Publication – slugs this time!

Congratulations to Miranda Dennis, who completed their PhD in Mike Hart’s lab at SFU and Ka’ala Estores Pacheco who completed their MSc with Ángel Valdés at California Polytechnic, Pomona.

The overall finding from the research was that the two North American species of Hermissenda do not interbreed. Miranda’s work was based on genetic sequences that showed both that the two species were distinct and there was little or no gene flow between the two populations. Ka’ala’s work was focused on lab observations of mating behaviour – members of each species were happy to mate with each other, but when pairs were from opposite species, no mating was observed.


Dennis, M.T., Ka’ala Estores‐Pacheco, A.L., Williams, K., Wyeth, R.C., Valdés, Á., Mooers, A.Ø., and Hart, M.W. 2026. Demographic Models and Behavioral Assessments Uncover Distinct Species Histories in the Pseudocryptic Nudibranch Genus Hermissenda. Ecology and Evolution 16(2): e73045. doi:10.1002/ece3.73045.

Lotsa lobster presentations and posters

At the start of November, both Russell and Grace presented talks and both Grace and Ryan presented a poster each as well at the the inaugural North American Lobster Science Symposium. The talks have been share online, so here they are, along with Ryan’s poster.

Grace Walls – Biotic and abiotic influences on American lobster, Homarus americanus, response to bait.

[Video Not Available… ]

Grace Walls – Does the American lobster fishery need a bait testing service to
facilitate change in bait use?

Russell Wyeth, – Influences of prey type on American lobster agonistic behaviours

Ryan Bergman – Juvenile Lobster in the Southern Gulf of St. Lawrence – A Baseline Density & Behavioural
Survey

Publication, and this time on TV too!

Huge congratulations to Grace Walls for getting the first publication from her PhD done. And past students Rachel Webber, Laura Brady, and Michelle Hodgson and many others members of the lobster team as well as all the harvesters who helped with boat time for the project all get a share in the credit.

Published in Fisheries Management and Ecology, this is the first of several planned publications from our lobster bait project. Grace shows that Baited Remote Underwater Video (BRUV) is a viable method to assess baits for lobster fishery. This is important, because it provides a method for refining alternative bait development in advance of testing new baits in the fishery. Our hope is this will contribute to the fishery shifting towards a more sustainable approach to bait use.

One of our local community TV stations interviewed Russell about the work and the larger issue of sustainable bait in the lobster fishery.


Walls, L.G., Webber, R., Brady, L., Hodgson, M., McGaw, I.J., and Wyeth, R.C. 2025. Assessment of a baited remote underwater video method to evaluate American Lobster (Homarus americanus) response to baits in nature. Fisheries Management and Ecology. doi:10.1111/fme.70026.

Publication!

Congrats to Wyeth Lab alumni Areej, Carmen, Hannah and Kero for our latest publication in the Journal of Experimental Biology. Everyone has moved on to other things now, since this one was delayed substantially by the pandemic. They worked over several years, conducting a bunch of experiments on how pond snails navigate in different flow and lighting conditions. In the end, we found the first evidence from any animal of switching between two types of navigation behaviours depending on the flow conditions. In laminar flow, the snails seem to be following chemical gradients (chemotaxis) while in turbulent flow, they are likely following the flow (chemical-gated rheotaxis).

Activity heat maps of slugs navigating in turbulent flow, along with metrics of their movements.

Alansari, A.F., Ucciferri, C.C., Stevens, H., Youssef, K., and Wyeth, R.C. 2025. Navigational behaviour of Lymnaea stagnalis in response to chemical and flow cues. J Exp Biol 228(16): jeb250746. doi:10.1242/jeb.250746. Alternate link for PDF access.

Congratulations MM MSc

Mike Murtaugh successfully defended his MSc thesis earlier in August and has just submitted his final thesis.  His thesis (title: Changes in Biofouling Composition Mediated by a Sub-Optimal UV-C Antifouling Treatment and the Relationship Between Larval Availability and Recruitment) involves two rather independent chapters. The first examines the effect of very low UV dosing on biofouling community composition. The idea was to explore what may happen at the margins of UV antifouling illumination, and what happened, at least sometimes,  was community composition change. The second tracks a number of time series relevant to biofouling community composition: larval abundances in the plankton, young recruits, and later abundances in fouling communities. He found, as expected,  that propagule pressure, settlement, and/or later growth can variably contribute to producing biofouling communities observed in our local waters.  A fantastic achievement!  Next up: Mike is sticking around to complete his PhD, again focusing on a mix of biofouling and antifouling science. 

Helping out with the inaugural X-STEM camp

This year was the first X-STEM camp organized for indigenous and African descent high schoolers here at StFX.   About 30 students came for four days to participate in a variety of STEM related activities. Our role was during the visit to Crystal Cliffs. Lexy ran an  activity focused on animal chemical senses involving candy (instantly popular…).  RyanLiam, and Aidan went snorkeling for juvenile lobsters, and Russell explored the diversity that could be D-netted from the salt water lagoon.  Lots of kids enjoying the outside time and engaged with biodiversity – exactly what we were hoping for.

Payton Plesh

My name is Payton Plesh, and I’m from Barrie, Ontario. I’m heading into my fourth year at St. Francis Xavier University, where I’m working toward an Honours degree in Biology. I’ve always had a strong love for nature and wildlife, and that passion has guided me throughout my studies. Being part of the biofouling project is an exciting opportunity for me to gain hands-on experience and build research skills that will help me in the future as I work toward a career as an animal biologist.