RT Journal Article
SR Electronic
T1 Grazer behavior can regulate large-scale patterns of community states
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 722215
DO 10.1101/722215
A1 Vadim A. Karatayev
A1 Marissa L. Baskett
A1 David J. Kushner
A1 Nicholas T. Shears
A1 Jennifer E. Caselle
A1 Carl Boettiger
YR 2019
UL http://biorxiv.org/content/early/2019/08/30/722215.abstract
AB Ecosystem patterning can frequently arise from either environmental heterogeneity or biological feedbacks that produce multiple persistent ecological states. One such possible feedback is density dependent changes in behavior that regulates species interactions, which raises the question of whether behavior can also affect large-scale community patterns. On temperate rocky reefs, kelp and urchin barrens can form mosaics if urchins locally avoid predators and physical abrasion in kelp stands or large-scale patches when starvation intensifies grazing across entire reefs at low kelp density. By fitting dynamical models to large-scale surveys, we find that these behavioral feedbacks best explain observed spatial patterning. In our best-supported models reef-scale feedbacks create reef-scale, alternatively stable kelp- and urchin-dominated states at 37% of reefs in California. In New Zealand, local feedbacks limit this phenomenon to 3-8m depths with moderate wave stress on kelp, with distinct single stable states in exposed shallows and sheltered, deeper areas. Our results highlight that differences in grazer behavior can explain ecosystem patterning.