Carolyn Faithfull

I am an aquatic ecologist whose specialty is in studying food web interactions in pelagic ecosystems. Much of my research focusses on how multiple stressors affect energy transfer in food webs. I have also worked with surveying Gävleborgs marine environment in order to prioritise areas for building of marine protected areas. I have wide interests in the aquatic environment, and have investigated methods to restore charophyte meadows and am working in a interdisciplinary group to develop new frameworks in incorporate social aspects into restoration activities.

I lecture on the state of the Baltic Sea in the course Land and watershed management (MV0217) and we discuss strategies to reduce eutrophication. In the course Environmental Analysis (MX0159) I present methods for environmental monitoring in the Baltic Sea and we discuss how monitoring data can be used for management purposes. In 2023 I was involved in developing the PhD course “Source to Sea” and held a module called “Introduction to large-scale risk assessment and engaging stakeholders in the process.” 

Project coordinator of MSP4MORE

Chair of ICES working group for Integrated Assessments of the Baltic Sea (WGIAB)

Member of HELCOM Food webs expert group

Scientist supporting Ecosystem based marine management of the Southian Bothnian Sea.  

2020 - Researcher, Institute of Coastal research, SLU

2017-2020 - Marine Biologist, County Board Gävleborg

2014-2018 - International Postdoctor, Oceanography Institution, University of Hawai’i and Umeå University.

2012-2014 - Researcher/Postdoctor, Umeå University

2011 - PhD, Umeå University

2022-present Co-supervisor PhD student Benjamin Mooney

2025 Supervisor Master thesis Dilara Cicek

2015-2016 Supervisor Master thesis Lauren Mathews

2016-2019 Co-supervisor PhD student Annie Deiningar

Mooney BP., Gårdmark A., Faithfull CL., van Dorst RM, Huss M. (2025). Warmer lakes support phytoplankton over fish. Global Change Biology. 31: e70288. 

CL Faithfull and L Bergström. (2025) Temporal changes in the Bothnian Sea food web reveal a deterioration linked to fishing pressure and recent eutrophication. ICES Journal of Marine Science. 10.1093/icesjms/fsaf025. 

ICES. 2025. Workshop on the operational use of Food Web indicators and information (WKFoodWeb; outputs from 2024 meeting). ICES Scientific Reports. 7:49. 59 pp. 

CL Faithfull, E Tamarit, P Nordling, E Kraft (2024). Restoring charophytes is still a challenge: A call for developing successful methods. Aquatic Botany 193, 103777. 

ICES. 2024. Baltic Sea ecoregion – Ecosystem overview. In Report of the ICES Advisory Committee, 2024. ICES Advice 2024, Section 7.1.

ICES. 2024. Workshop for the revision of Ecosystem Overviews of the Baltic Sea Ecoregion (WKBALEO). ICES Scientific Reports. 6:91. 71 pp. 

C.L. Faithfull, S.A. Wikström, and L. Bergström (2024). Conceptual Models as Support for Ecosystem-Based Management: Case Studies from the Southern Bothnian Sea and Stockholm Archipelago Pilot Areas. Swedish Agency for Marine and Water Management Report 2024:14. 

S.A. Wikström, L. Bergström, P. Thor, C. Faithfull, M. Erlandsson, B. Dessirier, U. Bergström … (2024). Ecosystem Service Analyses as Support for Regional Ecosystem-Based Marine Management. Swedish Agency for Marine and Water Management Report 2024:05. 

C. Solér, R. Bankel, C. Faithfull (2024). Economic, Social, and Ecological Sustainability in the Southern Bothnian Sea. Swedish Agency for Marine and Water Management Report 2024:02. 

C. Faithfull, B. Koehler, U. Bergström, C. Berkström, M. Erlandsson, ... (2021). Knowledge Base for Ecosystem-Based Marine Management in the Bothnian Sea. Aqua Reports 2021:13. 

C.L. Faithfull, P. Nordling, E. Kraft, C. Nyberg (2020). Recreational Fishing Survey in Gävleborg 2019. County Administrative Board of Gävleborg Report 2020:13. 

