Mehis Rohtla

Postdoctoral Research Scientist

Institute of Marine Research
Ecosystems Acoustics Group
Austevoll Research Station
5392 Storebø, NORWAY

Email: mehis.rohtla@hi.no

Education

PhD (2015) in Ichthyology and Fisheries, University of Tartu
MSc (2010) in Zoology and Hydrobiology, University of Tartu
BSc (2008) in Biology, University of Tartu

Areas of expertise and interest

My main professional interest has been in fish migration and recruitment. More specifically I have been interested in fish migration patterns within/between fresh and brackish water, age at first migration and at maturation, and also in natal origins (i.e., fresh or brackish water, natal river).

I have worked with several diadromous and fresh and brackish water resident species mostly in the Baltic Sea region, but also elsewhere. Since my masters studies, the main focus has been on using different otolith microchemistry methods to tackle the aforementioned problems in order to provide novel scientific input for various stock management and conservation actions. More recently I have also become involved with different PIT and acoustic telemetry methods.

I also gladly collaborate with people from other fields (e.g., fish geneticists and physiologists) in order to take on a holistic approach for fishy questions with complex nature.

Active projects

  • The importance of the marine habitat for the critically endangered European eel (Led by Caroline Durif)

Publications

Blood-based gene expression as non-lethal tool for inferring salinity-habitat history of European eel (Anguilla anguilla)

Bertolini, F., M. Rohtla, C. Parzanini, J. Tomkiewicz & C.M.F. Durif. 2022. Blood-based gene expression as non-lethal tool for inferring salinity-habitat history of European eel (Anguilla anguilla). Scientific Reports 12, 22142. doi: 10.1038/s41598-022-26302-y.
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Transcriptomic tool to determine European eel marine residency for use in monitoring and management (2TEM)

Durif, C., F. Bertolini, A. Zaratiegui Pedrosa, M. Rohtla, J. Tomkiewicz. 2022. Transcriptomic tool to determine European eel marine residency for use in monitoring and management (2TEM). Nordic Council of Ministers. doi: 10.6027/temanord2022-550.
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Read a story about the work (in Norwegian)

Habitat use and growth of yellow-stage European eel in coastal and freshwater ecosystems in Norway

Rohtla, M., F. Daverat, M.T. Arts, H.I. Browman, C. Parzanini, A.B. Skiftesvik, E.B. Thorstad, T. van der Meeren, L.A. Vøllestad & C.M.F. Durif. 2022. Habitat use and growth of yellow-stage European eel in coastal and freshwater ecosystems in Norway. Canadian Journal of Fisheries and Aquatic Sciences. doi: 10.1139/cjfas-2022-0033.
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Overwintering behaviour of yellow-stage European eel (Anguilla anguilla) in a natural marine fjord system

Rohtla, M., E. Moland, A.B. Skiftesvik, E.B. Thorstad, S. Bosgraaf, E.M. Olsen, H.I. Browman & C.M.F. Durif. 2022. Overwintering behaviour of yellow-stage European eel (Anguilla anguilla) in a natural marine fjord system. Estuarine, Coastal and Shelf Science. doi: 10.1016/j.ecss.2022.108016.
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Trophic position of the European eel (Anguilla anguilla) across different salinity habitats inferred from fatty acid and stable isotope analysis

Parzanini, C, M.T. Arts, M. Power, M. Rohtla, A.B. Skiftesvik, J. Koprivnikar, H.I. Browman, D. Milotic, C.M.F. Durif. 2021. Trophic position of the European eel (Anguilla anguilla) across different salinity habitats inferred from fatty acid and stable isotope analysis. Canadian Journal of Fisheries and Aquatic Science 78: 1721-1731. Doi: 10.1139/cjfas-2020-0432.
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Feeding habitat and silvering stage affect lipid content and fatty acid composition of European eel (Anguilla anguilla) tissues

Parzanini, C, M.T. Arts, M. Rohtla, J. Koprivnikar, M. Power, A.B. Skiftesvik, H.I. Browman, D. Milotic, C.M.F. Durif. 2021. Feeding habitat and silvering affect lipid content and fatty acid composition of European eel (Anguilla anguilla) tissues. Journal of Fish Biology 99: 1110-1124. doi: 10.1111/jfb.14815.
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Variability in stream water chemistry and brown trout (Salmo trutta L.) parr otolith microchemistry on different spatial scales

