Ecosystems engineers (e.g. kelps, bivalves, mangroves and saltmarshes) form structurally complex habitats. However, the abundances of these species are declining around the world and in Australia. In Port Phillip Bay it has been estimated that >90% of the bivalve reefs (oysters and mussels) and kelp forests have been lost due to human impacts. Loss of these key habitat-forming species can severely limit how temperate reefs perform ecologically important functions. This has flow on effects for the provision of services valued by humans, such as biodiversity including economically important fished species and recreation.
In the habitat restoration group, we aim to control the factors leading to the degradation of bivalves and kelps in Port Phillip Bay and elsewhere in Victoria. We are also developing new techniques and mechanisms to restore these important habitat-forming species in degraded habitats.
Project 1: Urchin Management
Overabundant local and range-expanding native sea urchins present an ever-increasing threat to kelp forests in Victoria. Currently there is little understanding of the scale of the problem, what management actions are most appropriate and where they should be targeted. This project will trial different approaches to sea urchin management, including the feasibility and effectiveness of different culling methods. The research will fill key knowledge gaps in urchin ecology to improve management outcomes, as well as expanding and up-scaling sea urchin culling trials across the state. The data from the project will then be used to estimate the cost benefits of different urchin management approaches and their suitability for each geographical context to help guide on-going management of sea urchins. This project is funded by DELWP.
People involved: Rituraj Sharma; Rebecca Morris; Beth Strain; Fletcher Warren-Myers; Steve Swearer
Project 2: Kelp Restoration
A loss of kelp forests results in a loss of species that rely on kelp for food and shelter. Restoring degraded kelp forest at barren areas will restore habitat essential to the juvenile and adult stages of many of the Bay’s marine animals, including economically important species such as abalone and rock lobster. In this project we are trialling different techniques for restoring kelp in areas where sea urchins have been removed. The techniques include culturing, and transplanting kelps, and assessing the environment conditions required for juvenile survival and growth. The data will be used to upscale restoration efforts around Port Phillip Bay. This project is funded by DELWP.
People involved: Tristan Graham; Sarucha Suebsanguan; Rebecca Morris; Beth Strain; Steve Swearer
Project 3: Oyster Restoration
Oyster reefs were once a dominant structural and ecological component of embayments across the globe. Whilst there has been significant work undertaken to restore or repair oyster reefs internationally, here in Australia, we are only at the beginning of the journey. The project will test different methods for constructing and restoring subtidal oyster reefs in Port Phillip Bay. The aim of the project is to investigate the potential factors (such as predation and sedimentation) limiting the natural recovery of local native Flat Oyster, Ostrea angasi and thus help guide future restoration efforts. The project is an integral part of the broader collaborative project between Fisheries Victoria, The Nature Conservancy Australia and the Albert Park Yachting and Angling Club.
People involved: Ben Cleveland; Steve Swearer