Cyrtepistomus castaneus
In 3 days ~10% in a week ~20%
Cyrtepistomus castaneus, the Asiatic oak weevil, is a species of Asian broad-nosed weevil in the beetle family Curculionidae. It is native to Asia, and was first found in North America in 1933. Larvae feed on root hairs in soil, whereas adult beetles are defoliators of Quercus and Acer rubrum trees. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Great Smoky Mountains National Park | 🇺🇸 United States | |
| 2 | Shenandoah National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Boston | 🇺🇸 United States | |
| 2 | Washington | 🇺🇸 United States | |
| 3 | New York City | 🇺🇸 United States | |
| 4 | Baltimore | 🇺🇸 United States | |
| 5 | Toronto | 🇨🇦 Canada | |
| 6 | Philadelphia | 🇺🇸 United States | |
| 7 | Chicago | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report an Asian Oak Weevil sighting in Toronto on a given day, based on 40 verified sightings from GBIF citizen-science data. It is the 446th 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 20%, if each day is a fresh chance.
August
In that month about 10% of wildlife watchers report an Asian Oak Weevil in Toronto on a given day, against under 5% in September to July, the lowest months.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Asian Oak Weevil sightings with a recorded time, and about 7 in 10 of them come between 6 am and 6 pm: it is seen both by day and at night.
5th of 7
Of the 7 cities where we can rate Asian Oak Weevil sightings, Toronto ranks 5th at under 5%. The best odds are in Boston (United States, about 10%), Washington (United States, under 5%) and New York City (United States, under 5%).
Same family: Curculionidae
The closest relatives of the Asian Oak Weevil that you can see in Toronto (family Curculionidae, True Weevils) are Green Immigrant Leaf Weevil (about 10%), Black Vine Weevil (about 10%) and Sweetclover Weevil (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Asian Oak Weevil is recorded against all the insects logged in Toronto (40 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.
