Lidar as a tool for fisheries management

摘要

This paper describes the results of a series of airborne observations of sardine schools off the coast of California in the fall of 2010. The lidar system used a linearly-polarized transmitter and a single receiver that was sensitive to the backscattered light in the orthogonal polarization. The aircraft was also equipped with a camera to photograph schools. The camera had a broader swath than the lidar, so was able to see more of the schools at the surface. However, the lidar detected schools much deeper in the water, was not hampered by waves and sun glare, and could survey at night. The combination of lidar and photographs proved to be a very powerful survey tool for sardines, since the latter was able to identify surface targets that appear very similar to fish schools in the lidar return. Examples of these include floating mats of kelp and ship wakes.