Out of one shadow and into another: causes and consequences of spatially contagious seed dispersal by frugivores.

Kwit, Charles; Levey, D. J.; Turner, Sasha; Clark, Connie J.; Poulsen, John R.; Dennis, Andrew; Schupp, Eugene W.; Green, R. J.; Westcott, David A.

doi:10.1079/9781845931650.0427

Cited by 15 publications

(33 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This seed deposition pattern may result in seed limitation due to the disproportionate death of clumped seeds caused by competition and pathogens (Kwit et al 2007). If this occurs then lek areas of M. manacus, more specifically their displaying courts, may represent ecological traps for seeds, especially for seeds coming from plants located in the vicinity of lek areas for which M. manacus has been shown to be the main seed remover (Cestari & Pizo 2013).…”

Section: Discussionmentioning

confidence: 99%

Seed dispersal by the lek-forming white-bearded manakin (Manacus manacus, Pipridae) in the Brazilian Atlantic forest

Cestári

Pizo

2013

J. Trop. Ecol.

View full text Add to dashboard Cite

Abstract:The movement patterns of males, females and juveniles of lekking species often differ due to differences in the commitment to lek activities, which may lead to differences in the spatial distribution and dispersal distances of seeds they eat. By sampling seeds in three lek and non-lek areas of the white-bearded manakin (Manacus manacus), we tested whether this lekking species increased the abundance and species richness of seeds in lek areas and, at a finer scale, in 21 displaying courts within lek areas. Combining data on seed defecation or regurgitation rates by free-ranging individuals, the number of seeds in droppings or regurgitations of mist-netted birds, and the distances travelled by birds equipped with radio-transmitters, we estimated the potential spatial distribution of seeds generated by six resident males and six females or juveniles during the morning peak of lek activity and when lek activity decreased in the afternoon. There was no difference in the species richness (46 and 44 morphospecies, respectively) and abundance of seeds (15.4 ± 7.3 seeds and 14.0 ± 1.1 seeds, respectively) between lek and non-lek areas. Within leks both parameters increased in courts (45 spp., 17.6 ± 14 seeds) compared with non-court sites (22 spp., 1.9 ± 1.8 seeds), likely as a consequence of the longer time spent by resident males in perches in or near display courts. Distances moved by juveniles and females per 60-min period (183 ± 272 m) were greater than resident males (42.6 ± 22.0 m) in the mornings, while the opposite happened in the afternoons (55.2 ± 40.7 m and 157 ± 105 m, respectively). We conclude that the spatial aggregation of seeds in lek areas of M. manacus occurs at the court level, and the spatial distribution of deposited seeds varies with manakin lekking status and the daily period of foraging.

show abstract

Section: Discussionmentioning

confidence: 99%

Seed dispersal by the lek-forming white-bearded manakin (Manacus manacus, Pipridae) in the Brazilian Atlantic forest

Cestári

Pizo

2013

J. Trop. Ecol.

View full text Add to dashboard Cite

show abstract

“…We revealed for the first time how contagious seed dispersal in complex seed-disperser networks can arise by means of complementary proximate mechanisms acting synergistically at a range of spatial scales, and we provided a robust approach that can be applied widely to many other seed-dispersal systems (for reviews, see Schupp et al 2002, Kwit et al 2007). For instance, mapped multispecific seed rains generated by rodents (e.g., Beck and Vander Wall 2010), ants (e.g., Fedriani et al 2004), and diverse diplochorous systems (sensu Vander Wall and Longland 2004) are likely to benefit from our approach.…”

Section: Discussionmentioning

confidence: 99%

“…For example, whereas seeds of Pyrus-Chamaerops and Juniperus-Rubus were positively associated at small spatial scales (i.e., 10 m), seeds of Pyrus-Pistacia and Chamaerops-Pistacia were positively associated at larger scales (i.e., ;400 m). These positive associations may be related to different ultimate causes, such as selection by individual frugivores of complementary fruit species (Whelan et al 1998), or the formation through the dispersal season of multispecific seed aggregates (Kwit et al 2004(Kwit et al , 2007J. M. Fedriani and T. Wiegand, unpublished data).…”

Section: Discussionmentioning

confidence: 99%

Hierarchical mechanisms of spatially contagious seed dispersal in complex seed‐disperser networks

