Hydrometra stagnorum
In 3 days ~10% in a week ~30%
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 |
With luck
About 10% of wildlife watchers report a Common Water Measurer sighting in Paris on a given day, based on 28 verified sightings from GBIF citizen-science data. It is the 263rd most-seen of the 916 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 30%, if each day is a fresh chance.
March, May–July and September
In those months about 10% of wildlife watchers report a Common Water Measurer in Paris on a given day, against under 5% in April, August and October–February, 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.
Yes
Of the 12 cities where we can rate Common Water Measurer sightings, Paris has the highest daily chance: about 10%. Next come Porto (Portugal, under 5%) and Berlin (Germany, under 5%).
Same order: Hemiptera
The closest relatives of the Common Water Measurer that you can see in Paris (order Hemiptera, True Bugs, Hoppers, Aphids, and allies) are European Firebug (about 40%), Southern Green Stink Bug (about 30%) and Brown Marmorated Stink Bug (about 30%), 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 Paris (28 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.
