Harpactes diardii (Temminck, 1832)

Taxonomy and Basic Classification

Diard's trogon (Harpactes diardii (Temminck, 1832)) is a medium-sized bird.

Size Measurements

It measures approximately 34 cm (13.4 in) in length and weighs about 100 g.

General Body Features

Like other trogons, it has hunched shoulders, a long tail, and vibrant plumage with a striking mix of contrasting colors.

Sexual Size and Plumage Difference Overview

Males and females are similar in size but have different plumage.

Shared Bill Morphology

Both sexes have a blue bill with a black tip.

Adult Male Head and Breast Plumage

Adult males have a black head and upper breast, paired with a purplish-blue eye ring.

Adult Male Crown and Collar Plumage

A maroon wash covers the mid-crown to the hind-crown, while the hind collar and breastline are pink.

Adult Male Belly and Upperpart Plumage

The male's belly and vent are bright red, and its upperparts and uppertail are pale brown.

Adult Male Undertail Markings

Blackish markings on the male's undertail give it a grayish-white appearance.

Adult Female Head and Upper Breast Plumage

Adult females have plumage in more earthy, softer hues, with a muted brownish head and upper breast.

Adult Female Lower Underpart Plumage

Their lower underparts are a brighter pinkish-red than the male's.

Juvenile Plumage

Juvenile Diard's trogons resemble females.

Primary Habitat Layers

This species is primarily found in the middle and lower layers of primary and logged forests in lowland and hilly regions.

Elevation Range in Malaysia and Thailand

It occurs up to 900 m elevation in Peninsular Malaysia, and is rarely found above 600 m in Thailand.

Habitat in Brunei and Sumatra

It also lives in peat swamp forests in Brunei and Sumatra, showing it can adapt to diverse habitats.

Borneo Habitat Types

In Borneo, it occupies a range of environments including lowland, upland, and highland dipterocarp forests, logged dipterocarp areas, streamside vegetation, and kerangas, a type of nutrient-poor heath forest.

Modified Habitat Use and Elevation

It can also be found in cocoa plantations near secondary forest areas, typically up to 1200 m elevation, though it is most often found at much lower altitudes.

Geographic Distribution

Its distribution covers the Thai peninsula, Peninsular Malaysia, the Indonesian and Malaysian parts of Borneo, and Bangka Island, which lies east of Sumatra in Indonesia.

Nest Construction

For reproduction, Diard's trogon excavates its nest in an old or dead tree trunk, usually at a height between 1 m and 3 m.

Breeding Season Timing

The breeding season runs from February to mid-May in Peninsular Malaysia, and from mid-May to August (sometimes extending into September) in Borneo.

Breeding Condition Observations

Some individuals have been observed in breeding condition during February and April.