“A Comparison of the Community Structure of Aquatic Insects between Streams of the Tropical and Temperate Region."

This research is focused on establishing and creating a model the community structure of  benthic macroinvertebrates within streams of the Neotropical region. The current model on community structure is based off of a study done in the temperate region (e.g. River Continuum Concept). This groundbreaking research showed the distribution of the functional feeding groups (FFG) within streams of the temperate region. Further research is needed to develop a community structure model for  Neotropical streams.  Our research is done at the Las Cruces Biological station, Costa Rica. 10 sampling sites were chosen among varying 1st-3rd order streams located within the primary and secondary forests of the Las Cruces Biological Station, Costa Rica. Elevation at the grounds of the Las Cruces Biological Station are above a 1000 meters with temperatures ranging from  13-26° C at daytime. A Surber sampler was used to collect the benthic macroinvertebrates for each of the four replicates per sampling site. Identification of the macroinvertebrates are done to the lowest taxonomic level possible and then are placed into their respective functional feeding group (shredders, scrapers/grazers, collectors, and predators). The results of this fundamental research showed minimal difference in the functional groups collectors, scrapers, and predators. These groups were consistent in relative abundance throughout the specimen composition of all sites. However, the shredders showed a significant difference in percentage (Tropical-4%, Temperate-36%).  Collectors were abundant regardless of the shredder's absence. Further research could be done to explain what other organisms play the functional role for shredders within tropical streams.