Crayfish serve important roles in aquatic ecosystems through their ability to change macrophyte biomass, manipulate substrate, break down detritus, and serve as prey for numerous fish species. Despite their importance, life history studies have only been published for twelve percent of native U.S. crayfishes. In this study, we characterize the life history of the vernal crayfish, the most dominant and possibly taxonomically distinct crayfish species in vernal pool habitats in the Dahomey National Wildlife Refuge in the Lower Mississippi Alluvial Valley. The vernal crayfish had a two to three year lifespan, maturing at the end of the first or the beginning of the second year. Form 1 males were collected throughout the study. Abundance patterns of Form 1 males and females suggested that breeding peaked in May, with small juveniles becoming abundant in January and February. We estimated that 41 to 55 stage 3 young were produced by females in this population. The best habitats for collecting the vernal crayfish were in seasonal wetlands, with pools present for three or more months. Conditions were most favorable in these wetlands as pool water level declined and three-day average water temperatures rose above ten degrees Celsius.