Forecasting community dynamics: the mast system

Forecasting community dynamics: the mast system


PIs: Jim Clark, Jen Swenson, Roland Kays (NC Museum of Natural History, NCSU)

The impact of climate change on biological communities will depend on interactions involving the local habitat and the species that interact with one another—as each species responds directly to climate it indirectly affects all of the species with which it interacts. These species interactions complicate efforts to predict climate effects, because each species experiences habitat complexity at a different scale—from flightless insects to large vertebrates.  Current efforts focus on the effects of climate change, land cover, and soils, but do not benefit from estimates of food availability. This study will determine how tree fecundity varies with tree size and habitat, including masting cycles and aging.  It will evaluate how diverse communities of species monitored in NEON (ground beetles, vascular plants, small mammals, birds) respond together with food supply, in the form of masting shrubs and trees, and large mammal surveys. A focus on the mast system of pulsed seed and fruit production from trees, includes vertebrate consumers, and indirect interactions with arthropod competitors and vertebrate predators.  Our study aims to evaluate the contribution of mast (fruit and seed production by trees and shrubs) to consumer abundances, relative to other food sources.  Specifically, we deploy seed traps, evaluate individual tree attributes (include cone production for conifers), and camera traps, to quantify activity of large vertebrates.  Remotely-sensed imagery and the NEON airborne observatory will be used to characterize habitat diversity.

Results of this analysis will be used to evaluate community change and reorganization, including prediction and attribution of tree population response to climate change, climate risk by species and habitat and how it is shared across species groups. New data on large mammals and seed production from NEON sites will be made available to the community. The study will engage the public through citizen assisted identification of animal images.

Field sites are described here, together with those of collaborators on the synthesis of mast data.

Methods: Cone count methods are here.  Model fitting is here.

Results are being made available on a web site under development here.


Modeling framework

Clark, J.S., C. Nunes, and B. Tomasek. 2019. Foodwebs based on unreliable foundations: spatio-temporal masting merged with consumer movement, storage, and diet. Ecological Monographs, in press. Appendix