Data collection systems and methodologies for the inland fisheries of Europe

Inland fisheries are important sources of ecosystem services contributing to human diet, health, well-being and economies. The evaluation of the importance and value of inland fisheries is one of the biggest challenges for its development. To develop the inland fisheries data collection, we reviewed the current status of data collection in European countries and provided five detailed country examples. The level and methods of inland fisheries data collection in Europe were highly variable. Some countries did not collect any data on recreational fishing, or it was collected only from specific areas, or only the number of licenses sold was recorded. Data collection from catches of diadromous species was most common and harmonized among countries and in particular, Atlantic salmon Salmo salar were recorded. When data from other fish species were also nationally collected, the methods used included postal or telephone recall surveys using a sample of citizens of the country. More detailed surveys were used to assist national surveys, or were used independently, in specific sites of importance using various methods, like postal surveys targeted to fishing license holders, online reporting of catches, or catch reports and logbooks. Many countries provided fishing license buyers with catch return forms or logbooks to be filled at fishing occasions and/or returned in the end of the fishing season. Commercial inland fisheries did not exist, or were very limited, in many European countries. In countries where commercial fishing was important, in most cases the fishers were registered and obliged to report their catches. The reliability of self-reporting of commercial catches was questioned in some cases. There was a trend towards webbased online reporting of inland fisheries data, which some countries were already using. The specific country examples give detailed description of data collection, focusing on: 1) country-wide postal survey (Finland) and 2) web-based survey and development of citizen science approach (Denmark). Example 3) from Ireland focuses on recreational salmonid fishing and conservation limits. There are two examples based on logbook returns: 4) one strict system, which is considered to work well (Czech Republic) and 5) one less controlled system, currently not producing reliable results, and under development (Croatia). Case studies were provided in each country example. Finally, the authors discuss the important aspects of inland fisheries data collection and review the methods to provide recommendations.