Mentor/s
Dr. LaTina Steele
Participation Type
Poster
Abstract
Hemigrapsus sanguineus (Asian shore crab) is an invasive crustacean that often outcompetes established species on the eastern seaboard and impacts biodiversity. Although it can have detrimental effects, the H. sanguineus population at a marsh restoration site at Stratford Point, Connecticut has declined since 2019. Understanding predation dynamics on Asian shore crabs can provide insights into the mechanisms driving this decline. We conducted a mark-recapture study to estimate H. sanguineus population size at Stratford Point as part of ongoing monitoring, yielding an estimated 33,913 crabs at the site in 2023, a 25% decline from 2022. A tethering experiment confirmed that marking did not increase odds of predation. To examine diurnal and tidal effects on predation on H. sanguineus, we performed two tethering experiments comparing crab survival 1) during the day and at night and 2) during high and low tide. Although Chi square tests showed no significant diurnal or tidal effects on crab survival, more research is needed to fully understand the dynamics present in these ecosystems and why this population continues to decline. We expect these trends to continue as the restored marsh matures, since previous work showed higher predation rates in vegetated vs. unvegetated areas at the site.
College and Major available
Coastal & Marine Science
Location
Digital Commons & West Campus West Building University Commons
Start Day/Time
4-26-2024 12:00 PM
End Day/Time
4-26-2024 2:00 PM
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License
Patterns of Predation in a Declining Asian Shore Crab Population at a Marsh Restoration Site
Digital Commons & West Campus West Building University Commons
Hemigrapsus sanguineus (Asian shore crab) is an invasive crustacean that often outcompetes established species on the eastern seaboard and impacts biodiversity. Although it can have detrimental effects, the H. sanguineus population at a marsh restoration site at Stratford Point, Connecticut has declined since 2019. Understanding predation dynamics on Asian shore crabs can provide insights into the mechanisms driving this decline. We conducted a mark-recapture study to estimate H. sanguineus population size at Stratford Point as part of ongoing monitoring, yielding an estimated 33,913 crabs at the site in 2023, a 25% decline from 2022. A tethering experiment confirmed that marking did not increase odds of predation. To examine diurnal and tidal effects on predation on H. sanguineus, we performed two tethering experiments comparing crab survival 1) during the day and at night and 2) during high and low tide. Although Chi square tests showed no significant diurnal or tidal effects on crab survival, more research is needed to fully understand the dynamics present in these ecosystems and why this population continues to decline. We expect these trends to continue as the restored marsh matures, since previous work showed higher predation rates in vegetated vs. unvegetated areas at the site.
Students' Information
Keith McGann, Coastal and Marine Science, 2025