Which toad is this?
(Fowler's or American)
One of the most common identification challenges for new and old herpers is “What toad is this?” Often, geography is the biggest hint (see below). In many areas of the northeast, the American Toad (Anaxyrus americanus) is the only toad, which makes identification easy. However, along the coast, the Fowler’s Toad (Anaxyrus fowleri) also occurs, and looks extremely similar to the common American Toad.
Fortunately, there are two key features that can help you differentiate the two species:
Fortunately, there are two key features that can help you differentiate the two species:
- Belly pattern (spotted or unspotted)
- Dorsal “warts” (many per spot or few per spot)
Note: Color is NEVER a good way to identify these two toads. Often fowleri are lighter then americanus, but you should never rely on this method.
The next characteristic is a bit harder, but once learned is very useful. Toads have “spots” and “warts” on their back. The warts are not actually warts, just raised bumps. I should note that you cannot catch warts from a toad, unless that toad is a person, and that toad person has HPV. So, the moral of the story is get your daughters vaccinated to prevent cervical cancer. Wait, no. The moral is that toads don’t have warts (but seriously, cervical cancer is a bitch, so get your kids vaccinated). Anyway, back to toads.
If you look at the back of a toad, the spots (usually outlined in black) have warts on them. In the American Toad, there are usually 1-2 warts per spot. In the Fowler’s Toad, there are multiple warts, usually 3-5 warts per spot. Fowler’s Toads will have spots with 1-2 warts, but if you see that the overall trend on the back of your toad is for multiple (3-5) spots, you have yourself a fowleri. I have found this to be the strongest trait to use when differentiating these species, as sometimes the belly can be inconclusive.
If you look at the back of a toad, the spots (usually outlined in black) have warts on them. In the American Toad, there are usually 1-2 warts per spot. In the Fowler’s Toad, there are multiple warts, usually 3-5 warts per spot. Fowler’s Toads will have spots with 1-2 warts, but if you see that the overall trend on the back of your toad is for multiple (3-5) spots, you have yourself a fowleri. I have found this to be the strongest trait to use when differentiating these species, as sometimes the belly can be inconclusive.
Now compare this to the image below, where I've outlined (in red) the wart clusters.
Now, there are some other morphological features that differentiate the two species. One can look at the proximity of the cranial crests to the paratoid gland, and one can look at the overall “warty-ness” of the femur (americanus has a “warty-er” femur). I usually only use these when the first two methods fail, as you will sometimes find americanus that look like fowleri and vice-versa. It also doesn’t help that the two will hybridize, but that isn’t too common.
After morphology, (including their songs, which are different), ask yourself “am I in an area with no American Toads?” It seems simple, but many people don’t realize that there are very specific range maps for most animals, and they can be easily googled if a field guide isn’t available. For example, consider the ranges of both toads in NY:
In other words, if you are out on Long Island, your toad is by default fowleri, and if you are in the Adirondacks, it’s americanus. That said, you should always check, because toads like to hop around, sometimes in flower pots spread via nurseries. Finally, it’s always a good idea to take into account the natural history of the toad in question, particularly where both species occur: are you in a sandy, xeric area with low tree cover? Then there is a good chance it is a Fowler’s. Are you in a mountainous stand of Douglas Fir? It’s probably an American.
Well, there you have it. I’d also encourage you to also learn the calls of each species, as they are a dead give-away as to which species it is:
Well, there you have it. I’d also encourage you to also learn the calls of each species, as they are a dead give-away as to which species it is:
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Happy herping!
PS: if you hold a moist Fowler’s Toad up to your nose and take a good deep sniff, most will smell like raw peanuts. Interestingly, American Toads never smell like raw peanuts. The more you know…
Quiz time! Hover over the photo for the answer. Feel free to discuss HOW I made the identification for each toad in the comments.
PS: if you hold a moist Fowler’s Toad up to your nose and take a good deep sniff, most will smell like raw peanuts. Interestingly, American Toads never smell like raw peanuts. The more you know…
Quiz time! Hover over the photo for the answer. Feel free to discuss HOW I made the identification for each toad in the comments.