Which statement about Culex pipiens is true?

• A. Eggs laid in rafts on water surface
• B. Overwinters as inseminated female in basements, culverts
• C. Larvae prefer clean, clear water
• D. Bites primarily humans and rarely birds

Answer: (B)

The main concept is how Culex pipiens overwinters and how that affects control strategies. In temperate areas, this species survives the winter as fertilized females that seek shelter in protected places such as basements, culverts, and other dark, damp sites. Come warmer days, these inseminated females become active again, seek blood meals, and then lay eggs to repopulate after winter. This overwintering behavior is a defining trait that directly informs when and where to target control efforts—focusing on those hidden winter refuges can reduce early-season mosquito activity.

While eggs laid in rafts on the water surface is a trait seen in Culex, it doesn’t capture the seasonal survival pattern that drives early-season emergence. The statement about larvae favoring clean, clear water isn’t correct for Culex pipiens, which often develops in standing, stagnant, and sometimes polluted water with organic material. And the idea that they bite primarily humans and rarely birds is inaccurate because Culex pipiens typically feeds more on birds, with humans as incidental hosts.