Concordia University
M.Sc. candidate
Supervisor: Nicola Smith
Eric Pedersen
Start: 2026-09-08
End: 2028-08-31

Project

Quantifying evidence for space resource competition between native and invasive predators on Caribbean coral reefs
The Indo-Pacific lionfishes (Pterois volitans and P. miles) are among the most ecologically damaging marine invaders in the Western Atlantic, Caribbean, and Gulf of Mexico. Graysby groupers (Cephalopholis cruentata) are small-bodied, native Caribbean fish that share similar diets and habitat preferences with lionfish, competing with them for prey and habitat. Graysby groupers have demonstrated shifts in diet when lionfish are present; however, it is unclear how the presence of lionfish affects movement behaviours of these native fish, including space use and shelter selection. I aim to investigate whether lionfish presence alters space use of graysby groupers on Bahamian coral reefs. I will select two coral patch reefs surrounding Eleuthera Island for my experiment. I will implant acoustic transmitter tags in groupers and lionfish on both reefs and monitor the movement of tagged fish with underwater microphones for four months. For the first two months, both graysby groupers and lionfish will be present. I will then remove lionfish from one reef and continue monitoring both sites for another two months. By comparing the space use of lionfish and graysby groupers before and after lionfish removal, I can investigate whether lionfish and graysby groupers compete for space on coral reefs. My study will provide further insights into how invasive lionfish impact native predator movement and will support the need for continued lionfish management and coral reef conservation.

Keywords

marine , aquatic ecology, Lionfish, space-use

Publications

1- Long-term changes in three eastern Canadian lake records with different land use histories: a multiproxy study
Aucoin, Madeleine E., Zoë Rabinovitch, Jennifer Pham, David R. Zilkey, Irene Gregory-Eaves
2025 Journal of Paleolimnology

2- Long-term trends in aquatic communities of mesotrophic lakes along a land-use gradient in eastern Canada
King, Leighton, Paul W. MacKeigan, Rebecca E. Garner, Madeleine E. Aucoin, Beatrix E. Beisner, Isabelle Domaizon, John P. Smol, Irene Gregory-Eaves
2026 Anthropocene

3- Temporal dynamics of ecological networks: deciphering changes in cladoceran assemblages over the past ~ 150 years in response to land-use development
Pham, Jennifer, Zofia E Taranu, Madeleine E Aucoin, Zoë Rabinovitch, Cindy Paquette, Beatrix E Beisner, Irene Gregory-Eaves,
2025 Journal of Plankton Research