Invertebrate communities in vegetated playa wetlands

Playa wetland invertebrates are important to the biodiversity in the Southern High Plains (SHP) and as food sources for waterfowl and other wildlife. Annual production of foods for wildlife in playas are about 24.3 million kg of seed and invertebrate food, 9.2 million kg of protein, and 108.6 billion kcal of energy. Total protein produced from invertebrates was greater than protein produced from seeds. In average years, playa wetlands can provide enough seeds and invertebrates for 3 million ducks for 3 months.; Eighty-seven macroinvertebrate taxa (families) were collected during the study; 85 during fall and 70 during winter. Moist-soil managed playas, when averaged across flooding date, had greater than 3 times more invertebrates based on density and biomass. Invertebrate familial richness and diversity was greater in moist-soil managed than in unmanaged playas. Moist-soil management and flooding date both influenced invertebrate abundance in managed playas, however, moist-soil management appeared more important.; At least 26 invertebrate taxa survive seasonal drying of playas through diapause in soil. More invertebrate taxa colonize flooded playas (70.1%) rather than persist in dry soil (29.9%). Of the invertebrate taxa that persist in dry soil, more of these were also active colonists or relied strictly on diapause rather than a combination of diapause and passive colonization. Many taxa practice multiple mechanisms of surviving dry periods in playas to increase chances of long-term survival.; Invertebrate abundance generally increased as water depth, dissolved oxygen, and temperature increased, and as electrical conductivity and pH decreased. Planorbidae was the only taxa to increase in abundance as temperature decreased, and may explain why it was the most numerous of the invertebrate taxa. Differences in vegetation were responsible for the largest differences among snail niches. Competition among snails in playas is limited due to abundant resources and preferences for particular combinations of resources.; Playas are essential for conserving invertebrate biodiversity on the SHP. Moist-soil management and September flooding can increase invertebrate production and diversity and produce abundant invertebrates during winter for nonbreeding waterfowl. Moist-soil regimes that favor pink smartweed (Persicaria pensylvanicum) and barnyard grass (Echinochloa crusgalli) growth should be encouraged to increase invertebrate abundance.