Graeme Guy

Ms.c. Student

Current research

The dispersal of marine organisms across seascapes is a key process in maintaining biodiversity and population persistence. Patterns of larval dispersal and connectivity within a spatially fragmented population can be used in combination with graph theory metrics to identify critical habitat patches for the persistence of a metapopulation. My research focuses on understanding these patterns for the habitat forming deep-water coral, Lophelia pertusa, in the Northwest Atlantic Ocean. I am using a 3-D Lagrangian particle tracking model coupled with an ocean circulation numerical model to simulate larval dispersal through space and time. Using these tracks, I aim to identify habitat patches critical for the overall connectivity of L. pertusa in the region. Early results show strong seasonal and interannual variability in connectivity among habitat patches which suggests the timing and duration of spawning will greatly affect connectivity between populations, variables which are currently unknown for NW Atlantic populations. Results also show that the length of the pre-competency period greatly influences the strength and number of connections across populations. I will calculate several specific connectivity metrics, including closeness centrality, eigenvector centrality, and directionality for current and future climate scenarios, when suitable habitat is predicted to decline due to acidification, deoxygenation, and decreased food availability. My research will help to inform which populations of L. pertusa in the NW Atlantic should be prioritized for climate-smart protection and preservation to optimize the resilience of the network


Dalhousie University, Halifax, NS

Department of Oceanography

MSc Student

September 2020- present

Dalhousie University, Halifax, NS

Department of Biology

Bachelors in Marine Biology with Honours

September 2017 – April 2020

Publications & Reports

Guy G, Metaxas A (2022) Recruitment of deep-water corals and sponges in the Northwest Atlantic Ocean: implications for habitat distribution and population connectivity. Mar Biol 169:107. doi: 10.1007/s00227-022-04089-w

Guy G, Metaxas A (2020) Analysis of Seabed Video Imagery from 2019 Okeanos Explorer Research Cruise. (Technical Report for Fisheries and Oceans Canada)

Scholarships & Awards

Best Master’s Oral Presentation, Conference for Dalhousie Oceanography Students (2021)

NSERC Canadian Graduate Masters Scholarship (2020-2021)

Faculty of Graduate Studies Entrance Scholarship, Dalhousie University (2020)


Guy G, Metaxas A (2021) Recruitment of deep-water corals and sponges on the continental slope off Nova Scotia, Canada: Implications for population connectivity and conservation. Oral presentation. (16th Deep Sea Biology Symposium)

Guy G, Metaxas A (2021) Recruitment of deep-water corals on the continental slope off Nova Scotia: Implications for habitat distribution and population connectivity. Oral presentation. (Conference of Dalhousie Oceanography Graduate Students; Best Master’s Oral Presentation).

Guy G, Metaxas A (2020) Insights into the recruitment of deep-water corals on the continental slope: implications for conservation. Poster presentation. (Dalhousie Cameron Conference)

Other Relevant Experience

Editor Current Tides Magazine: Volumes 5 & 6, Dalhousie University (2020-present)

Event Organizing Team Conference for Dalhousie Oceanography Graduate Students, Dalhousie University (2021)

Teaching Assistant Dalhousie University – Deep Sea Biology (2020)

Deep-Sea Megafauna Video Analyst Fisheries and Oceans Canada, Bedford Institute of Oceanography (2019-2020)


Twitter: @GTW_Guy