Preliminary diet record of hinge-back tortoise Kinixys zombensis: a potential seed disperser?

Abstract

Seed dispersal by chelonians (i.e. tortoises, turtles and terrapins) is geographically and taxonomically widespread, more so than any other reptilian groups (Falcón et al., 2020). Frugivorous chelonians are generally considered efficient seed dispersers, meaning that dispersal events facilitated by chelonians often result in the successful establishment of fertile plant recruits (i.e. the seed dispersal effectiveness framework; Schupp et al., 2010). Chelonians can consume large quantities of diverse fruit species, cause little damage to seed viability when consuming and digesting fruit, and transport seeds relatively great distances through long gut-retention times (Blake et al., 2012; Falcón et al., 2020). Thus, frugivorous chelonians can play an important role in maintaining ecosystem structure and functionality, so much so that giant tortoises are reintroduced onto islands to initiate the restoration of ecosystem processes (Falcón & Hansen, 2018). Chelonian frugivory and seed dispersal, however, are generally understudied with most case studies originating from Amazonian rainforests, North American deserts and tropical islands (Falcón et al., 2020). Yet, the seed dispersal effectiveness of chelonians in continental Africa has rarely been assessed (e.g. Milton, 1992; Setlalekgomo & Sesinyi, 2014).