Dr. Craig F. Purchase

Evolutionary Ecology of Fishes

Research Program

















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Twitter: @CraigPurchase


Academic synopsis


Memorial University

    Professor of Biology

    Cross-appointed to Dept. of Ocean Sciences

    Cross-appointed to School of Fisheries

    Cognitive & Behavioural Ecology Graduate Program

    Environmental Science Graduate Program


Visiting Professor, University of Western Australia


Associate Professor, Memorial University


Assistant Professor, Memorial University


NSERC Visiting Fellow,

Fisheries and Oceans Canada – Northwest Atlantic Fisheries Centre 


Research Scientist,

Fisheries and Oceans Canada – Bedford Institute of Oceanography


Lecturer, Saint Mary’s University


Sessional Instructor, Dalhousie University


NSERC Postdoctoral Fellow, Dalhousie University


Doctor of Philosophy, University of Toronto


Master of Science, Memorial University


Bachelor of Science (Honours), Memorial University




Other appointments


Past-President, President, VP: Canadian Aquatic Resources Section, American Fisheries Society


Director, Salmonid Association of Eastern Newfoundland


COSEWIC Marine Fishes Specialist Subcommittee


Forrest Research Foundation International Visiting Fellow


Visiting Fellow, Institute of Advanced Studies, University of Western Australia


Board of Editors, Northeastern Naturalist


President, Canadian Conference for Fisheries Research


Dobbin Scholar, Ireland Canada University Foundation


Chair of the Board of Directors,

Protected Areas Association of Newfoundland & Labrador





January 2024

·      Recruitment of new trainees.

o   Recruitment continues for our upcoming salmon team. This work is in collaboration with Prof. Shawn Leroux, and a not-for-profit salmon focused group called ERMA.

o   Craig is recruiting a new student to work on brown trout charisma and how it relates to movement and spawning. See this link http://www.ucs.mun.ca/~cfpurchase/MScPosition-trout-CraigPurchase.pdf

o   It looks like Craig will be recruiting a new student to work on a special population of Acadian redfish. http://www.ucs.mun.ca/~cfpurchase/Postdoc_Position-MUN_redfish.pdf


December 2023

·      Craig, and Prof. Shawn Leroux have received some large grants that will enable several years of Atlantic salmon field work in the coming years. We have started recruiting a variety of trainees to take part in this work.

·      Three current and former MSc students have teamed up with Craig and have submitted a manuscript on the potential for brown trout hybridization.


November 2023

·      We had an intense month tagging spawning brown trout and conducting sperm competition experiments between brown trout and Atlantic salmon for Connor’s thesis.


September 2023

·      We are gearing up for salmonid spawning season. MSc student Connor Hanley is leading research on hybridization between native Atlantic salmon and invasive brown trout.

·      Welcome

o   to Katlyn Rowsell, who joins the lab as an undergraduate MUCEP student.

o   back to Nick Murphy, who has worked with us for the past two summers, and now joins us as an undergraduate research assistant.

·      Craig was recently in Sweden and Norway where he

o   attended the Biology of Spermatozoa conference

o   presented seminars

§  Evolutionary ecology of salmonid gametes: the potential influence of die ton hybridization, Sept 11 at the Institute of Freshwater Research of the Swedish University of Agricultural Sciences, in Stockholm Sweden.

§  Sperm biology & post-ejaculatory female mate choice in salmonid fishes, Sept 15 at University of Agder, in Kristiansand Norway.

o   sampled invasive brook trout and native brown trout with researchers from the University of Gothenburg.

o   met with researchers at the Kristineberg and Tjärnä field stations.




January 2023

·      Manuscript by former PhD student Marco Graziano was published in the Journal of Experimental Biology.

o   He was also featured in the early career spotlight

§  https://doi.org/10.1242/jeb.245427

Graziano, M., S. Palit, A. Yethiraj, S. Immler, M.J.G. Gage, & C.F. Purchase*. Frequency-dependent viscosity of salmon ovarian fluid has biophysical implications for sperm-egg interactions. Journal of Experimental Biology. https://doi.org/10.1242/jeb.244712



December 2022

·      Craig applied for three new grants from the Atlantic Salmon Conservation Foundation, and another from Fisheries & Oceans Canada, for future trainee opportunities.

·      Manuscript by former PhD student Heather Penney was accepted for publication in Ecology & Evolution.

o   Penney, H.D., D. Keefe, R. Perry, & C.F. Purchase*. Evidence of hatch time-based growth compensation in the early life history of two salmonid fishes. Accepted Ecology & Evolution. Pre-print DOI


October 2022

·      Craig presented some our work on hybridization at the Wild Trout Symposium

o   Purchase, C.F. 2022. The undiscovered contraception: does post-ejaculatory cryptic female choice reduce hybridization in salmonids? Wild Trout Symposium XIII. West Yellowstone, Montana, USA.

·      We began tagging brown trout in a nearby lake for future work on their life histories and reproduction.


May 2022

·      We have an opening for a new MSc or PhD student to work on sperm competition. Interested students should email Craig a CV, unofficial copy of transcripts, and a cover letter. Part of this cover letter should include elaboration on any previous work with behavioural ecology, sexual selection, sperm biology, fish biology, or genetics. See links under Opportunities for more details.

·      The summer 2022 capelin research team is in place. Welcome to Johanna Bosch, Maliya Cassels, Tatiana Hyde, Gage Moffatt, and Nick Murphy.

