Oyster aquaculture is one of several methods for the restoration of Delaware Inland Bays; however, little is known about its potential impacts on the benthic community of the bays. In this study, water quality parameters were measured and polychaetes were collected from 24 sampling locations at Rehoboth, Indian River, and Little Assawoman Bays from July to October 2016 and 2017. We aimed to assess the impact of Eastern oyster farming under different stocking densities (50 and 250 oysters/gear) and distances away from the sites where the off-bottom gears are implemented (under gears, one meter, and five meters away). No significant impact was detected on polychaetes’ abundance and richness in regard to the presence of oyster gears. The number of polychaetes and species richness was significantly higher in Little Assawoman Bay in comparison to the Indian River and Rehoboth Bays. Results showed that the Ulva lactuca bloom that happened in 2016 could negatively impact the low abundance and richness observed in the polychaetes community. Similarly, the values of polychaetes abundance and species richness did not change significantly in samples that were taken far from the oyster gears. Dominant polychaetes families were Capitellidae and Glyceridae contributing to more than 70% of polychaetes’ number of individuals. Our results help to understand the role of oyster aquaculture in restoring the viability in the natural habitat of the Delaware Inland Bays.
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Assessing the Biological Performance of Living Docks—A Citizen Science Initiative to Improve Coastal Water Quality through Benthic Recruitment within the Indian River Lagoon, Florida
Like many estuaries worldwide, the Indian River Lagoon (IRL), has seen a decline in resources and overall water quality due to human activities. One method to help restore water quality and benthic habitats is to construct and deploy oyster restoration mats on dock pilings, known as the Living Docks program. This community-driven program was founded to promote the growth of filter-feeding benthic organisms and improve local water quality. The purpose of this study was to assess the growth and performance at four of the Living Dock locations and to provide feedback to the citizens who were involved in the initial process and deployments. Four docks were biologically assessed for temporal changes during three-time points throughout the year, as denoted by changes in temperature in October, February, and June. The back of each mat was also analyzed for organism cementation to the piling. The presence of filter-feeding organisms was found to vary both spatially and temporally, especially for the eastern oyster (Crassostrea virginica), encrusting bryozoan (Schizobrachiella verrilli), sponges (Demospongiae), and barnacles (Amphibalanus amphitrite, Amphibalanus eburneus). A greater diversity in the sessile benthic flora and fauna was seen during the June sampling period. Cementation on the pilings was due to a combination of barnacles and sponge growth. Cementation was observed to increase from October and decrease for all but one dock for the June sampling period. The results demonstrate this restoration project to be successful in promoting the growth of benthic organisms, while also providing understanding into seasonal trends amongst species. Hopefully, the positive output will encourage more community members and citizen scientists to participate in the ongoing effort to help restore water quality in the IRL.
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- Award ID(s):
- 1950768
- PAR ID:
- 10561345
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Journal of Marine Science and Engineering
- Volume:
- 10
- Issue:
- 6
- ISSN:
- 2077-1312
- Page Range / eLocation ID:
- 823
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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