Arremon semitorquatus
Silhouette: Juan Camilo Cepeda-Duque · PhyloPic
In 3 days ~10% in a week ~20%
The half-collared sparrow (Arremon semitorquatus) is a species of bird in the family Passerellidae, the New World sparrows. It is endemic to Brazil. The half-collared sparrow was formally described in 1838 with its current binomial Arremon semitorquatus. It was long treated as a subspecies of the pectoral sparrow (A. taciturnus) but was again elevated to full species status in the early 2000s. The two are sister species.
The half-collared sparrow is monotypic. The half-collared sparrow is about 15 cm (5.9 in) long and weighs 22 to 28 g (0.78 to 0.99 oz). The species is sexually dimorphic but not dramatically so. Adult males have a black crown with a gray stripe through its middle, black lores, and a white supercilium that extends to the nape. The rest of their face is black. Their nape and the sides of their neck are gray. Their upperparts, wings, and tail are mostly greenish olive with somewhat more yellowish green on the lesser wing coverts. They have a white throat. Their underparts are mostly white with a black patch on the side of the upper breast and gray flanks. Adult females have a similar pattern to males. Female's upperparts... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Itatiaia National Park | 🇧🇷 Brazil | |
| 2 | Serra dos Órgãos National Park | 🇧🇷 Brazil |
Rare
Under 5% of wildlife watchers report a Half-collared Sparrow sighting in Serra dos Órgãos National Park on a given day, based on 29 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 231st most-seen of the 336 birds we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
October to December
In those months about 10% of wildlife watchers report a Half-collared Sparrow in Serra dos Órgãos National Park on a given day, against under 5% in January to September, the lowest months. Those are among Serra dos Órgãos National Park's wettest months, with about 260 mm of rain a month against 50 mm in July.
Between 7 and 10 am
Across all the parks we cover, that three-hour window holds the most Half-collared Sparrow sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
2nd of 2
Of the 2 parks where we can rate Half-collared Sparrow sightings, Serra dos Órgãos National Park ranks 2nd at under 5%. The best odds are in Itatiaia National Park (Brazil, about 10%).
GBIF citizen-science records
It is estimated from how often the Half-collared Sparrow is recorded against all the birds logged in Serra dos Órgãos National Park (29 verified sightings from 2019 to 2026), 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.
