Eristalis pertinax
In 3 days ~40% in a week ~70%
Eristalis pertinax is a hoverfly in the family Syrphidae. It was first described by Giovanni Antonio Scopoli in 1763 and is found in Asia and Europe. Like Eristalis tenax, the larvae of E. pertinax are rat-tailed maggots living in drainage ditches, pools around manure piles, sewage, and similar places containing water with high organic load and low oxygen concentration.
Wing length is 8.25–12.75 mm. Antennomere 3 brown-black. Arista plumose to tip. Tarsi 1 and 2 entirely yellow. Wing with diffusely bordered darkened median band and pterostigma four times as long as wide. Dimorphic (males with triangular abdomen, females with squarish abdomen).
The male genitalia are figured by Hippa et al. (2001). The larva is figured by Hartley (1961). Palaearctic: Fennoscandia south to Iberia and the Mediterranean basin. Ireland, east through Europe to Turkey and European Russia, east to the Urals.
The habitat is wetland, forest, alluvial forest, fen, farmland, suburban gardens and parks. The flight period is February to November. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Cairngorms National Park | 🇬🇧 United Kingdom | |
| 2 | Triglav National Park | 🇸🇮 Slovenia | |
| 3 | Snowdonia National Park | 🇬🇧 United Kingdom | |
| 4 | Aigüestortes National Park | 🇪🇸 Spain | |
| 5 | Bavarian Forest National Park | 🇩🇪 Germany | |
| 6 | Hohe Tauern National Park | 🇦🇹 Austria | |
| 7 | Pyrénées National Park | 🇫🇷 France | |
| 8 | Ordesa y Monte Perdido National Park | 🇪🇸 Spain | |
| 9 | Monfragüe National Park | 🇪🇸 Spain | |
| 10 | Tatra National Park | 🇸🇰 Slovakia | |
| 11 | Białowieża National Park | 🇵🇱 Poland | |
| 12 | Sierra Nevada National Park | 🇪🇸 Spain | |
| 13 | Mercantour National Park | 🇫🇷 France | |
| 14 | Wadden Sea National Park | 🇩🇪 Germany | |
| 15 | Cévennes National Park | 🇫🇷 France | |
| 16 | Sierra de Guadarrama National Park | 🇪🇸 Spain |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Birmingham | 🇬🇧 United Kingdom | |
| 2 | Manchester | 🇬🇧 United Kingdom | |
| 3 | Liverpool | 🇬🇧 United Kingdom | |
| 4 | London | 🇬🇧 United Kingdom | |
| 5 | Leeds | 🇬🇧 United Kingdom | |
| 6 | Brussels | 🇧🇪 Belgium | |
| 7 | Amsterdam | 🇳🇱 Netherlands | |
| 8 | Rotterdam [The Hague] | 🇳🇱 Netherlands | |
| 9 | Dublin | 🇮🇪 Ireland | |
| 10 | Izmir | 🇹🇷 Turkey |
With luck
About 10% of wildlife watchers report a Tapered Drone Fly sighting in Hohe Tauern National Park on a given day, based on 8 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 85th most-seen of the 165 insects we can rate there. Over three days the chance rises to about 40%, and over a week to about 70%, if each day is a fresh chance.
July
In that month about 30% of wildlife watchers report a Tapered Drone Fly in Hohe Tauern National Park on a given day, against under 5% in February–June and August–October, the lowest months. December has too few records to rate.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Tapered Drone Fly sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
6th of 16
Of the 16 parks where we can rate Tapered Drone Fly sightings, Hohe Tauern National Park ranks 6th at about 10%. The best odds are in Cairngorms National Park (United Kingdom, about 20%), Triglav National Park (Slovenia, about 20%) and Snowdonia National Park (United Kingdom, about 20%).
GBIF citizen-science records
It is estimated from how often the Tapered Drone Fly is recorded against all the insects logged in Hohe Tauern 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.
