Queen Alexandra's birdwing

This butterfly lives in only one small place in the world.

It lives in a warm, wet rainforest in Papua New Guinea. It flies high above the treetops.

Queen Alexandra's birdwing lives only on the island of New Guinea, and all its known homes are in a small part of southeastern Papua New Guinea, around the Popondetta Plain north of the Owen Stanley mountains.

It lives in lowland rainforest, both old forest and forest that has grown back, and in some lower mountain forest up to about 850 meters high. Scientists know of only four groups, or subpopulations, and maybe a fifth. Together they occupy an area of less than 140 square kilometers.

The species is endemic to New Guinea, with all current records from southeastern Papua New Guinea north of the Owen Stanley Range: the Popondetta Plains and the Afore area on the Managalase Plateau. The IUCN recognizes four confirmed subpopulations (Cape Ward Hunt, Popondetta, Sibium Mountains and Upper Musa Valley), with a possible fifth.

It occupies primary and advanced secondary lowland rainforest, mostly below 200 meters, and lower montane secondary forest up to about 850 meters. The extent of occurrence is about 8,710 square kilometers including uncertain records, or 2,800 using only certain ones, and the area of occupancy is under 140 square kilometers. It is absent from some areas where its food plants are common, possibly because it favors lighter forest and avoids thorny thickets.

The caterpillars eat the leaves of special vines called pipevines.

The grown-up butterflies sip sweet nectar from flowers, high in the trees and in gardens.

Queen Alexandra's birdwing caterpillars eat only the leaves of certain pipevines, climbing vines that grow up into the rainforest trees. The mother lays her eggs on these vines, so where the vines disappear, the butterflies cannot survive.

Grown-up butterflies drink nectar from flowers. They often fly high above the forest, probably searching for flowers on rainforest trees. Females are also often seen at flowers in gardens and farms, such as hibiscus and coffee trees.

Larvae feed on vines of the pipevine family (Aristolochiaceae). The species was once thought to use only Aristolochia dielsiana, but Pararistolochia alexandriana and P. meridionaliana are now also known host plants, and larvae accepted A. tagala in experiments. Habitat conversion that removes these vines is a direct cause of decline.

Adults generally fly high above the canopy, presumably seeking the flowers of rainforest trees. Females are most often observed at introduced ornamentals such as Spathodea and Hibiscus, and at coffee trees; males have been reported feeding at Deplanchea and kwila (Intsia bijuga) trees (IUCN, citing Parsons 1999).

Birdwings are strong fliers.

They glide and flap high above the tall rainforest trees. It can be hard to spot them from the ground!

Grown-up birdwings are strong fliers that travel widely and usually fly high above the rainforest canopy, the leafy roof of the forest. That makes them hard to count. In one survey, more than 80 adult males and 80 adult females were recorded, but scientists think many butterflies were counted more than once.

Counting the young is more reliable. In a 50-day survey with about five people searching each day, only 23 caterpillars were found.

Adults are large, strong, wide-ranging fliers that usually stay above the canopy, so adult counts are easily inflated: a 10-day Managalase survey by 28 observers logged 82 adult males and 85 adult females but only seven larvae and one pupa, and the adult figures are considered over-representations. A 50-day survey with an average of five observers found only 23 larvae across the Popondetta Plain and Afore area.

Predation on adults is low, though kingfishers and large orb-web spiders have been reported to take them. Where host vines are abundant, the species can be locally occasional to common, around 2 to 10 individuals seen over 10 days (Parsons 1999).

Queen Alexandra's birdwing is endangered.

Many of its forest homes have been cut down to grow crops. It is against the law to catch it or sell it. People are working to keep its forests safe.

Queen Alexandra's birdwing is endangered. Its biggest problem is losing its rainforest home, which has been cleared for logging and for plantations of rubber, cocoa and especially oil palm. A volcanic eruption of Mount Lamington in 1951 also destroyed a large part of its habitat.

It has been protected by law in Papua New Guinea since 1966, and since 1987 international trade in it has been banned except for science. Collectors once paid as much as $2,850 for a single damaged specimen, but the IUCN names habitat destruction as the main threat today.

The IUCN assessed O. alexandrae as Endangered under criterion B2ab(iii) on 24 January 2018 (published 2018; Endangered in every assessment since 1983), because of its tiny area of occupancy, a maximum of five locations, and continuing habitat loss. The main threat is conversion of forest to plantations, especially oil palm: FAO figures cited in the assessment show oil palm area in Papua New Guinea rising by 72.3 percent from 1989 to 2013. The American Museum of Natural History adds habitat loss from the 1951 eruption of Mount Lamington.

It has been protected under Papua New Guinea's Fauna Protection Ordinance since 1966 and listed on CITES Appendix I since 1987. Conservation ideas include special reserves, payments that reward local people for keeping forest, and butterfly farming as an alternative income to oil palm, although trade in this species remains prohibited except for science.