Established non-native species can have significant impacts on native biodiversity without any possibility of complete eradication. In such cases, one management approach is functional eradication, the reduction of introduced species density below levels that cause unacceptable effects on the native community. Functional eradication may be particularly effective for species with reduced dispersal ability, which may limit rates of reinvasion from distant populations. Here, we evaluate the potential for functional eradication of introduced predatory oyster drills (Urosalpinx cinerea) using a community science approach in San Francisco Bay. We combined observational surveys, targeted removals, and a caging experiment to evaluate the effectiveness of this approach in mitigating the mortality of prey Olympia oysters (Ostrea lurida), a conservation and restoration priority species. Despite the efforts of over 300 volunteers that removed over 30,000 oyster drills, we report limited success. We also found a strong negative relationship between oyster drills and oysters, showing virtually no coexistence across eight sites. At experimental sites, there was no effect of oyster drill removal on oyster survival in a caging experiment, but strong effects of caging treatment on oyster survival (0 and 1.6% survival in open and partial cage treatments, as compared to 89.1% in predator exclusion treatments).more »
This content will become publicly available on June 29, 2023
Variation in Survival and Gut Microbiome Composition of Hatchery-Grown Native Oysters at Various Locations within the Puget Sound
ABSTRACT The Olympia oyster ( Ostrea lurida ) of the Puget Sound suffered a dramatic population crash, but restoration efforts hope to revive this native species. One overlooked variable in the process of assessing ecosystem health is association of bacteria with marine organisms and the environments they occupy. Oyster microbiomes are known to differ significantly between species, tissue type, and the habitat in which they are found. The goals of this study were to determine the impact of field site and habitat on the oyster microbiome and to identify core oyster-associated bacteria in the Puget Sound. Olympia oysters from one parental family were deployed at four sites in the Puget Sound both inside and outside of eelgrass ( Zostera marina ) beds. Using 16S rRNA gene amplicon sequencing of the oyster gut, shell, and surrounding seawater and sediment, we demonstrate that gut-associated bacteria are distinct from the surrounding environment and vary by field site. Furthermore, regional differences in the gut microbiota are associated with the survival rates of oysters at each site after 2 months of field exposure. However, habitat type had no influence on microbiome diversity. Further work is needed to identify the specific bacterial dynamics that are associated more »
- Editors:
- Kormas, Konstantinos Aristomenis
- Award ID(s):
- 1837116
- Publication Date:
- NSF-PAR ID:
- 10343199
- Journal Name:
- Microbiology Spectrum
- Volume:
- 10
- Issue:
- 3
- ISSN:
- 2165-0497
- Sponsoring Org:
- National Science Foundation
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