In the non-response group 83% reported not fishing themselves, compared to 64% of respondents. There were significant differences between the groups on how many days they had been fishing with the non-responders fishing the least (MannWhitney’s U = 8198, z = −2.25, p = 0.02). The number of co-owners in each common property was significantly higher for the non-response group with a median of 10 vs. 5 people (U = 720, z = −2.70, p < 0.01). There were no differences between the two groups on the questions of interest in salmon management issues, a statement about how well the local river owner association worked, type of property regime, length of fishing right, ownership on both banks of the river, catch possibility on their fishing right, net income from salmon fishing, sex, age, or education level. The tests suggest a possible underrepresentation in the response by landowners in those common properties with many co-owners. Given only 12 answers from landowners in common properties and the possibility of measurement error in this question4, the results are discussed with potential bias in mind.