Matetski, L., Rohtla, M., Svirgsden, R., Kesler, M., Saks, L., Taal, I., Hommik, K., Paiste, P., Kielman-Schmitt, M., Kooijman, E., Birzaks, J., Saura, A., Ziņģis, M., Vaittinen, M., & Vetemaa, M. 2021. Variability in stream water chemistry and brown trout (Salmo trutta L.) parr otolith microchemistry on different spatial scales. Ecology of Freshwater Fish, 00, 1–16. doi: 10.1111/eff.12642.
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Review and meta-analysis of the environmental biology and potential invasiveness of a poorly-studied cyprinid, the Ide Leuciscus idus

Rohtla, M., L. Vilizzi, V. Kováč, D. Almeida, B. Brewster, J.R. Britton, Ł. Głowacki, M.J. Godard, R. Kirk, S. Nienhuis, K.H. Olsson, J. Simonsen, M.E. Skóra, S. Stakėnas, A.S. Tarkan, N. Top, H. Verreycken, G. Zięba & G.H. Copp. 2020. Review and meta-analysis of the environmental biology and potential invasiveness of a poorly-studied cyprinid, the Ide Leuciscus idus. Reviews in Fisheries Science & Aquaculture, doi: 10.1080/23308249.2020.1822280.
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Conservation restocking of the imperilled European eel does not necessarily equal conservation

Rohtla, M., M. Slim, J. Tulonen, P. Paiste, H. Wickström, M. Schmitt, E. Kooijman, V. Vaino, R. Eschbaum, L. Saks, A. Verliin, & M. Vetemaa. 2021. Conservation restocking of the imperilled European eel does not necessarily equal conservation. ICES Journal of Marine Science, doi: 10.1093/icesjms/fsaa196.
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Quantifying an overlooked aspect of partial migration using otolith microchemistry

Rohtla, M., L. Matetski, I. Taal, R. Svirgsden, M. Kesler, P. Paiste & M. Vetemaa. 2020. Quantifying an overlooked aspect of partial migration using otolith microchemistry. Journal of Fish Biology 2020; 1-4. DOI: 10.1111/jfb.14522.
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Essential coastal habitats for fish in the Baltic Sea

Kraufvelin, P., Pekcan-Hekim, Z., Bergström, U., Florin, A.B., Lehikoinen, A., Mattila, J., Arula, T., Briekmane, L., Brown, E.J., Celmer, Z., Dainys, J., Jokinen, H., Kääriä, P., Kallasvuo, M., Lappalainen, A., Lozys, L., Möller, P., Orio, A., Rohtla, M., Saks, L., Snickars, M., Støttrup, J., Sundblad, G., Taal, I., Ustups, D., Verliin, A., Vetemaa, M., Winkler, H., Wozniczka, A. & Olsson, J. 2018. Essential coastal habitats for fish in the Baltic Sea. Estuarine, Coastal and Shelf Science 204, 14−30.
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Evidence of Atlantic salmon Salmo salar fry movement between fresh water and a brackish environment

Taal, I., Rohtla, M., Saks, L., Svirgsden, R., Kesler, M., Matetski, L. & Vetemaa, M. 2017. Evidence of Atlantic salmon Salmo salar fry movement between fresh water and a brackish environment. Journal of Fish Biology 91, 695-703.
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Quantitative X-ray fluorescence computed tomography for low-Z samples using an iterative absorption correction algorithm

Huang, R., Limburg, K.E. & Rohtla, M. 2017. Quantitative X-ray fluorescence computed tomography for low-Z samples using an iterative absorption correction algorithm. AIP Advances 7, 0551.
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Do sea trout Salmo trutta parr surveys monitor the densities of anadromous or resident maternal origin parr, or both?

Rohtla, M., Matetski, L., Svirgsden, R., Kesler, M., Taal, I., Saura, A., Vaittinen, M. & Vetemaa, M. 2017. Do sea trout Salmo trutta parr surveys monitor the densities of anadromous or resident maternal origin parr, or both? Fisheries Management and Ecology 24, 156−162.
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Parr dispersal between streams via a marine environment: A novel mechanism behind straying for anadromous brown trout?

Taal, I., Rohtla, M., Saks, L., Kesler, M., Jürgens, K., Svirgsden, R., Matetski, L., Paiste, P., Verliin, A. & Vetemaa, M. 2018. Parr dispersal between streams via a marine environment: A novel mechanism behind straying for anadromous brown trout? Ecology of Freshwater Fish 27, 209−215.
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Diel changes in brackish non-tidal surf zone fish assemblage in the Eastern Baltic coast

Taal, I., Saks, L., Rohtla, M., Jürgens, K., Svirgsden, R., Kesler, M., Verliin, A., Hubel, K., Albert, A., Eschbaum, R., Saat, T. & Vetemaa, M. 2017. Diel changes in brackish non-tidal surf zone fish assemblage in the Eastern Baltic coast. Boreal Environment Research 22, 83−96.
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Developing novel means for unravelling the population structure, provenance and migration patterns of European whitefish Coregonus lavaretus s.l. in the Baltic Sea

