Figure 1. Mean insect biomass catch per day as a function of year, based on the ‘raw’ data from Hallmann et al. 2017.
Figure 2. Mean insect biomass catch per day as a function of year. Blue symbols (n=15) represent the years 1989-2006, red symbols (n=10) represent the years 2007-2016.
Figure 3. Total yearly collected biomass (g) as a function of the total number of catching days. The two equations are the linear relationship fitted through the years 1989-2006 (blue, n=15), and 2007-2016 (red, n=10). It seems as if there exists a structural difference in catch efficiency between the first years of research and the last years of research.