11. Eastern brown snake

Eastern brown snakes are endemic to eastern Australia and are responsible for more human fatalities than any other snake species in the country. Their venom is highly potent, containing powerful toxins that can cause paralysis and internal bleeding. The initial bite is often painless, according to the Australian Museum. 

"They're the only snakes in the world that regularly kill people in under 15 minutes," Bryan Fry, who studies venom at the University of Queensland, told ABC News in 2024. "Even more insidiously than that is that for the first 13 minutes, you're going to feel fine."

They generally hunt during the day and are often found in the suburbs of cities and large towns, putting them in close contact with humans. Many eastern brown snake bites are the result of people trying to kill them.