In Australia, the native flat oyster, Ostrea angasi, has been reduced to less than 1% of its historical distribution since European arrival. In recent years, restoration efforts have focused predominantly on subtidal zones. However, there is considerable evidence that these oysters were also prevalent in the intertidal zone where they may have impacted the coastal protection of shorelines. To successfully restore these oysters in the intertidal zone we first need to understand their fundamental niche. This study exposed juvenile oysters to different elevations and temperature gradients across locations with varying wind conditions. Juvenile oysters were monitored for 9 months to understand their growth and survival under different conditions.
Across all sites, temperature and inundation duration emerged as a consistent driver of the flat oyster’s fundamental niche. However, the data did show that the realized niche varied by site, which demonstrated the limitations of relying solely on microclimate to define habitat suitability. To optimize restoration efforts, there is room for manipulating the microclimate of the oyster to increase the span of suitable areas, however, site-specific considerations need to be made, such as predation and sedimentation.