Does Circulating Water Prevent Mosquitoes in a Bird Bath?

Biology

• All mosquitoes need water to hatch their eggs, but not all species lay their eggs the same way. Some, like the Culex species, lay their eggs on the surface of the water. Other species, like Aedes species, lay their eggs near water. They lay their eggs above the water line or in the mud near water and wait for rain or high tide to provide the water their eggs need to hatch. These eggs can survive for years until the right conditions exist that will trigger them to hatch.

Laying Prevention

• Moving water works as a repellent for female mosquitoes and will prevent them from laying their eggs in your bird bath. Mosquitoes look for quiet, non-flowing water that makes it easy for them to lay their eggs and will help their eggs develop. But movement is not enough to keep mosquitoes away. Some will lay their eggs on slow-moving water or in areas that are protected by rocks or ornaments in the bath. Moving water won't affect mosquitoes that lay their eggs near the water from laying eggs along the side of your bird bath.

Hatching Prevention

• According to University of Nebraska entomologists David Keith and Wayne Kramer, mosquito eggs won't hatch until the conditions become perfect. They need water with depleted oxygen. Still water has less oxygen than moving water because movement adds air to the water. So even if mosquitoes manage to lay their eggs in the water, the movement will prevent the eggs from hatching.

Survival Prevention

• Should mosquitoes manage to lay eggs that hatch, the circulating water keeps the larvae from becoming adults. Mosquito larvae breathe air through a tube or hole in their abdomen. Moving water makes it difficult for larvae to breathe and develop normally. About seven to 10 days after the eggs hatch, the larvae change into pupa. Once they emerge as adults, they need to stand on the surface of the water and dry of their wings. If they water is moving, they won't be able to do this.