Life history traits and timing of elvers moving over a River Meuse dam after recent glass eel restocking

Abundance; Catch periodicity; Fish species assemblage; Glass eels; Growth rate; Large deep riverine ecosystems; Restocking; Ecology, Evolution, Behavior and Systematics; Ecology; Aquatic Science; Animal Science and Zoology

Abstract :

[en] This study describes for the first time some aspects of the life history traits and movement behaviour of young eels during the first year following their capture on the French Atlantic coasts that were released as glass eels into a large river with a vast catchment area. The restocked individuals have small size, exhibit discrete, cryptic, and benthic life habits, and have nocturnal activity. These make capturing individuals and studying this stage very challenging. Taking advantage of its positive thigmotactic behaviour, we used a fishway adapted for eels to collect samples using eel traps and trap pools lined with freshwater mussel shells. Results revealed that the restocked eels’ abundance has positively impacted the eel local stock, growth rate was good, catch periodicity followed that of older eel individuals, and composition of the associated fish species was indicative of the fish fauna that ascends the River Meuse through this fishway. These findings would open prospects for restocking using glass eels as a viable strategy to boost declining local stocks and, probably in the long term, increase the future escapement rate to the sea of silver eel spawners from the catchment, but the question of survival in large rivers still needs more research.

Research Center/Unit :

FOCUS - Freshwater and OCeanic science Unit of reSearch - ULiège
AFFISH-RC - Applied and Fundamental FISH Research Center - ULiège

Disciplines :

Environmental sciences & ecology

Author, co-author :

Matondo, Billy Nzau ; Laboratory of Fish Demography and Hydroecology, Management of Aquatic Resources and Aquaculture Unit, Freshwater and Oceanic science Unit of Research-FOCUS, University of Liège, Liège, Belgium

Ovidio, Michaël ; Université de Liège - ULiège > Freshwater and OCeanic science Unit of reSearch (FOCUS)

Language :

English

Title :

Life history traits and timing of elvers moving over a River Meuse dam after recent glass eel restocking

Publication date :

August 2026

Journal title :

Regional Studies in Marine Science

eISSN :

2352-4855

Publisher :

Elsevier B.V.

Volume :

101

Pages :

105285

Peer reviewed :

Peer reviewed

Additional URL :

https://api.elsevier.com/content/article/PII:S2352485526005402?httpAccept=text/xml

Funders :

EMFF - European Maritime and Fisheries Fund

Funding text :

This research was supported by the European Maritime Affairs and Fisheries Fund and the Wallonia Public Service Grant Project # A161\u20132311\u2013006 represented by Rachel Sundar Raj, Micka\u00EBl Dubois and Beno\u00EEt Thirionet. We would like to thank the Editor-in-chief, the Associate Editor Dr. Alberto Teodorico Correia and the two anonymous reviewers for their valuable comments on the manuscript, and the Walloon Public Service for Agriculture, Natural Resources and Environment in the Environment and Water Department of the Surface Water Directorate for providing the temperature and flow data.

Available on ORBi :

since 30 July 2026

Statistics

Number of views

55 (5 by ULiège)

Number of downloads

25 (0 by ULiège)

