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 our ability 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 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. 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 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 Notes from NEON sites
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. This collaboration includes Jen Swenson at Duke University and Roland Kays at NCSU and the Museum of Natural History.
At the time of this project, NEON sites are just beginning to host visits from individual PIs. Each site has its own ownership, permitting system, and management plan. For example, Florida sites include active fire management, which affects any sampling equipment left in the field. Permits and sampling are negotiated with each site individually. The time required to obtain permits varies site-to-site. These metadata notes summarize some of these issues for sites we sampled to be used by us, but perhaps by others.
15-16 June 2018
Jim Clark, Jordan Luongo
Sampling at the DSNY NEON site was facilitated by Guy Fausnaught at NEON and Beatriz Pace-Aldana, the Research Coordinator, plant and GIS specialist here. From 15-16 June we installed seed traps and collected data on cone production at three NEON plots: 6, 8, 10. Tree cover on other plots was too sparse to warrant seed production.
Formerly ranchland, the Disney Wilderness Preserve has been restored to Pine savanna under ownership of The Nature Conservancy. Prescribed burning at 3-yr intervals has transformed pastures to pine savannas, interspersed with cypress swamps and some hardwood stands. TNC is actively managing to minimize invasive species and restore red-cockaded woodpecker to the site. The dominant slash pine (Pinus elliotii) and longleaf (P. palustris) form a sparse canopy over palmetto (Serenoa repens) and rhizomatous dwarf shrubs, including dwarf live oak (Quercus minima), runner oak (Q. elliottii), and blueberry (Vaccinium) and grass species, include wiregrass (Aristida stricta). We observed a single loblolly pine (P. taeda). Much of the mesic flatwoods remain saturated from May to September from almost daily afternoon thunderstorms, sometimes short-duration, often high-intensity.
On arrival, lab Manager Jordan Luongo and I were briefed by Beatriz on site history, layout, and protocols. She discussed options for accommodating our seed traps during controlled burns, which can come with limited notice. She generously offered to facilitate moving our traps aside during burns and contacting us on how to redeploy them. Our reaction to individual burns will be complicated by the distance and travel expense.
As is typical for this time of year, many of the roads held up to ½ m of water; 4WD is essential. We worked around the typical thunderstorms, establishing seed traps at three NEON sites 6, 8, and 10.
Cone counts supplement mast estimates from seed trap data, using the model and code in the R package MASTIF. Throughout this site, pines support sparse foliage and cone production. Female cones fertilized in spring develop over the current and subsequent growing season to release seeds in autumn and winter of the following year. Sparse canopies facilitated direct cone counts, in three cohorts. Open cones at the time of our visit in 2018 released seeds in winter of 2017. Consistent with previous convention, we call this the “2017 seed year”. Fully developed but unopened cones on trees at the time of our visit were initiated in spring 2017 and will release seed beginning in autumn of 2018. Undeveloped seeds were initiated in 2018. From cone counts, it became clear that 2017 was a relatively strong seed year. From sparse unopened cones we expect small seed crops in 2018 and 2019.
Wildlife observed by us included white-tailed deer, diverse songbirds, Florida sandhill cranes, great blue heron, little blue heron, cattle egret, red-shouldered hawk. Evidence of feral pig activity is common.
Plot 10 represents palmetto-dominated savannas, with several shrub oaks, Vaccinium, and grasses. The water table was at the surface, but there was no standing water within the plot. We installed 6 seed traps and counted cones from the three cohorts on trees within 20 m of the plot center.
Having been burned the week before our arrival, Plot 6 presented us with blackened soils and stems. Already there was evidence of regrowth of palmetto and grasses. Despite near complete consumption of understory foliage during the burn, it was clear that palmetto was a dominant species. We installed six seed traps and counted cones on trees.
At the southern end of the site, plot 8 supported a diverse understory beneath a sparse slash pine overstory. Here again, we completed six seed traps and cone counts.