How does increasing mast seeding frequency affect population dynamics of seed consumers? Wild boar as a case study

Abstract

Mast seeding in temperate oak populations shapes the dynamics of seed consumers and numerous communities. Mast seeding responds positively to warm spring temperatures and is therefore expected to increase under global warming. We investigated the potential effects of changes in oak mast seeding on wild boar population dynamics, a widespread and abundant consumer species. Using long‐term monitoring data, we showed that abundant acorn production enhances the proportion of breeding females. With a body‐mass‐structured population model and a fixed hunting rate of 0.424, we showed that high acorn production over time would lead to an average wild boar population growth rate of 1.197 whereas non‐acorn production would lead to a stable population. Finally, using climate projections and a mechanistic model linking weather data to oak reproduction, we predicted that mast seeding frequency might increase over the next century, which would lead to increase in both wild boar population size and the magnitude of its temporal variation. Our study provides rare evidence that some species could greatly benefit from global warming thanks to higher food availability and therefore highlights the importance of investigating the cascading effects of changing weather conditions on the dynamics of wild animal populations to reliably assess the effects of climate change.

Climate warming causes mast seeding to break down by reducing sensitivity to weather cues

“…The changes in seed production will determine the capacity of trees to disperse seed to the novel habitats they may occupy in the future (Clark et al, 2021; Ibáñez et al, 2008; Zhu et al, 2012). Furthermore, changes in masting patterns have tremendous ecosystem consequences as masting acts as pacemaker for trophic interactions (Ostfeld & Keesing, 2000; Touzot et al, 2020). Understanding the mechanistic drivers of changes in seed production is therefore necessary to predict how ongoing climate change will influence future forest dynamics and their food webs.…”

Effects of pulsed resources on the dynamics of seed consumer populations: a comparative demographic study in wild boar

“…For all study areas, we analyzed CMRR data using a multistate model (see Lebreton et al 2009 for a review) that allows annual natural mortality (NM j , t ) to be estimated separately from annual hunting mortality (HM j,t ) for each body mass class j . The model has already been fully described in previous works (Gamelon et al 2012, Touzot et al 2020) but we provide here a brief overview of its structure.…”

Flowering synchrony drives reproductive success in a wind‐pollinated tree

“…Most of these studies focus on changes in the average or onset of phenological events, with less emphasis on changes in the length of flowering periods or changes in variation among individuals within populations (Zohner et al, 2018). Our results suggest that the nature of changes in flowering phenology can be a critical component to patterns of mast-seeding in trees, with subsequent cascading effects on consumer communities (Ostfeld and Keesing, 2000;Touzot et al 2020).…”