Left: false color image of the Herschel/SPIRE mosaic in the CFHTLS-D1 overlap region (see Sect. 2.1). The SPIRE 500 μm, 350 μm, and 250 μm images served as the RGB channels, respectively. Right: sky distribution of multiwavelength galaxies also detected with SPIRE plotted against the backdrop of a density map of the 1753 galaxies in our final SPIRE sample. The spatial density of the full SPIRE sample is a convolution of the true spatial distribution (left panel) and a number of metholodological and observational effects. Bright stars, which prevent both spectroscopy and high-quality photometric redshifts, account for the presence of most of the voids seen in the background density. This includes voids around areas of otherwise high densities of SPIRE-detected sources, such as the grouping seen in the left panel at [ α_J2000,δ_J2000 ] ~ [ 36.28, −4.76 ].