Counting butterflies : are old-fashioned ways of recording data obsolete?

Abstract

Citizen Science projects aim to make data entry as easy as possible and often provide online data recording or data recording with an App. However, many participants cannot or do not want to use these possibilities and record their data the "old-fashioned" way with pen on paper. We ask whether the quality of data recorded in the "old-fashioned" way (transect walkers record their data with pen on paper) is of the same, better or worse quality than data recorded "online" (transect walkers enter their data via an online tool). We use the project "Butterfly Monitoring Germany" as an example, where we identify three different types of volunteers: those who enter their data online, those who send their data to the project coordination via email in different formats and those who send their data to the project coordination via ordinary mail. We observed minor quantitative differences for transect walkers not entering their data online but significant qualitative differences. Transect walkers who send their data via email record significantly more data for some rare or difficult to determine species. This is essential to properly calculate these species' trends. In addition, the results of a questionnaire showed that "old fashioned" transect walkers did not use the online data entry because (i) data entry takes too long, (ii) is too cumbersome, (iii) they have bad or no internet connection or (iv) lack of technical capabilities. Accounting for different preferences of Citizen Scientists, different ways of data-submission should be made available (e.g. online, via app, or the old-fashioned way on paper). For the future, projects that collect large amounts of Citizen Science data should further develop low-threshold input data pipelines.