Exploring the evidence base for reptile conservation actions: gaps, biases and research priorities

With over 21% of reptile species threatened with extinction, we urgently need to ensure conservation actions to protect and restore populations are informed by relevant, reliable evidence. Here we examine the geographic and taxonomic distribution of 707 studies synthesised in Conservation Evidence’s Reptile Conservation synopsis testing the effects of actions to conserve reptiles. We found that more studies were conducted in countries with higher GDP per capita and more reptile species, clustered in the USA (43%) and Australia (15%), with large gaps across South-East Asia, South America, and Sub-Saharan Africa. Taxonomically, 46% of 92 (mostly Squamata) families were not studied at all. Although Squamata and Testudines both featured in approximately 50% of studies, the eight most-studied species were Testudines (36% of studies) with significantly more studies per species. There were significantly more studies for species with more Wikipedia page views, significantly fewer studies for Data Deficient species than other IUCN Red List categories, and no significant relationship between the number of studies and evolutionary distinctiveness of species.Our results highlight pressing evidence needs, including for underrepresented and threatened species and regions (e.g., Evolutionarily Distinct and Globally Endangered reptiles in South America, Sub-Saharan Africa, and South-East Asia). To overcome evidence gaps and a lack of basic ecological data, we also need to explore how the effects of actions transfer across taxa and regions. We call for greater efforts to strategically increase and coordinate the testing and reporting of the effects of conservation actions to inform more effective and efficient conservation globally.