The Wandering Mussels: Analyzing the Ecological Impact of Dreissenid Mollusks Across Spatial and Temporal Scales in Eastern Ontario Using Environmental DNA
type: CreativeWork
description: Biological invasions profoundly disrupt aquatic ecosystems, yet predicting their long-term trajectories remains challenging. To address this, I propose the Alien Succession Hypothesis (ASH), a novel theoretical framework conceptualizing biological invasions as a form of ecological succession arrested by continued ecosystem disturbance, and the dynamics of invasive species interactions as phase and density dependent. I apply ASH to investigate the ecological consequences of dreissenid mussel invasions using environmental DNA (eDNA). Temporally, I tracked quantitative dynamics via qPCR and ddPCR on bloom forming cyanobacterial species and toxin producing genes using high-resolution sedimentary eDNA chronologies. Reinforced by spatial and temporal comparisons, these analyses revealed a correlation inversion between cyanobacterial concentrations and toxigenic potential from eutrophication to dreissenid invasion in the Bay of Quinte. During early eutrophication, low herbivory pressure drove a negative correlation between general Microcystis abundance (16S rRNA) and the toxigenic mcyE gene. Following the dreissenid invasion, intense selective grazing exerted high herbivory pressure, shifting this dynamic to a positive correlation toward toxigenic dominance. Expanding from these targeted analyses, my broader sedimentary community sequencing revealed successive failures of native biotic resistance in the Bay of Quinte. Pre-invasion eutrophication depleted obligate aerobic nutrient-cyclers, establishing a deep-anaerobic fermentative network. The subsequent dreissenid invasion circa 1990 catalyzed a compounding meltdown; mussels restructured the benthic microbiome by depleting historical taxa and uniquely enriching complex-polysaccharide fermenters that exploit nutrient-dense biodeposits. Spatially, I mapped the terminal, saturated stage of the hypothesis using Integrated Species Distribution Models (ISDMs) coupled with contemporary eDNA sampling across Eastern Ontario. These…
abstract: Biological invasions profoundly disrupt aquatic ecosystems, yet predicting their long-term trajectories remains challenging. To address this, I propose the Alien Succession Hypothesis (ASH), a novel theoretical framework conceptualizing biological invasions as a form of ecological succession arrested by continued ecosystem disturbance, and the dynamics of invasive species interactions as phase and density dependent. I apply ASH to investigate the ecological consequences of dreissenid mussel invasions using environmental DNA (eDNA). Temporally, I tracked quantitative dynamics via qPCR and ddPCR on bloom forming cyanobacterial species and toxin producing genes using high-resolution sedimentary eDNA chronologies. Reinforced by spatial and temporal comparisons, these analyses revealed a correlation inversion between cyanobacterial concentrations and toxigenic potential from eutrophication to dreissenid invasion in the Bay of Quinte. During early eutrophication, low herbivory pressure drove a negative correlation between general Microcystis abundance (16S rRNA) and the toxigenic mcyE gene. Following the dreissenid invasion, intense selective grazing exerted high herbivory pressure, shifting this dynamic to a positive correlation toward toxigenic dominance. Expanding from these targeted analyses, my broader sedimentary community sequencing revealed successive failures of native biotic resistance in the Bay of Quinte. Pre-invasion eutrophication depleted obligate aerobic nutrient-cyclers, establishing a deep-anaerobic fermentative network. The subsequent dreissenid invasion circa 1990 catalyzed a compounding meltdown; mussels restructured the benthic microbiome by depleting historical taxa and uniquely enriching complex-polysaccharide fermenters that exploit nutrient-dense biodeposits. Spatially, I mapped the terminal, saturated stage of the hypothesis using Integrated Species Distribution Models (ISDMs) coupled with contemporary eDNA sampling across Eastern Ontario. These…
author: Tian, Haolun
language: eng
keywords: eDNA, sedaDNA, Environmental DNA, Sedimentary DNA, SDM, Niche Modelling, Zebra Mussel, Quagga Mussel, Algal Bloom, Microcystis, Cyanobacterial Algal Bloom, Sediment Microbiome, Bay of Quinte, Eastern Ontario, Metabarcoding, ddPCR, qPCR
license: http://creativecommons.org/licenses/by-nc-nd/4.0/
date modified: 2026-07-27T20:35:43Z
provider: Queens University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Queens University

PropertyValue
property ID: Handle
value: https://hdl.handle.net/1974/36543