Zebra Mussel, Dreissena polymorpha: Population Dynamics and Notes on Control Strategies in a Reservoir in Western Greece

ABSTRACT

Growth, mortality and yield were investigated in the zebra mussel, Dreissena polymorpha (PALLAS) from the Kastraki artificial reservoir, Central Greece. Allometric relationships were defined using shell length and total wet weight of the sampled individuals. The parameters of die Gompertz, von Bertalanffy and logistic growth curves (both length and weight) were estimated and gave L∞ = 4.05 cm, K = 0.808 per year, length-at-birth = 39 μg and weight-at-birth = 19 μm. The length-frequency distribution showed 5 distinct modes from which the last 2 (IV and V) are considered the same due to high similarity and therefore, die longevity of the species (t_λ) is about 4 years. The natural mortality (M) is considered equal to die total mortality (Z) because die population is commercially unexploited and thus, fishing mortality is 0. The Z was estimated to be about 2.15 according to both die Wetherall method and the length converted catch curve analysis. Control strategies of this population include either the treatment with disinfectants (chlorine) during die reproduction period of die species or the introduction of known predators in the reservoirs.

Key Words:

• Zebra mussel
• Dreissena polymorpha
• growth
• mortality
• yield
• control