Seed predation and potential dispersal of Ceratocaryum argenteum (Restionaceae) nuts by the striped mouse (Rhabdomys pumilio) / Joseph Douglas Mandla White

This study aimed to better understand the role of rodents as seed predators and dispersers in the fynbos biome at De Hoop Nature Reserve, South Africa in May and June, 2013. Based on previous studies I hypothesised that the large, nut-like seeds of Ceratocaryum argenteum (Restionaceae) are scatter-hoarded by rodents and that rodent seed choices and seed fates are affected by seed size and hull thickness. Field trials using three seed types showed that smaller seeds with a high reward and low processing cost were consumed significantly(p<0.01) more than large, thick hulled seeds. Application of wire tags to facilitate discovery of relocated seeds had no significant influence on seed choice (p>0.05), but further research should be conducted to determine if spooling of C. argenteum seeds influences rodent seed choice. Smaller seeds with a high-reward and low processing cost showed a significantly greater percentage of usage (p<0.01) where seed stations were encountered and exploited. Rhabdomys pumilio was confirmed as being the most common murid at the study site, however, it seems unlikely that it scatter-hoards C. argenteum seeds, as no consumption or burial of seeds was observed. However, R. pumilio did show an interest in C. argenteum seeds and attempted to consume some seeds or carried seeds over distances not significantly different (p>0.05) from the observed distances between nearest neighbour C.argenteum plants before discarding them on the soil. Additionally, the maximum distance R. pumilio moved C. argenteum seeds was commensurate with the maximum distance between nearest neighbour C. argenteum stands, so the end fate of the seeds remains unknown. Further research should account for seasonal variability in scatter-hoarding behaviour.

Grantor dc:publisher.institution

Department of Biological Sciences

Year dc:date.issued

2013

Author dc:creator

• White, Joseph Douglas Mandla

Advisors dc:contributor.advisor

• Bronner, Gary N
• Midgley Jeremy J

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/14027

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/14027