Olivaceous Thornbill vs Amethyst-throated Mountain-gem
Chalcostigma olivaceum compared with Lampornis amethystinus
Side-by-Side Comparison
| Attribute | Olivaceous Thornbill | Amethyst-throated Mountain-gem |
|---|---|---|
| Scientific Name | Chalcostigma olivaceum | Lampornis amethystinus |
| Order | Caprimulgiformes | Caprimulgiformes |
| Family | Trochilidae | Trochilidae |
| Conservation Status | Least Concern | Least Concern |
| Length | — | — |
| Wingspan | 16.3 cm (6.4 in) | 13.1 cm (5.2 in) |
| Weight | 7.3999999999999995 g (0.26 oz) | 5.6000000000000005 g (0.20 oz) |
| Diet | Nectarivore of high Bolivian and Peruvian páramo; short bill accesses small open flowers. Gleans insects … | Nectarivore of Mexican and Central American montane pine-oak forest; visits Ericaceae and Salvia. Gleans arthropods. |
| Clutch Size | 2 | 2 |
| Population Trend | — | — |
Habitat Comparison
Shared Habitats
Olivaceous Thornbill only
Amethyst-throated Mountain-gem only
None
Song & Call Comparison
Olivaceous Thornbill
Buzzy, high-frequency trill with insect-like quality; sustained continuous vibration with rapid amplitude modulation.
Amethyst-throated Mountain-gem
Pure, sustained flute-like tone held steady; single clear note with barely perceptible vibrato in tropical shade.
Geographic Range & Migration
Olivaceous Thornbill
Widespread in high Andean puna grassland from Peru to Bolivia and northwestern Argentina. 3,200–4,800 m.
Amethyst-throated Mountain-gem
Found in montane forest from Mexico south through Guatemala and Honduras to El Salvador. 1,000–3,200 m.
Conservation Status
Olivaceous Thornbill
Amethyst-throated Mountain-gem
How to Tell Them Apart
Olivaceous Thornbill
Blue-tufted Starthroat: males with iridescent blue-green gorget; metallic green above; white pectoral tufts; females green above; spots
Amethyst-throated Mountain-gem
Bumblebee Hummingbird: tiny; males with brilliant violet gorget; metallic green above; white underparts; females green above; spotted
About These Birds
Olivaceous Thornbill
A small hummingbird (11-12 cm) found in Andean puna and páramo from Peru to Bolivia at 3,500-4,800 m. Olive-green plumage with subtle throat iridescence. Nectarivore of high-altitude flowering plants. One of the drabbest thornbills. Tolerates extreme cold.
Amethyst-throated Mountain-gem
A medium-sized hummingbird (11-12 cm) found in mountain forests from Mexico to Honduras at 1,000-3,000 m. Males have an amethyst-purple throat. Nectarivore of pine-oak and cloud forest. Commonly visits feeders in Mexican highland gardens.