May 28, 2019 – The Nevada County Environmental Health Department Vector Control Program will be holding Mosquito Fish Giveaways in Grass Valley and Nevada City. All giveaways will be held from 12:00 p.m to 2:00 p.m. Both locations are drive-thru pick-ups only, please do not park and walk up to get fish.

  • May 30th: Nevada County Fairgrounds by the Gentle Giant Monument
  • June 13th: Nevada County Eric Rood Administrative Building parking lot
  • June 27th: Nevada County Fairgrounds by the Gentle Giant Monument

The mosquito fish need to be delivered to your pond within a two-hour period. The fish are not native to California and should not be placed into moving bodies of water like creeks or streams. The fish will eat mosquito larvae in ponds, watering troughs, bird baths, and unused swimming pools.

In situations where a property has temporary, seasonal ponds, drainages or ditches and they cannot be manually drained, store-bought bacterial larvacide products such as BTI can be used. Most home-use larvacide products are harmless to the environment and will not hurt people, pets, or wildlife when used properly and according to label directions. These products can often be found at various hardware, garden or pond supply stores. Also, the Nevada County Environmental Health Department provides on-site service visits for treatment requests. Call the Vector Control Program at 530-265-1500.

Nevada County Environmental Health website

Mosquito Control: Drain, Dress, Defend, Dawn and Dusk

 West Nile Virus (WNV) is a mosquito-borne disease that was originally found in Africa, and as of 1999 has moved to the United States. Approximately 80% of people do not develop any symptoms, however about 1 in 5 will get flu-like symptoms that last for a few days, with fatigue and weakness that can last for weeks or months. In a very small percentage of people, <1%, severe neurological illness, such as encephalitis or meningitis (inflammation of the brain or surrounding tissue) may occur. They may last several weeks or become permanent, however this happens in roughly 1 in every 150 people. Animals are also susceptible to WNV, including dogs and cats, but especially horses.

Remember the D’s of mosquito control: Drain, Dress, Defend, Dawn and Dusk

DRAINEmpty out anything in your yard that collects water where mosquitoes can breed.

DRESS: Your wardrobe matters if you want to fight the bite. Wear light-colored, loose-fitting clothing — preferably, long-sleeved shirts and long pants.

DEFEND: Use an EPA-approved insect repellant whenever going outdoors.

DAWN and DUSK: The World Health Organization says that the peak biting periods for mosquitoes are early in the morning and in the evening before dusk. If possible minimize time spent outdoors during these periods.

The Nevada County Environmental Health Department Vector Control Program provides information on: 1) West Nile virus and precautions people can take to minimize the risk of being bitten by mosquitoes and 2) how to eliminate mosquito-breeding areas on your property. Mosquito control information can be found at: