Five-minute grid of total marine bird biomass densities surveyed off central California - selected warm water periods, 1980-2001 (CDAS data set AL1_MASS.shp)

AL0_MASS is a polygon shapefile representing 5 minute x 5 minute latitude x longitude cells that house the overall total biomass densities (kg/sq.km.) of 76 species of marine birds regardless of season and/or oceanic conditions. Density for each of 76 marine bird species was multiplied by average body mass for that species, and these products summed for all species in a cell, to obtain total biomass density. Cells that were surveyed but in which no birds were observed have total biomass densities of zero.