Hydrometra stagnorum
In 3 days ~10% in a week ~20%
Hydrometra stagnorum, the common water-measurer, is a species of aquatic bugs in the family Hydrometridae, the water measurers. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Cévennes National Park | 🇫🇷 France | |
| 2 | Sierra Nevada National Park | 🇪🇸 Spain | |
| 3 | Pyrénées National Park | 🇫🇷 France | |
| 4 | Wadden Sea National Park | 🇩🇪 Germany |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Paris | 🇫🇷 France | |
| 2 | Porto | 🇵🇹 Portugal | |
| 3 | Berlin | 🇩🇪 Germany | |
| 4 | Hamburg | 🇩🇪 Germany | |
| 5 | Munich | 🇩🇪 Germany | |
| 6 | London | 🇬🇧 United Kingdom | |
| 7 | Essen | 🇩🇪 Germany | |
| 8 | Birmingham | 🇬🇧 United Kingdom | |
| 9 | Warsaw | 🇵🇱 Poland | |
| 10 | Copenhagen | 🇩🇰 Denmark |
Rare
Under 5% of wildlife watchers report a Common Water Measurer sighting in Wadden Sea National Park on a given day, based on 8 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 536th most-seen of the 818 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.
February to April
In those months about 10% of wildlife watchers report a Common Water Measurer in Wadden Sea National Park on a given day, against under 5% in May to January, the lowest months.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Common Water Measurer sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
4th of 4
Of the 4 parks where we can rate Common Water Measurer sightings, Wadden Sea National Park ranks 4th at under 5%. The best odds are in Cévennes National Park (France, about 10%), Sierra Nevada National Park (Spain, about 10%) and Pyrénées National Park (France, under 5%).
Same order: Hemiptera
The closest relatives of the Common Water Measurer that you can see in Wadden Sea National Park (order Hemiptera, True Bugs, Hoppers, Aphids, and allies) are Western Conifer Seed Bug (about 10%), Green Shield Bug (about 10%) and Forest Bug (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Common Water Measurer is recorded against all the insects logged in Wadden Sea National Park (8 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.
