A total of 95 cane toads approached the feeding stations within a two-hour period, with an almost even mix between those happy to eat on their own and those that preferred another toad to be present.
Shine says the presence of another toad in the area provided some of the toads with valuable social cues about the suitability of the area for foraging. But for those toads that fed alone, the social cues weren't needed.
To further test their personalities, the researchers placed each toad into a makeshift shelter in the laboratory and timed how long it took for the toad to leave the shelter and begin exploring its new environment.
They found the cane toads that happily ate on their own left their shelters much quicker than the more social cane toads, which tended to be more timid.
Bold v timid toads
"The bolder toads were happy to waltz out and walk around and the other guys stayed hiding," says Shine.
"It shows that some toads are prepared to leap out there into the unknown while some are scaredy-cats."
Shine believes it is the bold cane toads that venture forth and invade new areas. The shy toads follow on later, using social cues from the bolder toads to guide them. The result is a rapid swell in cane toad numbers in the first few years following the invasion into a new area.
"To boldly go where no toad has gone before is probably the sort of thing that a bolder individual is going to do better than a shy individual."
While there are advantages to being a bold toad, such as less competition for food, Shine says there is also the added risk of greater predation.
"Being the bold toad may well pay off or it may end up with you being dinner for the local rats," he says.
"So a population with a mix of personalities is probably going to do better than either one alone. You need a few extroverts as well as a few introverts."
Article originally appeared on ABC Science.