Over 40 years ago, Dr. Alan Covich visited Puerto Rico while on sabbatical. This began a career-long quest by Alan to understand community structure in tropical streams. He was (and remains!) a keen observer of stream communities, and quickly recognized the dominance of decapods, especially shrimps, in structuring stream communities and sediment transport. His early work established the food web of Luquillo Mountain streams, documenting the dominant role of Xipohocaris, Atya, and Macrobrachium in processing litter inputs, particle filtration, and predation. This understanding of community dynamics led to establishment of a strong stream ecology focus in the Luquillo LTER, which links stream communities, geomorphic structure, and biogeochemistry. Originally funded in 1988 and continuing to present, the LTER has shown the impact of shrimp species on carbon and nitrogen dynamics in streams, documented the importance of waterfalls that impede fish passage in controlling community structure, and quantified the effects of droughts and hurricanes on stream ecosystems. Alan has served as an enthusiastic participant and sage mentor throughout the last 40 years. He was one of the first to recognize the value of coastal tropical streams, putting them in a global context, based on a detailed assessment of the life history strategies and community dynamics of these decapod-dominated systems.