Importance of non-journal literature in providing evidence for predator conservation

The literature other than scientific journals (non-journals) is a valuable, but scattered and rarely used, source of evidence of the effectiveness of interventions applied for protection from mammalian predators. This study describes how journals and non-journals differ in relation to study designs, types of interventions, predator species, countries, and publication bias. I collected 411 journal cases (226 publications) and 97 non-journal cases (64 publications) covering the period 1955–2020, five study designs, six interventions, 28 species and 50 countries. Non-journals were important for two predators (leopard Panthera pardus and snow leopard P. uncia) and four countries (Canada, India, Russia and Sri Lanka). These species and countries have been affected by human-predator conflicts and the use of non-journals should become a habitual practice to mitigate conflicts. Information on other species and countries, and all study designs and interventions, was provided mostly or only in peer-reviewed journals. This study helps make the use of non-journals easier for researchers and conservation practitioners by providing and explaining a list of relevant literature and online resources.