Alsophila pometaria
In 3 days ~10% in a week ~30%
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 Toronto on a given day, based on 121 verified sightings from GBIF citizen-science data. It is the 223rd most-seen of the 1689 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 30%, if each day is a fresh chance.
November
In that month about 20% of wildlife watchers report a Fall Cankerworm Moth in Toronto on a given day, against under 5% in January to October, the lowest months.
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.
3rd of 9
Of the 9 cities where we can rate Fall Cankerworm Moth sightings, Toronto ranks 3rd at under 5%. The best odds are in Minneapolis [Saint Paul] (United States, about 10%) and Edmonton (Canada, under 5%).
Same family: Geometridae
The closest relatives of the Fall Cankerworm Moth that you can see in Toronto (family Geometridae, Geometer Moths) are Chickweed Geometer Moth (about 10%), Pale Beauty (about 10%) and Single-Dotted Wave (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Fall Cankerworm Moth is recorded against all the insects logged in Toronto (121 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.
