razorfish to the rescuE
A Ceramic Solution to Restore Kangaroo Island's Native Oyster Populations
From abundance to scarcity
Native flat oysters were once abundant in the waters surrounding Kangaroo Island. These oysters, known as angasi oysters were once an important food source for the Indigenous people, who harvested them using traditional methods for thousands of years. However, with the arrival of European settlers in the 19th century, the oyster populations began to decline rapidly due to overfishing, habitat destruction, and the introduction of non-native species.
Hope and hurdles
In the early 20th century, efforts were made to restore the native flat oyster populations of Kangaroo Island’s waters. While these efforts were initially successful, the oyster populations continued to face numerous challenges, including disease outbreaks, predation, and environmental degradation.
An unlikely hero
Today, the native flat oyster populations in Kangaroo Island’s waters remain low, and the oysters are considered a threatened species. But there is new hope for their survival and prosperity, as local marine scientists and oyster farmers have discovered an unlikely hero - razorfish.
Ecosystem engineers
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 colonize. 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.
Razorfish to the rescue
Kangaroo Island Landscape Board Project Manager Paul Jennings has long admired the ecosystem engineering capabilities of razorfish. Throughout years of observations he 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.”
Art meets science
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”. Trialing 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.
Seeding success
KI Landscape Board Coasts Project Officer Alexandra Comino said “every summer the small population of native angasi oysters surrounding Kangaroo Island release millions of larvae into the waters. It’s hoped that once the oyster reefs are seeded and established, they will continue to grow as native oysters are extremely gregarious, meaning they actively seek out habitats where other oysters live during the larval stage before settlement,”
Reviving the reef
The ceramic razorfish forms have been installed by hand on their new reefs among seagrass meadows and other artificial reef structures this summer, coinciding with the angasi spawning period. These efforts are crucial not only for the survival of the native flat oysters, but also for the health and resilience of the entire marine ecosystem in Kangaroo Island waters. The reefs will have dual benefits, providing important habitat for recreational and threatened fish species, such as King George whiting and Southern calamari, pipefish and seadragons,
Beyond beauty
Bamford is no stranger to out-of-the-box thinking for restoration projects and in recent years has also created ceramic penguin nesting modules for little penguins on KI and artificial spawning habitats for critically endangered spotted handfish in Tasmania. Her innovative work highlights the important role that artists and creative professionals can play in scientific research and conservation efforts, demonstrating the power of interdisciplinary collaboration in finding solutions to complex environmental challenges.'
This project has been assisted by the Australian Government through the Australia Council, its arts funding and advisory body.
The University of Tasmania School of Creative Arts and Media supported Jane Bamford's artist in residency.
Imagery of angasi oysters by Yvonne Young | The Oyster Province
Studio Imagery of razorfish forms by Peter Whyte Photography
Video by Stefan Andrews | Ocean Imaging
