Alsophila pometaria
In 3 days ~10% in a week ~20%
Alsophila pometaria, the fall cankerworm, is a moth of the family Geometridae. It is found in North America from Nova Scotia west to Alberta, south to Colorado and California. The caterpillars grow to about 25 mm long. In color, they vary from light green to a dark brownish green. Light green caterpillars have white lines running down the body from the head to the tip of the abdomen while the darker caterpillars have a black stripe the length of their back. Larvae have three pairs of legs on their thorax and three pairs of prolegs on their abdomen. The first pair of prolegs (on segment 8, unexpected in Geometridae as opposed to Noctuidae) is much smaller than the last two pairs (the one on segment 9 typical for geometer moths and the pygopodium at the end of the animal). The pupa is wrapped in a silk cocoon and is buried just beneath the surface of the ground.
Adult males have a 25–35 mm wingspan. The forewings are glossy brown and crossed with irregular white bands. The females are brownish gray, wingless, and 10–12 mm long. Eggs are grayish brown with a dot and ring on the top and are less than 1 mm in diameter.
The larvae feed on a large variety of... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Shenandoah National Park | 🇺🇸 United States |
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 2 | Edmonton | 🇨🇦 Canada | |
| 3 | Toronto | 🇨🇦 Canada | |
| 4 | Boston | 🇺🇸 United States | |
| 5 | Calgary | 🇨🇦 Canada | |
| 6 | Philadelphia | 🇺🇸 United States | |
| 7 | Denver | 🇺🇸 United States | |
| 8 | New York City | 🇺🇸 United States | |
| 9 | Washington | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a Fall Cankerworm Moth sighting in Denver on a given day, based on 7 verified sightings from GBIF citizen-science data. It is the 352nd most-seen of the 461 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.
November
In that month about 10% of wildlife watchers report a Fall Cankerworm Moth in Denver on a given day, against under 5% in December to October, the lowest months. That is one of Denver's driest months, with about 20 mm of rain against 60 mm in July.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Fall Cankerworm Moth sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
7th of 9
Of the 9 cities where we can rate Fall Cankerworm Moth sightings, Denver ranks 7th at under 5%. The best odds are in Minneapolis [Saint Paul] (United States, about 10%), Edmonton (Canada, under 5%) and Toronto (Canada, under 5%).
GBIF citizen-science records
It is estimated from how often the Fall Cankerworm Moth is recorded against all the insects logged in Denver (7 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.
