Celastrina ladon
In 3 days ~20% in a week ~50%
Celastrina ladon, the spring azure or echo blue, is a butterfly of the family Lycaenidae. It is found in North America from Alaska and Canada south of the tundra, through most of the United States except the Texas coast, southern plain and peninsula Florida; south in the mountains to Colombia, also on Molokai island, Hawaii.
Since the publication of a monograph on the Lycaenopsis group of lycaenid genera in 1983 by Eliot & Kawazoe, C. ladon has been considered by some taxonomic authorities to be a subspecies of C. argiolus (Linnaeus, 1758). Other authorities still consider C. ladon and related species C. neglecta and C. serotina to be "full" species.
Its wingspan is 22–35 millimetres (0.87–1.38 in). The metallic blue wings have a black margin in females. The undersides of the wings are white with speckles. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Sequoia and Kings Canyon National Parks | 🇺🇸 United States | |
| 2 | Yosemite National Park | 🇺🇸 United States | |
| 3 | Channel Islands National Park | 🇺🇸 United States | |
| 4 | Redwood National Park | 🇺🇸 United States | |
| 5 | Guadalupe Mountains National Park | 🇺🇸 United States | |
| 6 | Los Quetzales National Park | 🇨🇷 Costa Rica | |
| 7 | Grand Canyon National Park | 🇺🇸 United States | |
| 8 | Olympic National Park | 🇺🇸 United States | |
| 9 | Saguaro National Park | 🇺🇸 United States | |
| 10 | Great Smoky Mountains National Park | 🇺🇸 United States | |
| 11 | Great Bear Rainforest | 🇨🇦 Canada | |
| 12 | Grand Teton National Park | 🇺🇸 United States | |
| 13 | Rocky Mountain National Park | 🇺🇸 United States | |
| 14 | Cumbres de Monterrey National Park | 🇲🇽 Mexico | |
| 15 | Zion National Park | 🇺🇸 United States | |
| 16 | Pacific Rim National Park Reserve | 🇨🇦 Canada | |
| 17 | Glacier National Park | 🇺🇸 United States | |
| 18 | Big Bend National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Toluca | 🇲🇽 México | |
| 2 | Seattle | 🇺🇸 United States | |
| 3 | Mexico City | 🇲🇽 México | |
| 4 | San Francisco | 🇺🇸 United States | |
| 5 | Vancouver | 🇨🇦 Canada | |
| 6 | Philadelphia | 🇺🇸 United States | |
| 7 | Portland | 🇺🇸 United States | |
| 8 | Chicago | 🇺🇸 United States | |
| 9 | Boston | 🇺🇸 United States | |
| 10 | Washington | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Spring Azure sighting in Saguaro National Park on a given day, based on 56 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 59th most-seen of the 354 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 50%, if each day is a fresh chance.
January and February
In those months about 20% of wildlife watchers report a Spring Azure in Saguaro National Park on a given day, against under 5% in July to November, the lowest months. Those are among Saguaro National Park's wettest months, with about 40 mm of rain a month against almost none in May.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Spring Azure sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
9th of 18
Of the 18 parks where we can rate Spring Azure sightings, Saguaro National Park ranks 9th at about 10%. The best odds are in Sequoia and Kings Canyon National Parks (United States, about 30%), Yosemite National Park (United States, about 20%) and Channel Islands National Park (United States, about 20%).
Same family: Lycaenidae
The closest relatives of the Spring Azure that you can see in Saguaro National Park (family Lycaenidae, Gossamer-winged Butterflies) are Marine Blue (about 20%), Ceraunus Blue (about 20%) and Reakirt's Blue (about 20%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Spring Azure is recorded against all the insects logged in Saguaro National Park (56 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.
