Life in an unstable house: community dynamics in changing mussel beds
In: Hydrobiologia. Springer: The Hague. ISSN 0018-8158; e-ISSN 1573-5117, meer
|  |
| Trefwoorden |
Monitoring
PNE, Russia, White Sea
Population dynamics
Temporal variations > Long-term changes
Mytilus edulis Linnaeus, 1758 [WoRMS]
White Sea [Marine Regions]
Marien/Kust |
| Author keywords |
Mussel beds; Community dynamics; White Sea |
| Abstract |
Mussels are ecosystem engineers, and fluctuations in their abundance and population structure could be important to the associated community. There is, however, little understanding of this connection. In the present study, based on quantitative monitoring (1997–2011) of three mussel beds in a fjord-like White Sea bay, two hypotheses were tested: (1) mussel assemblages are temporally unstable and local population fluctuates cyclically as a result of negative adult–juvenile interactions; and (2) oscillations in mussel size-structure are correlated with changes in the associated community structure. A negative correlation found between the abundance of small (length < 21 mm) and large (length > 20 mm) mussels suggests that adult mussels indeed suppress recruitment. Such interaction implies an auto-oscillatory pattern of population dynamics, with Large- and Small-dominated stages temporally replacing each other. This cyclic pattern was clearly revealed for one mussel bed only, but long-term replacement of the Large-dominated stage by the Small-dominated stage was revealed for the other two assemblages also. In general, temporal variations of mussel populations were significantly correlated with the dynamics of the associated community, although several abundant taxa (Tubificoides benedii, Littorina saxatilis, Macoma balthica, and Gammaridae) were insensitive to mussel changes. In contrast, filamentous algae and mud snails Hydrobia ulvae tended to be more abundant during the Large-dominated stage, whereas polychaetes Dipolydora quadrilobata were most abundant during the Small-dominated stage. Several other abundant “sensitive” taxa were obviously dependent on algal bloom. Thus, mussel beds are unstable systems, whose dynamics are shaped not only by the ecosystem engineer but also by the associated community. |
|
