Dr Dominic McAfee1, Prof Sean Connell1
1The University Of Adelaide, ,
Marine soundscapes provide important navigational cues to dispersing larvae in search of suitable settlement habitat. Habitat restorations can provide suitable substrate for recruitment and habitat growth, but typically occur where soundscapes are degraded and recruitment is limited. To address this restoration bottleneck (insufficient recruitment), we used underwater speakers to enrich marine soundscapes at newly constructed reefs in order to reprovision the navigational highways that organisms use to find a place to live. Across two large oyster reef restorations in South Australia, we deployed speakers at four sites and at three times throughout the recruitment season to test whether soundscape enrichment could boost recruitment and habitat building by oysters. Soundscape enrichment significantly increased oyster recruitment at 8 of the 10 sites by an average 5 times (5,281 ± 1,384 more larvae per m2) and by up to 18 times. After 5 months, the early recruitment of oysters to the newly constructed boulder reefs resulted in more large oysters that built more three-dimensional habitat than non-speaker control reefs. Our results suggest that soundscape enrichment can accelerate the formation of the vertical growth forms that provide the ecological functions that motivate restoration efforts. I will discuss when and where soundscape enrichment is likely to benefit to restoration efforts, such that it may steer the ecological succession on new reefs on a trajectory of desired habitat recovery, potentially reducing the cost of ongoing intervention.
Biography:
My research focuses on the social and ecological restoration of lost marine ecosystems, primarily reef ecosystems formed by oysters and mussels. These reefs have been lost from the seafloor and from public knowledge, both of which require recovery to ensure habitat restorations are both an environmental and social success.
