Mosquito Swarm Bites Californians as Temperatures Rise

As of November 11th, 2025, residents in the Sacramento area have been dealing with a significant increase in mosquito activity, with many reporting being "eaten alive" by the biting insects. According to Jake Hartle, the deputy general manager of the Placer County Vector Control District, the recent weather conditions have created the perfect storm for a mosquito population boom.

The heavy rainfall in October, followed by warmer temperatures, has led to the formation of standing water, which serves as a breeding ground for mosquitoes. Additionally, the rain has caused an influx of invasive mosquito species to develop in people's backyards, thriving in even small amounts of water, such as a bottle cap.

Furthermore, agricultural mosquitoes have moved into urban areas to seek shelter for the winter while crops are being harvested. Hartle explains that these factors have resulted in "all kinds of conditions right now for maybe two or three different types of species to be able to provide this biting pressure."

Residents like Violet Marshall, who lives in Carmichael, and Molly Willing, who resides in Sacramento, have been particularly affected by the mosquito surge. Violet's mother has reported that her daughter, a member of the school's dance team, has been coming home from football games covered in mosquito bites. Molly has also noticed that the mosquitoes are even attracted to wet paper towels around her home.

As the temperatures continue to drop this November, Hartle expects the mosquito activity to decrease, providing relief to those who have felt like "mosquito magnets" in recent weeks.