Fedriani¹,

Wiegand²

2014

Ecology

View full text Add to dashboard Cite

Abstract. Intra-and interspecific spatially contagious seed dispersal has far-reaching implications for plant recruitment, distribution, and community assemblage. However, logistical and analytical limitations have curtailed our understanding concerning the mechanisms and resulting spatial patterns of contagious seed dispersal in most systems and, especially, in complex seed-disperser networks. We investigated mechanisms of seed aggregation using techniques of spatial point pattern analysis and extensive data sets on mutispecific endozoochorous seed rain generated by five frugivorous mammals in three Mediterranean shrublands over two seasons. Our novel analytical approach revealed three hierarchical and complementary mechanisms of seed aggregation acting at different levels (fecal samples, seeds, pairs of seed species) and spatial scales. First, the three local guilds of frugivores tended to deliver their feces highly aggregated at small and intermediate spatial scales, and the overall pattern of fecal delivery could be described well by a nested doublecluster Thomas process. Second, once the strong observed fecal aggregation was accounted for, the distribution of mammal feces containing seeds was clustered within the pattern of all feces (i.e., with and without seeds), and the density of fecal samples containing seeds was higher than expected around other feces containing seeds in two out of the three studied seeddisperser networks. Finally, at a finer level, mark correlation analyses revealed that for some plant species pairs, the number of dispersed seeds was positively associated either at small or large spatial scales. Despite the relatively invariant patterning of nested double-clustering, some attributes of endozoochorous seed rain (e.g., intensity, scales of aggregation) were variable among study sites due to changes in the ecological context in which seeds and their dispersers interact. Our investigation disentangles for the first time the hierarchy of synergic mechanisms of spatially contagious seed dispersal at a range of spatial scales in complex seeddisperser networks, thus providing a robust and widely applicable framework for future studies.

show abstract

“…Holly seeds best illustrate this phenomenon, with 86% of detected dispersal events being toward sites with other fruiting Ilex, despite the fact that only 66.9% of all the FF stations were placed under fruiting holly (29.3% were under hawthorn, and the remainder 3.8% under Taxus baccata and Hedera helix). This may appear as ''movement without movement'' as dispersed seeds tend to arrive at similar sites to those they left behind (Kwit et al 2007). Thus, directional dispersal appears to be an important mechanism limiting the dissemination of seeds (sensu Schupp et al 2002), with the less obvious consequence of promoting the formation of plant neighborhoods with higher genetic diversity than otherwise would be expected (see Karubian et al 2010).…”

Section: Discussionmentioning

confidence: 99%

“…Our rationale is that fleshy-fruited habitats strongly attract seed dispersers coming from near or far. Thus, in variegated and fragmented landscapes, LDDs should be more likely to be directed to patches with fruit resources, by ''spatially contagious'' processes among plants bearing fruit (Kwit et al 2007). …”

Section: Introductionmentioning

confidence: 99%

Where do seeds go when they go far? Distance and directionality of avian seed dispersal in heterogeneous landscapes

Carlo

García

Martínez

et al. 2013

Ecology

120

112

View full text Add to dashboard Cite

Abstract. Seed dispersal at large scales strongly influences plant population dynamics. Still, ecologists have rarely measured seed dispersal at relevant scales, and the role of habitat types in affecting seed dispersal at long distances remains unexplored. We studied seed dispersal of Ilex aquifolium and Crataegus monogyna in northern Spain, hypothesizing that seeds would be recovered at higher rates and at longer distances (LDD) at habitats with fleshyfruited trees, compared to habitats with other tree types or at open habitats. We tracked seeds in eight landscapes by enriching trees with 15 N isotopes at the center of landscapes, and then detected 15 N-marked seeds by sampling at distances of up to 700 m. We found that seeds arrive in greater densities and at longer distances in habitats with trees, particularly fleshyfruited types, producing different LDD probabilities for each habitat. Results also show a disproportional arrival of seeds in habitats similar to those of mother plants, which should affect seed establishment and the genetic diversity of plant neighborhoods. Findings reveal the strong dependence of seed dispersal on the existing templates that guide the movements of avian dispersers in heterogeneous landscapes and also suggest that LDD above tree lines and beyond hard habitat edges can be difficult.

show abstract

Out of one shadow and into another: causes and consequences of spatially contagious seed dispersal by frugivores.

Cited by 15 publications

References 0 publications

Seed dispersal by the lek-forming white-bearded manakin (Manacus manacus, Pipridae) in the Brazilian Atlantic forest

Seed dispersal by the lek-forming white-bearded manakin (Manacus manacus, Pipridae) in the Brazilian Atlantic forest

Hierarchical mechanisms of spatially contagious seed dispersal in complex seed‐disperser networks

Where do seeds go when they go far? Distance and directionality of avian seed dispersal in heterogeneous landscapes

Contact Info

Product

Resources

About