Masting increases seedling recruitment near and far: Predator satiation and improved dispersal in a fleshy‐fruited tree

Abstract

The animal dispersal hypothesis predicts that mast seeding can increase dispersal rate of seeds by dispersers and enhance reproductive success of plants. However, in contrast to pollination efficiency and predator satiation hypothesis, the animal dispersal hypothesis has received mixed support. Using 12‐year data on fruit production and seedling recruitment of a fleshy‐fruited tree rowan (Sorbus aucuparia, Rosaceae), we tested if an increase in the fruit production at the population level results in higher proportion of fruits recruiting into seedlings. Recruitment was recorded near (under rowans) and far (under heterospecifics) from conspecifics. Higher recruitment rates under rowans would support predator satiation hypothesis. Higher recruitment rates under heterospecific trees, where fruits can only arrive with animal assistance, would support animal dispersal hypothesis. High population‐level fruit production increased the proportion of fruits recruiting into seedlings both near and far from rowans. In contrast, high individual‐level fruit production did not have a positive effect on the proportion of fruits recruiting into seedlings. Synthesis. Population‐level synchronisation of fruit production is required to generate a more effective plant regeneration. Our findings show that masting enhances seedling recruitment through predator satiation and increased seed dispersal by frugivores. The results provide support for both animal dispersal and predator satiation hypotheses indicating that both mechanisms can operate simultaneously.

Grazing hinders seed dispersal during crop failure in a declining oak woodland

“…Our inter-tree seed dispersal comparison is compatible with few studies documenting shorter dispersal differences with increased seed abundance (Jansen et al, 2004;Moore et al, 2007). As the success year had simultaneously twice the rodent density and far fewer dispersal events, our results also countered the so-called predator dispersal hypothesis (Vander Wall & Balda, 1977;Vander Wall, 2010), predicting that larger crops may imply higher per capita seed dispersal rates or longer dispersal distances than in nonmasting years (Seget et al, 2022). Our data better support the predator satiation hypothesis as mechanism of mast seeding in cork oak woodlands.…”

Relatives reproduce in synchrony: kinship and individual condition shape intraspecific variation in masting phenotype

“…Rowan is the host of larvae of the apple fruit moth Argyresthia conjugella, which causes substantial seed loss [43,44]. Masting in rowan helps to reduce fierce seed predation by insects from 70-80% to 10-30% [44,45], and increases dispersal rates by frugivores [46]. The proportion of fruits successfully established as seedlings increases with population-level fruit production, through enhanced reproductive efficiency ensured by economies of scale [44].…”

The ecology, evolution and management of mast reproduction in Australian plants

“…Adaptive drivers behind masting generally invoke 'economies of scale', whereby the reproductive output of individuals in concert with the scale of the population generates an evolutionary advantage for the individual. Such evolutionary advantages include satiation of seed predators (Janzen 1971;Tsvuura et al 2011;Borchert and DeFalco 2016;Boggess et al 2021;Zwolak et al 2022), increased pollination efficiency in wind-and animal-pollinated species (Waller 1979;Kon et al 2005;Crone and Lesica 2006;Schermer et al 2019;Bogdziewicz et al 2020a), increased seed dispersal by scatter-hoarding animals (Zwolakl et al 2016;Wang et al 2021;Seget et al 2022) and other proposed responses (Pearse et al 2016;Pesendorfer et al 2021). There may also be genetic controls behind high plant reproductive CVp (i.e.…”