Removing the highly invasive clicker barb (Pseudorasbora parva, also known as the topmouth gudgeon) from a UK lake has resulted in an improvement in the population of native fish species, according to the results of a study published in the most recent issue of the journal Ecology of Freshwater Fish.
Removing the highly invasive clicker barb (Pseudorasbora parva, also known as the topmouth gudgeon) from a UK lake has resulted in an improvement in the population of native fish species, according to the results of a study published in the most recent issue of the journal Ecology of Freshwater Fish.
Robert Britton, Gareth Davies and Matt Brazier conducted this exercise in a small lake located in the Lake District, which held roach (Rutilus rutilus), common bream (Abramis brama), tench (Tinca tinca) and common carp (Cyprinus carpio) along with the invasive barb.
The authors removed the non-target species using seine nets, identified, measured, counted and weighed them before temporarily relocating them while fish poison (whose active ingredients were rotenone and piperonylbutoxide) was applied to the lake.
Because of the difficulty in removing the roach, the authors left many of them in place to be poisoned and subsequently reintroduced roach into the lake after the eradication exercise.
Prior to the exercise, the clicker barb was the most abundant fish in the lake, but the exercise was judged successful after no more barbs were found post-poisoning.
The authors compared the populations of the roach and common bream prior to and for three years after the eradication exercise, and found that these populations experienced faster growth, and increased estimates of abundance and production.
The authors add, iven invasive species eradication is often viewed as a controversial and almost impossible goal due to its expense, difficulty of success and imposition of collateral damage, then this finding is important in demonstrating eradication can also provide some benefits for surviving populations of native fishes.
For more information,see the paper: Britton, JR, GD Davies and M Britton (2009) Eradication of the invasive Pseudorasbora parva results in increased growth and production of native fishes. Ecology of Freshwater Fish 18, pp. 8"14.