DOI: 10.5061/dryad.b75j7
title: Data from: Energy benefits and emergent space use patterns of an empirically parameterized model of memory-based patch selection

description: Many species frequently return to previously visited foraging sites. This
 bias towards familiar areas suggests that remembering information from
 past experience is beneficial. Such a memory-based foraging strategy has
 also been hypothesized to give rise to restricted space use (i.e. a home
 range). Nonetheless, the benefits of empirically derived memory-based
 foraging tactics and the extent to which they give rise to restricted
 space use patterns are still relatively unknown. Using a combination of
 stochastic agent-based simulations and deterministic integro-difference
 equations, we developed an adaptive link (based on energy gains as a
 foraging currency) between memory-based patch selection and its resulting
 spatial distribution. We used a memory-based foraging model developed and
 parameterized with patch selection data of free-ranging bison Bison bison
 in Prince Albert National Park, Canada. Relative to random use of food
 patches, simulated foragers using both spatial and attribute memory are
 more efficient, particularly in landscapes with clumped resources.
 However, a certain amount of random patch use is necessary to avoid
 frequent returns to relatively poor-quality patches, or avoid being caught
 in a relatively poor quality area of the landscape. Notably, in landscapes
 with clumped resources, simulated foragers that kept a reference point of
 the quality of recently visited patches, and returned to previously
 visited patches when local patch quality was poorer than the reference
 point, experienced higher energy gains compared to random patch use.
 Furthermore, the model of memory-based foraging resulted in restricted
 space use in simulated landscapes and replicated the restricted space use
 observed in free-ranging bison reasonably well. Our work demonstrates the
 adaptive value of spatial and attribute memory in heterogeneous
 landscapes, and how home ranges can be a byproduct of non-omniscient
 foragers using past experience to minimize temporal variation in energy
 gains.
description: Squared displacement and
 utilization distribution data for Merkle et al. 2016
 OikosThe data file is an
 excel database (.xlsx) with two sheets. Data summarized in both sheets
 were derived from the movements of 25 adult female bison, GPS collared for
 one to two years between 2005 and 2013 in Prince Albert National Park
 (Canada). GPS collars took locations every 3 hours during the monitoring
 period. Sheet 1 (named “bison_MSD_data”) provides the data for calculating
 Mean Squared Displacement (MSD) over the course of one year for 41
 bison-years. Time is based on a biological year, which starts on 1 April.
 The units of the squared displacement column is squared kilometers. Sheet
 2 (named “bison_UD_data”) provides the data for calculating the
 Utilization Distribution of bison across meadows within Prince Albert
 National Park. The database is organized by meadow ID, and includes the X
 and Y coordinates (projection: CRS("+proj=utm +zone=13 +ellps=GRS80
 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs")) of the centroid of each
 meadow. The final column represents an index of bison density, calculated
 as the total number of unique visits of all 25 individuals to meadows
 during the monitoring period.data4OikosMS.xlsx