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Abstract Climate change is causing rapid, unexpected changes to ecosystems through alteration to environmental regimes, modification of species interactions, and increased frequency and magnitude of disturbances. Yet, how the type of disturbance affects food webs remains ambiguous. Long‐term studies capturing ecosystem responses to extreme events are necessary to understand climate effects on species interactions and ecosystem resilience but remain rare. In the Gulf of Mexico, our 8‐year study captured two disturbances that had contrasting effects on predator abundance and cascading effects on estuarine food webs. In 2017, Hurricane Harvey destroyed fishing infrastructure, fishing activity declined, and sportfish populations increased ~40% while intermediate trophic levels that sportfish prey upon declined ~50%. Then, in 2021, a fish kill caused by freezing temperatures during Winter Storm Uri reduced sportfish populations by ~60% and intermediate trophic levels increased by over 250%. Sportfish abundance affected the abundance and size of oyster reef mesopredators. Excluding fish predators significantly altered oyster reef community structure. These results demonstrate how extreme events shape communities and influence their resilience based on their effects on top predators. Moreover, top‐down forces from sportfish are important in estuaries, persist through disturbances, and influence community resilience, highlighting the necessity of proper recreational fisheries management through extreme events.
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This content will become publicly available on November 22, 2025
Fish abundance is enhanced within a network of artificial reefs in a large estuary
Artificial reefs may be created within estuaries for multiple reasons, including habitat enhancement, oyster production, or recreational fishing. While traditional sampling in this environment is difficult due to complex structures and the high turbidity of estuaries, acoustic imaging sonar provides an effective alternative to measure abundance and size spectra of the fish community. We sampled eight artificial reefs in Pamlico Sound, North Carolina, that are designated as oyster sanctuaries. At each oyster sanctuary, we sampled 26 boat positions along two transects using ARIS imaging sonar, which included control areas outside of the sanctuaries over featureless bottom. We found that fish abundance and mean length were greater within the oyster sanctuary boundaries, but did not observe any significant differences among artificial substrate types within the sanctuaries. Further, we found that fish abundance dropped to near background levels within 25 m outside of the oyster sanctuary edge. Size spectra analysis revealed that abundance was higher in the sanctuaries versus control areas for every length bin of the fish community (5 to 50 cm). However, the differences in abundance were greatest for 10 to 30 cm fishes. Our results can be coupled with previous research on species composition data to more fully understand the potential role that the Pamlico Sound oyster sanctuaries, and estuarine artificial reefs in general, serve as habitat and recreational fishing enhancement.
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- Award ID(s):
- 2125684
- PAR ID:
- 10626991
- Publisher / Repository:
- Frontiers
- Date Published:
- Journal Name:
- Frontiers in Marine Science
- Volume:
- 11
- ISSN:
- 2296-7745
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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