Water Framework Directive Fish Monitoring Programme

The Water Framework Directive is European Union legislation that was brought into Irish law in 2003. Its main purpose is for member states to manage their water resources and protect aquatic ecosystems. In doing so, it is each country’s responsibility to improve and prevent deterioration the water quality status of all waterbodies to at least “good” status.

Are our waters clean?

The Environmental Protection Agency (EPA) assigns status to Ireland’s waterbodies on the basis of different biological elements. In simple terms, these include phytoplankton (tiny free-living plants), macrophytes (large plants), phytobenthos (tiny plants attached to rocks and other surfaces), benthic macroinvertebrates (bottom dwelling insects and other creatures) and fish. Inland Fisheries Ireland supplies fish status information to the EPA.

Inland Fisheries Ireland began surveying and monitoring fish in 2007 as part of a comprehensive three-year rolling WFD programme. Over 300 waterbodies have been included on Ireland’s rivers, lakes and transitional waters.

Fish tell a story

Fish information is collected at sites within each waterbody, looking at three important things, biodiversity (the fish species present), abundance (the number of each fish caught) and age structure (a breakdown of their ages). Using this information we can gauge water quality based on fish community health at a site. This is done by asking questions such as do we see the fish we expect to see? Are they in healthy numbers and are there good numbers of young and old fish present. This can then be used to assign a ‘fish ecological status’ to each waterbody. The Water Framework Directive sets a five class scale (high, good, moderate, poor and bad ecological status).

Once Member States have determined the ecological status of their water bodies, ongoing monitoring can be used to track change and make recommendations for improvement.

How do we do it?

Fish sampling is carried out using a mixture of standard European methods, including electrofishing on rivers and netting on lakes and estuaries. We use fish aging techniques to learn more about each species.