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Stacy A. Krueger-Hadfield headshot.

Associate Professor This email address is being protected from spambots. You need JavaScript enabled to view it.
3123 East Science Hall, Science & Engineering Complex
(205) 934-6034
Lab website

Research and Teaching Interests: Evolutionary Ecology, Population Genetics, Phycology, Scientific Communication

Office Hours: By appointment


  • B.S., California State University Northridge, Environmental Biology
  • M.S., California State University Northridge, Marine Biology
  • Ph.D., Pontificia Universidad Católica de Chile, Marine Ecology
  • Ph.D., Université de Pierre et Marie Curie Sorbonne Universités, Molecular Ecology/Phycology

I grew up in the San Fernando Valley in southern California. Regular trips to the seaside and tide pools along the central coast and Monterey Bay engendered a lifelong interest in marine biology. I obtained my B.S. and M.S. from California State University Northridge. I then embarked on my dissertation research at the Station Biologique de Roscoff and the Pontificia Universidad Católica de Chile. I earned a Ph.D. from each institution and had the opportunity to live and work in France and Chile. My postdoctoral work at the Marine Biological Association and at the Grice Marine Laboratory took me back to Chile, and to South Africa, Japan, and throughout North America and Europe sampling tunicates and algae.

Research Opportunities
If you are interested in joining the Krueger-Hadfield Evolutionary Ecology Lab, please send your CV and a short research proposal to This email address is being protected from spambots. You need JavaScript enabled to view it.. The research proposal should highlight your research interests and how you see those interests intersecting with our research themes.

In 2014, I became a regular contributor to the blog The Molecular Ecologist (TME) in which I write weekly shorts (and sometimes longer posts — see this post on my journey to becoming a marine biologist) on the latest in molecular ecology. In 2016, I joined the faculty at UAB and was able to develop a science communication course for graduate students. This has also recently included chairing the Darwin Day events (2018-present). My science communication work was recognized by the Ecological Society of America #MySciComm and my lab was recently highlighted by the Society for the Study of Evolution New Faculty Profile. I serve on the communications committee for the Phycological Society of America and also serve as an Associate Editor for the Journal of Phycology, Cryptogamie Algologie, and Marine Biodiversity Records. In 2020, I became the editor of social media at the American Genetics Association and am the editor of the AGA blog.

  • Research Interests

    We use molecular biology, ecological theory, evolutionary theory, and natural history to explore marine and freshwater ecosystems. We typically use algal and invertebrate models to ask questions about the evolution of sex, mating systems, and life cycles. Check out the research conducted by Dr. Krueger-Hadfield and her lab on her website.