More statistics

Scopus citations^®

Scopus citations^®
without self-citations

OpenAlex citations

Bibliography

Aprahamian, M.W., 2000. The growth rate of eel in tributaries of the lower River Severn, England, and its relationship with stock size. J. Fish Biol. 56, 223–227. https://doi.org/10.1111/j.1095-8649.2000.tb02100.x.
Baras, E., Jeandrain, D., Serouge, B., Philippart, J.C., 1998. Seasonal variations in time and space utilization by radio-tagged yellow eels Anguilla anguilla (L.) in a small stream. Hydrobiologia 371(372),187–198. https://doi.org/10.1023/A:1017072213791.
Baras, E., Philippart, J.C., Salmon, B., 1996. Estimation of migrant yellow eels stock in large rivers through the survey of fish passes: A preliminary investigation in the River Meuse (Belgium). In Stock Assessment in Inland Fisheries, Cowx, I.G., Ed., Oxford Fishing News Books (Blackwell): London, UK, pp. 314–325. https://hdl.handle.net/2268/241195.
Belpaire, C., Breine, J., Wichelen, J.V., Nzau Matondo, B., Ovidio, M., Verhelst, P., Teunen, L., Bervoets, L., Dumonceau, F., Vlietinck, K., 2021. Report on the eel stock, fishery and other impacts in Belgium, 2020–2021. In Joint EIFAAC/ICES/GFCM Working Group on Eels (WGEEL), and Country Reports 2020–2021; ICES Scientific Reports; ICES: Copenhagen, Denmark, 2021.
Belpaire, C.G.J., Goemans, G., Geeraerts, C., Quataert, P., Parmentier, K., Hagel, P., De Boer, J., 2009. Decreasing eel stocks: Survival of the fattest? Ecol. Freshw. Fish 18, 197–214. https://doi.org/10.1111/j.1600-0633.2008.00337.x.
Benitez, J.-P., Dierckx, A., Rimbaud, G., Nzau Matondo, B., Renardy, S., Rollin, X., Gillet, A., Dumonceau, F., Poncin, P., Philippart, J.-C., Ovidio, M., 2022. Assessment of Fish Abundance, Biodiversity and Movement Periodicity Changes in a Large River over a 20-Year Period. Environments 9, 22. https://doi.org/10.3390/environments9020022.
Benitez, J.P., Nzau Matondo, B., Poignet, M., Dierckx, A., Vom Berge, C., Gelder, J., Ovidio, M., 2025. Rapport final annuel 2025 au Service Public de Wallonie (DGARNE/DNF-SP) de la Subvention 2024-2025 relative au suivi scientifique de la réhabilitation du saumon atlantique dans le bassin de la Meuse. Université de Liège,64 pages.
Bonhommeau, S., Chassot, E., Rivot, E., 2008. Fluctuations in European eel (Anguilla anguilla) recruitment resulting from environmental changes in the Sargasso Sea. Fish. Oceanogr. 2008, 17, 32–44. https://doi.org/10.1111/j.1365-2419.2007.00453.x.
Champkin, J.D., Bašić, T., Haubrock, P.J., Balzani, P., Sayer, C.D., George, L.K., Godard, M.J., Vilizzi, L., Copp, G.H., 2024. Short-term growth, movement and response of European eel Anguilla anguilla to re-meandering of a small English chalk stream. Knowl. Manag. Aquat. Ecosyst. 425 (2024) 23. https://doi.org/10.1051/kmae/2024021.
CITES, 2024. Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora. Appendices I, II and III, Annual Report of the Secretariat, CITES: Geneva, Switzerland, 79p.
Daufresne, M., Veslot, J., Capra, H., Carrel, G., Poirel, A., Olivier, J.-M., Lamouroux, N., 2015. Fish community dynamics (1985–2010) in multiple reaches of a large river subjected to flow restoration and other environmental changes. Freshw. Biol. 60, 1176–1191. https://doi.org/10.1111/fwb.12546.
Daverat, F., Limburg, K.E., Thibault, I., Shiao, J.C., Dodson, J.J., Caron, F., Tzeng, W.N., Iizuka, Y., Wickström, H., 2006. Phenotypic plasticity of habitat use by three temperate eel species, Anguilla anguilla, A. japonica and A. rostrata. Mar. Ecol. Prog. Ser. 308, 231–241. https://www.jstor.org/stable/24869966.
Delrez, N., Zhang, H., Lieffrig, F., Mélard, C., Farnir, F., Boutier, M., Donohoe, O., Vanderplasschen, A., 2021. European eel restocking programs based on wild-caught glass eels: Feasibility of quarantine stage compatible with implementation of prophylactic measures prior to scheduled reintroduction to the wild. J. Nat. Conserv. 59, 125933. https://doi.org/10.1016/j.jnc.2020.125933.
