Aeorestes cinereus
Silhouette: Andy Wilson · PhyloPic
In 3 days ~10% in a week ~20%
The hoary bat (Lasiurus cinereus) is a species of bat in the vesper bat family, Vespertilionidae. It lives throughout most of North America (and possibly also in Hawaii, although this is disputed). The hoary bat was described as a new species in 1796 by Palisot de Beauvois. Mammalogist Harrison Allen was the first to use its current name combination of Lasiurus cinereus, doing so in 1864. In a later publication, Allen placed it in the now-defunct genus Atalapha, with a scientific name of Atalpha cinerea.
The South American hoary bat (L. villosissimus), which is found throughout South America, and the Hawaiian hoary bat (L. semotus), which is endemic to Hawaii, were both previously classified under the hoary bat, but phylogenetic evidence supports them being distinct species.
Some have argued to elevate the subgenus (Aeorestes) to a genus level classification for L. cinereus. However, this has not been accepted by taxonomic authorities... Wikipedia →
Echolocation0:07
United States · 2026
© John Rommereim · XC1100677 · CC BY-NC-SA 4.0
| # | Park | Country | Daily sighting probability |
|---|
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Mexico City | 🇲🇽 México | |
| 2 | Austin | 🇺🇸 United States | |
| 3 | Los Angeles | 🇺🇸 United States | |
| 4 | Chicago | 🇺🇸 United States | |
| 5 | New York City | 🇺🇸 United States | |
| 6 | San Francisco | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a Hoary Bat sighting in Chicago on a given day, based on 6 verified sightings from GBIF citizen-science data. It is the 26th most-seen of the 26 mammals 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.
Any time of year
In every month with enough records, under 5% of wildlife watchers report a Hoary Bat in Chicago on a given day, so our monthly data shows no clear season.
Between 8 and 11 pm
Across all the parks we cover, that three-hour window holds the most Hoary Bat sightings with a recorded time, and about 6 in 10 of them come between 6 am and 6 pm: it is seen both by day and at night.
Among the best
Of the 6 cities where we can rate Hoary Bat sightings, Chicago ranks 4th at under 5%, level with the leaders once rounded. The best odds are in Mexico City (México, under 5%), Austin (United States, under 5%) and Los Angeles (United States, under 5%).
Same family: Vespertilionidae
The closest relatives of the Hoary Bat that you can see in Chicago (family Vespertilionidae, Evening Bats) are Silver-haired Bat (about 10%) and Eastern Red Bat (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Hoary Bat is recorded against all the mammals logged in Chicago (6 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.
