Introduced alien signal crayfish (Pacifastacus leniusculus) in Finland - uncontrollable expansion despite numerous crayfisheries strategies
Laen...
Kuupäev
2018
Kättesaadav alates
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
EDP Sciences
Abstrakt
In Finland, massive signal crayfish introductions started towards the end of 1980s, with an
estimated total of 2.2 million signal crayfish been stocked before year 2016. During that period, Finnish
fisheries authorities have implemented three national management strategies setting guidelines for the
crayfish introductions. The main aims of the strategies have been conservation of native noble crayfish
stocks and a controlled spreading of the alien signal crayfish within a designated region. In this study, we
report the current distribution of signal crayfish in Finland in comparison to the guidelines set in these three
national strategies. The present distribution area of the signal crayfish covers most of the Southern Finland.
The signal crayfish has been introduced with a stocking permits to over 480 water bodies. In addition, there
have been numerous stockings without permits, which are often next to the region designated for signal
crayfish. Based on the results, we conclude that crayfisheries strategies adopted in Finland have only had
limited effect on the spread of signal crayfish. We presume that main causes for the uncontrolled spreading
of the signal crayfish in Finland have been lack of strict official supervision and general lack of awareness
about the risks associated with the alien species spreading.
We have been kindly assisted by EU LIFE + CrayMate (LIFE12 INF/FI/233) in our attempts to understand complicated nature related policies. TJR and FE have been funded by Maj & Tor Nessling Foundation. We also thank Mr. Markku Pursiainen and numerous other people from Finnish Natural Resource Institute for collecting and process- ing crayfish data. We are also grateful for people in local Centres for Economic Development, Transport and the Environment for access to recent signal crayfish introduction and observation data.
We have been kindly assisted by EU LIFE + CrayMate (LIFE12 INF/FI/233) in our attempts to understand complicated nature related policies. TJR and FE have been funded by Maj & Tor Nessling Foundation. We also thank Mr. Markku Pursiainen and numerous other people from Finnish Natural Resource Institute for collecting and process- ing crayfish data. We are also grateful for people in local Centres for Economic Development, Transport and the Environment for access to recent signal crayfish introduction and observation data.
Kirjeldus
Märksõnad
dispersal, introduction, management, non-native crayfish, strategy, articles