Vernal pool fairy shrimp. Image by Daniel Anderson and Peter J Bryant, 2010.

Vernal pool fairy shrimp

General Information: The vernal pool fairy shrimp is a small crustacean that lives in seasonal, rain-fed ponds called “vernal pools”. It has a diverse diet – indiscriminately eating particles that include bacteria and algae. It is found from southern Oregon to southern California.

CategoryFocal species
Surface Water Needs: Seasonal pools
Federal Listing Status: Endangered
State Listing Status: None

Potential Conservation Actions:  

  • Create temporary pools
  • Develop grazing plans
  • Recontour seasonal pools

Fun Fact

Vernal pool fairy shrimp swim upside down.


Vernal pool fairy shrimp relies on temporary pools of water to breed, spending most of its life in vernal pools or other temporary water found in habitats such as grasslands, oak woodlands, scrub, and chaparral in washes and floodplains. These include vernal pools, seasonal runoff, pools in creek channels or off-channel, and cattle ponds. Restoration and management of vernal pools and other temporary pools do not require imported water.

Vernal pools

Disturbance and Stressors

Habitat loss is the greatest threat to vernal pool species. Other threats include invasive species, erosion, and contamination. Cattle can help remove nonnative plants, but overgrazing can damage native plants and vernal pools.

Housing development

Solar development

Agricultural development

Oil and gas development

Vernal pool fairy shrimp. Image via US FWS.

Sources: U.S. Fish and Wildlife Services 2005, 2006, and 2007; California Department of Fish and Wildlife; Eriksen and Belk 1999
Photo credits: Daniel Anderson and Peter J. Bryant