Endangered

(fws.gov)

U.S. Endangered Species Act

(fws.gov)

Their threats include habitat loss and degradation from agriculture and development, pesticides, predation from non-native bullfrogs and pressure from non-native plants, and disturbance from climate change and drought (fws.gov).

Their locations include the Central Valley, Delta and eastern San Francisco Bay. Vernal pool tadpole shrimp have variegated distribution through the Central Valley in California, ranging from Shasta County down to northwestern Tulare County, with isolated patches in Alameda and Contra Costa counties (fws.gov).

Survey Guidelines for Listed Large Branchiopods (fws.gov)

Minimum Qualifications for Recovery Permit for the Listed Large Branchiopod Species (fws.gov)

Vernal pool tadpole shrimp are only found in ephemeral freshwaters such as vernal lake and pools, alkaline pools, clay flats, and other seasonal wetlands. They are opportunistic filter feeders, eating waste from other vernal pool species and small plant matter. Females can produce up to 6 clutches of eggs, with each one containing 32-61 eggs. These eggs are carried on the female’s underside and are dropped to the bottom of the pool or sink following the female’s death. They have a life span of about 144 days and live from November and complete their life cycle in early May. They reach maturity at day 38 and reproduce by day 51 (fws.gov).

There is a general lack of studies for this species. Research topics on how vernal pool tadpole shrimp’s mating systems relate to their overall success seems generally unstudied and may be useful for determining effective strategies of how to recover their numbers.

Conservation Efforts for Vernal Pool Tadpole Shrimp (fws.gov)

These shrimp are small-bodied but have a large, flat, hardened shell that is arched over their back like a shield. They have 30-35 pairs of swimming legs that function as gills. Their eyes are fused, abdomen is segmented, and they have 2 tail-like appendages at the hind end of their bodies. Vernal pool tadpole shrimp are often compared to other vernal pool shrimp species such as fairy shrimp, although they differ mainly by the tadpole-like appearance due to the shield structure on their back (fws.gov).

Vernal Pool Tadpole Shrimp (Lepidurus packardi) | U.S. Fish & Wildlife Service (fws.gov)