Dr Mariana Mayer Pinto1, A/Prof Melanie Bishop2, Professor Emma Johnston4, Dr Aria Lee3, Dr Tim Glasby5, Professor Laura Airoldi6, A/Prof Katherine Dafforn2
1University Of New South Wales, Sydney, Australia, 2Macquarie University, Sydney, Australia, 3Sydney Institute of Marine Sciences, , Australia, 4The University of Sydney, Sydney, Australia, 5NSW Department of Primary Industries, Port Stephens Fisheries Institute, Taylors Beach, Australia, 6University of Padova, Chioggia, Italy
Marine construction is a major driver of loss of biodiversity and ecosystem functioning, with built infrastructure now impacting over 1 million km2 of seafloor. Ecological (or eco)-engineering is increasingly used to reduce the ecological footprint of marine built infrastructure. Here, we examine the effects of a large-scale intervention on fish and fouling assemblages at an intertidal (mean low water, 0.5 m) and subtidal (-3 m) depth. Habitat enhancing panels were installed on horizontal riggings between the pilings of an overwater boardwalk on the northern and southern end of the embayment at Watermans Cove, Sydney Harbour, Australia. Five different panel designs and one flat control were installed in the embayment. The panel designs were: Rockpool; Oyster colony; Textures (uneven, rough surfaces across the panel); Sponge fingers; and Kelp holdfast. Half of the ‘kelp holdfast panels’ were seeded with live kelp Ecklonia radiata sourced from nearby pilings that were removed for maintenance. The ‘rockpool panel’ was only installed in the intertidal zone while kelp holdfast panels were only installed subtidally. Remote underwater video cameras (RUVs) were used to record the fish activity, number and identity of fish interacting with panels at each depth at two times point (10 and 16 months after installation). Fouling assemblages were also sampled during the same period. We found a total of 24 fish species. The most abundant species overall was Parablennius intermedius. Preliminary results suggest that sponge panels had greater number of fish species than other panel designs, at both intertidal and subtidal depths at time 2. In this talk, we discuss how differences in fouling assemblages across panel designs and depth might influence fish assemblages and the importance of local conditions in the effectiveness of eco-engineering interventions.
Presentation Slides – Mariana Mayer-Pinto
