|Title||Do omnivorous shrimp influence mayfly nymph life history traits in a tropical island stream?|
|Publication Type||Journal Article|
|Year of Publication||2014|
|Authors||Macias, NA, Colon-Gaud, C, Duggins, JW, Ramírez, A|
|Journal||Revista de Biología Tropical|
|Keywords||interspecific interactions, mayflies, predator-prey, shrimp, tropical streams.|
Interspecific interactions can play an important role in determining habitat selection and resource usebetween competing species. We examined interactions between an omnivorous shrimp and a grazing mayfly,two co-dominant taxa found in Puerto Rican headwater streams, to assess how predator presence may influ-ence mayfly resource use and instantaneous growth in a tropical rainforest ecosystem. We conducted a seriesof behavioral and growth experiments to determine the effects of the freshwater shrimp,Xiphocaris elongata,on the growth rate and resource selection of mayfly nymphs in the family Leptophlebiidae. For resource choiceassessments, we conducted a series of five day laboratory experiments where mayflies were given access to tworesource substrate choices (cobble vs. leaves) in the presence or absence of shrimp. To assess for the effects ofshrimp on mayfly fitness, we measured mayfly growth in laboratory aquaria after five days using four treatments(cobble, leaves, cobble + leaves, no resource) in the presence or absence of shrimp. In resource choice experi-ments, mayflies showed preference for cobble over leaf substrata (p<0.05) regardless of the presence of shrimps,however, the preference for cobble was significantly greater when shrimp were present in the leaf habitat. Ingrowth experiments, there were no statistical differences in mayfly growth in the presence or absence of shrimp(p=0.07). However, we measured increased mayfly nymph growth in the absence of predators and when bothcobble and leaves were available. Our results suggest that interspecific interactions between these taxa couldpotentially influence organic matter resource dynamics (e.g., leaf litter processing and export) in Puerto Ricanstreams. Rev. Biol. Trop. 62 (Suppl. 2): 41-51. Epub 2014 April 01.
|Short Title||Do omnivorous shrimp influence mayfly nymph life history traits in a tropical island stream?|