Phoebis sennae
In 3 days ~30% in a week ~60%
Phoebis sennae, the cloudless sulphur, is a mid-sized butterfly in the family Pieridae found in the Americas. There are several similar species such as the clouded sulphur (Colias philodice), the yellow angled-sulphur (Anteos maerula), which has angled wings, the statira sulphur (Aphrissa statira), and other sulphurs, which are much smaller. The species name comes from the genus Senna to which many of the larval host plants belong.
Their range is wide, from South America to southern Canada, in particular southwestern Ontario. They are most common from Argentina to southern Texas, Georgia, and Florida, but are often visitors outside this range becoming more rare further north.
The common habitats of this butterfly are open spaces, gardens, glades, seashores, and watercourses. The adult butterfly feeds on nectar from many different flowers with long tubes including cordia, bougainvillea, cardinal flower, hibiscus, lantana, and wild morning glory. The larvae also feed on sennas and partridge peas.
Senna hebecarpa (American senna) is a larval host and nectar source for the cloudless sulphur butterfly in the Eastern United States. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Jaragua National Park | 🇩🇴 Dominican Republic | |
| 2 | Rincón de la Vieja National Park | 🇨🇷 Costa Rica | |
| 3 | Congaree National Park | 🇺🇸 United States | |
| 4 | Merritt Island National Wildlife Refuge | 🇺🇸 United States | |
| 5 | Carara National Park | 🇨🇷 Costa Rica | |
| 6 | Great Smoky Mountains National Park | 🇺🇸 United States | |
| 7 | Padre Island National Seashore | 🇺🇸 United States | |
| 8 | Galápagos Islands | 🇪🇨 Ecuador | |
| 9 | Lago de Yojoa | 🇭🇳 Honduras | |
| 10 | Big Cypress National Preserve | 🇺🇸 United States | |
| 11 | Piedras Blancas National Park | 🇨🇷 Costa Rica | |
| 12 | Bahía de Loreto National Park | 🇲🇽 Mexico | |
| 13 | Point Pelee National Park | 🇨🇦 Canada | |
| 14 | Saguaro National Park | 🇺🇸 United States | |
| 15 | Big Bend National Park | 🇺🇸 United States | |
| 16 | Joshua Tree National Park | 🇺🇸 United States | |
| 17 | Cumbres de Monterrey National Park | 🇲🇽 Mexico | |
| 18 | Everglades National Park | 🇺🇸 United States | |
| 19 | Arenal Volcano National Park | 🇨🇷 Costa Rica | |
| 20 | Shenandoah National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Toluca | 🇲🇽 México | |
| 2 | Fortaleza | 🇧🇷 Brazil | |
| 3 | San Luis Potosí | 🇲🇽 México | |
| 4 | Houston | 🇺🇸 United States | |
| 5 | Mexico City | 🇲🇽 México | |
| 6 | Puebla | 🇲🇽 México | |
| 7 | Maceió | 🇧🇷 Brazil | |
| 8 | San Diego | 🇺🇸 United States | |
| 9 | Los Angeles | 🇺🇸 United States | |
| 10 | San Antonio | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Cloudless Sulphur sighting in Great Smoky Mountains National Park on a given day, based on 90 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 74th most-seen of the 822 insects we can rate there. Over three days the chance rises to about 30%, and over a week to about 60%, if each day is a fresh chance.
October
In that month about 40% of wildlife watchers report a Cloudless Sulphur in Great Smoky Mountains National Park on a given day, against under 5% in December to June, the lowest months.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Cloudless Sulphur 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 20
Of the 20 parks where we can rate Cloudless Sulphur sightings, Great Smoky Mountains National Park ranks 6th at about 10%. The best odds are in Jaragua National Park (Dominican Republic, about 30%), Rincón de la Vieja National Park (Costa Rica, about 30%) and Congaree National Park (United States, about 20%).
Same family: Pieridae
The closest relatives of the Cloudless Sulphur that you can see in Great Smoky Mountains National Park (family Pieridae, Whites, Yellows, and Sulphurs) are West Virginia White (about 20%), Sleepy Orange (about 10%) and Orange Sulphur (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Cloudless Sulphur is recorded against all the insects logged in Great Smoky Mountains National Park (90 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.
