New policy recommendations for managing invasive fish

Stocking of salmon outside their natural habitat should be avoided. That sounds obvious, but the fact is that in Europe it’s common to stock fish such as rainbow trout and brown trout in streams where they normally aren’t found. For this reason, the SalmoInvade research project has now developed policy recommendations for the management of invasive fish in the salmon family, or salmonids.

Salmonids are among the most significant fish species in Europe, from both an economic and cultural perspective. They are an important species for the growing aquaculture industry, but also for both recreational and the commercial fishing. For this reason, salmon have been stocked to one degree or another in many places where they normally are not found, which can have major consequences for both natural fish stocks and the entire ecosystem.

Jörgen Johnsson, professor of animal ecology, is the coordinator of the SalmoInvade research project, which is behind the new recommendations.

Why have you developed policy recommendations?

“There are shortcomings in the management and regulation of the spread of invasive salmonids in most countries in Europe. There is also a large variation among European countries in this management, which varies from more central control and regulation in Scandinavia to stronger local influence in continental Europe. There are also shortcomings in how existing regulations are observed in all European countries. So we felt that a common European approach was needed to analyse and try to improve the situation.”

What is required for regulations to be followed?

“Closer cooperation and dialogue between regulatory agencies, researchers and those responsible locally as well as an improved transfer of knowledge so local stakeholders feel motivated and involved in applying the recommendations and understanding why they are needed.”

What can ordinary people do to have an impact?

“They can do such things as restore natural habitats to strengthen natural salmon stocks instead of relying on artificial stocking. Anglers and other nonprofit organisations in Sweden are already making major contributions towards improving natural habitats, but there’s always more that can be done. In continental Europe people often look on stocking more favourably, in part because the natural salmonid stocks are often absent. Dissemination of knowledge is also very important. In all the countries studied, we’ve found that ordinary people have a rather poor understanding of which salmonid species are native and which ones are introduced. That makes it difficult to get involved in protecting native species.”

Policy recommendations at a glance:

  • Improve the monitoring, reporting and evaluation of salmonid stocking
  • Introduce strict guidelines for stocking of invasive salmonids to preserve biodiversity
  • Provide information and support to local and regional decisionmakers and agencies to create better regulations and evaluation methods
  • Take into account the variation in how people in the various European countries value native salmonids in drawing up strategies for their conservation
  • Improve the dialogue between the scientific community, the public and decisionmakers to create preconditions for biodiversity

Link to the SalmoInvade Policy brief