RESTORATION on the gsr
Australian researchers are working at the global forefront of marine habitat restoration, with projects underway in every state along the Great Southern Reef. Habitat restoration is a resource intensive exercise used as a last resort for areas where vital habitats have been lost or are in decline and natural recovery is not occurring. Currently there are active restoration projects on the GSR working to restore seaweeds, seagrasses, and oyster reefs.
golden kelp
Golden kelp (Ecklonia radiata), forms the backbone of the Great Southern Reef and is distributed throughout the entire 8,000km range of this interconnected temperate reef system.
However, in Victoria's Port Phillip Bay, the ecosystem has been under siege. Sea urchins, flourishing due to an imbalance in the food chain, have overgrazed 60 percent of the reefs, decimating the once widespread kelp and seaweed habitat.
This ecological crisis can be traced back to the 1980s when excess nutrients from wastewater treatment plants led to a surge in weedy seaweed, a primary food source for purple sea urchins. During the millennium drought, fewer nutrients entered the bay and seaweed growth reduced, so the urchins began eating kelp and seaweed growing on the reefs.
port phillip bay Golden Kelp restoration project
Scientists at the Queenscliff Marine Science Centre have been growing juvenile Golden Kelp in the lab on twine and gravel, ready for replanting in targeted areas. The researchers have grown over 6 million juvenile spores onto twine or embedded in gravel pellets. These trials aim to research and develop the most effective methods for golden kelp cultivation and restoration in the bay, setting the stage for future large-scale efforts.
A key component of the project involves managing the overabundant Purple Urchin populations that have contributed to the creation of barren rocky reefs, devoid of kelp. By reducing urchin numbers to sustainable levels, the team is working to restore balance in the ecosystem, allowing kelp and other seaweeds to recover and thrive once again.
This collaboration involves The Nature Conservancy, the University of Melbourne, Deakin University, and Parks Victoria, and is supported by the Victorian Government.
golden kelp seedBank
In addition to cultivating kelp, researchers are establishing Victoria's first Golden Kelp seedbank at Deakin's Queenscliff Marine Science Centre. This seedbank will preserve the genetic diversity of Golden Kelp, ensuring its resilience and long-term conservation. Collected from various locations around Port Phillip Bay, reproductive material will provide crucial resources for future restoration efforts, and the seedbank is being expanded to include sites along Victoria’s coastline.
Green Gravel
Green Gravel, a concept that integrates restoration ecology with the natural process of seaweed reproduction, offers an impressive potential for the restoration of kelp forests on a large scale. The method is simple yet ingenious: marine substrates or 'gravel' are seeded with juvenile seaweeds, which are then scattered across degraded marine habitats.
As GSRF science committee member Melinda Coleman explains, "The green gravel technique harnesses the microscopic life stage of kelp, which is very easy to manipulate and grow in the lab onto small rocks or gravel." This technique, beyond its simplicity, provides an opportunity for customisation and scalability in marine restoration efforts. Scientists can rapidly seed any kelp genotype onto these rocks, enabling them to populate both degraded and existing kelp communities efficiently.
In the face of rapid environmental changes and the alarming impacts of climate change, marine conservation must transition from a reactive to a proactive approach. We must anticipate future ocean conditions rather than only managing for today's conditions, and Green Gravel facilitates this forward-thinking approach. This innovative and versatile technique broadens the potential for large-scale marine restoration, making it more accessible to a broader range of community members and the public.
By employing green gravel, we can explore the potential for "future-proofing" our marine habitats. This involves boosting the thermal resilience of seaweed populations, particularly vital for sessile organisms that cannot move in response to changing conditions. As such, the technique allows for the selection and seeding of thermally tolerant kelp genotypes, which can better withstand the warmer temperatures anticipated with climate change.
Giant Kelp
Giant kelp (Macrocystis pyrifera) is an iconic canopy forming seaweed that can grow over 35 metres long and up to half a metre each day. Scientists estimate that giant kelp forests have declined over 95% in Tasmania since the 1940′s. In 2012, giant kelp forests became the first marine community to be listed as a threatened ecological community under the Australian Federal Government Environment Protection and Biodiversity Conservation Act.
