Silvius gigantulus
In 3 days ~10% in a week ~20%
Silvius gigantulus is a species of horse fly in the family Tabanidae. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Olympic National Park | 🇺🇸 United States |
More parks will be added in future updates.
Rare
Under 5% of wildlife watchers report a Golden Deer Fly sighting in Olympic National Park on a given day, based on 6 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 162nd most-seen of the 207 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.
July
In that month about 10% of wildlife watchers report a Golden Deer Fly in Olympic National Park on a given day, against under 5% in August to June, the lowest months. That is one of Olympic National Park's driest months, with about 35 mm of rain against 370 mm in November.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Golden Deer Fly sightings with a recorded time, and nearly all of them come between 6 am and 6 pm: it is a daytime animal.
Only Olympic National Park, in our data
Olympic National Park is the only park on Wallace's Line with enough records to rate Golden Deer Fly sightings: under 5% of wildlife watchers there report one on a given day.
Same order: Diptera
The closest relatives of the Golden Deer Fly that you can see in Olympic National Park (order Diptera, Flies) are Common Drone Fly (about 10%), Western Pond Fly (about 10%) and Black-Margined Flower Fly (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Golden Deer Fly is recorded against all the insects logged in Olympic National Park (6 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.
