Belpaire, C.

Van Thuyne, G.

Verreycken, H.

Open Marine Archive

Science Facing Aliens – Brussels, May 11th 2009 24 
Non-indigenous freshwater fishes in Flanders: status, trends and risk 
assessment 
 
Verreycken Hugo *, Van Thuyne Gerlinde, Belpaire Claude 
 
Research Institute for Nature and Forest (INBO) Duboislaan 14 1560 Hoeilaart  
* Corresponding author Tel. 02 658 04 26 E-mail: hugo.verreycken<at>inbo.be  
 
At least eighteen non-indigenous freshwater fish species were reported to occur in 
the wild within the territory of Flanders. Nine are considered naturalized while the 
others are acclimatized and do not form self sustaining populations. Nine of the 
introductions occurred prior to 1950, with the other nine species introduced since 
then. This contribution reviews the available information on these introductions, and 
evaluates a decade of data from fisheries surveys to assess the recent development 
of these non-indigenous populations. Gibel carp Carassius gibelio and topmouth 
gudgeon Pseudorasbora parva are the most widespread of the non-indigenous 
species in Flemish waters, and both continue to expand their ranges. A reduction in 
range has been observed in brown bullhead Ameiurus nebulosus only. Only four 
species occur in all eleven river basins while eight species are restricted to one or 
two basins and often only one specimen was found during fish stock assessments. 
We also discuss non-indigenous fish species that are likely to colonize Flanders 
inland waters in the near future. For all non-indigenous freshwater fish species 
present and expected to appear soon, different risk analysis tools (FISK and ISEIA) 
were used to screen these species for their possible invasiveness. Although scores 
from FISK and ISEIA differ for some species, gibel carp and topmouth gudgeon were 
in both assessments classified as ‘highest risk’ species in relation to their potential 
invasiveness.  
 
Verreycken, H., Anseeuw, D., Van Thuyne, G., Quataert, P. and Belpaire, C., 2007: The non-
indigenous freshwater fishes of Flanders (Belgium): review, status and trends over the 
last decade. – J. Fish Biol. 71 (Supplement D), 160–172.  
Verreycken, H., Vandenbergh, K., Vilizzi, L. and Copp, G.H., (in prep): Initial application of 
the Fish Invasiveness Screening Kit (FISK) to freshwater fishes in Flanders 
 
 


Non-indigenous freshwater fishes in Flanders: status, trends and risk assessment

Abstract

Similar works

Full text

Available Versions

Open Marine Archive