The main culprit for giant kelp loss is the combination of high temperatures and low nutrients. Giant kelp is highly sensitive to temperature changes and requires lots of nutrients to sustain its rapid growth, particularly under warm conditions. During warm summers giant kelp becomes physiologically impaired, making it more susceptible to diseases and mortality.
Climate change has exacerbated this challenge, transforming the oceanic conditions around Tasmania. The East Australian Current (EAC) is a warm water, nutrient poor current. The EAC is flowing further south than it did previously, displacing much of the cool nutrient rich water typical of the East coast of Tasmania. These changes are largely due to climate change. This warm, nutrient poor water is causing the giant kelp forests to suffer.
Yet, there's hope on the horizon. Scientists are now focusing on resilience as a key factor in the restoration of these kelp forests. By collecting kelp spores from remaining wild populations, scientists are able to culture and store huge quantities of kelp babies in the laboratory that can then be transplanted back onto the reef to restore and rebuild giant kelp forests, from where they have been lost. This innovative approach offers a promising avenue for the future of Tasmania's giant kelp forests in a rapidly changing climate.
Operation Crayweed
Initiated by the Sydney Institute of Marine Science in collaboration with the University of New South Wales, Operation Crayweed stands as a remarkable testament to the power of restoration in marine environments.
The project, which began in 2011, is dedicated to reviving the once-thriving forests of crayweed (Phyllospora comosa) along the Sydney coastline. Unfortunately, these underwater forests suffered severe devastation over the years due to pollution from inadequately treated sewage effluents, especially between the 1970s and 1990s.
Crayweed plays a crucial role in the marine ecosystem, providing a habitat and nursery grounds for various marine species, including ones of economic importance. The loss of these crayweed forests led to a significant reduction in local biodiversity and resilience of the marine ecosystems.
Operation Crayweed has made it its primary mission to restore these vital habitats by transplanting healthy crayweed from unaffected areas to the degraded ones. Led by the esteemed Professor Adriana Verges from UNSW, this monumental restoration effort has achieved remarkable successes thus far, with the newly introduced crayweed not only surviving but also actively reproducing. This inspiring progress signals the Great Southern Reef's potential to heal when provided with the right interventions.
As GSRF Scientific Committee member Professor Adriana Verges expressed, "This is a species that hasn't been here for 30 years and now it is. So that is incredibly rewarding." The dedication and perseverance of the team behind Operation Crayweed have yielded results that highlight the possibility of reversing ecological damage and demonstrate the importance of conservation in strengthening the resilience of Australia's magnificent Great Southern Reef.
As Operation Crayweed continues to pave the way for marine restoration, it serves as an inspiring example for similar initiatives worldwide. It symbolises the potential for reversing ecological damage, underscoring the importance of conservation and reinforcing the resilience of Australia's magnificent Great Southern Reef.
“I have always been interested in understanding the processes by which nature can withstand shocks and recover from shocks.”
- Professor Sean Connell
Oyster Reefs
Australia's coastline was once fringed with oyster reefs, particularly dominated by the native flat oyster (Ostrea angasi), spreading across 1500km of coastline. However, destructive fishing practices by European settlers annihilated these complex and biodiverse seafloors, leaving the native oyster reefs functionally extinct.
The Nature Conservancy Australia is leading the nation's largest marine restoration initiative, focusing on rebuilding Australia's lost shellfish reefs, which have suffered from decades of commercial dredging, pollution, and overfishing. Less than 10% of these vital ecosystems, once home to billions of oysters and mussels, remain. The ambitious Reef Builder project aims to restore 60 shellfish reefs across Australia, making the nation the first in the world to recover a critically endangered marine ecosystem.
Conducted across a 20 ha oyster reef restoration site in southern Australia, local researchers joined forces with the Australian Ocean Lab (AusOcean) to pioneer the use of self-made speakers. These speakers were designed to broadcast the soundscapes of healthy reefs, coupled with artificial kelp to suppress competitive species, creating an environment conducive to oyster growth. The innovative approach led to a marked increase in oyster recruitment, showcasing the potential of integrating acoustic technology with ecological insights. This synergistic method not only offers a promising avenue for revitalising lost oyster reefs but also symbolises a broader commitment to environmental restoration and conservation in Australia.
