Oyster study findings support reef restoration trial

Council has welcomed the results of The Nature Conservancy’s study into Noosa River oyster species.

The conservation group’s findings could pave the way, says Noosa Council environment officer Jan Maddin, for an oyster reef restoration project to enhance biodiversity in the estuary.

Oyster reefs were once abundant in the Noosa River forming an important part of a healthy aquatic ecosystem, providing habitat and a rich food source for fish and other marine life.

“This study found that oysters grew in moderate numbers at all of 12 Noosa River estuary test sites, with a couple of those sites recording high rates of spawning,” Ms Maddin said.

“This is great news, as oyster reef restoration efforts in waterways where oysters are still naturally occurring is easier to achieve, as you don’t require supplemental oyster larvae from a hatchery.”

For the study, the Nature Conservancy deployed  more than 160 tiles or plates in Noosa River estuary and monitored them over five months to find out what oyster species grew on the tiles and if some locations in the estuary were better than others for oyster spawning.

Council jointly funded the study with The Thomas Foundation.

The Thomas Foundation is a philanthropic organisation established by David Thomas and his late wife Barbara. In recent years the Foundation has focused on marine conservation, initiating the Great Southern Seascapes program led by The Nature Conservancy. Oyster reefs, sea grasses and other natural features of major estuaries and bays in Melbourne, near Adelaide and in Western Australia are being restored under the program which is strongly supported by governments, universities, recreational fishing clubs, corporates and other private funders. 

Ms Maddin said the Noosa River Nature Conservancy study provided important research to help inform any future oyster reef restoration project.

“Surprisingly the study didn’t show Sydney rock oysters spawning on the tiles despite numerous rock oysters growing on hard engineered surfaces such as pylons, jetties and seawalls within the estuary,” Ms Maddin said.

“These species are known as the ‘reef-builders’ so it may be they spawn at other times during the year outside this study’s timeframe of December to May.

Council’s Planning and Infrastructure Director Martin Drydale said Council was pleased to partner with both The Thomas Foundation and The Nature Conservancy for the study.

“And we hope to continue this relationship with a future oyster reef pilot trial, which is a natural extension of the work done so far,” he said.

23 October 2015