Rhionaeschna californica
In 3 days ~10% in a week ~20%
Rhionaeschna californica, the California darner, is a species of darner in the dragonfly family Aeshnidae. It is commonly found in Central America, along the West Coast of the United States, and in Southwestern Canada. The California darner prefers habitats like lakes, ponds, marshes and stream pools with edge vegetation including many with alkaline water conditions Larvae sustain themselves on a diet of aquatic insects, very small fish and tadpoles. The adult-stage will eat almost any soft-bodied flying insect.
The IUCN conservation status of Rhionaeschna californica is "LC", least concern, with no immediate threat to the species' survival. The population is stable. The IUCN status was reviewed in 2017. As an adult, the California darner is described as a medium-sized dragonfly, typically measuring between 5.7 and 6.4 centimetres (2+1⁄4 and 2+1⁄2 in) in length. California darners are best distinguished by their distinct bright blue diagonal spots on their abdomen.
Male California darners have a dark brown to brownish-black body with two blue or green diagonal stripes across each side of the thorax, while the top thorax is plain in color. Most females are polymorphic... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Redwood National Park | 🇺🇸 United States |
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Portland | 🇺🇸 United States | |
| 2 | Seattle | 🇺🇸 United States | |
| 3 | Vancouver | 🇨🇦 Canada | |
| 4 | San Francisco | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a California Darner sighting in San Francisco on a given day, based on 46 verified sightings from GBIF citizen-science data. It is the 240th most-seen of the 737 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.
April
In that month about 10% of wildlife watchers report a California Darner in San Francisco on a given day, against under 5% in May to March, the lowest months.
Between 1 and 4 pm
Across all the parks we cover, that three-hour window holds the most California Darner 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 cities where we can rate California Darner sightings, San Francisco ranks 4th at under 5%. The best odds are in Portland (United States, about 10%), Seattle (United States, about 10%) and Vancouver (Canada, under 5%).
GBIF citizen-science records
It is estimated from how often the California Darner is recorded against all the insects logged in San Francisco (46 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.