The project's ambitions extended beyond ecological restoration; it also sought to foster public engagement and awareness. Professor Sean Connell, a member of the GSRF scientific committee, emphasised the human aspect of restoration, stating, "Restoration and conservation is probably as much about people as it is about nature. And we've got to bring people along.” He expressed enthusiasm for the natural recruitment from the functionally extinct ecosystem, highlighting the phenomenal achievement of rebuilding without relying on aquaculture facilities. This blend of scientific innovation and community involvement underscores a holistic approach to restoration, weaving together technology, ecology, and public participation.
Razorfish Reefs
Razorfish are bivalve mollusks that inhabit shallow marine waters around the world. Often overlooked or simply seen as a hazard, these large mollusks can play an important role as ‘ecosystem engineers’ in marine environments. Thanks to their ability to attach themselves to the seafloor, razorfish are able to provide a stable substrate that other species can colonise. Over time they can become decorated in a variety of organisms such as barnacles, hydroids, and algae which can then provide food and shelter for a diverse array of invertebrates and fish.
Through years of observations, Kangaroo Island Landscape Board Project Manager Paul Jennings started to realise that without razorfish we probably wouldn’t have native oysters occurring in the waters around Kangaroo Island. From a serendipitous encounter at a cafe in Kingscote, Jennings met ceramicist Jane Bamford who was working on another restoration project at the time. “We got to talking about native oysters and started to explore ideas about how we could potentially re-create this habitat.”
In this new ground-breaking collaborative design approach to restoration, ceramicist Jane Bamford has produced over 1000 ceramic forms in the shape of razorfish. “These handmade ceramic pinna forms are created from different clay bodies, offering different textures and chemical compositions”. Trialling these different clays may identify a preferred substrate mineral composition for Kangaroo Island’s native oysters. The successful techniques may then be scaled up in the future.
Operation Posidonia
Seagrass meadows, particularly those formed by Posidonia australis, are highly productive and biodiverse habitats. They play a crucial role in protecting shorelines from erosion and capturing carbon from the atmosphere. However, coastal development, pollution, and traditional fixed-block-and-chain boat moorings have led to significant declines in Posidonia meadows, creating 'scars' that are unlikely to recover naturally due to the slow growth of the seagrass.
Operation Posidonia calls upon the local community, known as the 'Storm Squad,' to collect dislodged fragments of Posidonia after storms or large tides. These fragments, often viable for re-planting, provide a source of donor material for restoration without harming existing meadows. Anyone using the waterway can contribute to this restoration effort, with drop-off points established for easy collection.
The initiative serves as a model for how community involvement can make a tangible difference in the fight against environmental degradation, reflecting a broader commitment to ecosystem restoration and conservation.
Seeds for Snapper
Seagrasses play a crucial role in the Great Southern Reef, serving as essential habitats and acting as significant stores of blue carbon, surpassing even tropical forests in carbon storage per hectare and over time. To restore these vital underwater ecosystems, the "Seeds for Snapper'' program, a collaborative effort between the South Australian Research and Development Institute (SARDI), The University of Western Australia (UWA), OzFish and dedicated volunteers, focuses on reintroducing seagrass meadows and reclaiming lost areas. Community members are actively encouraged to participate in this meaningful endeavour by collecting and processing seagrass fruits, sowing the seeds into biodegradable sandbags, and distributing them to identified locations for planting. The success of this process has demonstrated the potential for reversing habitat loss and offers a promising model for seagrass restoration throughout Australia.
Starting in 2018 in Cockburn Sound, Western Australia, and expanding to South Australia in 2020, the "Seeds for Snapper" project has been diligently restoring seagrass meadows in these regions. In further efforts to advance seagrass restoration, OzFish has partnered with the University of Tasmania's Institute for Marine and Antarctic Studies (IMAS) to conduct the first-ever seagrass restoration trial in Tasmanian waters. This trial aims to explore various restoration techniques, including broadcast seeding, direct seeding, seed bags, and transplanting clumps of seeds, across different sites with varied sediment nutrient levels. Through these collaborative initiatives, we are making significant strides towards the revitalization of seagrass ecosystems, safeguarding marine life and preserving the ecological balance for future generations.
