This part of DS 781 presents data for the acoustic-backscatter map of Monterey Canyon and Vicinity map area, California. Backscatter data are provided as separate grids depending on mapping system and processing method. These metadata describe acoustic-backscatter data collected by Monterey Bay Aquarium Research Institute (MBARI) and processed by the U.S. Geological Survey. The raster data files are included in "BackscatterB_EM300_MontereyCanyon.zip," which is accessible from https://doi.org/10.3133/ds781. These data accompany the pamphlet and map sheets of Dartnell, P., Maier, K.L., Erdey, M.D., Dieter, B.E., Golden, N.E., Johnson, S.Y., Hartwell, S.R., Cochrane, G.R., Ritchie, A.C., Finlayson, D.P., Kvitek, R.G., Sliter, R.W., Greene, [...]