Comparing invertebrate and seaweed diversity in kelp forests and urchin barrens in Owen Bay, British Columbia, using Autonomous Reef Monitoring Structures (ARMS)

ARMS accumulated species rapidly and did not reach an asymptote, suggesting that more than 10 replicates may be required to capture the full diversity able to settle on the ARMS. ARMS in the kelp and barren habitats were distinct, indicating a high potential for habitat resolution. We observed a very low degree of similarity between the ARMS and all other datasets included in this investigation – similarity was below 40% regardless of comparison (ARMS vs plates, ARMS vs eDNA).

We observed a trend of decreasing similarity between the ARMS and the plates from April to January, indicating some influence of priority effects on structuring ARMS communities. However, the ARMS did support an additional richness component that is likely the result of successional processes, including facilitation.