Megasyrphus laxus
In 3 days ~10% in a week ~30%
Megasyrphus laxus (Osten Sacken 1875), the black-legged gossamer fly, is an uncommon species of syrphid fly observed throughout North America. Hoverflies can remain nearly motionless in flight. The adults are also known as flower flies for they are commonly found on flowers, from which they get both energy-giving nectar and protein-rich pollen. Larvae are unknown. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Acadia National Park | 🇺🇸 United States | |
| 2 | Great Bear Rainforest | 🇨🇦 Canada | |
| 3 | Great Smoky Mountains National Park | 🇺🇸 United States | |
| 4 | Olympic National Park | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Black-Legged Gossamer sighting in Olympic National Park on a given day, based on 12 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 105th 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 30%, if each day is a fresh chance.
June to August
In those months about 10% of wildlife watchers report a Black-Legged Gossamer in Olympic National Park on a given day, against under 5% in September to May, the lowest months. Those are among Olympic National Park's driest months, with about 55 mm of rain a month against 370 mm in November.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Black-Legged Gossamer sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 4 parks where we can rate Black-Legged Gossamer sightings, Olympic National Park ranks 4th at about 10%, level with the leaders once rounded. The best odds are in Acadia National Park (United States, about 10%), Great Bear Rainforest (Canada, about 10%) and Great Smoky Mountains National Park (United States, about 10%).
Same family: Syrphidae
The closest relatives of the Black-Legged Gossamer that you can see in Olympic National Park (family Syrphidae, Hover 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 Black-Legged Gossamer is recorded against all the insects logged in Olympic National Park (12 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.
