Tadpole shrimp structure macroinvertebrate communities in playa lake microcosms

Abstract

Laboratory microcosms were used to assess whether tadpole shrimp, Triops sp., affect community structure of other native macroinvertebrates in playa lakes of the Southern High Plains of Texas. Removal of tadpole shrimp shortly after hatching reduced abundances of many taxa, and decreased subsequent taxonomic richness and diversity. For many invertebrates, the presence of tadpole shrimp in low numbers had a positive effect on mean abundance. Direct effects of tadpole shrimp include the reduction of prey species abundance, which in turn may alter biotic interactions among other taxa. Indirect effects include physical modification of the environment during foraging through surface sediments. Results suggest that tadpole shrimp may be a key species controlling structure of macroinvertebrate communities in playa lakes.

Ecosystem-level effects of bioturbation by the tadpole shrimp Lepidurus packardi in temporary pond mesocosms

“…They found that the presence of tadpole shrimp caused a decrease in some macroinvertebrate taxa, which they attributed to predation by T. longicaudatus, and an increase in others, which they attributed to competitive release. Yee et al (2005) also found that macroinvertebrate taxa richness in their microcosms was higher in the presence of T. longicaudatus, which they attributed to this species' predatory and foraging activities. The results of the present study are congruent with those of Yee et al (2005), as we found that TPC richness in our TPC?…”

“…Although the differences in conductivity and dissolved oxygen between treatments were small, this does not necessarily mean that their impact was negligible. For example, the hatching of zooplankton has shown a high degree of variability in some mesocosm studies (e.g., Yee et al, 2005;Gyllström et al, 2008), despite the use of well-mixed soil exposed to identical experimental conditions. Such variability implies that subtle differences in abiotic factors such as conductivity and dissolved oxygen, which are thought to play a role in breaking cyst dormancy (Brendonck, 1996;Brendonck & De Meester, 2003), are important in determining hatching rates.…”

“…Yee et al (2005), for example, used microcosms to examine how the tadpole shrimp Triops longicaudatus LeConte 1846 structured macroinvertebrate communities of playa lakes, also temporary bodies of water. They found that the presence of tadpole shrimp caused a decrease in some macroinvertebrate taxa, which they attributed to predation by T. longicaudatus, and an increase in others, which they attributed to competitive release.…”

Effect of salinity on seasonal community patterns of Mediterranean temporary wetland crustaceans: A mesocosm study

“…The most important one probably is predation by Triops. Several studies already designated Triops as a strong predator able to control invertebrate populations (Yee et al 2005;Boix et al 2006;Waterkeyn 2009). Zooplankton could also be negatively influenced by the highly efficient filter-feeding anostracans, through competition for food or interference competition (i.e., physical harassment or even predation of juvenile zooplankton stages; Sarma and Nandini 2002;Jocqué et al 2010).…”

A “crown of thorns” is an inducible defense that protectsDaphniaagainst an ancient predator

“…D. bolivari, the form with a wide and spined lobe, is reported to occur in the typical community of temporary waters, coexisting with large phyllopod crustaceans, such as fairy shrimps (Anostraca) or tadpole shrimps (Notostraca) (3). Notostracans are particularly interesting, because these omnivores, extant with unchanged morphology for 220 million years (6), may feed on Daphnia (7) and can play a key role in structuring the temporary water macroinvertebrate communities (8).…”