“Extinction” of a species is tragic and chilling, especially when human activity is implicated. It is one thing to be rendered extinct by a giant asteroid or a multi-millennia global cooling trend. It is quite another when humans are complicit in the demise of a species over a mere couple of centuries or decades.
The recent news that U.S. Fish & Wildlife Service is proposing to remove 23 species — including 11 birds — from the federal Endangered Species list due to extinction has me in a messy battle with my inner conservationist and my abiding capacity for hope. There is such sobering finality in declaring a species extinct, yet I also see some pragmatic arguments for doing so. In this Dawn Chorus, I thought I’d introduce you to the 11 birds on the brink of bureaucratic extinction and ponder the pros and cons of delisting these endangered birds to ‘extinct’ status.
In the following summaries, I adhere to the language in USFWS’s proposed rule and other sources referring to these birds in the past tense. In so doing, I am not necessarily in agreement that they should be delisted and declared extinct.
Bachman’s Warbler
This little jewel of a warbler likely bred in swampy floodplain forests of the southeastern U.S. and Cuba and wintered in a variety of mature wooded habitats, but details are vague. Male Bachman’s had a black patch on the lower throat and chest, a bright yellow belly, and yellow and gray crown. Females had drab olive-yellow underparts. As of the early 1950s, Bachman’s Warbler was described as the rarest songbird native to the U.S. It was listed as endangered in 1967 due to loss of mature forest habitats needed for breeding and wintering. It was last observed in Cuba in 1981.
Bachman’s Warbler song
Bridled White-eye
The Guam Bridled White-Eye was a small, green and yellow warbler-like forest bird with a gray crown and bold white orbital ring. It was a canopy-feeding insectivore found at all elevations on Guam. The Bridled White-eye was reported to be one of the more common birds on Guam from 1900-1930s. The species hasn’t been detected since the last observation in Guam’s Pajon Basin in 1983. Predation by the introduced brown tree snake (Boiga irregularis) is the probable cause for the White-eye’s drastic decline. The brown tree snake is thought to be culpable for the extinction, extirpation, or decline of 13 of Guam’s 22 (59%) native bird species.
Ivory-billed Woodpecker
A majestic bird with striking black-and-white plumage, the Ivory-billed Woodpecker was the largest woodpecker north of Mexico. Its habitat was the extensive, old-growth bottomland hardwood forests of southeastern U.S. and Cuba. Logging of virgin forest tracts, development, hunting, and collecting decimated Ivory-bill populations.
The species was previously (and falsely) declared extinct three times before birds were rediscovered in 1924 (FL), in 1932 (LA), and in 2004 (AR) by Cornell University observers who reported sightings, audio recordings, and a video interpreted to be an Ivory-bill. Among Ivory-bill Woodpecker researchers, the proposal to delist the species is considered premature — even “absurd.” Scientists can prove that something exists, but they can’t prove that something doesn’t exist.
Ivory-billed Woodpecker video
Ivory-billed Woodpecker calls
The next 8 birds proposed for delisting are Hawaiian Island endemics. Their declines are primarily attributed to disease such as avian malaria and pox virus spread from introduced mosquito vectors, as well as habitat loss, climate change, and predation by introduced mammals (rats, mongoose, feral cats).
Kaua’i ‘akialoa
The Kaua’i ‘akialoa was a large (7.5” in length), short-tailed honeycreeper with a very long, down-curved bill used to reach the nectar of lobelias and ‘ohi’a lehua blossoms. Males were bright olive-yellow overall; females were green-gray above with shorter bills. Typical habitats were tropical lowlands or moist montane forests. It was listed as endangered in 1967 and the last confirmed sighting was 1969.
Kaua’i nukupu’u
This medium-sized honeycreeper had a thin, strongly down-curved bill in which the lower mandible was half the length of the upper mandible. The adult male was olive-green with a yellow head, throat, and breast, with black lores and eye-ring; adult female and immature plumage was olive-green on head with yellowish gray underparts. Little is known of its life history other than it was an insectivore and used its bill to extract insects from bark, wood, and epiphytes. It was listed endangered in 1967. The last confirmed observation was 1899, however, skilled observers reported 3 unconfirmed sightings in 1995.
Kauaʻi ʻōʻō
Endemic to the island of Kaua’i, this member of the honeyeater family was 7.7 inches in length, glossy black on the head, wings, and tail; slaty brown on the lower back, rump, and belly; rufous on the upper tail coverts; with a bold white patch at the bend of the wing. Thigh feathers were a rich golden yellow in adults and black in juveniles. It was the only ʻōʻō known to have eyes with yellow irises. It was common in subtropical forests of Kaua’i where it was a cavity-nester and favored the nectar of Lobelia spp. and the ‘ohi’a lehua tree. It was listed endangered in 1967, with 36 individuals known at the time of listing. It was last observed in 1985 and last heard in 1987.
