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About Mosquito Fish

It is against California Department of Fish and Game regulations for private citizens to plant mosquito fish in waters of the state without a permit.

May contain: water, aquatic, animal, fish, shark, and sea life

Mosquito fish are the guard dogs with gills that protect your home from mosquitoes. To be effective in preventing mosquitoes, the use of mosquito fish should be paired with a weekly habit of removing stagnant water sources around the home.

See where else mosquitoes hide in your home

The District provides FREE mosquito fish (Gambusia affinis) to properties within the District for placement on their property only. Mosquito fish are routinely stocked by Vector Control Specialists to control mosquito populations in sources such as ponds.

Request mosquito fish by calling 626-814-9466

Mosquito fish, a topminnow from North America, were first introduced to California in 1922 for mosquito control. Today they are used around the world to control mosquito larvae. The fish are an attractive and effective alternative to using pesticide to control mosquitoes. This method is referred to as biological control and is part of the Integrated Vector Management (IVM) strategy at the District.

Advantages of Using Mosquito Fish Over Other Fish In Water Sources

May contain: fish, animal, and carp
  • Gambusia are specific to consuming mosquito larvae. This is due to their upturned mouths naturally adapted for this purpose.
  • They are small, which enables them to inhabit shallow waters and penetrate dense vegetation growth where larvae and pupae hide.
  • Mosquito fish have a broad tolerance to a wide range of environmental conditions, such as temperature changes, salinity, organic pollution, and poor food supply.
  • Relative lack of disease.
  • Easily maintained.

Compatible Organisms
Gold Fish

Non-Compatible Organisms
Perch Bluegill

Placement In Swimming Pools

In some cases, mosquito fish may be placed in non-functional, partially-filled swimming pools. After an initial assessment, a Vector Control Specialist will deliver and place the fish, free of charge. A health check will be conducted a few weeks after placement to ensure that the fish survive and are effectively controlling mosquito larvae. The District will then conduct an annual health check that will be scheduled with the resident in advance through an established method of communication.

After placement, the resident is responsible for monitoring the fish population and alerting the District if the fish die or are unsuccessful in controlling mosquito larvae.

Request Mosquito Fish

Are you interested in maintaining a mosquito fish force for your home? Call us at 626-814-9466