Syrigma sibilatrix
Silhouette: Sheatherius · PhyloPic
In 3 days ~20% in a week ~40%
The whistling heron (Syrigma sibilatrix) is a medium-sized, often terrestrial heron of South America. It is the only species placed in the genus Syrigma. A molecular phylogenetic study published in 2023 found that within the heron family the whistling heron is most closely related to the capped heron (Pilherodius pileatus).
The whistling heron measures 53 to 64 cm in length and weighs 521 to 546 g. The southern subspecies is bigger but has a shorter bill in proportion to the body. The overall impression of standing birds is gray, with flying birds showing conspicuous white rear parts (lower back, belly, and tail). In both subspecies, adults' upperparts except the lower back are blue-gray. The feathers of the sides of head, sides of the neck, breast, and scapular area are basically white but are stained gold to buff, perhaps by the powder down typical of herons... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Emas National Park | 🇧🇷 Brazil | |
| 2 | Iberá National Park | 🇦🇷 Argentina | |
| 3 | Sierra de la Macarena National Park | 🇨🇴 Colombia | |
| 4 | El Palmar National Park | 🇦🇷 Argentina | |
| 5 | El Impenetrable National Park | 🇦🇷 Argentina | |
| 6 | Parque Estadual Encontro das Águas | 🇧🇷 Brazil | |
| 7 | Serra da Canastra National Park | 🇧🇷 Brazil | |
| 8 | Henri Pittier National Park | 🇻🇪 Venezuela | |
| 9 | Chingaza National Natural Park | 🇨🇴 Colombia | |
| 10 | Iguaçu National Park | 🇧🇷 Brazil | |
| 11 | Iguazú National Park | 🇦🇷 Argentina | |
| 12 | Serra dos Órgãos National Park | 🇧🇷 Brazil | |
| 13 | Chapada dos Guimarães National Park | 🇧🇷 Brazil | |
| 14 | Itatiaia National Park | 🇧🇷 Brazil | |
| 15 | Tijuca National Park | 🇧🇷 Brazil | |
| 16 | Yasuní National Park | 🇪🇨 Ecuador |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Santa Cruz de la Sierra | 🇧🇴 Bolivia | |
| 2 | Campo Grande | 🇧🇷 Brazil | |
| 3 | Asuncion | 🇵🇾 Paraguay | |
| 4 | Rosario | 🇦🇷 Argentina | |
| 5 | Porto Alegre | 🇧🇷 Brazil | |
| 6 | Caracas | 🇻🇪 Venezuela | |
| 7 | Buenos Aires | 🇦🇷 Argentina | |
| 8 | Curitiba | 🇧🇷 Brazil | |
| 9 | Cordoba | 🇦🇷 Argentina | |
| 10 | Goiânia | 🇧🇷 Brazil |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Parque das Aves | 🇧🇷 Brazil | |
| 2 | Temaikén | 🇦🇷 Argentina | |
| 3 | GüiráOga | 🇦🇷 Argentina |
With luck
About 10% of wildlife watchers report a Whistling Heron sighting in Porto Alegre on a given day, based on 157 verified sightings from GBIF citizen-science data. It is the 73rd most-seen of the 159 birds we can rate there. Over three days the chance rises to about 20%, and over a week to about 40%, if each day is a fresh chance.
March–July and September–January
In those months about 10% of wildlife watchers report a Whistling Heron in Porto Alegre on a given day, against under 5% in February and August, the lowest months.
Between 8 and 11 am
Across all the parks we cover, that three-hour window holds the most Whistling Heron sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
5th of 19
Of the 19 cities where we can rate Whistling Heron sightings, Porto Alegre ranks 5th at about 10%. The best odds are in Santa Cruz de la Sierra (Bolivia, about 30%), Campo Grande (Brazil, about 10%) and Asuncion (Paraguay, about 10%).
Same family: Ardeidae
The closest relatives of the Whistling Heron that you can see in Porto Alegre (family Ardeidae, Herons, Egrets, and Bitterns) are Great Egret (about 20%), Black-crowned Night Heron (about 20%) and Snowy Egret (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Whistling Heron is recorded against all the birds logged in Porto Alegre (157 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.
