Sara Barrientos

Biotic multipliers of global change: herbivory pressure on kelp forests (visiting PhD 2019)

I am visiting PhD student from the University of Coruña, Spain. My PhD research plan focuses in the effects of global change on the distribution and abundance of seaweeds, paying special attention to changes in herbivory pressure in kelp forests.

Global change is tropicalizing temperate ecosystems. Its drivers are many, but its is increasingly perceived that they go beyond a simple physiological effect of warming. Warming also alters species interactions, and its consequences are sometimes magnified along trophic chain. In marine ecosystems, the rocky reefs of temperate latitudes are characterized by an abundance of large brown seaweeds (kelps). Among the various disturbances altering kelp forest, recent studies elsewhere detected that global change sometimes enhances herbivory pressure. Moreover, in extreme cases, the herbivores decimate the patches of foundation seaweeds, causing a phase shift from kelp forest to structurally simpler turf-communities. Thus, herbivores act as biotic multipliers of global change causing disproportionate community changes through their impact on fundation species.

My project at the UWA Oceans institute in Werberg Lab aims to compare the vulnerabilty of the kelp Ecklonia radiata with other species of macroalgae also present in the temperate subtidal through a multiple-choice feeding preference experiment in the field with temperate and tropical herbivorous fish. Moreover, the results obtained will allow a comparison between Atlantic and Indian Ocean.

Supervisors: Rodolfo Barreiro Lozano (University of A Coruña), Cristina Piñeiro Corbeira (University of A Coruña), Thomas Wernberg.