Abstract
AbstractEscaping seed predation is a classic “economy of scale” hypotheses (predator satiation hypothesis, Psh) to explain the selection for the synchronous production of massive and nil seed crops (masting) in plants. The Psh postulates that predator satiation occurs through a combination of (1) “functional satiation,” as not all seeds can be consumed during a massive crop, and (2) “numerical satiation,” as predator populations collapse during poor crop years. Many studies advocate for the Psh, but few have investigated the importance of masting compared to other factors for the control of predation extent. Namely, environmental cues prompting masting could also determine predator's success and, ultimately, influence directly and independently seed predation intensity. We explored this question in Mediterranean oaks, as they exhibit strong masting behavior; acorns are heavily predated upon by weevils; and rainfall stochasticity drives masting and the emergence of adult weevils from the soil. Results of two mid‐term studies (4 and 11 yr) showed that acorn production and predation were highly variable across years, while the abundance of adult weevils was positively related to autumn rainfall and to the number of infested acorns the previous years. Ultimately, acorn predation was negatively influenced by inter‐annual fluctuation of seed production (masting) yet, mainly and positively, prompted by autumn rainfall and acorn crop size (only in one site). Our results highlight the relevance of masting to reduce seed predation. Yet evidences that rainfall stochasticity directly determines the success of weevils, and it independently influences seed predation extent, indicate that environmental cues prompting masting may also fine‐tune the output of this reproductive behavior. Additionally, local differences suggest that the relevance of masting may change with tree characteristics (low vs. high seed production) and landscape structure (isolated vs. dense forests). We also discuss what can be the effects of increasing drought in Mediterranean areas for this antagonistic interaction, triggered by rainfall.
Highlights
The synchronous and intermittent production of large and nil seed crops is a taxonomically and geographically widespread reproductive behavior among plants (Kelly and Sork 2002)
As proposed by Satake et al (2004), the synchronous, irregular production of large and nil seed crops would lead to predator satiation by combining two different mechanisms: (1) “functional satiation” and (2) “numerical satiation”
Our results demonstrate that early autumn rainfall stochasticity directly affects the emergence of adult weevils from the soil, and this
Summary
The synchronous and intermittent production of large and nil seed crops (often termed masting) is a taxonomically and geographically widespread reproductive behavior among plants (Kelly and Sork 2002). Evolutionary hypotheses for the advantages of masting as a reproductive strategy are based on an “economy of scale” principle: A single but extraordinary reproductive episode should be more beneficial than continuous but moderate reproductive events (Kelly and Sork 2002). Masting is expected to be especially effective in controlling predators with specialized seed-feeding habits, limited mobility, and a short life span encompassed within the seeding season (Shibata et al 1998). This is the case of many preeminent seed consumers such as granivorous insects (e.g., weevils in Mulder et al 2012, Mun~oz et al 2014, bruchids in Peguero et al 2014)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