  • Recent Courses
    • BY245/BY555: Principles of Scientific Investigation
    • BY 429/BY 491/BY 629: Introduction to Evolutionary Processes
    • BY 468/BY 668: Conservation Genetics
    • BY 655/BY 755: Biometry
    • BY 670/BY 770: Science Communication
  • Select Publications
    • Flanagan BA, SA Krueger-Hadfield, CJ Murren, CC Nice, AE Strand, EE Sotka(2021) Founder effects shape linkage disequilibrium and genomic diversity of a partially clonal invader. Molecular Ecology https://onlinelibrary.wiley.com/doi/10.1111/mec.15854
    • Bonthond G, T Bayer, SA Krueger-Hadfield, N Stärk, G Wang, M Nakaoka, S Künzel, F Weinberger (2021) Increased host promiscuity may have promoted invasiveness of a macroalgal holobiont. ISME https://www.nature.com/articles/s41396-020-00878-7
    • Cahill R, SA Krueger-Hadfield, WH Ryan (2021) The effects of stress on the bacterial community associated with the sea anemone Diadumene lineata. Journal of Emerging Investigators 3: 1-7.
    • Ryan WH, J Aida, SA Krueger-Hadfield (2021) The contribution of clonality to population genetic structure in the sea anemone Diadumene lineata. Journal of Heredity https://academic.oup.com/jhered/advance-article/doi/10.1093/jhered/esaa050/6122458
    • Krueger-Hadfield SA, C Destombe, ML Guillemin, M Valero, S Stoeckel (2021) Exploring the genetic consequences of clonality in haplodiplontic taxa. Journal of Heredity esaa063 https://academic.oup.com/jhered/advance-article/doi/10.1093/jhered/esaa063/6123561
    • Stoeckel S, S Arnaud-Haond, SA Krueger-Hadfield (2021) The combined effect of haplodiplonty and partial clonality in population genetics. Journal of Heredity esaa062
    • Orive ME, SA Krueger-Hadfield (2021) Sex and asex: a clonal lexicon. Journal of Heredity esaa058 https://academic.oup.com/jhered/advance-article/doi/10.1093/jhered/esaa058/6041422
    • Schoenrock KM, T McHugh, SA Krueger-Hadfield (2021) Revisiting the ‘bank of microscopic forms’ in macroalgal-dominated ecosystems. Journal of Phycology 57: 14-29.
    • Krueger-Hadfield SA, BA Flanagan, O Godfroy, KM Hill-Spanik, CC Nice, CJ Murren, AE Strand, EE Sotka (2021) Using RAD-seq to develop sex-linked markers in a haplodiplontic alga. Journal of Phycology 57: 279-294.
    • McCoy SJ, SA Krueger-Hadfield, N Mieszkowska (2020) Towards a macroalgal species conceptual framework. Journal of Phycology 56: 1404-1413
    • Krueger-Hadfield SA, WH Ryan (2020) Influence of nutrients on ploidy-specific performance in a haplodiplontic red macroalga. Journal of Phycology 56: 1114-1120
    • Schoenrock KM, KM Chan, T O’Callaghan, R O’Callaghan, A Golden, SA Krueger-Hadfield, AM Power (2020) A review of subtotal kelp forests in Ireland: from first descriptions to new habitat monitoring techniques. Ecology and Evolution 10:6819-6832
    • Lipinska A, J Collén, SA Krueger-Hadfield, T Mora, E Ficko-Blean (2020) To gel or not gel: Differential gene expression of carrageenan-related genes between the gametophyte and tetrasporophyte life cycle stages of the red alga Chondrus crispus. Scientific Reports 10:11498
    • Bonthond G, T Bayer, SA Krueger-Hadfield, FR Barboza, M Nakaoka, M Valero, G Wang, S Künzel, and F Weinberger (2020) Variation across ecological scales in microbial communities associated with an invasive seaweed. Molecular Ecology 29:2094-2108
    • Schoenrock KM, A O’ Connor, S Mauger, J Neiva, E Serrão, M Valero, SA Krueger-Hadfield (2020) Genetic diversity of a marine foundation species, Laminaria hyperborea (Gunnerus) Foslie, along the coast of Ireland. European Journal of Phycology 55:310-326
    • Olsen KC, WH Ryan, AA Winn, ET Kosman, Moscoso JA, SA Krueger-Hadfield, SC Burgess, DB Carlon, RK Grosberg, S Kalisz, DR Levitan (2020) Inbreeding shapes the evolution of marine invertebrates. Evolution 74: 871-882
    • Krueger-Hadfield SA (2020) What’s ploidy got to do with it? Understanding the evolutionary ecology of macroalgal invasions necessitates incorporating life cycle complexity. Evolutionary Applications 13: 486-499.
    • Krueger-Hadfield SA, AMH Blakeslee, AE Fowler (2019) Incorporating ploidy diversity into ecological and community genetics. Journal of Phycology 55: 1198-1207.
    • Ryan WH, L Adams, G Bonthond, N Mieszkowska, KE Pack, SA Krueger-Hadfield (2019) Environmental regulation of individual body size contributes to geographic variation in clonal life cycle expression. Marine Biology 166:157.
    • Ryan WH, S Heiser, MD Curtis, CD Amsler, T Bayer, G Bonthond, G Wang, F Weinberger, SA Krueger-Hadfield (2019) The use of photographic color information for high-throughput phenotypic of pigment concentration in Agarophyton vermiculophyllum. Cryptogamie Algologie 40: 73-83.
    • Marin-Felix Y, M Hernández-Restrepo I Iturrieta-González, D García, J Gené, JZ Groenewald, L Cai, Q Chen, W Quaedvlieg, RK Schumacher, PWJ Taylor, C Ambers, G Bonthond, J Edwards, SA Krueger-Hadfield, JJ Luangsaard, L Morton, A Moslemi, M Sandoval-Denis, YP Tan, R Thangavel, N Vaghefi, R Cheewangkoon, PW Crous (2019) Genera of phytopathogenic fungi: GOPHY 3. Studies in Mycology 94: 1-124.
    • Schoenrock KM, T O’Callaghan, R O’Callaghan, SA Krueger-Hadfield (2019) First record of Laminaria ochroleuca Bachelot de la Pylaie in Ireland in Béal an Mhuirthead, County Mayo. Marine Biodiversity Records 12:9.
  • Academic Distinctions and Professional Societies

    Professional societies:

    • British Phycological Society
    • Phycological Society of America
    • Society for the Study of Evolution

    Academic Distinctions: