| Summary: | Biological invasions are of increasing global concern. They impact on biodiversity and
may result in high economic loss. This demands improvement in knowledge of the dynamics of
species dispersal with the goal of preventing future invasions, and predicting and
reducing undesirable impacts. This study reports on non-indigenous macroinvertebrate
species (NIMS) which have invaded Lithuanian fresh waters. Fifteen NIMS have been recorded
during a 12-year study. They include one cnidarian, two molluscan and twelve crustacean
species. The deliberate introduction of peracaridans and crayfish for fishery and
aquaculture enhancement has substantially contributed to the current NIMS composition.
Invaders of Ponto-Caspian origin are dominant, and the collector-gatherers are the largest
group with respect to feeding mode. Current NIMS distributions, the history of their
primary invasion and patterns of local dispersal are analysed. The main invasion vectors
have been inland shipping and deliberate introductions, while secondary spread proceeded
both naturally and by various human mediated vectors. The current distribution of most
NIMS may remain constant in the future, whilst further expansion of a few NIMS, which
possess good dispersal abilities and are well-adapted to freshwater environments, seems
very probable. Using multivariate analysis of data from water bodies with established
peracaridan invaders, allowed predictions on which unsurveyed water bodies could contain
such invaders. Invasions of new NIMS and diversification of donor areas, pathways and
vectors are considered.
|
|---|