·      Kelly’s first paper has been submitted for peer-review and is available as a preprint. https://www.researchsquare.com/article/rs-1514165/v1



January 2022

·      Purchase, C.F., A.C. Rooke, M.J. Gaudry, J.R. Treberg, E.A. Mittell, M.B. Morrissey & M.D. Rennie. A synthesis of senescence predictions for indeterminate growth, and support from multiple tests in wild lake trout. Proceedings of the Royal Society B, 289.

o   https://doi.org/10.1098/rspb.2021.2146

·      Congratulations to Kelly MacDonald for the successful completion of her MSc thesis “Movers and shakers: exploring the complex dynamics of aquatic biological invasions”


December 2021

·      Tyler’s first paper has been submitted for peer-review and is available as a preprint “Lantiegne, T.H., & C.F. Purchase. Can cryptic female choice prevent invasive hybridization in external fertilizing fish?”

Preprint DOI


November 2021

·      Congratulations to Tyler whose MSc thesis has passed through examiners with flying colours. “Cryptic female choice and gamete-mediated paternal effects in the context of interspecific hybridization”

·      We are moved into the new science building, and are slowly becoming operational.


August 2021

·      We are ready to move into new $325 million science building, and are scheduled to begin August 16!

·      A long distance welcome to Ranjan Wagle, who is coming from Nepal to start a MSc with us in January 2022.


April 2021

·      Welcome to Jayme Bonnell, who is joining the team under a Science Undergraduate Research Award (SURA) for the summer.


September 2020

·      We are getting use to the pandemic, and the lab is emerging from the blue

·      Kelly has been in the field since July, electrofishing for juvenile salmonids

·      Paper on how temperature affects catch and release mortality in salmonid has been published in CJFAS, with Craig as co-author


January 2020

·      Paper by Craig and Anna on freezing ovarian fluid for cryptic female choice experiments was accepted by the Journal of Fish Biology.


December 2019

·      Paper by Orbach, Rooke, Evans, Pitcher and Purchase on “mate choice in capelin” was accepted for publication by the Journal of Evolutionary Biology.


November 2019

·      Paper lead by Dara on “capelin sexual dimorphism” was published in the Journal of Fish Biology.

·      Craig gave two research talks at the University of Western Australia


October 2019

·      Paper led by Heather on “reproductive constraints in killifish” was published

·      Kelly and Madison presented their research at the annual Salmonid Council of Newfoundland & Labrador meeting

·      Craig arrived in Perth Australia where he is spending part of his sabbatical at UWA


September 2019

·      Craig has been elected as the Vice-President (2020-2021) and President (2022-2023) of the Canadian Aquatic Resources Section, of the American Fisheries Society


August 2019

·      Congrats to Steven Poulos for having his MSc thesis pass examination

·      Craig presented the lake trout senescence project at the Biology of Sperm meeting in Sweden


April 2019

·      2nd paper from our oil spill research has been published by the journal Marine Environmental Research. Titled “Impact of crude oil and dispersant on capelin embryo development” it stems from research funded by the National Contaminants Advisory Group of Fisheries and Oceans Canada. https://www.sciencedirect.com/science/article/pii/S0141113618307050

o   The 1st paper from this project was published in the fall in the journal Environmental Pollution, and is titled “Chemically-dispersed crude oil and dispersant affects sperm fertilizing ability, but not sperm swimming behaviour in capelin”. https://www.sciencedirect.com/science/article/pii/S0269749118301714

·      Paper titled “The impact of a changing winter climate on the hatch phenology of one of North America’s largest Atlantic salmon populations” has been accepted for publication by Conservation Physiology.

·      Paper titled “Fish sperm competition in hatcheries and between wild and hatchery origin fish in nature” has been accepted for publication in  Theriogenology.


March 2019

·      Craig was an invited expert on 3 DFO meetings this month: Regional Science Advisory Processes for Atlantic salmon and capelin, and Recovery Action Plan for lumpfish.

·      Craig gave an invited talk at an upcoming WWF Salmon Habitat Restoration Workshop on March 28, called “Global synthesis of the effectiveness of various salmonid spawning habitat enhancements and key recommendations for Newfoundland salmon”


February 2019

·      Congratulations to Heather Penney, who successfully defended her PhD thesis on Feb 1.


January 2019

·      Craig and Anna, along with Mike Rennie (Lakehead U) and Jay Treberg (U Manitoba) presented work on lake trout reproduction at the Canadian Conference for Fisheries Research in London Ontario.  “Old funks don’t always have junk spunk: a clear lack of reproductive senescence in  sperm quality within the long-lived indeterminate growing lake trout”


October 2018

·      We had a team of 6 at the ERMA facilities on the Grandfalls fishway, where we sampled 70 salmon for Madison’s project on among-individual variation in sperm quality.

·      We were thrilled to be hosting Geoff Parker (retired University of Liverpool) who received an Honorary Doctor of Science from MUN on October 18.

·      Craig was interviewed October 10 about “Cressie” for an upcoming episode of the TV show “Rare Earth Uncovered” on APTN.

·      Welcome to Taylor Hughes and Coady Fitzpatrick who join the lab as MUCEP students, and Terry Sullivan who is back with us for the 3rd fall of salmon spawning.


August 2018

·      Craig spent 7 days in a remote site of Prince William Sound Alaska, working with Peter Westley (UAF) on pink salmon reproduction