A limnological assistant with a Van Dorn sampling bottle at Lake Titicaca, Peru. Researchers at the University of California Davis, and the University of British Columbia have worked with Peru's Instituto del Mar to understand limnological characteristics of this high-altitude lake (3800 m; 12,500 ft) located in the Peruvian and Bolivian altiplano. The Van Dorn water bottle can be lowered to any depth in the lake, and then triggered to collect a 10-L water sample for chemical and biological analyses.