Lasius brunneus
In 3 days ~10% in a week ~20%
Lasius brunneus is a species of ant in the genus Lasius. The species is widely distributed in Europe, from Sweden in the north to Anatolia in the south. In England this species is almost always found nesting in oak trees or rotting wood mainly foraging in trees but has also been found under stones and foraging on the ground. It is thought to be underrecorded but is fairly common especially in the South East.
Workers are easy to identify as they are bicoloured, but they can be confused with Lasius emarginatus. Nuptial flights have been recorded as early as May on warm days from early morning to early afternoon. Queens are smaller than other Lasius species, mainly a uniform dark brown colour with a flattish, slim appearance. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Pyrénées National Park | 🇫🇷 France |
More parks will be added in future updates.
Rare
Under 5% of wildlife watchers report a Brown Tree Ant sighting in Pyrénées National Park on a given day, based on 6 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 1144th most-seen of the 1277 insects 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.
February, April, October and December
In those months about 10% of wildlife watchers report a Brown Tree Ant in Pyrénées National Park on a given day, against under 5% in January, March, May–September and November, the lowest months.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Brown Tree Ant sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Only Pyrénées National Park, in our data
Pyrénées National Park is the only park on Wallace's Line with enough records to rate Brown Tree Ant sightings: under 5% of wildlife watchers there report one on a given day.
Same genus: Lasius
The closest relatives of the Brown Tree Ant that you can see in Pyrénées National Park (genus Lasius, Citronella Ants, Fuzzy Ants, and Allies) are Jet Ant (about 10%) and Central European Bicolored Ant (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Brown Tree Ant is recorded against all the insects logged in Pyrénées National Park (6 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.
