Tracking Bat‐Dispersed Seeds Using Fluorescent Pigment¹

Abstract

Tracking the dispersal of seeds by fruit‐eating animals in tropical rain forests is crucial to further our understanding of plant–frugivore interactions and their impacts upon forest regeneration and plant population dynamics. We tested the feasibility of tracking bat‐dispersed seeds in a Philippine lowland rain forest with the help of fluorescent pigment. The powder was mixed with acetone and sprayed to ripe fruits of fig trees, i.e., Ficus septica and F. variegata. During nightly monitoring using a hand‐held ultraviolet lamp bat deposits (seed‐containing spat outs and feces) could successfully be detected. Distances and directions of deposit sites to the focal trees were recorded and seed shadow areas were analyzed. Bats dispersed most of the seeds less than 50 m away from the parent plants resulting in seed shadow areas < 0.30 ha in size. An in situ fruit preference experiment showed that fluorescent powder is unlikely to deter bats from feeding on ripe figs. In conclusion, the technique is simple, inexpensive, noninvasive, applicable to different fields of research and allows one to follow the fate of seeds from known sources.

Acorn dispersal estimated by radio-tracking

“…For Xeshy-fruited endozoochorous species, a simple method based on applying a Xuorescent dye to the fruits and recovering it in faecal material has been successfully applied (Levey and Sargent 2000;Levey et al 2005;Reiter et al 2006). For plants with large seeds that are dispersed by scatter-hoarding animals (e.g.…”

Defensive fruit metabolites obstruct seed dispersal by altering bat behavior and physiology at multiple temporal scales

“…However, the spatial consequence of fruit secondary compounds remains largely overlooked because seeds are difficult to track individually (Nathan and Muller-Landau 2000). Despite innovations in direct (Forget and Milleron 1991, Reiter et al 2006, Hirsch et al 2012) and indirect seed tracking methods (Godoy and Jordano 2001, Jordano et al 2007, Carlo et al 2009), it is often prohibitively burdensome to assess post-removal seed fates. One tractable way to assess seed dispersal quality in terms of dispersal distance is to use frugivore movement data paired with ecologically relevant information on fruit preferences and seed passage/ handling times (e.g., Westcott et al 2005, Kays et al 2011, Karubian et al 2012, Abedi-Lartey et al 2016, Rehm et al 2019, van Toor et al 2019.…”

Directed seed dispersal of Piper by Carollia perspicillata and its effect on understory plant diversity and folivory

“…In lowland forests, these feeding roosts are in mostly medium to large cavities in tree trunks to which C. perspicillata shows roost fidelity (Lewis 1995). Frugivorous bats have been found to be effective seed dispersers, which may defecate in flight or often shortly before engaging in flight, presumably to reduce body mass (Gorchov et al 1993, Corlett 1998, Reiter et al 2006, Muscarella and Fleming 2007. These behavioral traits increase the likelihood of seeds being dispersed near roosts, resulting in a Piper seed shadow associated with the roosts.…”