Neighborhood effects on seed dispersal by frugivores: testing theory with a mistletoe–marsupial system in Patagonia

Morales, Juan Manuel; Rivarola, Maria Daniela; Amico, Guillermo C.; Carlo, Tomás A.

doi:10.1890/11-0935.1

Cited by 72 publications

(64 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In neighborhoods with many fruiting species, crop size is an important variable for predicting fruit removal-the larger the crop size the higher the fruit removal (Morales et al, 2012). There are two primary hypotheses to explain how crop size and the spatial aggregation of fruiting plants may influence fruit removal by vertebrates: the competition hypothesis and the facilitation hypothesis (Sargent, 1990).…”

Section: Neighborhood Effectsmentioning

confidence: 99%

Connecting Resource Tracking by Frugivores to Temporal Variation in Seed Dispersal Networks

2017

View full text Add to dashboard Cite

Mutualistic interactions between species are crucial for the maintenance and functioning of the community. Current research has shown the importance of not only understanding the structure of these mutualistic interaction networks but also their temporal dynamics. Temporal changes in species abundance, such as those caused by vertebrate resource tracking, may create temporal variability in a network though neighborhood effects and influence the directedness of dispersal. While much research has been done on resource tracking, neighborhood effects, and directed dispersal individually, little research has been done into their interrelationships and, therefore, theory of how resource tracking can influence frugivory and seed dispersal networks remains poorly developed. We use the available literature to show the prevalence of resource tracking by vertebrate frugivores and hypothesize how, through neighborhood effects, resource tracking may influence short-term variation in network properties. We then discuss how resource tracking can influence long-term network properties by altering the dispersal of plant species. Lastly, we use this information to hypothesize how the introductions of new species into a community may alter the influence of resource tracking on frugivory and seed dispersal. While trait matching and links that are not possible between species in a community (i.e., forbidden links) play a large role in determining the structure of a network, temporal change in the abundance of species due to resource tracking may also affect the properties of networks. By increasing our understanding of the role resource tracking has in the temporal variability of frugivory and seed dispersal networks, we can better determine the full extent of species interactions and provide valuable information for the conservation of ecological communities.

show abstract

Section: Neighborhood Effectsmentioning

confidence: 99%

Connecting Resource Tracking by Frugivores to Temporal Variation in Seed Dispersal Networks

2017

View full text Add to dashboard Cite

show abstract

“…For example, frugivorous birds are commonly shown to use cover-rich neighbourhoods (e.g. Morales et al 2012) and therefore more seeds are expected to be dispersed under forest patches compared to open areas (Herrera and García 2010). However, despite many insights having been gained to date, knowledge of how landscape structure influences frugivore-mediated seed dispersal patterns in heterogeneous landscapes-particularly those generated by frugivore guilds other than birds-, is still limited (Herrera and Doblas-Miranda 2013).…”

Section: Introductionmentioning

confidence: 99%

Landscape structure shapes carnivore-mediated seed dispersal kernels

2015

View full text Add to dashboard Cite

Context Seed dispersal is recognized as having profound effects on the distribution, dynamics and structure of plant populations and communities. However, knowledge of how landscape structure shapes carnivore-mediated seed dispersal patterns is still scarce, thereby limiting our understanding of large-scale plant population processes. Objectives We aim to determine how the amount and spatial configuration of forest cover impacted the relative abundance of carnivorous mammals, and how these effects cascaded through the seed dispersal kernels they generated. Methods Camera traps activated by animal movement were used for carnivore sampling. Colour-coded seed mimics embedded in common figs were used to know the exact origin of the dispersed seed mimics later found in carnivore scats. We applied this procedure in two sites differing in landscape structure. Results We did not find between-site differences in the relative abundance of the principal carnivore species contributing to seed dispersal patterns, Martes foina. Mean dispersal distance and the probability of long dispersal events were higher in the site with spatially continuous and abundant forest cover, compared to the site with spatially aggregated and scarcer forest cover. Seed deposition closely matched the spatial patterning of forest cover in both study sites, suggesting behaviour-based mechanisms underpinning seed dispersal patterns generated by individual frugivore species. Conclusions Our results provide the first empirical evidence of the impact of landscape structure on carnivore-mediated seed dispersal kernels. They also indicate that seed dispersal kernels generated strongly depend on the effect that landscape structure exerts on carnivore populations, particularly on habitat-use preferences.Electronic supplementary material The online version of this article

show abstract

“…Stable isotope ratios can also be used to estimate the proportion of a 'batch' of dispersed seeds (e.g. in a seed trap or fecal clump) that originated from a labeled source plant or patch, as Morales et al (2012) demonstrated in their study of mistletoe dispersal, by grinding seeds together and analyzing the isotopic signal with a Bayesian mixing model. …”

Section: Resultsmentioning

confidence: 99%

Using a Stable Isotope to Label Seeds and Seedlings of an Invasive Shrub, Lonicera maackii

Castellano

Gorchov

2013

Invasive plant sci. manag.

View full text Add to dashboard Cite

Seed dispersal is a crucial process in most plant invasions, but is notoriously difficult to study. One technique to identify the maternal source of dispersed seeds and newly established seedlings is labeling with a stable isotope. We tested whether foliar application of 15N-labeled urea would result in sufficient 15N enrichment to discriminate among seeds and seedlings grown from those seeds of the invasive shrub Lonicera maackii (Amur honeysuckle). We subjected mature L. maackii to all combinations of three concentrations of 15N-labeled urea (0.025 g L−1 [0.003 oz gal−1], 0.20 g L−1, and a 0 g L−1 control) and three temporal treatments (one application in August, one application in September, and five applications spaced every three weeks from June through August). Seeds were collected September to November; some of these were analyzed for %15N and others allowed to germinate and grow into seedlings under two treatments (in potting mix in greenhouse and in woodlot soil outdoors). Seedlings were harvested midway through the next growing season. We found that seeds from plants subjected to the three different concentrations had significantly different %15N levels, and there was a significant interaction between concentration and temporal treatment: the highest seed %15N levels were from plants sprayed five times with 15N-labeled urea, and the second highest from plants sprayed once in September. Similar patterns in %15N levels were found in seedlings, except that those from the 0.025 g L−1 spray treatment were only distinguishable from controls for seedlings grown outdoors in woodlot soil. These findings demonstrate that a single foliar application of 15N in early September is sufficient to label both seeds and seedlings of this invasive shrub, enabling one to identify the source of field-collected seeds or seedlings. This provides a tool for studying patterns and processes in seed dispersal of Amur honeysuckle and potentially other invasive plants.

show abstract

Neighborhood effects on seed dispersal by frugivores: testing theory with a mistletoe–marsupial system in Patagonia

Cited by 72 publications

References 45 publications

Connecting Resource Tracking by Frugivores to Temporal Variation in Seed Dispersal Networks

Connecting Resource Tracking by Frugivores to Temporal Variation in Seed Dispersal Networks

Landscape structure shapes carnivore-mediated seed dispersal kernels

Using a Stable Isotope to Label Seeds and Seedlings of an Invasive Shrub, Lonicera maackii

Contact Info

Product

Resources

About