Effects of nutritional factors and soil addition on growth, longevity and fecundity of the tadpole shrimp Triops newberryi (Notostraca: Triopsidae), a potential biological control agent of immature mosquitoes.

The notostracan tadpole shrimp (TPS) Triops newberryi Packard has potential to be used as a biocontrol agent of immature mosquitoes. Eggs, nymphal or adult shrimps are considered to be the stages for field introduction. To yield good growth of the shrimp and high production of shrimp eggs under artificial conditions, nutritional requirements of TPS for growth, survival and fecundity need to be elucidated. In the laboratory, we evaluated various nutritional and edaphic regimens, such as soil alone, mosquito larvae or rabbit pellets alone and various combinations of these three components for culturing. These factors influenced the growth, longevity and egg production profoundly. It was shown that the simulated natural conditions, i.e. full combination of all three factors, yielded the largest TPS with longest survival and highest egg production, followed by the combinations of any two components. Any single component, soil, mosquito larvae, or rabbit pellets, did not result in good growth, survival and egg production. By formulating optimal rearing substrates, this species of TPS will yield large numbers of all stages for experimentation and field introductions. Under optimal conditions, they mature in 7-8 days and survive for about one month. Each TPS is capable of producing up to 1,000 eggs during its lifetime. These studies developed nutritional regimens for TPS mass culturing procedures, where the eggs, nymphal and adult TPS can be mass cultured for field introduction and stocking in mosquito developmental sites.