Is it becoming harder to secure reviewers for peer review? A test with data from five ecology journals

Background There is concern in the academic publishing community that it is becoming more difficult to secure reviews for peer-reviewed manuscripts, but much of this concern stems from anecdotal and rhetorical evidence.Methods We examined the proportion of review requests that led to a completed review over a 6-year period (2009-2015) in a mid-tier biology journal (Molecular Ecology). We also re-analyzed previously published data from four other mid-tier ecology journals (Functional Ecology, Journal of Ecology, Journal of Animal Ecology, and Journal of Applied Ecology), looking at the same proportion over the period 2003 to 2010.Results The data from Molecular Ecology showed no significant decrease through time in the proportion of requests that led to a review (proportion in 2009 = 0.47 (95 % CI = 0.43 to 0.52), proportion in 2015 = 0.44 (95 % CI = 0.40 to 0.48)). This proportion did decrease for three of the other ecology journals (changes in proportions from 2003 to 2010 = -0.10, -0.18, and -0.09), while the proportion for the fourth (Functional Ecology) stayed roughly constant (change in proportion = -0.04).Conclusions Overall, our data suggest that reviewer agreement rates have probably declined slightly but not to the extent suggested by the anecdotal and rhetorical evidence.