The venomous snakes are common in the state and are found across all sorts of terrain, from the desert to the coast. The snake season in California usually begins in the second half of April and the beginning of May, as the weather warms up.

However, Californians have noticed rattlesnakes emerging as early as mid-March this year, NBC News reported.

In 2021, California had one of its hottest summers on record. Snakes are more common in the warmer, summer months because they need warmth to keep their metabolism efficient in digesting food. Earlier sightings of the reptiles may be down to earlier summers in the state, due to the changing climate.

Snakes are able to adapt to a warming climate, wildlife hospital and rehabilitation manager at Walnut Creek’s Lindsay Wildlife Experience, Peter J. Flowers, told NBC News.

“This is generally true of all of the species of snake that inhabit our region,” Flowers said.

Although they are venomous, rattlesnakes rarely kill people. However, their bites can be deadly or cause severe health problems if they are not treated quickly. For example, people can die from the venom if the bite is not treated within a day or so. The snakes, however, are usually not aggressive unless they are provoked.

As the snakes begin to emerge, Flowers told NBC News that people should leave them alone if they see one. He also advises avoiding long grasses, where snakes typically lurk unseen.

Regular hikers of the Mount Diablo area, Janet Keane and husband Michael, spotted a rattlesnake as early as March 19, NBC reported.

The pair spotted a hatchling on a wilderness trail and “high tailed out of there,” they told the news outlet.

“We’ve seen them before but never this early,” Janet Keane told NBC.

Rattlesnakes usually hatch in July or August. Associate pastor at the Moraga Valley Presbyterian Church and self-taught snake wrangler, Dave Ricketts, told NBC that the warm weather will cause the snakes’ eggs to hatch earlier, meaning hatchlings will be more abundant earlier in the summer.

Ricketts said the church helps prevent human—snake conflicts the area, and will continue to do so as they inevitably become more common.

NBC reported that Californians have not only seen the snakes slithering around wilderness areas, but they have also been spotted in suburban areas far earlier than usual.

Nearly the entire state of California is experiencing a drought and in 2021 The Guardian reported that this may also have something to do with an increased number of rattlesnakes lurking in and around people’s homes.

Owner of Ramirez Rattlesnake Removal company, Len Ramirez, told the newspaper that he does not believe the rattlesnake population is increasing. Rather, he thinks the increased sightings are due to the ongoing drought, and intensely dry conditions, which are driving more of the snakes into people’s homes for shelter. While snakes like warmth, they often have to find shelter if the heat becomes too intense.