The NMMF is collaborating with the Universitat Politècnica de Catalunya (UPC) in the Amazon to obtain a better understanding of the population structure and habitat use of the tucuxi (Sotalia fluviatilis) and the boto (Inia geoffrensis). Both of these odontocetes are threatened by human encroachment, fishing, and other activities in the Amazon. The IUCN has designated the boto as endangered, but no designation has been made for the tucuxi because it is considered data deficient, i.e. population sizes and habitat usage are largely unknown. The NMMF funded the installation of an acoustic recording node in an area believed to be frequently used by the dolphins. The data collected by the node contributes to improving our understanding of habitat use and resolving data deficiencies. The long-term goal of the effort is to establish a network of passive acoustic monitors throughout the Amazon that allow for real-time, remote monitoring for the presence of the river dolphins.