Main interactions found for the proportion of seeds (full samaras) predated on the ground.

<p>a) Relationship between microhabitat of samara deposition and guild of foragers; b) Relationship between natural samara availability and proportion of empty samaras. 0% empty samaras means that all samaras were full.</p

Summary of the Wald χ²-test for the GLMM to analyze the factors affecting seed predation (proportion of full samaras predated in each depot).

<p>Microhabitat (M) refers to open vs. shrub cover; foragers (F) refers to depot type (exclosures) for different guild of seed foragers; samara quality (Q) is the proportion of empty samaras in the depot and samara availability (A) is the natural availability of samaras in the study area. Data for the best-fitting model (ΔAIC = 0); AIC = 282.4; Akaike weight = 0.69; Residual deviance = 258.4. Confidence intervals for the parameter estimates of this model and the randomized models are shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0065573#pone.0065573.s001" target="_blank">Table S1</a> (bootstrapping).</p

Proportion of seeds (full samaras) predated on the ground.

<p>Proportions are shown in relation to microhabitat of deposition, guild of foragers, proportion of empty samaras in the depot and natural samara availability.</p

<i>Ulmus laevis</i> samara characterization.

<p>Pictures of the different samara categories are shown on the top row and sketches on the bottom row: (A) full samara (FS); (B) undeveloped samara (US); (C) empty samara (ES); (D and E) predated samaras (PS). The black colour of the sketch stands out the seed for FS and US, and the tissues torn by animals in the PS.</p

Density estimation of the main avian elm seed predators for two consecutive springs.

<p>Significant (<i>P</i><0.05) and marginally significant differences (<i>P</i><0.10) between years for each species are indicated by (*) and (†), respectively.</p

Samara production.

<p>a) Fruit crop size for each samara category and season; b) proportion of empty samaras dispersed throughout each season; c) proportion of each samara category dispersed along the mast year 2010.</p

Empty Seeds Are Not Always Bad: Simultaneous Effect of Seed Emptiness and Masting on Animal Seed Predation

<div><p>Seed masting and production of empty seeds have often been considered independently as different strategies to reduce seed predation by animals. Here, we integrate both phenomena within the whole assemblage of seed predators (both pre and post-dispersal) and in two contrasting microsites (open vs. sheltered) to improve our understanding of the factors controlling seed predation in a wind-dispersed tree (<i>Ulmus laevis</i>). In years with larger crop sizes more avian seed predators were attracted with an increase in the proportion of full seeds predated on the ground. However, for abundant crops, the presence of empty seeds decreased the proportion of full seeds predated. Empty seeds remained for a very long period in the tree, making location of full seeds more difficult for pre-dispersal predators and expanding the overall seed drop period at a very low cost (in dry biomass and allocation of C, N and P). Parthenocarpy (non-fertilized seeds) was the main cause of seed emptiness whereas seed abortion was produced in low quantity. These aborted seeds fell prematurely and, thus, could not work as deceptive seeds. A proportion of 50% empty seeds significantly reduced ground seed predation by 26%. However, a high rate of parthenocarpy (beyond 50% empty seeds) did not significantly reduce seed predation in comparison to 50% empty seeds. We also found a high variability and unpredictability in the production of empty seeds, both at tree and population level, making predator deception more effective. Open areas were especially important to facilitate seed survival since rodents (the main post-dispersal predators) consumed seeds mostly under shrub cover. In elm trees parthenocarpy is a common event that might work as an adaptive strategy to reduce seed predation. Masting <i>per se</i> did not apparently reduce the overall proportion of seeds predated in this wind-dispersed tree, but kept great numbers of seeds unconsumed.</p></div

HDY-12_ORO379_nSSR_data

Genetic data and spatial coordinates from nine field populations of Ulmus minor Mill. located in Majorca and Minorca Islands (Balearics), Baetic mountains in SE Iberia and Catalonia in NE Iberia. DNA extracted from fresh tissue was amplified by nine microsatellite loci, six of them specifically developed for Ulmus minor (Ulmi1-11, Ulmi1-21, Ulmi1-98, Ulmi1-165, Ulmi2-16 and Ulmi2-20 (Collada et al., 2004)) and three developed for U. laevis (Ulm2, Ulm3 and Ulm8 (Whiteley et al 2003)). A Li-Cor 4300 sequencer (Li-Cor Biosciences, Lincoln, USA) was used to obtain banding profiles. Allele sizes given in base pairs were determined using the SequamarkTM molecular size standard (Invitrogen, Carlsbad, USA) and the software Gene ImagIR 3.56 (Scanalytics)

Perea_2015_Oikos_Seed_Recovery_rodents

Raw data on the recovery of seeds (acorns of Quercus pyrenaica) by rodents (Apodemus sylvaticus) after having been dispersed by the same rodent specie

Dryad_HDY-13-OR0304R_Survival_Growth_Data

Dryad_HDY-13-OR0304R_Survival_Growth_Dat