I'm interested in how these results may relate to maintenance of urchin barrens habitats vs. transitioning back an to M. pyrifera dominated system. You briefly touch on this (Lines 246-251), but suggest that urchins would relatively quickly consume the available Chondracanthus. What are the relative abundances of understory algal spp. in persistent barrens habitats? Zero? Also, did you notice any behavioral differences when urchins were feeding on different spp. that could affect susceptibility to predation? IE, ease of grazing on red algae v. brown, time spent grazing, etc. Thanks!