Kaua’i ʻōʻō video
Large Kaua’i Thrush (Kāmaʻo)
This solitaire was ~8 inches total length, with gray-brown upper parts tinged with olive and light gray underparts with a whitish belly and undertail coverts. The species was noted for flying upward, singing a few loud notes, then dropping into the understory. It inhabited moist forests near sea level as well as upland interior mountain forests of Kaua’i. Life history characteristics are mostly unknown. It was listed in 1970, at which time there were an estimated 337 individuals. The last observation of the Kāmaʻo was in 1989.
Maui ākepa
This small (4 inch), insectivorous honeycreeper was endemic to the island of Maui. Adult males were dull brownish-orange to light brownish-yellow in color; females were duller and less yellow. The lower mandible of the ākepa is crossed or offset, presumably to aid in feeding. Its call was a slight quivering whistle ending with a long trill. Its habitat was the wet montane ‘ōhi‘a forests on the northeastern slopes of Haleakalā volcano. It was listed as endangered in 1970 and the last reported sighting was in 1988.
Maui nukupuʻu
The Maui nukupu’u was a small, 5-inch long honeycreeper with a very thin, curved bill, with the lower mandible half the length of the upper mandible. Adult males were olive-green with a yellow head, throat, and breast; females and juveniles had an olive-green head and yellowish-gray underparts. The species inhabited high-elevation wet forests of ʻōhiʻa lehua and koa. Little is known of this bird’s life history. It was listed as endangered in 1970 and the last sighting was in 1996 in the Hanawi Natural Area Reserve.
Moloka’i creeper
This honeycreeper was known only from Moloka’i in the Hawaiian Islands. The Moloka’i Creeper was ~5.5 inches long and had the appearance of a “ball of flame,” as the males were entirely scarlet red. Females were brown with scarlet washes and markings, and juvenile males ranged from brown to scarlet. This species was an insectivore that gleaned vegetation and bark with its short, straight beak in wet, boggy ʻōhiʻa lehua forests. The Moloka’i Creeper was common in 1907, but was considered in danger of extinction by the 1930s. The species was last detected in the Pelekunu Valley in 1963, and was listed as endangered in 1970.
Po`ouli
The Po`ouli, or Black-faced Honeycreeper, was known only from the island of Maui. It was first discovered only as recently as 1973 in high-elevation rainforest on the east slope of Haleakalā. Its estimated population at the time of discovery was ~140 individuals. The Po`ouli was a medium-sized, stocky bird distinct by its brown plumage, broad black mask extending behind the eye, gray crown, and white cheek patch. The bird was described as “unusually quiet.” The species was listed as endangered in 1975. With extinction looming, 3 wild birds were captured to initiate captive breeding, but these efforts were unsuccessful. The last confirmed sighting of a Po`ouli was 2004; 2005 is estimated to be the year of its extinction.
The discussions/arguments FOR and AGAINST declaring these endangered birds extinct are nuanced and difficult. They involve years of research, survey, and scientific assessment. They benefit from the input of a diverse range of experts. I have immense respect for the USFWS biologists that conduct the status reviews and the researchers diligently filling the data gaps. It’s on up the food chain that I reserve my skepticism, especially when a species gets politicized (e.g., Greater Sage-grouse, Wolverine, Gray Wolf).
I want to steer clear of “nuanced and difficult” in this DC, so let me offer a short list of some of the PROS and CONS of declaring these endangered birds EXTINCT.
PROS
- Declaring a species extinct may invoke an emotional realization that what we have lost and will never regain can engender a spirit to preserve and protect what we still have left.
- Delisting extinct species aids the USFWS in prioritizing scarce funding for rapidly declining endangered species and ecosystem-based projects with greater potential for recovery.
- Extinct species no longer meet the definition of an endangered or threatened species under ESA, thus removal is legally warranted.
CONS
- Extinction can’t be proven.
- Many respected ornithologists are confident the Ivory-billed Woodpecker exists based on cumulative evidence, including audio, video, visual encounter, photographic, and other documentation.
- Many of the habitats used by the species proposed for delisting are remote and difficult for humans to access, thereby, these birds can evade detection.
- By delisting extinct birds that are representative of critically important and legally protected ecosystems (think Ivory-billed Woodpecker and contiguous old-growth forests of the Southeast), pressure is taken off land managers to preserve these habitats for the target bird and other species that also depend on these habitats.
Let these bounce around in your head; add your own pros/cons in the comments below — and if you’d like to offer input to the USFWS on their proposed rule, you can leave it HERE — by November 29, 2021.
Your turn: What’s the word on birds in your world?