Environmental Factors and Seasonal Variation in Density of Mussel Larvae (Mytilus edulis) in Danish Waters


Mussel larval densities may fluctuate considerably on both small spatial and short temporal scales. So far, only few and scattered data on the occurrence of mussel larvae have been reported from Danish waters. However, seasonal variation in density of blue mussel (Mytilus edulis) larvae as related to environmental factors (temperature, salinity, phytoplankton biomass) is basic information of relevance for future line-mussel farming in Danish waters. Here we report on the density of mussel larvae in a number of potential farming sites in the inner Danish waters. The mussel larval density measured in Skive Fjord, an eutrophicated inner branch of Limfjorden, during a period of 20 years, from 1989 to 2009, along with corresponding temperatures and chlorophylla, makes up the most important series of data reported here. In most years, a pronounced spring density peak and a subsequently lower autumn peak could be seen in Skive Fjord, but most conspicuous in the period 1993 to 2002 where the mean maximum spring larval density was 319 ± 260 ind·l-1. Further, data on mussel larval densities have been recorded on 4 locations in the Great Belt region: Kerteminde Bay in 2008 to 2011, and in 2008 at 3 other locations: Musholm Bay, Svendborg Sund, and Horsens Fjord. The maximum spring densities in the studied waters were observed in Skive Fjord, typically in May, whereas 10 to 100 times lower peak densities were found at the other locations studied. The reported observations show that mussel larvae are omnipresent in the studied areas and it is suggested that the larval density is sufficient forrecruitment to future line-mussel farms.

Share and Cite:

Riisgård, H. , Lundgreen, K. and Pleissner, D. (2015) Environmental Factors and Seasonal Variation in Density of Mussel Larvae (Mytilus edulis) in Danish Waters. Open Journal of Marine Science, 5, 280-289. doi: 10.4236/ojms.2015.53023.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] Seed, R. (1976) Ecology. In: Bayne, B.L., Ed., Marine Mussels: Their Ecology and Physiology, Cambridge University Press, Cambridge, 13-65.
[2] Savage, R.E. (1956) The Great Spatfall of Mussels in the River Conway Estuary in Spring 1940. Fisheries Investigations Series II, 20, 1-21.
[3] Dare, P.J. (1976) Settlement, Growth and Production of the Mussel, Mytilus edulis L., in Morecambe Bay, England. Fisheries Investigations Series II, 28, 1-25.
[4] Jorgensen, C.B. (1981) Mortality, Growth, and Grazing Impact of a Cohort of Bivalve Larvae, Mytilus edulis L. Ophelia, 20, 185-192. http://dx.doi.org/10.1080/00785236.1981.10426570
[5] Bayne, B.L. (1965) Growth and the Delay of Metamorphosis of the Larvae of Mytilus edulis. Ophelia, 2, 1-47. http://dx.doi.org/10.1080/00785326.1965.10409596
[6] Riisgard, H.U., Randlov, A. and Kristensen, P.S. (1980) Rates of Water Processing, Oxygen Consumption and Efficiency of Particle Retention in Veligers and Young Post-Metamorphic Mytilus edulis. Ophelia, 19, 37-47. http://dx.doi.org/10.1080/00785326.1980.10425505
[7] Jespersen, H. and Olsen, K. (1982) Bioenergetics in Veliger Larvae of Mytilus edulis L. Ophelia, 21,101-113. http://dx.doi.org/10.1080/00785236.1982.10426580
[8] Sprung, M. (1984) Physiological Energetics of Mussel Larvae (Mytilus edulis). I. Shell Growth and Biomass. Marine Ecology Progress Series, 17, 283-293. http://dx.doi.org/10.3354/meps017283
[9] Gosling, E. (2003) Bivalve Molluscs. Biology, Ecology and Culture. Fishing News Books, Blackwell, 443. http://dx.doi.org/10.1002/9780470995532
[10] Thorson, G. (1961) Length of Pelagic Larval Life in Marine Bottom Invertebrates as Related to Larval Transport by Ocean Currents. In: Sears, M., Ed., Oceanography, American Association for the Advancement of Science, Washington DC, 67, 455-474.
[11] Fotel, F.L., Jensen, N.J., Wittrup, L. and Hansen, B.W. (1999) In Situ and Laboratory Growth by a Population of Blue Mussel Larvae (Mytilus edulis L.) from a Danish Embayment, Knebel Vig. Journal of Experimental Marine Biology and Ecology, 233, 213-230.
[12] Dolmer, P. and Frandsen, R.P. (2002) Evaluation of the Danish Mussel Fishery: Suggestions for an Ecosystem Management Approach. Helgoland Marine Research, 56, 13-20.
[13] Dolmer, P. and Stenalt, E. (2010) The Impact of the Adult Blue Mussel (Mytilus edulis) Population on Settling of Conspecific Larvae. Aquaculture International, 18, 3-17. http://dx.doi.org/10.1007/s10499-009-9266-2
[14] Dinesen, G.E., Timmermann, K., Roth, E., Markager, S., Ravn-Jonsen, L., Hjorth, M., Holmer, M. and St?ttrup, J.G. (2011) Mussel Production and Water Framework Directive Targets in the Limfjord, Denmark: An Integrated Assessment for Use in System-Based Management. Ecology and Society, 16, 26. http://dx.doi.org/10.5751/ES-04259-160426
[15] Riisgard, H.U., Andersen, P. and Hoffmann, E. (2012) From Fish to Jellyfish in the Eutrophicated Limfjorden (Denmark). Estuaries and Coasts, 35, 701-713. http://dx.doi.org/10.1007/s12237-012-9480-4
[16] Petersen, J.K., Hasler, B., Timmermann, K., Nielsen, P., T?rring, D.B., Larsen, M.M. and Holmer, M. (2014) Mussels as a Tool for Mitigation of Nutrients in the Marine Environment. Marine Pollution Bulletin, 82, 137-143. http://dx.doi.org/10.1016/j.marpolbul.2014.03.006
[17] Riisgard, H.U., Lundgreen, K. and Larsen, P.S. (2014) Potential for Production of “Mini-Mussels” in Great Belt (Denmark) Evaluated on Basis of Actual Growth of Young Mussels Mytilus edulis. Aquaculture International, 22, 859-885. http://dx.doi.org/10.1007/s10499-013-9713-y
[18] Riisgard, H.U., Lundgreen, K. and Larsen, P.S. (2012) Field Data and Growth Model for Mussels Mytilus edulis in Danish Waters. Marine Biology Research, 8, 683-700.
[19] Riisgard, H.U., B?ttiger, L. and Pleissner, D. (2012) Effect of Salinity on Growth of Mussels, Mytilus edulis, with Special Reference to Great Belt (Denmark). Open Journal of Marine Science, 2, 167-176. http://dx.doi.org/10.4236/ojms.2012.24020
[20] Larsen, J.B., Frischer, M.E., Ockelmann, K.W., Rasmussen, L.J. and Hansen, B.W. (2007) Temporal Occurrence of Planktotrophic Bivalve Larvae Identified Morphologically and by Single Step Nested Multiplex PCR. Journal of Plankton Research, 29, 423-436. http://dx.doi.org/10.1093/plankt/fbm027
[21] Larsen, P.S., Lundgreen, K. and Riisg?rd, H.U. (2013) Bioenergetic Model Predictions of Actual Growth and Allometric Transitions during Ontogeny of Juvenile Blue Mussels Mytilus edulis. In: Nowak, J. and Kozlowski, M., Eds., Mussels: Ecology, Life Habits and Control, Nova Science, New York, 101-122.

Copyright © 2023 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.