Faithfull C.L., and Goetze E. Copepod nauplii use phosphorus from bacteria, creating a short circuit in the microbial loop. Ecology Letters, 22: 1462-1471.

Mathews L., Faithfull C.L., Lenz, P.H., Nelson C. The effects of food stoichiometry and temperature on copepods are mediated by ontogeny. Oecologia, 188: 75-84.

Mehdi Cherif, Carolyn Faithfull, Junwen Guo, Cedric L. Meunier, Judith Sitters,
Wojciech Uszko, Francisco Rivera Vasconcelos. (2017). An Operational Framework for
the Advancement of a Molecule-to-Biosphere Stoichiometry Theory. Frontiers in
Marine Science, 4: 268.

Deininger A. Faithfull C.L., Bergström A.-K. (2017). Nitrogen effects on the pelagic
food web are modified by dissolved organic carbon. Oecologia, 4:901-916.

Deininger A. Faithfull C.L., Bergström A.-K. (2017). Phytoplankton response to whole lake inorganic N fertilization along a gradient in dissolved organic carbon. Ecology, 98:982-994.

Deininger A., Faithfull C.L., Karlsson J., Klaus M., and Bergström A.K. (2017).
Pelagic food web response to whole lake N fertilization. Limnology and Oceanography, 62:1498-1511.

Deininger A., Faithfull C. L., Lange K., Bayer T., Vidussi F. and Liess A. (2016).
Phytoplankton succession and stoichiometry changes triggered by terrestrial runoff in a coastal lagoon. Marine Environmental Research, 119: 40-50.

Liess A., Rowe O., Francoeur S.N., Guo J., Lange K., Schröder A., Reichstein B.,
Lefebure R., Deininger A., Mathisen P., Faithfull C.L. (2016). Terrestrial runoff boosts
phytoplankton in a Mediterranean coastal lagoon, but these effects do not propagate to higher trophic levels. Hydrobiologia, 766: 275-291.

Faithfull C.L., Mathisen P., Wenzel A., Bergström A.K. and Vrede T. (2015). Food web efficiency differs between humic and clear water lake communities in response to nutrients and light. Oecologia, 177:823-835.

Liess A., Faithfull C.L. Reichstein B., Rowe O., Guo J., Pete R., Thomsson G., Uszko
W. and Francoeur S.N. (2015). Terrestrial runoff may reduce microbenthic net
community productivity by increasing turbidity: A Mediterranean coastal lagoon
mesocosm experiment. Hydrobiologia, 753:215-218.

Bergström A.K., Faithfull C.L., Karlsson D., Karlsson J. (2013). Nitrogen deposition
and warming – Effects on phytoplankton nutrient limitation in subarctic lakes. Global Change Biology, 19: 2557-2568.

Faithfull C.L, Huss M., Vrede T., Karlsson J. and Bergström A.-K. (2012). Transfer of bacterial production based on labile carbon to higher trophic levels in an oligotrophic pelagic system. Canadian Journal of Fisheries and Aquatic Sciences, 69: 85-93.

Faithfull C.L., A. Wenzel, T. Vrede, A.-K. Bergström (2011). Testing the light:nutrient hypothesis in an oligotrophic boreal lake. Ecosphere, 2: art UNSP123

Faithfull C.L., A.-K. Bergström and T. Vrede (2011). Effects of nutrients and lake
characteristics on bacterial and phytoplankton production: A meta-analysis. Limnology and Oceanography, 56: 1708–1713.

Faithfull C.L., Huss M., T. Vrede and A.-K. Bergström (2011). Bottom-up carbon
subsidies and top-down predation pressure interact to affect aquatic food web structure. Oikos, 120: 311–320.

Faithfull C.L., A.-K. Bergström and T. Vrede (2009). Pelagic energy mobilization
across crossed gradients of phosphorus and dissolved organic carbon in a chemostat
experiment. Internat. Assoc. of Theoretical and Applied Limnology, 30: 1411–1415.

Faithfull C.L. and C.W. Burns (2006). Effects of salinity and source of inocula on
germination of Anabaena akinetes from a tidally-influenced lake. Freshwater Biology, 51: 705–716.