TRACKING LONG-TERM CHANGES IN FOOD WEB DYNAMICS LINKED TO PAST SEABIRD INPUTS AT CAPE ST. MARY’S, NEWFOUNDLAND

Cape St. Mary’s Ecological Reserve (Newfoundland and Labrador, Canada) hosts the third-largest and southernmost Northern Gannet (Morus bassanus) colony in North America. The colony occupies ‘Bird Rock,’ a 100m offshore sea stack, and the adjacent mainland cliffs, collectively supporting tens of thousands of breeding birds. Wind-driven transport of ornithogenic material from Bird Rock has previously been shown to enrich a freshwater pond approximately 240m inland, generating nutrient accumulation and ecological restructuring that paralleled the gannet colony’s twentieth-century expansion. This project integrates sub-fossil cladoceran analysis into the existing multi-proxy paleolimnological framework to examine how primary consumers responded to seabird-derived nutrient inputs. Cladocerans, as bioindicators, reveal shifts in food quality, ionic composition, and habitat structure resulting from seabird activity that primary producer proxies alone cannot resolve. By implementing cladocerans as response variables, we can quantify the timing and magnitude of past aquatic community and food web changes in relation to a historically increasing seabird population, which is now considered stable. This approach also helps establish a framework for predicting ecological responses to long-term changes in seabird activity, thereby enhancing our understanding of seabird-driven ecosystem processes in coastal freshwater systems. 

Presentation Preference: Standard Oral (12 Minutes)

Primary Presenter: Zoe Kane, Queen's University (16zak2@queensu.ca)

Authors:

Zoe Kane, Queen's University  (16zak2@queensu.ca)

Matthew Duda, Queen's University  (mattpduda@gmail.com)

John Smol, Queen's University  (john.smol@queensu.ca)

Kathryn Hargan, Memorial University  (kathrynhargan@gmail.com)

Johanna Bosch, Memorial University  (yohannabosch@gmail.com)