The PIs are developing a radio scanner/recorder (SRS) which will aid biologists in their field tracking of radio-tagged animals. RSR monitors radio frequencies of animals and records their presence or absence. Currently, data are retrieved from RSR by attaching a laptop computer; the PIs developing a command telemetry module (CTM) which will allow remote retrieval of data. The prototype has been tested successfully for 14 months along the Dolores River in southwestern Colorado, the site of recent reintroductions of 18 radio-tagged river otters and 20 desert bighorn sheep. Funds are requested for the development and testing of the CTM and for the development of the printed circuit board for the RSR and CTM. Funds are also requested for components and assembly of a network of instruments in order to test the system.