The mainland SBC kelp forest canopies showed high amounts of spatial variability in Chl:C of the surface canopy in April 2013 (Fig. 6a). Chl:C estimated from the AVIRIS imagery ranged from 0.005 to 0.025 mg mg− 1, with a mean Chl:C of 0.012 (0.003 s.d.) mg mg− 1. This is similar to the observed Chl:C mean and range of sampled mature, healthy canopy blades across all sample dates, which were 0.012 and 0.005–0.030 mg mg− 1, respectively. Chl:C was only estimated for pixels with a high proportion of emergent kelp canopy (canopy fractional cover of 0.4 as estimated by MESMA).