Hawaii’s emptying skies – by Matt Stanfield

Paintings of Oahu akialoa (top) & Lanai akialoa (bottom). Images public domain

Not long ago, the Hawaiian archipelago supported a plethora of pollinating birds. Today, many are extinct, with others feared lost or experiencing worrisome declines. Since the early nineteenth-century, twelve of Hawaii’s specialist avian nectar-eaters have become extinct, leaving at most eight known species behind. Seeing images of all twelve of these birds gathered together in one place is an effective and affecting way of getting a true sense of Hawaii’s losses.

The Hawaiian Islands are thought to have first been settled fewer than eight hundred years ago, at the tail end of Polynesian expansion across the Pacific. The arrival of humans in these isolated ecosystems bought with it our species’ calling card: an extinction pulse. The Polynesians, along with the pigs, dogs, chickens and rats who accompanied them, are thought to have been responsible for the loss of many lifeforms.

European arrival from the late eighteenth-century onwards contributed its own wave of death and destruction. Smallpox and other diseases killed many native Hawaiians, and the fauna of the islands experienced further depletion.

Hawaiian nectarivorous birds are divided into two groups: honeycreepers and honeyeaters (though the latter are no relation of the other bird species which are referred to as honeyeaters) Akialoa were honeycreepers, in a genus containing four living members when Europeans arrived in Hawaii. Today all are gone.

The Lanai akialoa disappeared first. Its decline seems to have predated European arrival, as fossils suggest it once inhabited other islands besides Lanai. Habitat loss and the ongoing damage wrought on Hawaii’s ecosystem by the Polynesians’ pigs likely doomed it.

Oahu’s akialoa fared a little better, with the last report dating from 1940. Forest clearance for American sugarcane ventures deeply damaged these birds. They also suffered a more sinister scourge: avian influenza. Spread by mosquitoes, who may have arrived in the bilge water of whaling ships, this disease continues to ravage Hawaiian avifauna to this day.

Paintings of Hawaii mamo (top) & black mamo (bottom). Images public domain

The Big Island’s Hawaii mamo was imperilled before James Cook’s 1778 landfall on the archipelago. The birds’ six to eight yellow feathers were used to manufacture garments for Hawaiian nobles and royalty. One particular cloak may have cost an obscene sixty thousand mamo their lives. Still, the Hawaii mamo might yet live today without the bitter blows dealt by European-led deforestation for cattle ranching, and avian flu.

Often seen with a pollen-dusted forehead after feeding on lobelia flowers, the black mamo, whose range had already been reduced by the Polynesians, was scientifically described in 1893. The last recorded bird was shot fourteen years later. The introduction of cattle, deer and mongooses is blamed for the loss of this species.

Taxidermic greater amakihi. Image public domain

Eating both nectar and insects, the greater amakihi does not appear to have been known to the natives of Hawaii’s Big Island. Western collectors discovered this bird perhaps only a decade before Western investors destroyed it. Scientifically described in 1892, the species was last recorded in 1901, just before its tiny home range was cleared to make way for a sugarcane plantation.

Painting of female (left) & male (right) Laysan honeycreepers. Image public domain

The Laysan honeycreeper, which favoured the nectar of its island’s native flowers, was last recorded in 1923. Europeans, not Polynesians, seem to have been the first people to settle Laysan. Just one of them served to seal the birds’ fate: Max Schlemmer, who released rabbits there in the 1890s, hoping to use them for meat. The rabbits bred explosively, eradicating most of the vegetation on which the Laysan honeycreepers fed.

Taxidermic lesser akialoa (top) & Kauai akialoa (bottom). Images public domain

So far as can be gleaned, none of the akialoa species were common by the time Europeans reached the Hawaiian Islands. Both of these pollinators were ultimately undone by the sugarcane industry’s ruination of forests working in tandem with the invisible spread of mosquito-borne avian diseases. The lesser akialoa has not been reported since 1940. In 1969, when the ultimate agent of its demise first walked on the moon, the Kauai akialoa was last reported. With its passing, the entire akialoa genus ended.

Taxidermic kioea. Image public domain

Whilst gravely damaged by human activity, several nectarivorous Hawaiian honeycreepers yet persist. The Hawaiian honeyeater family (Mohoidae) was less fortunate. They are generally thought to be the only avian family extinct in modern times. Even within an order as large as that of the perching birds, losing a whole family is significant. For instance chameleons, in all their distinctiveness, represent a single family amongst Earth’s snakes and reptiles. The kioea, last recorded in 1859, is thought to have been a victim of logging, introduced species and hunting.

Paintings of Oahu Oo (top) & Hawaii Oo (bottom). Images public domain

Black, yellow and beautiful, these two species have been extinct for some time. The Oahu Oo vanished nearly two hundred years ago, last being recorded in 1837. Hunting by native Hawaiians for its yellow feathers may have contributed, though the prime causes of extinction are thought to have been introduced disease and habitat destruction in the wake of European contact. The Hawaii Oo was last recorded in 1934, suffering a similar fate to its relative on Oahu.

Taxidermic Kauai Oo (top) & Bishop’s Oo (bottom). Images public domain

Bishop’s Oo was last definitively recorded in 1904, although reports persisted for decades afterwards on its former island home of Molokai. As with other species in this piece, fossil remains indicate it may have been more widespread before the arrival of Polynesian settlers. In recent times, the range of these birds was much more restricted. The most recent notable sighting was in 1981. Given this species has not been unequivocally seen alive in over a century, it is surely lost now. Cattle ranching and pineapple cultivation have much altered Molokai, and introduced avian diseases are as problematic there as elsewhere.

Kauai’s Oo was the last survivor of the Mohoidae. Once common, it entered a steep decline during the early twentieth century. Again, habitat destruction and disease-bearing mosquitoes were the key culprits. In 1987, the mating song of a male Kauai Oo was recorded. Over untold millennia, his species had evolved a delicate call-and-response duet. But for Earth’s last Kauai Oo, there would be no answer. He died later that year.




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