Anaxyrus woodhousii
Silhouette: Michael Scroggie, from original photograph by Gary M. Stolz, USFWS (original photograph in public domain). · PhyloPic
In 3 days ~50% in a week ~80%
Woodhouse's toad (Anaxyrus woodhousii) is a medium-sized (4 inches or 10 centimetres) true toad native to the United States and Mexico. There are three recognized subspecies. A. woodhousii tends to hybridize with Anaxyrus americanus where their ranges overlap.
Woodhouse's toad was first described in 1854 by the French herpetologist Charles Frédéric Girard. He gave it the name Bufo woodhousii in honor of the American physician and naturalist Samuel Washington Woodhouse. The large genus Bufo was split by Frost et al. in 2006, with the North American species being included in the genus Anaxyrus and this toad becoming A. woodhousii. There are three recognised subspecies:
Rocky Mountain toad – Anaxyrus woodhousii woodhousii (Girard, 1854) East Texas toad – Anaxyrus woodhousii velatus (Bragg and Sanders, 1951) Southwestern Woodhouse's toad – Anaxyrus woodhousii australis (Shannon & Lowe, 1955)
At one time, Fowler's toad (Anaxyrus fowleri) was considered to be a subspecies. Woodhouse's toad is a robust amphibian and can grow to a maximum snout-vent length of 127 mm (5 in). The head has prominent cranial crests in front of and in between the eyes. The parotoid... Wikipedia →
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| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Badlands National Park | 🇺🇸 United States | |
| 2 | Grand Canyon National Park | 🇺🇸 United States | |
| 3 | Death Valley National Park | 🇺🇸 United States | |
| 4 | Padre Island National Seashore | 🇺🇸 United States | |
| 5 | Zion National Park | 🇺🇸 United States |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Phoenix Zoo | 🇺🇸 United States | |
| 2 | Arizona-Sonora Desert Museum | 🇺🇸 United States | |
| 3 | Oklahoma Aquarium | 🇺🇸 United States | |
| 4 | Schramm Education Center | 🇺🇸 United States | |
| 5 | Medicine Park Aquarium & Natural Sciences Center | 🇺🇸 United States |
Possible
About 20% of wildlife watchers report a Woodhouse's Toad sighting in Denver on a given day, based on 272 verified sightings from GBIF citizen-science data. Over three days the chance rises to about 50%, and over a week to about 80%, if each day is a fresh chance.
July and August
In those months about 40% of wildlife watchers report a Woodhouse's Toad in Denver on a given day, against under 5% in November to April, the lowest months. Those are among Denver's wettest months, with about 55 mm of rain a month against 15 mm in January.
Between 8 and 11 pm
Across all the parks we cover, that three-hour window holds the most Woodhouse's Toad sightings with a recorded time, and about 6 in 10 of them come between 6 pm and 6 am: it is seen both by day and at night.
Yes
Of the 5 cities where we can rate Woodhouse's Toad sightings, Denver has the highest daily chance: about 20%. Next come Mesa (United States, about 20%) and Phoenix (United States, about 10%).
Same order: Anura
The closest relatives of the Woodhouse's Toad that you can see in Denver (order Anura, Frogs and Toads) are American Bullfrog (about 20%) and Boreal Chorus Frog (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Woodhouse's Toad is recorded against all the amphibians logged in Denver (272 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.