Denis, J., Mahé, K., Amara, R., 2022. Abundance and growth of the European eels (Anguilla anguilla Linnaeus, 1758) in small estuarine habitats from the eastern English Channel. Fishes 7 (5), 213. https://doi.org/10.3390/fishes7050213.
Drouineau, H.D., Castonguay, M., Mateo, M., Rochard, E., Verreault, G., Yokouchi, K., Lambert, P., 2018. Freshwater eels: A symbol of the effects of global change. Fish. Fish. 19, 903–930. https://doi.org/10.1111/faf.12300.
Félix, P.M., Costa, J.L., Monteiro, R., Castro, N., Quintella, B.R., Almeida, P.R., Domingos, I., 2020. Can a restocking event with European (glass) eels cause early changes in local biological communities and its ecological status? Glob. Ecol. Conserv. 21, e00884. https://doi.org/10.1016/j.gecco.2019.e00884.
Fernéndez-Gelgado, C., Hernando, J.A., Herrera, M., Bellido, M., 1989. Age and growth of yellow eels, Anguilla anguilla, in the estuary of the Guadalquivir River (south-west Spain). J. Fish Biol. 34, 561–570. https://doi.org/10.1111/j.1095-8649.1989.tb03335.x.
Feunteun, E., 2002. Management and restoration of European eel population (Anguilla anguilla): An impossible bargain. Ecol. Eng.18, 575–591. https://doi.org/10.1016/S0925-8574(02)00021-6.
Fox, J., 2017. Using the R Commander: A Point-and-Click Interface for R Chapman and CRC Press, Boca Raton, FL, USA. Available online.
Froese, R., 2006. Cube law, condition factor and weight-length relationships: history, meta-analysis and recommendations, J. Appl. Ichthyol. 22, 241–253, https://doi.org/10.1111/j.1439-0426.2006.00805.x.
Harrell, Jr.F.E., 2018. Hmisc: Harrell miscellaneous (Version 41-1) Cran.
Ibbotson, A., Smith, J., Scarlett, P., Aprahamian, M.W., 2002. Colonisation of freshwater habitats by the European eel Anguilla anguilla. Freshw. Biol. 47, 1696–1706. https://doi.org/10.1046/j.1365-2427.2002.00930.x.
ICES, 2018. Report of the Joint EIFAAC/ICES/GFCM Working Group on Eels (WGEEL) and Country Reports 2017–2018; ICES Scientific Reports; ICES Advisory Committee: Gdansk, Poland, 2018.
Jellyman, D.J., Arai, T., 2016. Juvenile eels: Upstream migration and habitat use. T. Arai (Ed.) Biology and ecology of anguillid eels (pp. 171–191). CRC Press.
Laffaille, P., Baisez, A., Rigaud, C., Feunteun, E., 2004. Habitat preferences of different European eel size classes in a reclaimed marsh: A contribution to species and ecosystem conservation. Wetlands 24, 642–651. https://doi.org/10.1672/0277-5212(2004)024[0642:HPODEE]2.0.CO;2.
Lobón-Cerviá, J., Utrilla, C.G., Rincón, P.A., 1995. Variations in the population dynamics of the European eel Anguilla anguilla (L.) along the course of a Cantabrian river. Ecol. Freshw. Fish 4,17–27. https://doi.org/10.1111/j.1600-0633.1995.tb00023.x.
Mann, R.H.K., 1982. The annual food consumption and prey preferences of pike (Esox lucius) in the River Frome, Dorset. J. Anim. Ecol. 51, 81–95. https://doi.org/10.2307/4312
Meunier, F.J., 1994. Données sur la croissance de l’anguille (Anguilla anguilla L.) dans le cours moyen du Rhin, région Alsacienne. Bull. fr. pêche piscic. 335, 133–144. https://doi.org/10.1051/kmae:1994010.
Moriarty, C., 1973. Studies of the eel Anguilla anguilla in Ireland. 2. In Lough Conn, Lough Gill and North Cavan Lakes. Ir. Fish. Invest., Ser. A 13, 1–13. http://hdl.handle.net/10793/242.
Moriarty, C., 1983. Age determination and growth of eels, Anguilla anguilla (L.). J. Fish Biol. 23, 257–264. https://doi.org/10.1111/j.1095-8649.1983.tb02903.x
Morin, A., Lamoureux, W., Busnarda, J., 1999. Empirical models predicting primary productivity from chlorophyll a and water temperature for stream periphyton and lake and ocean phytoplankton. J. N. Am. Benthol. Soc. 18, 299–307. https://doi.org/10.2307/1468446.
