Changes in enclosure use and basking behaviour associated with pair housing in Tokay geckos (Gekko gecko)

Due to often insufficient information, reptiles suffer welfare issues and increased mortality in captivity. In particular, the impact of the social environment remains poorly understood, despite evidence suggesting its’ importance for welfare in a wide range of social animals. The current study investigated how pair housing changes enclosure use, basking and hiding behaviour in tokay geckos (Gekko gecko). While the captive conditions and husbandry procedures employed in this study align with existing literature recommendations, they have not been previously evaluated for their suitability for this particular species. The results show that, when socially deprived, lizards were more likely to move and hide before feeding. Furthermore, males were more likely to be found at the front than females during pair housing but not during single housing. Finally, contrary to single housing, enclosure temperature had no effect on the probability to move and hide behind a shelter during pair housing. Consistently, lizards were more likely to bask after feeding across housing conditions, and females were more likely to bask before their first clutch. Together, pair housing decreases movement and hiding in relation to human presence (feeding), which might indicate that pair housing improves tokay gecko welfare and suggest that the presence of a conspecific should be considered to improve welfare policies in social reptiles. This study serves as a baseline for future research into how enclosure furnishings, husbandry techniques, and enrichment practices impact the welfare of tokay geckos which will be crucial for refining our understanding of and improving on the welfare of reptiles in captivity.