Point-source violations: split-beam tracking of fish at close range James J. Dawson, Daniel Wiggins, Donald Degan, Harold Geiger, Deborah Hart and Barbara Adams Aquat. Living Resour., 13 5 (2000) 291-295 Published online: 15 September 2000 DOI: 10.1016/S0990-7440(00)01077-9