Radiance-reflectance measurements of the main seagrass, algal and substrate types in Moreton Bay were collected during field trips in 2000 and 2001. Ten samples of each substrata were collected randomly and placed on a black background where each sample covered a homogenous 5 cm x 5 cm area. Radiance-reflectance measurements were collected using an Analytical Spectral Devices spectrometer (ASD VNIR), which recorded in the visible to infrared (400-1050 nm) wavelengths in 1024 bands (at 2 nm intervals, with a 7 nm Full-Width-Half Maximum power resolution), using a 68 field of view. Upwelling radiance measurements (Lu) were obtained in sunlight by placing the spectrometer optics 15 cm vertically above the target. A SpectralonTM panel, approximating a 100% reflective Lambertian surface, was measured prior to each sample as a surrogate for down-welling irradiance (Ed). A radiance-reflectance signature was then calculated for each sample by dividing the target radiance by the Spectralon panel radiance (Lu/Ed). A mean spectral reflectance signature was produced by averaging 10 measurements for each target. Spectral signatures include: seagrass and algae species, sand, mud and cyanobacteria (Lyngbya majuscula).