Dr Ohad Peleg1, Dr Caitlin Blain1, Dr Nick Shears1
1University Of Auckland, Leigh, New Zealand
Trophic downgrading destabilises ecosystems and can drive large-scale shifts in ecosystem state. While restoring predatory interactions in marine reserves can reverse anthropogenic-driven shifts, empirical evidence of increased ecosystem stability and persistence in the presence of predators is scant. We compared temporal variation in rocky reef ecosystem state in New Zealand’s oldest marine reserve to nearby fished reefs to examine whether increased predator abundance led to more persistent and stable reef ecosystem states in the marine reserve. Contrasting ecosystem states were found between reserve and fished sites, and this persisted over the 22-year study period. Fished sites were predominantly urchin barrens but occasionally fluctuated to short-lived turfs and mixed algal forests, while reserve sites displayed unidirectional successional trajectories towards stable kelp forests (<i>Ecklonia radiata</i>) taking up to three decades following protection. This provides empirical evidence that long-term protection of predators facilitates macroalgal recovery, resists shifts to denuded alternate states, and enhances kelp forest stability.
Presentation Slides – Ohad Peleg
Biography:
MSc in Marine Biology, University of Haifa (Israel) and Israel Oceanographic & Limnological Research (IOLR), on the effects of tropicalization on southeastern Mediterranean reefs’ carbon budget and trophic state. Supervised by Drs Gil Rilov and Jacob Silverman.
PhD in Marine Science, Leigh Marine Laboratory, Institute of Marine Science, University of Auckland (New Zealand), on assessing reef ecosystem health and stability. Supervised by Drs Nick Shears and Caitlin Blain.
Formerly Lab Manager and Research Assistant to Dr Gil Rilov at IOLR (Israel).
Currently, Research Assistant to Dr Nick Shears
