Troides aeacus
In 3 days ~10% in a week ~30%
Troides aeacus, the golden birdwing, is a large tropical butterfly belonging to the swallowtail family, Papilionidae. Troides aeacus has a wingspan of about 150–170 millimetres (5.9–6.7 in) but can be as large as 194 mm. In the males the forewings are black, with veins bordered by a whitish colour, while the hindwings are bright yellow. The underside of the wings is quite similar to the upside. The females are larger than the males and have dark-brown or black wings. The head, thorax and abdomen of this butterfly are mainly black, with small red patches on the thorax and a yellow underside of the abdomen. Caterpillars are pale brown, with long protrusions resembling thorns. They mainly feed on Aristolochia and Thottea species (Aristolochiaceae).
Troides aeacus closely resembles Troides helena cerebrus and differs as follows: Upperside, forewing: the pale adnervular streaks more prominent, in some specimens extended into the cell along the outer half of the subcostal and of the median nervules.
Hindwing: the cone-shaped terminal black markings in interspaces 2, 3, and 4 more or less broadly bordered on the inner side by a dusky area that is irrorated with blackish... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Cuc Phuong National Park | 🇻🇳 Vietnam | |
| 2 | Cat Tien National Park | 🇻🇳 Vietnam | |
| 3 | Khao Yai National Park | 🇹🇭 Thailand | |
| 4 | Kaeng Krachan National Park | 🇹🇭 Thailand | |
| 5 | Taroko National Park | 🇹🇼 Taiwan |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Phnom Penh | 🇰🇭 Cambodia | |
| 2 | Guwahati | 🇮🇳 India | |
| 3 | Ho Chi Minh City | 🇻🇳 Vietnam | |
| 4 | Bangkok | 🇹🇭 Thailand | |
| 5 | Kuala Lumpur | 🇲🇾 Malaysia | |
| 6 | Hong Kong | 🇨🇳 China | |
| 7 | Singapore | 🇸🇬 Singapore |
Rare
Under 5% of wildlife watchers report a Golden Birdwing sighting in Hong Kong on a given day, based on 19 verified sightings from GBIF citizen-science data. It is the 488th most-seen of the 1125 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 30%, if each day is a fresh chance.
July and August
In those months about 10% of wildlife watchers report a Golden Birdwing in Hong Kong on a given day, against under 5% in September to June, the lowest months. Those are among Hong Kong's wettest months, with about 200 mm of rain a month against 25 mm in December.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Golden Birdwing sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
6th of 7
Of the 7 cities where we can rate Golden Birdwing sightings, Hong Kong ranks 6th at under 5%. The best odds are in Phnom Penh (Cambodia, about 20%), Guwahati (India, about 10%) and Ho Chi Minh City (Vietnam, about 10%).
GBIF citizen-science records
It is estimated from how often the Golden Birdwing is recorded against all the insects logged in Hong Kong (19 verified sightings), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
