Agouti reintroduction recovers seed dispersal of a large‐seeded tropical tree

Abstract

The aim of animal reintroductions has mainly been species recovery; only few reintroduction initiatives focus on ecosystem restoration. Therefore, reintroduction consequences on ecological interactions are seldom assessed. We used the interaction between a reintroduced population of agoutis (Dasyprocta leporina) and a vulnerable tropical endemic tree (Joannesia princeps) to examine reintroduction effects on seed dispersal and seedling establishment. To test the outcomes of this interaction, we tracked seeds of J. princeps in two adjacent forest areas with and without reintroduced agoutis. We also assessed if dispersal distances affected seedling survival. To determine seed fate and dispersal distance, we used spool‐and‐line tracking, together with camera traps to identify dispersers. Agoutis were the only species removing J. princeps seeds, thus dispersal only occurred where agoutis had been reintroduced; in the area without agoutis, all seeds remained intact on the soil, even one year after the experiment's beginning. At the reintroduction area, most seeds were preyed upon by agoutis but 7% remained dispersed and 2% germinated after ten months. Only seeds buried by agoutis were able to germinate. Most dispersed seeds were dispersed 15 m or farther and longer dispersal distances benefited J. princeps, since seedlings farther from a conspecific adult tree had greater survival probability. Agoutis were also seen burying seeds of two other plant species; these mammals have the potential to benefit dozens of large‐seeded species in our study system. Agouti reintroduction thus exemplifies the value of trophic rewilding programs to re‐establish ecological interactions and restore ecosystem functioning.Abstract in Portuguese is available with online material

A framework to assess the effects of changes in species composition on processes derived from trophic interactions

“…Our results show they are highly original and disperse larger seeds that have fewer dispersers in the Park. A recent study has identified that one of the largest seeds in TNP ( Joanesia princeps ) only germinated when buried by agoutis (Mittelman et al 2020). Moreover, due to their scatter-hoader behaviour, agoutis are able to disperse large seeds over great distances (Jansen et al 2012).…”

Functional robustness of seed dispersal by a remnant frugivore population on a defaunated tropical island

“…"Functional rescue" implies that an ecological process has been lost through local extinction, but that it can be recovered through species reintroduction or ecological replacement. For example, translocated populations of frugivores such as tortoises (Griffiths et al, 2011) and agouti (Mittelman et al, 2020) have reversed the suppressed recruitment of rare tree species in their respective habitats. In defaunated ecosystems, ecological functions such as seed dispersal may be dependent on remnant animal populations.…”

Postweaning Performance of the Agouti (Dasyprocta leporina): A Neotropical Rodent with Potential for Domestication

“…This rodent has been identified as a selective group of animal that has the potential to be domesticated [ 3 ], and some authors have also grouped them as mini-livestock [ 4 ]. This rodent is essential as a seed disperser and plays a crucial role in reforestation [ 5 ]. This rodent also has a wide range of habitats from savannahs to rainforests [ 6 , 7 ].…”