Acronicta betulae
In 3 days ~10%
Acronicta betulae, commonly known as the birch dagger moth, is a moth of the family Noctuidae. It is found from New Hampshire to Florida, west to Texas, north to Wisconsin. The wingspan is 35–40 mm (1.4–1.6 in). Adults are on wing from March to May and from August to September in two generations.
The larvae feed on the leaves of birch, possibly exclusively Betula nigra. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Washington | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a River Birch Dagger sighting in Washington on a given day, based on 8 verified sightings from GBIF citizen-science data. It is the 1330th most-seen of the 1807 insects we can rate there. Over three days the chance rises to about 10%, if each day is a fresh chance.
Any time of year
In every month with enough records, under 5% of wildlife watchers report a River Birch Dagger in Washington on a given day, so our monthly data shows no clear season.
Only Washington, in our data
Washington is the only city on Wallace's Line with enough records to rate River Birch Dagger sightings: under 5% of wildlife watchers there report one on a given day.
Same genus: Acronicta
The closest relatives of the River Birch Dagger that you can see in Washington (genus Acronicta, Dagger Moths) are American Dagger (about 10%) and Smeared Dagger (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the River Birch Dagger is recorded against all the insects logged in Washington (8 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.
