Hypersaline lakes are noted for their simple communities which facilitate understanding ecological interactions (Williams et al. 1990; Wurtsbaugh 1992; Jellison and Melack 1988). Nevertheless, we still cannot easily predict how environmental changes will effect the population dynamics in these lakes, at least in part because even these simple ecosystems may be more complex than we .realize. Many hypersaline lakes are dominated by the brine shrimp Artemia spp. The production of brine shrimp is often very high because the terminal, saline lakes accumulate nutrients that make them rich, and because the short food chains in them (nutrients-->phytoplankton-->brine shrimp) minim ize the loss of materials and energy through trophic-transfer inefficiencies (Lindeman 1942). Brine shrimp are not, however, the end of the food chain. Waterfowl and shorebirds often depend heavily on the shrimp for food (Cooper et al. 1984; White et al. 1992). The shrimp and their cysts are also harvested commercially, primarily to support a world-wide shellfish and finfish aquaculture industry.