with island birds, the specialization that enables them to survive in large numbers and in different forms within a limited area becomes a vulnerability when threats or competitors appear. David Day wrote in The Doomsday Book of Animals in 1981 that the honeycreepers with the largest ranges and without significant regional variation were best able to survive.

Today, 24 genera of honeycreepers are distinguished, with around 57 species as well as some subspecies. Roughly 18 species became extinct in prehistoric times, and 21 species probably disappeared more recently. All other species are highly endangered or threatened with extinction. As a monotypic species, the Ula-ai-hawane is one of the extinct honeycreepers.

In Hawaii, not only many bird species have gone extinct, but also many insects and snails. For example, the second-largest endemic moth species, the Kona giant looper, the Koolau spur-winged long-legged fly, or the tree snails Achatinella buddii and Achatinella apexfulva disappeared in the early 20th century.

Ula-ai-hawane – fact sheet

alternative name	ʻUla-ʻai-hāwane
scientific names	Ciridops anna, Fringilla anna
original range	Big Island (Hawaii)
time of extinction	1892
causes of extinction	habitat loss, introduced animals on islands, loss of food plants, introduced diseases
IUCN status	extinct

Different bill shapes: nectar-feeders and seed-eaters

Through adaptive radiation, honeycreeper species have been able to evolve different bill shapes over the course of evolution. With differently shaped bills and tongues, birds can specialize on different plants or foods and thus fill a large number of ecological niches. Pointed bills, for example, indicate that the birds feed on insects and/or nectar; long, downward-curved bills are usually used to obtain nectar from flowers; and forceps-like bills possibly indicate a specialization on snails as food.

The Ula-ai-hawane had a thick, short bill. It fed on the seeds and flower nectar of the hawane tree (Pritchardia). Its name also indicates this, because Hawaiians refer to the Ula-ai-hawane as Ula-Ai-Hawane, which means something like “the red bird that feeds on the hawane berry”. With its tubular tongue, it could suck nectar from the tree’s flowers.

The German common name Annakleidervogel and the specific epithet anna go back to Anna Cate Dole. She was the wife of the lawyer and later Hawaiian governor Sanford Dole, who discovered the Ula-ai-hawane in 1859 and described it in 1879.

A bird “of a tempestuous nature”

The Ula-ai-hawane inhabited forests in the hills and mountains on Big Island, Hawaii’s main island. It is known from the districts of Kona and Hilo and it occurred in the area of the extinct Kohala volcano. Even at the time of its discovery, the Ula-ai-hawane was considered rare.

Among honeycreepers, nectar-feeders and seed-eaters are generally distinguished. The Ula-ai-hawane belonged to the nectar-feeders, which are usually colored black and red. No information at all is available about the Ula-ai-hawane’s way of life and behavior. Only the British ornithologist Robert Cyril Layton Perkins, who mainly studied Hawaii’s fauna, noted in 1903 in Fauna Hawaiiensis that the Ula-ai-hawane was a shy and difficult-to-collect bird “of a tempestuous nature”.

Since the arrival of the first people on the Hawaiian Islands from the late 1st millennium AD, the number of honeycreepers steadily declined. In the two centuries after Europeans discovered the island archipelago in 1778, even more honeycreeper species disappeared.

The last record of the Ula-ai-hawane dates from 20 February 1892. Bird collector Henry C. Palmer, who worked on behalf of the British banker and zoologist Walter Rothschild, shot the bird in the swampy montane forests on Mount Kohala on Big Island.

Ornithologist George Campbell Munro claimed to have seen a bird in the same area in 1937 that showed the characteristic coloration of the Ula-ai-hawane. Later, however, he was no longer sure whether it had actually been this species. In 1960, Munro wrote about the encounter in Birds of Hawaii:

“The black head and gray neck are a striking feature (…) the fleeting observation of a bird’s head and neck that showed this characteristic coloration makes me almost certain that I saw one in 1937 (…). It is unlikely that I saw this bird; nevertheless, it is possible.”

Causes of extinction: deforestation, invasive species, disease, loss of food plants

The IUCN considers the main cause of the Ula-ai-hawane’s disappearance to be the deforestation of Big Island, for example to convert natural landscapes into agricultural land. This may also have led to a particularly high number of rats, to which the Ula-ai-hawane population was exposed. Rats are also known to steal birds’ eggs. Other animals kept on Big Island also destroyed the habitat of the endemic wildlife, especially in the mountains where introduced livestock grazed (such as cattle, pigs, goats or red deer).

The conservation organization also cites the emergence of avian malaria as a cause of extinction, a parasitic bird disease caused by single-celled blood parasites (plasmodia). Most often, mosquitoes transmit the parasites to birds. The study Avian Malaria in Hawaiian Forest Birds (2015) examines the influence of avian malaria on Hawaii’s birds and finds evidence that introduced avian malaria led to the decline and extinction of many endemic forest birds. Besides avian malaria, avian pox, a highly contagious and often fatal viral disease, is considered one of the diseases that reached the Hawaiian Islands with non-endemic birds.

Some scientists assume that the Ula-ai-hawane primarily fed on the unripe fruits of Pritchardia species endemic to Big Island. The birds were often observed near these fan palms, so they may have depended on them. Many fan palms of the genus Pritchardia, which—with few exceptions—occur exclusively on the Hawaiian Islands, are now very rare, endangered or have been missing for years. Researchers therefore suspect that the gradual disappearance of the palms may also have contributed to the Ula-ai-hawane’s extinction.

David Day also considers direct persecution by humans as a cause of the honeycreepers’ disappearance. Some birds of this tribe were hunted for their beautiful feathers—and the rarer the birds became, the more sought-after their feathers were for bird collectors. Thus the mamo or king honeycreeper (Drepanis pacifica) also died out. Its yellow feathers were used to make royal hats and cloaks.