It has soft, brownish-black plumage and long, bristly throat feathers; the feet, legs, and bill are black.

Extensive understory cover was necessary to protect the ʻalalā from predation by the Hawaiian hawk, or ʻio (Buteo solitarius).

The main portion of their diet and 50% of their feeding activity is spent foraging on trunks, branches, and foliage for invertebrates such as isopods, land snails, and arachnids.

They feed in a woodpecker fashion, flaking bark and moss from trunks or branches to expose hidden insects, foraging mostly on ohia and koa, the tallest and most dominant trees in their habitats.

Although hoawa and alani fruits have hard outer coverings, crows continue to exert energy prying them open.

Nectar to feed the young is obtained from the ohia flower, oha kepau, and purple poka during the nestling period.

Crows also foraged various plant parts, including the flower petals of kolea, koa, and mamane.

[11][12][13] The Hawaiian crow has a call described variously as a two-toned caw and as a screech with lower tones added, similar to a cat's meow.

The crow typically lays one to five eggs (that are greenish-blue in color) per season, although at most only two will survive past the fledgling phase.

The ʻalalā plays a key role in the maintenance of many indigenous plant species, which now could become a rarity in Hawaii's ecosystems, specifically the dry forests, without their main seed disperser.

[20] ʻAlalā select habitat with ample cover and prefer areas with a large proportion of native plants for food and shelter.

After settlement by Europeans, the higher elevation forest was also compromised by extensive logging and ranching, and farm animals such as cattle, pigs, sheep, and goats being allowed to graze freely in these areas.

[6] Ancient Polynesian cultures valued ʻalalā feathers for use in kāhili and for decorating idols used during the Makahiki season.

For this purpose, professional birdcatchers (known as kia manu) working for King Kamehameha or local priests (ali'i) were known to snare and hunt ʻalalā with poles.

Many Hawaiian bird species have shown precipitous population declines which are thought to be due to avian malaria.

[26] In experimental studies on other native Hawaiian birds, avian pox has been shown to cause large lesions, which often become infected, leading to tissue necrosis.

It is spread by domestic cats, who can transmit eggs and parasites to practically every known warm-blooded vertebrate, including birds, in their feces.

[30] Cats are not native to the Hawaiian islands, and ʻalalā are therefore naive hosts to the parasite; this is often associated with higher virulence and susceptibility.

Attempts to reintroduce captive-bred birds into the wild have been hampered by predation by the Hawaiian hawk (Buteo solitarius), which itself is listed as Near Threatened.

[8] Sites on the slopes of Mauna Loa and other natural ranges have been set aside for habitat reconstruction and native bird recovery since the 1990s.

The Kūlani Keauhou area has been ranked the best spot for the crows, parts of which have been fenced and ungulate-free for 20 years, helping tremendously for habitat recovery.

By 1981, 12 individuals had been brought into captivity due to concerns about the viability of the wild population; 10 were housed in an endangered species breeding facility on Hawaii island.

Difficulties with artificial incubation, issues with males disturbing nesting females, and problems associated with inbreeding, are all thought to have contributed to this low number.

[41] Experimentation with allowing adults to incubate and rear their own chicks began in 2011, and by 2023, 17% of the living population was the product of full parent-rearing.

[8] In December 2016, 5 young ʻalalā were released into the Pu'u Maka'ala Natural Area Reserve on the eastern side of the island of Hawai'i.

It is said to lead souls to their final resting place on the cliffs of Ka Lae, the southernmost tip on the Big Island of Hawaii.