Aethalura punctulata
In 3 days ~10% in a week ~20%
Aethalura punctulata, the grey birch, is a moth of the family Geometridae. The species is found in Europe and then east, as far as western Siberia and the Caucasus.This species prefers sparse alder-ash-floodplain forests on moist to wet locations. Although it is only locally distributed in Central Europe, it is usually common in these biotopes. It occurs from the plains to the middle mountain regions. In the Alps it rises up to 1600 m.
The wingspan is 30–35 mm. The upperside forewings wings are ash to light brownish gray. Darkened and light forms occur. The banding is also variable. Three black crossbars are strong and usually reach the front edge. According to the variability of colour and bars several formæ have been described.
The larva is brownish, greenish, greenish-grey or violet-brown. The longitudinal lines and the incisions of the segments are usually yellowish or whitish, often with enlarged stains. The longitudinal lines are often interrupted or dissolved to elongated points.
The pupa is reddish-brown to dark reddish-brown. The cremaster is blunt-conical. The moths flies from March to July depending on the location. The caterpillars feed on birch. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Snowdonia National Park | 🇬🇧 United Kingdom | |
| 2 | Bavarian Forest National Park | 🇩🇪 Germany | |
| 3 | Wadden Sea National Park | 🇩🇪 Germany |
Rare
Under 5% of wildlife watchers report a Grey Birch Moth sighting in Helsinki on a given day, based on 9 verified sightings from GBIF citizen-science data. It is the 509th most-seen of the 838 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.
May
In that month about 10% of wildlife watchers report a Grey Birch Moth in Helsinki on a given day, against under 5% in June to April, the lowest months.
Between 10 pm and 1 am
Across all the parks we cover, that three-hour window holds the most Grey Birch Moth sightings with a recorded time, and about half of them come between 6 pm and 6 am: it is seen both by day and at night.
Yes
Of the 2 cities where we can rate Grey Birch Moth sightings, Helsinki has the highest daily chance: under 5%. Next come Moscow (Russia, under 5%).
Same family: Geometridae
The closest relatives of the Grey Birch Moth that you can see in Helsinki (family Geometridae, Geometer Moths) are Common Carpet Moth (about 10%), Mottled Umber (about 10%) and Latticed Heath (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Grey Birch Moth is recorded against all the insects logged in Helsinki (9 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.
