Libellula forensis
In 3 days ~30% in a week ~60%
The eight-spotted skimmer (Libellula forensis) is a dragonfly of the skimmer family. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Redwood National Park | 🇺🇸 United States | |
| 2 | Olympic National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Seattle | 🇺🇸 United States | |
| 2 | Portland | 🇺🇸 United States | |
| 3 | Vancouver | 🇨🇦 Canada | |
| 4 | Salt Lake City | 🇺🇸 United States | |
| 5 | Denver | 🇺🇸 United States | |
| 6 | San Francisco | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report an Eight-Spotted Skimmer sighting in Portland on a given day, based on 270 verified sightings from GBIF citizen-science data. It is the 27th most-seen of the 507 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
In that month about 30% of wildlife watchers report an Eight-Spotted Skimmer in Portland on a given day, against under 5% in October to April, the lowest months. That is one of Portland's driest months, with about 10 mm of rain against 250 mm in December.
Between 1 and 4 pm
Across all the parks we cover, that three-hour window holds the most Eight-Spotted Skimmer sightings with a recorded time, and about 7 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
2nd of 6
Of the 6 cities where we can rate Eight-Spotted Skimmer sightings, Portland ranks 2nd at about 10%. The best odds are in Seattle (United States, about 20%).
Same genus: Libellula
The closest relatives of the Eight-Spotted Skimmer that you can see in Portland (genus Libellula, Chasers and King Skimmers) are Flame Skimmer (about 10%), Widow Skimmer (about 10%) and Twelve-Spotted Skimmer (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Eight-Spotted Skimmer is recorded against all the insects logged in Portland (270 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.
