Kelp Forests versus Urchin Barrens: Alternate Stable States and Their Effect on Sea Otter Prey Quality in the Aleutian Islands

Figure 3

Sea urchin biomass per unit area and biomass per individual urchin from remnant kelp forest and urchin barren communities throughout the central and western Aleutian Islands. Significant differences at 𝑃≤0.05 level are indicated by (*).