Naismith, I.A., Knights, B., 1988. Migrations of elvers and juvenile European eels, Anguilla anguilla L., in the River Thames. J. Fish Biol. 33,161–175. https://doi.org/10.1111/j.1095-8649.1988.tb05570.x.
Naismith, I.A., Knights, B., 1990. Modelling of unexploited and exploited population of eels, Anguilla anguilla (L.), in the Thames Estuary. J. Fish Biol. 37, 975–986. https://doi.org/10.1111/j.1095-8649.1990.tb03600.x.
Naismith, I.A., Knights, B., 1993. The distribution, density and growth of the European eel, Anguilla anguilla, in the freshwater catchment of the River Thames. J. Fish Biol. 42, 217–226. https://doi.org/10.1111/j.1095-8649.1993.tb00323.x.
Nzau Matondo, B., Backory, L., Dupuy, G., Amoussou, G., Oumarou, A.A., Gelder, J., Renardy, S., Benitez, J.-P., Dierckx, A., Dumonceau, F., Rollin, X., Ovidio M. 2023b. Space and Time Use of European Eel Restocked in Upland Continental Freshwaters, a Long-Term Telemetry Study. Fishes 8, 137. https://doi.org/10.3390/fishes8030137.
Nzau Matondo, B., Benitez, J.P., Dierckx, A., Rollin, X., Ovidio, M., 2020. An evaluation of restocking practice and demographic stock assessment methods for cryptic juvenile European eel in upland rivers. Sustainability 12, 1124. https://doi.org/10.3390/su12031124.
Nzau Matondo, B., Benitez, J.P., Dierckx, A., Renardy, S., Rollin, X., Colson, D., Baltus, L., Romain, V.R.M., Ovidio, M., 2021. What are the best upland river characteristics for glass eel restocking practice? Sci. Total Environ. 784, 147042. https://doi.org/10.1016/j.scitotenv.2021.147042.
Nzau Matondo, B., Delrez, N., Bardonnet, A., Vanderplasschen, A., Joaquim-Justo, C., Rives, J., Benitez, J.P., Dierckx, A., Séleck, E., Rollin, X., Ovidio, M., 2022. A complete check-up of European eel after eight years of restocking in an upland river: Trends in growth, lipid content, sex ratio and health status. Sci. Total Environ. 807, 151020. https://doi.org/10.1016/j.scitotenv.2021.151020.
Nzau Matondo, B., Fontaine, F., Detrait, O., Poncelet, C., Vandresse, S., Orban, P., Gelder, J., Renardy, S., Benitez, J.P., Dierckx, A., Dumonceau, F., Rollin, X., Ovidio, M., 2023a Glass Eel Restocking Experiments in Typologically Different Upland Rivers: How Much Have We Learned about the Importance of Recipient Habitats? Water 15, 3133. https://doi.org/10.3390/w15173133.
Nzau Matondo, B., Ovidio, M., 2016. Dynamics of upstream movements of the European eel Anguilla anguilla in an inland area of the river Meuse over the last 20 years. Environ. Biol. Fish 99, 223–235. https://doi.org/10.1007/s10641-016-0469-x.
Nzau Matondo, B., Ovidio, M., Lerquet, M., Colson, D., Sonny, D., 2024. Biology and Ecology of the European Eel as Revealed by an Original Sampling Technique Performed in a Deep and Large Riverine Ecosystem. Sustainability 16, 10607. https://doi.org/10.3390/su162310607.
Nzau Matondo, B., Ovidio, M., 2018. Decreased stock entering the Belgian Meuse is associated with the loss of colonisation behaviour in yellow-phase European eels. Aquat. Living Resour. (31), 7. https://doi.org/10.1051/alr/2017047.
Nzau Matondo, B., Séleck, E., Dierckx, A., Benitez, J.-P., Rollin, X., Ovidio, M., 2019. What happens to glass eels after restocking in upland rivers? A long-term study on their dispersal and behavioural traits. Aquat. Conserv. Mar. Freshw. Ecosyst. 29, 374–388.
Otjacques, W., De Laender, F., Kestemont, P., 2016. Discerning the causes of a decline in a common European fish, the roach (Rutilus rutilus L.): A modelling approach. Ecol. Model. 322, 92-100. https://doi.org/10.1016/j.ecolmodel.2015.12.002.
Ovidio, M., Tarrago-Bès, F., Nzau Matondo, B., 2015. Short-term responses of glass eels transported from UK to small Belgian streams. Ann. Limnol. Int. J. Limnol. 51,219–226. https://doi.org/10.1051/limn/2015016.
Pachla, L.A., Massaro, M.V., Reynalte-Tataje, D.A., Hartz, S.M., 2026. First Records of length–weight relationships for ten Fish species From the Middle Stretchofthe Uruguay River, Southern Brazil. J. Appl. Ichthyol. 2026:5687667. https://doi.org/10.1155/jai/5687667.
