A global review on the role of small rodents and lagomorphs (clade Glires) in seed dispersal and plant establishment

Zoochory is an ecologically and evolutionarily important seed dispersal type. The decline and extinction of seed-dispersing large herbivores severely threatens dispersal-driven ecosystem processes in many regions. Hence the relative importance of small rodents and lagomorphs (Glires, Mammalia) as dispersal vectors might increase due to their ubiquity, diversity and abundance. Here we provide a review of rodent- and lagomorph-mediated seed dispersal based on approximately 600 papers found in an extensive literature search. We highlight that small rodents and lagomorphs disperse seeds via various mechanisms. The seldom documented epi- and endozoochory are probably universal in these groups. Due to their small home range, short fur and small body size, these mechanisms generally operate at small scales and mainly for small seeds. Taxon-specific feeding, nesting and behavioural characteristics provide a wide spectrum of other seed dispersal types, such as synzoochory (food caching). The studied taxa generally support seed dispersal within a particular habitat patch, contributing to the persistence of local populations, but in rare cases, long-distance dispersal events might occur. Besides seed dispersal, rodents and lagomorphs can also support plant establishment and provide safe sites for seeds where they can survive stochastic events. Studies reviewed here show a strong bias both in scope and geographical distribution: synzoochorous dispersal of woody plants is known in detail, and most studies were conducted in the same few countries and habitat types. In contrast, other mechanisms such as endozoochory, epizoochory and habitat types like grasslands and anthropogenic habitats have rarely been studied. We show examples on ecosystem services and disservices related to rodent- and lagomorph-mediated seed dispersal as well as the importance of these processes in habitat conservation and restoration.

Automated summary

Zoochory, the dispersion of seeds by animals, plays a crucial role in ecological and evolutionary processes. The decline of large seed-dispersing herbivores threatens this mechanism, increasing the importance of small rodents and lagomorphs in seed dispersal. These animals disperse seeds through various mechanisms such as epi- and endozoochory. While their actions generally occur at a small scale, they contribute to local population persistence and can occasionally facilitate long-distance dispersal events. Additionally, rodents and lagomorphs support plant establishment and provide safe sites for seeds. However, studies on seed dispersal by these animals have geographical and scope biases, with a focus on specific countries and habitat types.