Skip to main content

Invasive Aedes Mosquitoes

Aedes aegypti mosquito

Aedes aegypti  is an invasive species of mosquitoes that is not native in California. Since this mosquito was first identified in the Central Valley and Southern California in 2013, it has been spreading northward, most recently being detected in Placer and Sacramento counties in 2019. These small black and white mosquitoes are highly adaptive and typically breed in small artificial and natural containers such as tires, bird baths, buckets, flower pots, and bromeliads. The desiccation-resistant eggs that these mosquitoes lay on the sides of containers can remain there for several months before hatching, often making it difficult to control the populations. Adults prefer to feed on humans, and can be aggressive daytime biters. Currently, Ae. aegypti are found in 16 counties in California.

Physical characteristics:

  • Small (1/8 – ¼ inch in length)
  • Black and white body
  • Black legs with white stripes
  • Lyre-shaped marking on thorax (distinctive to this species)

 

Aedes albopictus mosquito

Aedes albopictus is another invasive species of mosquito that has become established in southern California since 2011. It has spread to neighboring areas but remained in the southern portion of the state. Similar to other invasive Aedes mosquitoes, Ae. albopictus is a small black and white mosquito that lays desiccation-resistant eggs on the sides of both artificial and natural containers. It is currently found in 5 counties in California.

Physical characteristics:

  • Small (1/8 to ¼ inch in length)
  • Black and white body
  • Black legs with white stripes
  • Striking white stripe down thorax

Human health impact

Both Aedes aegypti and Aedes albopictus have the potential to transmit several human viruses, including dengue, chikungunya, Zika and yellow fever.  They are also both considered nuisance species as they are aggressive daytime biters, feeding both indoors and outdoors.

How to prevent invasive Aedes breeding sites

 

Scroll through the gallery to view invasive mosquitoes and the place they like to lay their eggs.

Remove artificial containers – Remove any unnecessary water-holding containers from your property.

Dump standing water – The eggs of invasive Aedes mosquitoes can survive for long periods of time on the side of containers, waiting for the containers to fill with water. Invasive Aedes can develop from egg to adult mosquito in 7-10 days in the right conditions, so dumping water each week will prevent the adults from emerging.

 

Contact the Marin/Sonoma Mosquito and Vector Control District (800) 231-3236 – If you are noticing mosquitoes and would like a technician to come inspect your property and look for potential sources.

 Brochures

Invasive Mosquito Species of California

 

Additional information:

 

Centers for Disease Control Travel Information- Zika virus