The green toad can tolerate extreme environmental conditions, such as temperatures of 40 degrees Celsius (2) and high degrees of salinity, and it can remain buried for several months at a time in dry soils (7). It is quite tolerant of drying out, regularly visiting water sources at night to rehydrate in dry regions (2).
This species hibernates in many areas, mostly on land but occasionally in water sources such as streams, ditches or wells, either alone or as part of a group. However, in the southernmost parts of its distribution hibernation may not occur, and in some areas aestivation may happen instead. The exact timing of hibernation varies significantly throughout the green toad’s range (2).
The reproductive period of the green toad varies from February to July, depending on the location (2). It is generally longest in the south (2) and can be affected by rainfall (4). The male green toad clasps the female under the front legs during mating, and may hold this position for a few days until the female lays her eggs (3). Spawning usually takes place in water bodies no deeper than 50 centimetres (2). Each female green toad may lay between 5,000 and 13,000 eggs (3), with the eggs being deposited in 2 strings of about 2 to 7 metres in length (2).
The tadpoles of the green toad undergo metamorphosis in spring and summer. The newly metamorphosed juveniles often emerge in large numbers, covering pond shores with thousands of small toadlets. The maximum lifespan of the green toad has been estimated at around seven to ten years (2).
The adult green toad is mainly nocturnal, emerging at dusk to find insects to consume. However, it may also be active in the daytime during the breeding season (2) (3). The adult green toad is mainly terrestrial (7). Green toad tadpoles feed on detritus and algae (2).
If threatened, the green toad may secrete a noxious fluid that has been known to cause discomfort and even convulsions in animals that come into contact with it (3). Despite this, the green toad is included in the diets of many predatory animals, such as snakes (2).