The Red-naped Trogon (Harpactes kasumba) is a species of bird belonging to the Trogonidae family. The bird is mostly found in Brunei, Indonesia, Malaysia, and Thailand. Its natural habitat is subtropical or tropical moist lowland forests. Currently, Red-naped Trogon is threatened by habitat loss. The male red-naped trogon is actually defined by a black head and upper breast, blue bill, and an eye ring with a bright blue-colored face. The bird has yellow-brown upper parts and an upper tail with black outlines, a white breast line, bright red underparts, and the undertail is black and white.
The most defining physical characteristic of the red-naped trogon is a band of bright red feathers around the back of the head, which gives the species its name. The red-naped trogon is a sturdily sexually dimorphic species, with the females usually being duller than the males. Both males and females have a lifespan of approximately 7.3 years. The females are blander in color than the males, containing a grey-brown head and upper breast with yellow underparts.
Both the male and female grow in height up to 32 centimeters, or 12.5 inches. However, their legs and feet are short and feeble, which makes them inept at walking; in their place, they are limited to the occasional shuffle along a branch. The ratio of leg muscle to body weight in all Trogonidae species is only 3%, the lowest known ratio of any bird.
Moreover, the arrangement of the toes on Trogonidae species feet is very rare among birds and is arranged with the third and fourth toes projecting forward and the first and second toes projecting backward, an arrangement recognized as heterodactylous. Because of this arrangement, the red-naped trogon is unable to turn around on a branch if its wings are not aiding the movement.
Both sexes have compact bodies, short wings, and long tails. However, the wings are short, but they’re quite strong, with the wing muscle ratio being approximately 22% of the body weight. In spite of their strength of flight, red-naped trogons do not fly great distances, generally flying no more than a few hundred meters at a time.
The red-naped trogon’s singing voice is very sluggish, sad-sounding, and 5 to 8-note “pau pau pau pau pau.” Each short note was slightly down slurred (1.5–1.2 kHz) and delivered at a rate of c.1 note/s. Moreover, in addition to the territorial and breeding calls given by males and females during the breeding seasons, red-naped trogons have also been recorded as having aggression and alarm calls.
Red-naped trogons are usually inactive outside of their consistent feeding patterns. Because of this, birdwatchers and biologists have observed that, apart from their overall attractiveness, they’re infamous for their lack of other immediately engaging qualities.
Their lack of activity has been considered a defense against predation. Moreover, high rates of deforestation in the Sundaic lowlands have been very rapid, owing to the escalation of illegal logging and land conversion that targets all remaining stands of valuable timber.
In addition, forest fires have had a detrimental impact and have been another influence. Because of these threats, the red-naped trogon has been ranked by Birdlife as near-threatened species (NT). As with other Trogonidae species, red-naped trogons have been reported to shift along branches to retain their dull-colored backs turned towards observers, while their heads, which can rotate at 180 degrees similar to owls, are turned to keep watch on any possible predators. They’re preyed upon by hawks and predatory mammals.
Also Read: The Crested Kingfisher (Megaceryle lugubris)