Aeshna umbrosa
In 3 days ~10% in a week ~20%
The shadow darner (Aeshna umbrosa) is a species of dragonfly in the family Aeshnidae. It is found in almost all of Canada and most states in the United States. The shadow darner is a large dragonfly with a length of 68 to 78 mm (2.7 to 3.1 in). The base is brownish black in color. Greenish crescent-shaped spots are found at the top of the thorax. The sides of the thorax are marked with two yellowish to yellowish-green diagonal stripes. Its abdomen is marked with bluish green spots. The male shadow darner has paddle-shaped anal appendages.
The naiad of the shadow darner is large in size, with a length of 38 to 43 mm (1.5 to 1.7 in). This naiad is long and slender, which is the typical shape of immature darners. It is mottled green and brown. The shadow darner has a vertically flattened cerci with a spike at the end.
This dragonfly is found in most of the United States except the dry Southwest and in all of the provinces and territories of Canada. The shadow darner patrols along small marshy streams. It is often found feeding along woodland edges or even in deep shadow in full forest. Shadow darners can also be found near... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Gros Morne National Park | 🇨🇦 Canada | |
| 2 | Yosemite National Park | 🇺🇸 United States | |
| 3 | Acadia National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Toronto | 🇨🇦 Canada | |
| 2 | Portland | 🇺🇸 United States | |
| 3 | Montreal | 🇨🇦 Canada | |
| 4 | Seattle | 🇺🇸 United States | |
| 5 | Denver | 🇺🇸 United States | |
| 6 | Vancouver | 🇨🇦 Canada | |
| 7 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 8 | Boston | 🇺🇸 United States | |
| 9 | Edmonton | 🇨🇦 Canada | |
| 10 | Baltimore | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a Shadow Darner sighting in Boston on a given day, based on 15 verified sightings from GBIF citizen-science data. It is the 583rd most-seen of the 1200 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.
September and October
In those months about 10% of wildlife watchers report a Shadow Darner in Boston on a given day, against under 5% in November to August, the lowest months.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Shadow Darner sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
8th of 12
Of the 12 cities where we can rate Shadow Darner sightings, Boston ranks 8th at under 5%. The best odds are in Toronto (Canada, about 10%), Portland (United States, about 10%) and Montreal (Canada, under 5%).
GBIF citizen-science records
It is estimated from how often the Shadow Darner is recorded against all the insects logged in Boston (15 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.
