​The show birds of New Guinea

Text: Chris Lyngaas, Rainforest Foundation Norway

We are at ground level in the rainforest. The small jet-black bird makes a painstaking effort to remove leaves and other stray objects with its beak. The show is almost ready to begin and the stage must be perfect.

Sole male lead: a male of the species Western Parotia (Parotia sefilata).

Sole spectator to this performance: a female bird who has secured a perch on the best branch in the house.

Merciless flirting

There is no Oscar for Best Performance awaiting the male but rather something more important – permission to mate and pass on its genes. It is not an easy job. The females are extremely fussy and as a rule the male ends up being rejected. One little mistake in the performance and the show is over.

Flirting Bird-of-paradise style is merciless.

Showdance of the bird world

The male bird does not seem to be concerned about the chances of rejection. It starts confidently with a gallant bow and a quick change in eye colour from blue to yellow. A little foretaste of things to come.

As the bird straightens up, it spreads out its feathers so that it resembles an open umbrella. Now the dance can begin. On its head, the male bird has six long, thread-like head feathers with a small black circle on each tip. The cocky little suitor begins to shake its head so that the circles vibrate with rhythmic elegance. It takes a few quick steps to the right and then to the left. There is an artistic pause. It seems to be working. The female bird is still watching. The bird world’s answer to John Travolta has only just begun.

An optical illusion

The dancing and the posing are not inborn. The bird has learned these from its father and practiced for a long time to perfect the performance. It is all about creating a seductive optical illusion. The spectacle can best be seen from above, where the female is perched on the best branch in the house.

The male bird stands with its legs wide apart, swaying its breast from side to side in a wave-like movement. From above, you can see a large black hole and some smaller black ‘moons’ that move backwards and forwards over the brown earth. The effect is hypnotic. Then it reaches the climax. There is a sudden flash of brilliant iridescent yellow and blue in the black hole. The male bird provides a seductive glimpse of the colourful plumage that is hidden beneath the black surface.

The female has been won over and the male does not wait to be asked twice. He accepts his accolade on the best branch in the house.

Sexual selection

He is fortunate. These performances can go on for hours before the female is satisfied – or flies away. The ladies, who are for their part quite ordinary looking, choose only the males with the most beautiful plumage, the most impressive poses and the most precise dance movements. It is one of nature’s most obvious examples of sexual selection, in which the individuals that are most attractive to partners of the opposite sex get to mate the most. According to Darwin’s Theory of Evolution, the traits that ensure survival of the species are passed on to the next generation. Birds-of-paradise have few natural enemies and easy access to food. Therefore, sexual selection and the contest for the females’ favour are the most important factors if a male bird wants to pass on its genes. And that is exactly what it wants.

Occasionally genes get shuffled around, mutating when they are passed on and resulting in new traits. A bird might be born with longer, more colourful feathers than is usual. For some reason, females prefer these traits and choose to mate with the males that have the most impressive plumage. Their young inherit both the father’s colourful plumage and the mother’s preferences for that trait. In this way, evolution has ensured that these birds are considered to be the most beautiful and remarkable creatures in the animal kingdom.

Diverse bird family

The Bird-of-paradise (Paradisaeidae) family is quite a clan. These song birds belong to the same order as sparrows, and there are 42 different species with distinctive names like the Magnificent Riflebird, the Vogelkop Superb and Wilson’s Bird-of-Paradise. They vary greatly in size, usually between 15–44 cm long excluding the tail and head feathers. The plumage can, however, add a few extra centimetres to their length. Their diet consists primarily of fruit and small arthropods. There is a great diversity of shapes and colours, but common to all of them is the male’s unique plumage and their distinctive mating rituals. Their feathers are popular as adornments for the indigenous people on the island and were once the height of fashion in European women’s headwear.

Kangaroos that climb trees and butterflies the size of birds

With the exception of a few species that live in rainforests in northern Australia and the Maluku Islands, birds-of-paradise are indigenous to the island of New Guinea. This is the second largest island in the world and one of the last great contiguous rainforest areas left. Rainforest covers 65 % of the island, which has a rich and unique flora and fauna. Up to 10 % of the world’s land-based species live on just 0.5 % of the earth’s land mass.

In New Guinea, one can find kangaroos that climb trees, butterflies the size of birds and more species of orchids than anywhere else on earth. The island has very few predators, which has allowed the birds-of-paradise to evolve in peace.

Diversity also extends to the indigenous peoples of the island. New Guinea is a paradise for social anthropologists and linguists. Over 1 000 individual languages are spoken here and it is estimated that there are just as many different ethnic groups.

Paradise under pressure

Birds-of-paradise live in inaccessible and isolated areas featuring dense forest, deep valleys and steep mountains. This has allowed them to live a relatively undisturbed existence, and there still remains much that is undiscovered and unknown hidden in the rainforest. Birds-of-paradise have an almost mythological status among ornithologists and to actually see one is a momentous occasion. They are so iconic that they are represented on the national flag of Papua New Guinea, which covers the eastern half of the island. The western part of the island consists of the Indonesian provinces of Papua and West Papua.

However, birds-of-paradise are not out of harm’s way. Logging, mining and oil palm plantations threaten the rainforests in New Guinea.

If birds-of-paradise are to continue seducing and being seduced, the rainforest must be protected.