Recreation effect threshold articles by bird and mammal orders (a) bird and (b) mammal orders studied in papers that identified an effect threshold. Several articles contained more than one order, thus, the total number of articles sums to more than all the threshold effects papers.

 
 
  Part of: Dertien JS, Larson CL, Reed SE (2021) Recreation effects on wildlife: a review of potential quantitative thresholds. Nature Conservation 44: 51-68. https://doi.org/10.3897/natureconservation.44.63270