Rohtla, M., Svirgsden, R., Verliin, A., Rumvolt, K., Matetski, L., Hommik, K., Saks, L. & Vetemaa, M. 2017. Developing novel means for unravelling the population structure, provenance and migration patterns of European whitefish Coregonus lavaretus s.l. in the Baltic Sea. Fisheries Research 187, 47−57.
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Otolith chemistry chimes in: migratory environmental histories of Atlantic tarpon (Megalops atlanticus) caught from offshore waters of French Guiana

Rohtla, M. & Vetemaa, M. 2016. Otolith chemistry chimes in: migratory environmental histories of Atlantic tarpon (Megalops atlanticus) caught from offshore waters of French Guiana. Enviromental Biology of Fishes 99, 593–602.
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Invasion of round goby to the small watercourses in Estonian coast, Baltic Sea

Verliin, A., Kesler, M., Svirgsden, R., Taal, I., Saks, L., Rohtla, M., Hubel, K., Eschbaum, R., Vetemaa, M. & Saat, T. 2017. Invasion of round goby to the small watercourses in Estonian coast, Baltic Sea. Ichthyological Research 64, 155−158.
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Variations in egg characteristics of ruffe Gymnocephalus cernua inhabiting brackish and freshwater environments

Svirgsden, R., Albert, A., Rohtla, M., Taal, I., Saks, L., Verliin, A., Kesler, M., Hubel, K., Vetemaa, M. & Saat, T. 2015. Variations in egg characteristics of ruffe Gymnocephalus cernua inhabiting brackish and freshwater environments. Helgoland Marine Research 69, 273−283.
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Life history characteristics of ide Leuciscus idus in the Eastern Baltic Sea

Rohtla, M., Svirgsden, R., Taal, I., Saks, L., Eschbaum, R. & Vetemaa, M. 2015. Life history characteristics of ide Leuciscus idus in the Eastern Baltic Sea. Fisheries Management and Ecology 22, 239–248.
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Old timers from the Baltic Sea: revisiting the population structure and maximum recorded age of ide Leuciscus idus

Rohtla, M., Taal, I., Svirgsden, R. & Vetemaa, M. 2015. Old timers from the Baltic Sea: revisiting the population structure and maximum recorded age of ide Leuciscus idus. Fisheries Research 165, 74–78.
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Evidence for an autumn downstream migration of Atlantic salmon Salmo salar (Linnaeus) and brown trout Salmo trutta (Linnaeus) parr to the Baltic Sea

Taal, I., Kesler, M., Saks, L., Rohtla, M., Verliin, A., Svirgsden, R., Jürgens, K., Vetemaa, M. Saat, T. 2014. Evidence for an autumn downstream migration of Atlantic salmon Salmo salar (Linnaeus) and brown trout Salmo trutta (Linnaeus) parr to the Baltic Sea. Helgoland Marine Research 68, 373–377.
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Using otolith 87Sr: 86Sr as a natal chemical tag in the progeny of anadromous Baltic Sea pike (Esox lucius) – a pilot study

Rohtla, M., Vetemaa, M., Svirgsden, R., Taal, I., Saks, L., Kesler, M., Verliin, A. & Saat, T. 2014. Using otolith 87Sr: 86Sr as a natal chemical tag in the progeny of anadromous Baltic Sea pike (Esox lucius) – a pilot study. Boreal Environment Research 19, 379– 386.
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Whitefish (Coregonus lavaretus (L.)) landings in the Baltic Sea during the past 100 years: combining official datasets and grey literature

Verliin, A., Saks, L., Svirgsden, R., Vetemaa, M., Rohtla, M., Taal, I. & Saat, T. 2013. Whitefish (Coregonus lavaretus (L.)) landings in the Baltic Sea during the past 100 years: combining official datasets and grey literature. Advances in Limnology 64, 133–152.
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Life history of anadromous burbot (Lota lota, Linneaus) in the brackish Baltic Sea inferred from otolith microchemistry

Rohtla, M., Vetemaa, M., Taal, I., Svirgsden, R., Urtson, K., Saks, L., Verliin, A., Kesler, M. & Saat, T. 2014. Life history of anadromous burbot (Lota lota, Linneaus) in the brackish Baltic Sea inferred from otolith microchemistry. Ecology of Freshwater Fish 23, 141–148.
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Early life migration patterns of Baltic Sea pike Esox lucius

Rohtla, M., Vetemaa, M., Urtson, K. & Soesoo, A. 2012. Early life migration patterns of Baltic Sea pike Esox lucius. Journal of Fish Biology 80, 886–893.
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Last updated: November 1, 2022