Active movement to coarse grained sediments by globally endangered freshwater pearl mussels (Margaritifera margaritifera)

Research output: Contribution to journalResearch articleContributedpeer-review



The freshwater pearl mussel Margaritifera margaritifera is an endangered bivalve which is usually regarded as sedentary, although individual movement has been observed both vertically and horizontally. Little is known about the causes and rates of mussel movement. The objective of this study was to test the effect of microhabitat characteristics on the horizontal movement distance and rates of freshwater pearl mussels. A total of 120 mussels (length range 40–59 mm) were marked individually with passive integrated transponder tags, placed in stream microhabitats differing in their sediment composition and monitored biweekly over a period of 10 weeks. Mussels situated in sand-dominated habitats had a significantly higher mean movement rate (3.2 ± 4.2 cm/day, mean ± SD) than mussels situated in gravel-dominated (1.9 ± 2.7 cm/day) or stone-dominated habitats (1.8 ± 3.2 cm/day). The direction of the movements appeared random; however, an emigration from sandy habitats was observed, probably to avoid dislodgment from these hydraulically unstable habitats. This study demonstrates that freshwater pearl mussels can actively emigrate from unsuitable microhabitats. Once suitable streams with respect to physical, chemical, and biological quality were identified, it is therefore only necessary to identify suitable mesohabitats (area of 10–30 m2) when reintroducing or relocating mussels.


Original languageEnglish
Pages (from-to)985-999
Number of pages15
Issue number4
Publication statusPublished - 11 Jan 2023

External IDs

Mendeley adaa48cf-f1b8-3083-9a89-27034bf41e19
WOS 000912315200002
ORCID /0000-0002-6048-6984/work/142240085
ORCID /0000-0003-2159-9609/work/142254796
ORCID /0000-0002-8250-0986/work/150330198


Sustainable Development Goals

ASJC Scopus subject areas


  • Behavior, Fine sediment, Horizontal locomotion, Microhabitat requirements, PIT-tag

Library keywords