"Variation in space and time can cause a significant deviation in the monitoring results, which may lead to incorrect conservation policy decisions," added Dr Klaus Henle from UFZ and coordinator of SCALES. "Therefore increasing awareness of the spatial or temporal scale at which monitoring has been performed can be of crucial importance!"
To optimize the monitoring practices, the scientists have proposed a range of recommendations. For most monitoring programs, the best data type to be collected is quantitative (count) data, such as number of individuals, which provide an early warning for conservation and policy. Further, monitoring could optimize resource allocation between independent monitoring sites. Importantly, even low variation between sites or years can induce spurious conclusions; hence repetitive sampling of the same sites within a year should be the rule.
In case of limited manpower, Schmeller and colleagues recommend an increase in the number of monitoring samples, even at the expense of the size of each sample. Further, more collaborations between monitoring programs at different scales need to be established, so that the sampled data may be integrated and re-used.
Finally, monitoring coordinators have to make special efforts to attract volunteers. Coordinators need to keep in mind several important points: 1) the specific characters of the local community; 2) having a recruitment strategy for volunteers interested in monitoring; 3) maintaining good communication with the volunteers; 4) having low hierarchies and treat volunteers with respect, and 5) making links to other voluntary organizations to add value to the work. Schmeller adds: "There is no one clear recipe to recruit and keep volunteers, but what is important is to keep in mind that the volunteers sacrifice their spare time for monitoring activities, which are of interest to all society!"