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The sum of fruit and seed predation by multiple species may strongly affect plant reproduction and population dynamics. We evaluated the combined effects of ungulates, seed-eating rodents and insect pre-dispersal seed predators on the reproductive success of the Mediterranean gum cistus shrub (Cistus ladanifer), over two consecutive years within a long-term ungulate-exclusion experiment. We compared fruiting success in shrubs exposed and protected from ungulates by examining fruit abortion and fruit production. We also investigated the effect of insect predation on seed production (i.e. proportion of depredated fruit and seed loss) and measured fruit weight, seed number per fruit, and seed weight of unpredated fruits. Ungulate browsing directly removed 42.3% of the plant reproductive structures, early in the reproductive season and insect predation reduced mature seeds by over 40%. Results also emphasize the additive effects of ungulate browsing on pre-dispersal insect predation and fruit abortion which increased by 74.7% and 60.9%, respectively. Rodents, which only occurred in ungulate-excluded plots, had a limited and later effect on seed production with 6% of mature fruit loss. Fruit weight, seed weight and number were higher in shrubs protected from ungulates. Our study indicated that seed predation by mice was irrelevant, but ungulate and invertebrate seed predation interacted to strongly limit the reproductive success of C ladanifer, potentially affecting plant population dynamics in the long-term., We acknowledge the Portuguese Science Foundation (FCT) for research funding UID/AGR/00239/2013 and financial support to XL (SFRH/BD/90753/2012), MCC (IF/00740/2014), MNB (IF/01171/2014) and JMF (IF/00728/2013).

Quercus suber and Quercus ilex trees are major elements of Mediterranean landscapes, which are threa- tened by the increasing water deficits related to climate change. To contribute to the understanding of the capacity of these oaks to withstand severe drought we assessed the vulnerability to xylem embolism and the anatomical traits in current-year shoots. Data were collected in mature trees at two sites, in cen- tral/coastal and southern/inland Portugal. In situ safety margins to hydraulic failure were evaluated from long-term predawn and midday leaf water potential records. Results showed that xylem vulnerability to embolism was similar in Q. ilex and Q. suber. The 50% loss in hydraulic conductivity (Wxyl,50PLC) was observed at xylem water potentials of � 2.9 and � 3.2 MPa in shoots of Q. suber and Q. ilex, respectively. Values of mean vessel diameter of Q. suber shoots at both sites suggest an intra-species adaptation to the local water availability, with larger vessels at the more mesic site. In situ hydraulic safety margins observed in shoots showed that, even during the driest periods, both oaks lived comfortably above the most critical embolism thresholds. However, the hydraulic safety margins were narrower in the driest site. Results are relevant to the understanding of survival, growth, and functional behaviour of evergreen oaks in Mediterranean climates, under recurrent/seasonal drought conditions.