Tracking trends at individual sites, rather than pooling trends among sites, puts the emphasis on detecting individual site trends rather than regional trends. Note, this would not necessarily have to be limited to cover board surveys, but for practical purposes they would be emphasized as most appropriate for citizen participation. Note too, that once the bugs in the system are worked out there is little reason to limit participation only to North America, as similar issues and problems exist world-wide. The reason lies in our goals. Because of the relative longevity and low fecundity of salamanders, small changes in population size may reflect significant long-term environmental changes.
Power is the ability of a monitoring program to detect a trend if one is really going on.
In the data presented here, all but 3 studies and 1 borderline case, meet that criteria. No particular pattern of association with salamander species, geographic regions, techniques, appears evident. These numbers are even more impressive given that the objective of most of the authors was not to necessarily minimize sampling noise and that we made no attempt to remove the effects of any population changes occurring in the longer running studies. However, it should be noted that the 2 longest term studies took their samples at the same time of year every year. Summary of power analyses for 23 studies of plethodontid salamanders.