Published research

Zombie seeds

Many seed-eating mammals and birds survive yearly periods of food scarcity by hoarding seed reserves. We carried out a series of experiments to understand why Red acouchies (Myoprocta exilis) hoard Carapa procera (Meliaceae) seeds that lack dormancy and germinate rapidly, hence seem unsuitable for long-term storage. We found that acouchies manipulated the seeds to slow down germination, and caused the seeds to become “zombie seeds”; alive, but unable to re-sprout.

 With Frans Bongers and Herbert Prins ( Wageningen University )

MSc student: Martijn Bartholomeus

Published in Oikos in 2006 

Hunting and dispersal limitation

Many trees depend on scatter-hoarding rodents for seed dispersal. Seeds not removed from below the parent plant usually die due to insects, fungi, or desiccation.

We studied whether hunting, by limiting disperser activity, increased dispersal failure in Carapa procera, a non-timber forest product, in Surinam and French Guiana . In each of four populations in French Guiana and Surinam , two with poaching and two without, we compared rates of seed removal for individual trees varying in crop size in years of high and low population-level seed abundance.

With Pierre-Michel Forget (Museum National d’Histore Naturelle).

Published in Conservation Biology in 2006

Seed size, seed abundance, and seed dispersal by scatter-hoarding rodents
Tree species that rely on scatter-hoarding animals for seed dispersal tend to have large seeds and mast seeding. We used video monitoring and seed tracking techniques to compare the fate of Carapa procera seeds with different sizes in years of contrasting seed abundance in French Guiana , and found that both seed size and seed abundance enhance the dispersal effectiveness of scatter-hoarding rodents. This work is the core of my PhD.

With Frans Bongers, Herbert Prins, Sip van Wieren, Jan den Ouden, and Lia Hemerik ( Wageningen University ).

MSc students: Almira Siepel, Marion Diemel, Sander Coenraadt, Anne Rutten, Martijn Bartholomeus, Jelmer Elzinga 

Published in Seed Dispersal and Frugivory: Ecology, Evolution and Conservation in 2002

Published as a dissertation in 2003 

Published in Ecological Monographs in 2004