Paleacrita vernata
In 3 days ~10% in a week ~20%
Paleacrita vernata, the spring cankerworm, is a moth of the family Geometridae. The species was first described by William Dandridge Peck in 1795. It is found in North America from the Atlantic Ocean west to Alberta, Texas and California.
The length of the forewings is 11–18 mm for males. The females are wingless. Adult males are on wing from February to late May. The larvae feed on various deciduous trees and shrubs, but especially Acer, Ulmus, Betula and Prunus species. Oaks (Quercus) are also affected, and many homeowners place sticky bands around trunks of their trees to trap the migrating adults as they climb the tree to lay eggs. The eggs hatch, turning into numerous inch-long worms that can defoliate and kill a tree. The worms often fall from the canopy onto passersby. Usually they are suspended by a line of silk that they can climb back into the tree along, should a spring wind dislodge them from their meal of leaves. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Austin | 🇺🇸 United States | |
| 2 | Dallas | 🇺🇸 United States | |
| 3 | Baltimore | 🇺🇸 United States | |
| 4 | Chicago | 🇺🇸 United States | |
| 5 | Boston | 🇺🇸 United States | |
| 6 | Washington | 🇺🇸 United States | |
| 7 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 8 | Toronto | 🇨🇦 Canada | |
| 9 | Montreal | 🇨🇦 Canada | |
| 10 | New York City | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a Spring Cankerworm Moth sighting in Montreal on a given day, based on 6 verified sightings from GBIF citizen-science data. It is the 749th most-seen of the 926 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.
Any time of year
In every month with enough records, under 5% of wildlife watchers report a Spring Cankerworm Moth in Montreal on a given day, so our monthly data shows no clear season.
9th of 10
Of the 10 cities where we can rate Spring Cankerworm Moth sightings, Montreal ranks 9th at under 5%. The best odds are in Austin (United States, about 10%), Dallas (United States, about 10%) and Baltimore (United States, under 5%).
Same family: Geometridae
The closest relatives of the Spring Cankerworm Moth that you can see in Montreal (family Geometridae, Geometer Moths) are Lesser Maple Spanworm Moth (about 10%), Pale Beauty (about 10%) and Chickweed Geometer Moth (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Spring Cankerworm Moth is recorded against all the insects logged in Montreal (6 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.