Philippart, J.C., Rimbaud, G., Gilles, C., Mercier, Ph, Ovidio, M., Piels, J., 2001. Convention d’études pour le suivi scientifique de la réhabilitation du saumon atlantique dans le bassin de la Meuse. Programme Meuse Saumon 2000. Rapport d’étape pour la période février-juillet 2001 au ministère de la Région wallonne. Direction Générale des Ressources Naturelles et de l’Environnement. Laboratoire de Démographie des Poissons et d’Aquaculture de l’Université de Liège, 78 pages + annexes (septembre 2001). https://orbi.uliege.be/bitstream/2268/160781/1/Rapportsaumon2001.pdf
Pike, C., Crook, V., Gollock, M., 2020. Anguilla anguilla. The IUCN Red List of Threatened Species 2020: E.T60344A152845178. 2020. Available online: (accessed on 12 February 2026).
Piper, A.T., Manes, C., Siniscalchi, F., Marion, A., Wright, R.M., Kemp, P.S., 2015. Response of seaward-migrating European eel (Anguilla anguilla) to manipulated flow fields. Proc. R. Soc. 282, 1098. https://doi.org/10.1098/rspb.2015.1098.
Poole, W.R., Reynolds, J.D., 1996. Age and Growth of Yellow Eel, Anguilla anguilla (L.), Determined by Two Different Methods. Ecol. Freshw. Fish 5, 86–95.
R Development Core Team R: A Language and Environment for Statistical Computing 2016 R Foundation for Statistical Computing Vienna, Austria.Available online: https://www.R-project.org/.
Righton, D., Piper, A., Aarestrup, K., Amilhat, E., Belpaire, C., Casselman, J., Castonguay, M., Díaz, E., Dörner, H., Faliex, E., Feunteun, E., Fukuda, N., Hanel, R., Hanzen, C., Jellyman, D., Kaifu, K., McCarthy, K., Miller, M.J., Pratt, T., Sasal, P., Schabetsberger, R., Shiraishi, H., Simon, G., Sjöberg, N., Steele, K., Tsukamoto, K., Walker, A., Westerberg, H., Yokouchi, K., Gollock, M., 2021. Important questions to progress science and sustainable management of anguillid eels. Fish Fish. 00, 1–27. https://doi.org/10.1111/faf.12549.
Russon, I.J., Kemp, P.S., Calles, O., 2010. Response of downstream migrating adult European eels (Anguilla anguilla) to bar racks under experimental conditions. Ecol. Freshw. Fish 19, 197–205. https://doi.org/10.1111/j.1600-0633.2009.00404.x.
Russon, I.J., Kemp, P.S., 2011. Advancing multi-species fish passage: Behaviour of adult European eel (Anguilla anguilla) and brown trout (Salmo trutta) in response to accelerating flow. Ecol. Eng. 37, 2018–2024. https://doi.org/10.1016/j.ecoleng.2011.08.005.
Sadler, K., 1979. Effects of temperature on the growth and survival of the European eel, Anguilla anguilla. L. J. Fish Biol. 15, 499–507. https://doi.org/10.1111/j.1095-8649.1979.tb03633.x.
Tesch, F.W., (-2003)-. The eel (5th ed.). Blackwell Science Ltd. doi.10.1002/9780470995389.
UE-Council of the European Communities, 2007. Council regulation (EC) no 1100/207 of 18 September 2007 establishing measures for the recovery of the stock of European eel. Off. J. Eur. Union L248, 17–23.
van den Thillart, G., van Ginneken, V., Korner, F., Heijmans, R., Van Der Linden, R., Gluvers, A., & Gluvers, A., 2004. Endurance swimming of European eel. J.Fish Biol.65, 312–318. https://doi.org/10.1111/j.0022-1112.2004.00447.x.
van Ginneken, V.J.T., Maes, G.E., 2005. The European eel (Anguilla anguilla, Linnaeus), its lifecycle, evolution and reproduction: a literature review. Rev. Fish Biol. Fish. 15, 367–398. Https://doi.org/10.1007/s11160-006-0005-8.
Vlietinck, K., Philippart J.C., Thirion, A., 2010. Eel Management Plan for Belgium. Besluit Van De Europese Commissie Van 5 January 2010 Houdende Goedkeuring Van Het Palingbeheerplan Voor België, Brussel, 198p..
White, E.M., Knights, B., 1997. Environmental factors affecting migration of the European eel in the rivers Severn and Avon, England. J. Fish Biol. 50,1104–1116. https://doi.org/10.1111/j.1095-8649.1997.tb01634.x.