Melanerpes formicivorus
Silhouette: Edwin Price · PhyloPic
In 3 days ~10% in a week ~30%
The acorn woodpecker (Melanerpes formicivorus) is a medium-sized woodpecker with a length of around 20 cm (8 in), and an average weight of 85 g (3.0 oz). It is found across Central America, as well as North into the western United States and South into parts of Colombia.
The acorn woodpecker was formally described in 1827 by the English naturalist William Swainson under the binomial name Picus formicivorus from a specimen collected in Mexico. The specific epithet combines the Latin formica meaning "ant" with -vorus meaning "eating". The type locality is Temascaltepec in Mexico. The acorn woodpecker is one of 24 species now placed in the genus Melanerpes that was introduced by Swainson in 1832. Within Melanerpes the acorn woodpecker is sister to a clade containing two South American species: the white woodpecker (Melanerpes candidus) and the white-fronted woodpecker (Melanerpes cactorum).
Seven subspecies are recognised: Wikipedia →
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Sacramento | 🇺🇸 United States | |
| 2 | Guatemala City | 🇬🇹 Guatemala | |
| 3 | Los Angeles | 🇺🇸 United States | |
| 4 | Medellín | 🇨🇴 Colombia | |
| 5 | San Francisco | 🇺🇸 United States | |
| 6 | Tegucigalpa | 🇭🇳 Honduras | |
| 7 | Mesa | 🇺🇸 United States | |
| 8 | Phoenix | 🇺🇸 United States | |
| 9 | Guadalajara | 🇲🇽 México | |
| 10 | San Diego | 🇺🇸 United States |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Lindsay Wildlife Experience | 🇺🇸 United States | |
| 2 | California Wildlife Center, Malibu | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report an Acorn Woodpecker sighting in Poás Volcano National Park on a given day, based on 144 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 108th most-seen of the 356 birds 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.
May–September and November
In those months about 10% of wildlife watchers report an Acorn Woodpecker in Poás Volcano National Park on a given day, against under 5% in October and December–April, the lowest months.
Between 8 and 11 am
Across all the parks we cover, that three-hour window holds the most Acorn Woodpecker sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
19th of 26
Of the 26 parks where we can rate Acorn Woodpecker sightings, Poás Volcano National Park ranks 19th at under 5%. The best odds are in Irazú Volcano National Park (Costa Rica, about 70%), Los Quetzales National Park (Costa Rica, about 70%) and Celaque National Park (Honduras, about 60%). All parks ranked.
GBIF citizen-science records
It is estimated from how often the Acorn Woodpecker is recorded against all the birds logged in Poás Volcano National Park (144 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.
