Kelp patch size and density influence secondary productivity and diversity of epifauna

• DOI: 10.1111/oik.06585
• Publication Date: 2019-11-15T13:47:15Z
• Authors: Victor Shelamoff; Cayne Layton; Masayuki Tatsumi; Matthew J. Cameron; Graham J. Edgar; Jeffrey T. Wright; Craig R. Johnson
• Keywords: Kelp forest; Understory

Habitat‐forming ecosystem engineers are the foundation of many marine ecosystems where they support diverse and productive food‐webs. A reduction in their patch size or density may affect productivity, biodiversity stability these ecosystems. We determined effects different densities sizes Ecklonia radiata (the dominant kelp southern Australia) on secondary species richness, diversity community structure understory epifaunal invertebrates how associated environmental covariates modified by affected those patterns. assessed sub‐canopy epifauna across 28 artificial reefs with transplanted E. consisting seven (0.12–7.68 m 2 ) crossed four (0–16 −2 over two years. Epifaunal productivity both natural algal standardised rope fibre habitats decreased was elevated when absent, however, it also high habitat there a kelp. positively light water flow but negatively biomass alga, Ulva sp. declined reef as did richness which correlated loss richness. Community differed between small large reefs, without kelp, at centre edge within supporting low Overall, results indicate complex decline communities, dense stands, areas that dominated turf algae. While standing from rocky result declines biodiversity, algae replaces still productivity.