Rise of the Turfs: Unlocking the secrets of our Changing Reefs

Following multiple COVID-19 enforced delays, we finally headed to Lizard Island Research Station, in the northern Great Barrier Reef in late March for my project to characterise the microbes of turf algae. This project was made possible by the 2020 Raymond E. Purves Foundation Postdoctoral Fellowship. 

Turf algae or turf refers to the fast growing carpet like multi-species assemblages of filamentous benthic algae, including macroalgae and cyanobacteria, that are typically less than 1 cm in height.  As turf-dominated reefs are likely to be more prominent under a changing climate, it’s important that we understand what sort of role these turfs will play in shaping future coral reef and other ecosystems. 

In marine ecosystems, one of the most striking impacts of climate change is the tropicalisation of temperate reefs, where warm-water species such as tropical fish and reef-building coral shift poleward to waters typically considered temperate, and cool-water species like kelp recede. This leads to the emergence of turf-dominated, economically less-desirable systems. If these turf-dominated systems are the resilient ecosystems of the future, detailed characterisation of their functional ecology and potential ecosystem services is urgently needed. The aim of this project is to characterise turf-dominated communities and the biological and environmental factors leading to their success across a latitudinal gradient along Australia’s east coast.

During our trip we will be SCUBA diving to collect samples for turf microbes, as well as using an underwater pump to collect detritus and sediment samples to determine the nutritional contribution of the benthos. We will also be looking at predation by running a predator-predator assay underwater, as well as using some custom-built incubation chambers for productivity measurements of turf. This research forms part of a larger tropicalisation project, and represents the northern most sites for this work, which will be conducted along a latitudinal gradient off the East coast of Australia.

I am very grateful for the LIRRF Fellowship opportunity made possible through the generous contributions of the Raymond E. Purves Foundation.

Arrival by charter plane from Cairns to Lizard Island. Pictured L-R: Mike Sutherland, Derrick Cruz, Paula Sgarlatta and Steph Gardner

Loading the SCUBA diving gear onto the boat at the start of the day.

Underwater incubation chambers being deployed by Mike, at Granite Bluff, Lizard Island, while Paula prepares nutrient samples on board Freya.

The first flight over the Lizard Island lagoon upon arrival.