The vernal pool tadpole shrimp beats its phyllopods in a wave-like motion to propel itself through the water. As it moves over the sediment or through aquatic vegetation (4), the phyllopods collect food which is funnelled to the mouth through a groove at the base of the phyllopod (3). Adult vernal pool tadpole shrimps are omnivores, feeding on detritus, vegetation and other aquatic invertebrates (3) (4). Few predators have adapted to the ephemeral pools inhabited by this shrimp, although if a connection should occur to a permanent water body, for example by flooding, the vernal pool tadpole shrimp is readily consumed by fish, against which it has no defences (3).
The vernal pool tadpole shrimp can reach maturity in just 25 days and first reproduces after an average of 54 days (6), enabling effective use of its short-lived environment. Reproduction continues until the pool dries out (7). Details of reproduction in the vernal pool tadpole shrimp are lacking, although it is thought that the species may be hermaphroditic, that is, individuals possess both male and female sex organs (6). An individual may lay up to 6 clutches of eggs during a wet season, with clutch sizes ranging between 32 and 61 eggs (2).
The eggs, also known as cysts, are drought-resistant and can withstand the high temperatures of the Californian summers while embedded in top layers of sediment. Some cysts hatch within the same wet season, although most will only hatch after the pool dries out and refills in the next rainy season. It is possible for an egg to remain dormant and viable for up to ten years (3). Once hatched, the vernal pool tadpole shrimp continues growing throughout its life, periodically moulting its shell to allow this growth (6).