Halyomorpha halys
In 3 days ~30% in a week ~50%
The brown marmorated stink bug (Halyomorpha halys) is an insect in the family Pentatomidae, native to China, Japan, Korea, and other Asian regions. In September 1998, it was collected in Allentown, Pennsylvania, where it is believed to have been accidentally introduced. The nymphs and adults of the brown marmorated stink bug feed on over 100 species of plants, including many agricultural crops, and by 2010–11 had become a season-long pest in orchards in the Eastern United States. In 2010, in the Mid-Atlantic United States, $37 million in apple crops were lost, and some stone fruit growers lost more than 90% of their crops. Since the 2010s, the bug has spread to countries such as Georgia and Turkey and caused extensive damage to hazelnut production. It is now established in many parts of North America and has recently become established in Europe and South America.
Adult brown marmorated stink bugs are approximately 1.7 cm (0.67 in) long and about as wide, forming the shield shape characteristic of bugs in the superfamily Pentatomoidea. They are generally dark brown when viewed from above, with a creamy white-brown underside. Individual coloration may vary, with some... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Taroko National Park | 🇹🇼 Taiwan | |
| 2 | Nikko National Park | 🇯🇵 Japan | |
| 3 | Cévennes National Park | 🇫🇷 France | |
| 4 | Kiskunság National Park | 🇭🇺 Hungary | |
| 5 | Triglav National Park | 🇸🇮 Slovenia | |
| 6 | Shenandoah National Park | 🇺🇸 United States | |
| 7 | Great Smoky Mountains National Park | 🇺🇸 United States | |
| 8 | Bavarian Forest National Park | 🇩🇪 Germany | |
| 9 | Pyrénées National Park | 🇫🇷 France | |
| 10 | Fertő-Hanság National Park | 🇭🇺 Hungary |
With luck
About 10% of wildlife watchers report a Brown Marmorated Stink Bug sighting in Fertő-Hanság National Park on a given day, based on 13 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 73rd most-seen of the 243 insects we can rate there. Over three days the chance rises to about 30%, and over a week to about 50%, if each day is a fresh chance.
October
In that month about 30% of wildlife watchers report a Brown Marmorated Stink Bug in Fertő-Hanság National Park on a given day, against under 5% in March, August and November–January, the lowest months.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Brown Marmorated Stink Bug sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
10th of 10
Of the 10 parks where we can rate Brown Marmorated Stink Bug sightings, Fertő-Hanság National Park ranks 10th at about 10%. The best odds are in Taroko National Park (Taiwan, about 40%), Nikko National Park (Japan, about 30%) and Cévennes National Park (France, about 20%). All parks ranked.
Same family: Pentatomidae
The closest relatives of the Brown Marmorated Stink Bug that you can see in Fertő-Hanság National Park (family Pentatomidae, Stink Bugs) are European Striped Shield Bug (about 20%), Sloe Bug (about 20%) and Southern Green Stink Bug (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Brown Marmorated Stink Bug is recorded against all the insects logged in Fertő-Hanság National Park (13 verified sightings from 2019 to 2026), 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.
