David Beauchesne

University of Toronto | U of T

The productivity of marine ecosystems and the services they provide to humans are largely dependent on complex interactions between prey and predators. These are embedded in a diverse network of trophic interactions, resulting in a cascade of events following perturbations such as species extinction. The sheer scale of oceans, however, precludes th...

The St. Lawrence is a vast and complex socio-ecological system providing a wealth of services that sustain numerous economic sectors. This ecosystem is subject to significant human pressures that overlap and potentially interact with climate-driven environmental changes. Our objective in this paper was to systematically characterize the distributio...

Evaluating the effects of multiple stressors on ecosystems is becoming increasingly vital with global changes. The role of species interactions in propagating the effects of stressors, although widely acknowledged, has yet to be formally explored. Here, we conceptualise how stressors propagate through food webs and explore how they affect simulated...

The Convention on Biological Diversity is setting ambitious goals for preserving biodiversity, the first of which states that the integrity of ecosystems must be enhanced. This recognizes that biodiversity is not a mere collection of species; it also includes the diversity of interactions driving ecological dynamics and ecosystem functioning. Yet m...

Co-occurring anthropogenic activities influence coastal ecosystems around the world. Notions of ecological exposure are promising indicators to better understand environmental status and enhance ecosystem protection. This study characterized anthropogenic exposure in the context of multiple human activities on coastal benthic ecosystems at a scale...

Anthropogenic influence is a widespread phenomenon affecting coastal ecosystems, the majority of which bears various cooccurring human activities. The exposure and vulnerability of ecological communities and habitats to multiple human activities are promising indicators of the state of coastal benthic ecosystem worldwide. In this study, we develope...

The estuary and the Gulf of St. Lawrence (EGSL), eastern Canada form a vast inland sea that is subjected to numerous anthropogenic pressures. Management tools are needed to detect and quantify their effect on benthic communities. The aims of this study are to analyze the spatial distribution of epibenthic communities in the EGSL and quantify the im...

Indigenous Peoples and Local Communities (IPLCs) have inhabited coastal areas, the seas, and remote islands for millennia, and developed place-based traditional ancestral knowledge and diversified livelihoods associated with the biocultural use of marine and coastal ecosystems. Through their cultural traditions, customary wise practices, and holist...

Global changes are creating intricate stress exposure regimes that induce unpredictable environmental effects permeating entire ecological communities by way of species interactions. The role of species and their interactions in mediating the effects of multiple disturbances on food webs remains understudied. Experimental and in situ approaches pro...

In order to help safeguard biodiversity from global changes, the Convention on Biological Diversity developed a Strategic Plan for Biodiversity for the period 2011-2020 that included a list of twenty specific objectives known as the Aichi Biodiversity Targets. With the end of that timeframe in sight, and despite major advancements in biodiversity c...

Cumulative potential impacts of the stress factors associated with human activities on the St. Lawrence marine ecosystem BY Photo: Pixabay 135 / 134 /-Human activities deriving from the occupation of the shores of the Estuary and the Gulf of St. Lawrence induce stress factors for marine organisms.-The effects on the environment and the organisms of...

A regional assessment of cumulative impacts is required for the Estuary and Gulf of St. Lawrence to facilitate ecosystem based management supported by evidence. The only currently available assessment was performed at the global scale using 19 drivers of anthropogenic stressors such as fisheries and pollution. While valuable, certain datasets inclu...

Describing environmental and anthropogenic drivers of ecosystem change (e.g. hypoxia and fisheries) is largely relying on simplistic metrics that ignore dependencies and the potentially convoluted propagation of effects through complex ecological networks. While informative, such approaches are hardly conducive to robust inference on the impacts of...

Gathering data for large scale, systematic research initiatives such as regional multi-stressor analyses can be a very challenging - not to say painful - process. On one hand, there is an overwhelming wealth of data available, while on the other hand, some required data remain largely unavailable or inaccessible. Coupled with political intricacies,...

Exhaustively describing the complex nature of ecological interaction networks is a challenging task even under ideal conditions. When confronted with data-poor environments and large scales of analyses, the task becomes even more daunting. Network-level descriptors are thus largely ignored for practical applications, even though we recognize the im...

Large networks of ecological interactions, such as food webs, are complex to characterize, be it empirically or theoretically. The former requires exhaustive observations, while the latter generally requires ample data to be validated. We therefore wondered whether readily available data, namely empirically described interactions in a variety of ec...

Large networks of ecological interactions are complex to characterize, be it empirically or theoretically. We therefore wondered whether readily available data could be used to predict species interactions in data deficient ecosystems. To test this, we used an unsupervised machine learning method with empirical pairwise interactions datasets to pre...

L’intensification de l’empreinte humaine dans l’estuaire et le golfe du Saint-Laurent impose une planification systémique de l’exploitation des ressources marines. Une évaluation régionale des impacts cumulés dans le Saint-Laurent demeure pourtant encore attendue. Un nombre important d’activités (p. ex. transport maritime, pêche, aquaculture) carac...

Poster presentation describing my thesis project on the evaluation of the impact of multiple stressors on the structure of communities, defined through biotic interactions, in the estuary and the gulf of St. Lawrence in eastern Canada. Available in French and in English.

Although prey species typically respond to the most limiting factors at coarse spatiotemporal scales while addressing biological requirements at finer scales, such behaviour may become challenging for species inhabiting human altered landscapes. We investigated how woodland caribou, a threatened species inhabiting North-American boreal forests, mod...

Le caribou (Rangifer tarandus) est une espèce particulièrement sensible aux perturbations anthropiques. En utilisant un cadre conceptuel basé sur les différentes échelles biologiques de réponse à une perturbation, nous présentons une revue des connaissances actuelles sur les impacts des routes, chemins et sentiers sur plusieurs facettes de l'écolog...

As human encroachment in natural habitats increases ubiquitously, understanding its impacts on wildlife is crucial. We investigated the impacts of anthropogenic disturbances (i.e. clearcuts and roads) on the movements of the woodland caribou, a threatened species inhabiting the highly managed southern fringe of the boreal forest. We used GPS teleme...