Anaxyrus americanus
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%
The American toad (Anaxyrus americanus) is a common species of toad found throughout the eastern half of Canada and the United States. Taxonomic treatments in 2006 placed this species in the genus Anaxyrus instead of Bufo.
A. americanus lays eggs in two long ropes of 2,000-20,000 small black eggs (1-2mm in diameter) surrounded by jelly. Egg strings are in shallow water, typically entwined around vegetation or laying on the bottom of the pond.
American Toad eggs hatch into tadpoles in 3-12 days. The hatched tadpoles, while very small, are recognizable by their skinny tails in relation to the size of their round black bodies. They reach adulthood in 50–65 days. When metamorphosis is complete, the "toadlets" may stay in the water for a short period of time before transitioning to be mostly land based. Often times, groups of tadpoles reach the toadlet stage at once and a begin a mass migration to higher ground. Typically, toadlets migrate to shaded areas in the mid-range and upland forests... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Gros Morne National Park | 🇨🇦 Canada | |
| 2 | Isle Royale National Park | 🇺🇸 United States | |
| 3 | Cape Breton Highlands National Park | 🇨🇦 Canada | |
| 4 | Voyageurs National Park | 🇺🇸 United States | |
| 5 | Shenandoah National Park | 🇺🇸 United States | |
| 6 | Point Pelee National Park | 🇨🇦 Canada | |
| 7 | Great Smoky Mountains National Park | 🇺🇸 United States | |
| 8 | Acadia National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 2 | Detroit | 🇺🇸 United States | |
| 3 | Toronto | 🇨🇦 Canada | |
| 4 | Philadelphia | 🇺🇸 United States | |
| 5 | Montreal | 🇨🇦 Canada | |
| 6 | Washington | 🇺🇸 United States | |
| 7 | Baltimore | 🇺🇸 United States | |
| 8 | Boston | 🇺🇸 United States | |
| 9 | Chicago | 🇺🇸 United States | |
| 10 | New York City | 🇺🇸 United States |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | National Zoological Park | 🇺🇸 United States | |
| 2 | Ecomuseum Zoo | 🇨🇦 Canada | |
| 3 | Minnesota Zoo | 🇺🇸 United States | |
| 4 | Squam Lakes Natural Science Center | 🇺🇸 United States | |
| 5 | Toledo Zoo | 🇺🇸 United States | |
| 6 | Philadelphia Zoo | 🇺🇸 United States | |
| 7 | Bayou Safari Wildlife Park | 🇺🇸 United States | |
| 8 | Western North Carolina Nature Center | 🇺🇸 United States | |
| 9 | Como Park Zoo and Conservatory | 🇺🇸 United States | |
| 10 | Como Zoo | 🇺🇸 United States | |
| 11 | Trailside Museum & Zoo | 🇺🇸 United States | |
| 12 | Blue Hills Trailside Museum Habitats | 🇺🇸 United States | |
| 13 | National Aquarium | 🇺🇸 United States | |
| 14 | Critchlow Alligator Sanctuary | 🇺🇸 United States | |
| 15 | Snake Discovery: A Reptile Experience | 🇺🇸 United States |
Possible
About 20% of wildlife watchers report an American Toad sighting in Boston on a given day, based on 512 verified sightings from GBIF citizen-science data. It is the most-seen of the 11 amphibians we can rate there. Over three days the chance rises to about 50%, and over a week to about 80%, if each day is a fresh chance.
April to August
In those months about 30% of wildlife watchers report an American Toad in Boston on a given day, against under 5% in November to March, the lowest months.
Between 7 and 10 pm
Across all the parks we cover, that three-hour window holds the most American Toad sightings with a recorded time, and about 6 in 10 of them come between 6 am and 6 pm: it is seen both by day and at night.
8th of 10
Of the 10 cities where we can rate American Toad sightings, Boston ranks 8th at about 20%. The best odds are in Minneapolis [Saint Paul] (United States, about 40%), Detroit (United States, about 40%) and Toronto (Canada, about 30%).
Same order: Anura
The closest relatives of the American Toad that you can see in Boston (order Anura, Frogs and Toads) are American Bullfrog (about 20%), Green Frog (about 10%) and Wood Frog (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the American Toad is recorded against all the amphibians logged in Boston (512 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.
