Amphibians
Oak Toad
Anaxyrus quercicus · also called dwarf toad
The oak toad is the runt of the toad family in North America — a warty, striped animal you could balance on a coin. It breaks several toad conventions: it is out in the daytime, it eats almost nothing but ants, and it sounds like a baby bird.
Overview
Anaxyrus quercicus lives in the sandy pinewoods and oak scrub of the southeastern US coastal plain. Adults are just 2–3.3 cm long, grey-brown and warty with a bold pale stripe down the back. It is the smallest toad in North America.
Not your average toad
It forages by day, especially after warm summer rain, and specialises on ants and other tiny invertebrates. Its call is a shrill, rapid peeping whistle, and a breeding chorus sounds uncannily like a yard full of chicks.
Home ground
It shares the fire-maintained longleaf pine sandhills with the gopher tortoise and the gopher frog, breeding explosively in shallow temporary pools after heavy downpours.
Status
The oak toad is Least Concern but declining regionally, as the longleaf pine ecosystem shrinks and its small breeding wetlands are drained.
Oak Toad: common questions
How small is an oak toad?
Very small. A big adult oak toad is about the length of an adult thumbnail, 2 to 3.3 cm, and a freshly transformed toadlet leaving the pond is only a few millimetres long, small enough to sit on a pencil eraser. It is the smallest true toad in North America and one of the smallest anywhere. The size is matched to its diet; an animal this small can make a living on ants and mites that a larger toad would ignore, and it can hide in places a bigger toad cannot.
Why does the oak toad sound like baby birds?
Most North American toads advertise with a long, steady trill produced by rapidly pulsing air over the vocal cords. The oak toad instead gives a short, very high-pitched whistling peep, repeated quickly, and when dozens of males call together at a rain pool the effect is a shrill, chirping chorus that people regularly mistake for young chickens or a flock of small birds. The unusual call is one of the easiest ways to know oak toads are present, since the toads themselves are tiny and well camouflaged.
Is the oak toad poisonous to dogs?
It has the same basic defence as other toads, glands in the skin that secrete a bitter, mildly toxic substance, but the oak toad is so small that the total dose is low, and it is far less of a hazard than the large cane toad or Sonoran desert toad, which can seriously poison or kill a dog. A dog that mouths an oak toad will likely drool, foam, and be put off, and should be offered water and watched, but serious poisoning is unlikely. In areas where cane toads or Sonoran desert toads occur, those are the real danger, not the oak toad.
Why is the oak toad declining?
It is tied to a habitat that has mostly disappeared. The longleaf pine savanna of the southeastern coastal plain once covered a vast area and is now reduced to a small fraction of its range, cleared for timber plantations, farms, and housing, and degraded where the frequent low-intensity fires it needs have been suppressed and the understorey has grown up. The oak toad also depends on small, shallow, temporary wetlands for breeding, and these are routinely drained, filled, or deepened and stocked with fish. Where the open, fire-swept pinelands and their ephemeral pools survive, the oak toad usually does too.