Libellula pulchella
In 3 days ~30% in a week ~60%
The twelve-spotted skimmer (Libellula pulchella) is a common North American skimmer dragonfly, found in southern Canada and in all 48 of the contiguous U.S. states. It is a large species, at 50 mm (2.0 in) long. Each wing has three brown spots. In adult males, additional white spots form between the brown ones and at the bases of the hindwings; it is sometimes called the ten-spot skimmer for the number of these white spots. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Point Pelee National Park | 🇨🇦 Canada | |
| 2 | Acadia National Park | 🇺🇸 United States | |
| 3 | Yosemite National Park | 🇺🇸 United States | |
| 4 | Riding Mountain National Park | 🇨🇦 Canada | |
| 5 | Rocky Mountain National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 2 | Denver | 🇺🇸 United States | |
| 3 | Toronto | 🇨🇦 Canada | |
| 4 | Montreal | 🇨🇦 Canada | |
| 5 | Sacramento | 🇺🇸 United States | |
| 6 | Salt Lake City | 🇺🇸 United States | |
| 7 | Chicago | 🇺🇸 United States | |
| 8 | New York City | 🇺🇸 United States | |
| 9 | Detroit | 🇺🇸 United States | |
| 10 | Portland | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Twelve-Spotted Skimmer sighting in Denver on a given day, based on 186 verified sightings from GBIF citizen-science data. It is the 37th most-seen of the 461 insects we can rate there. Over three days the chance rises to about 30%, and over a week to about 60%, if each day is a fresh chance.
July and August
In those months about 20% of wildlife watchers report a Twelve-Spotted Skimmer in Denver on a given day, against under 5% in September to May, the lowest months. Those are among Denver's wettest months, with about 55 mm of rain a month against 15 mm in January.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Twelve-Spotted Skimmer sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 18 cities where we can rate Twelve-Spotted Skimmer sightings, Denver ranks 2nd at about 10%, level with the leaders once rounded. The best odds are in Minneapolis [Saint Paul] (United States, about 10%).
GBIF citizen-science records
It is estimated from how often the Twelve-Spotted Skimmer is recorded against all the insects logged in Denver (186 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.
