DOI: 10.5061/dryad.44j0zpcfs
title: Fitness, risk taking, and spatial behavior covary with boldness in experimental vole populations

description: Individuals of a population may vary along a pace-of-life syndrome from
 highly fecund, short-lived, bold, dispersive ‘fast’ types at one end of
 the spectrum to less fecund, long-lived, shy, plastic ‘slow’ types at the
 other end. Risk-taking behaviour might mediate the underlying life-history
 trade-off but empirical evidence supporting this hypothesis is still
 ambiguous. Using experimentally created populations of common voles
 (Microtus arvalis) - a species with distinct seasonal life-history
 trajectories - we aimed to test whether individual differences in boldness
 behaviour co-vary with risk-taking, space use, and fitness. We quantified
 risk taking, space use (via automated tracking), survival and reproductive
 success (via genetic parentage analysis) in 8 to 14 experimental,
 mixed-sex populations of 113 common voles of known boldness type in large
 grassland enclosures over a significant part of their adult life span and
 two reproductive events. Populations were assorted to contain extreme
 boldness types (bold or shy) of both sexes. Bolder individuals took more
 risks than shyer ones, which did not affect survival. Bolder males but not
 females produced more offspring than shy conspecifics. Daily home range
 and core area sizes, based on 95% and 50% Kernel density estimates (20 ±
 10 per individual, n = 54 individuals), were highly repeatable over time.
 Individual space use unfolded differently for sex-boldness type
 combinations over the course of the experiment. While day ranges decreased
 for shy females, they increased for bold females and all males. Space use
 trajectories may, hence, indicate differences in coping styles when
 confronted with a novel social and physical environment. Thus,
 inter-individual differences in boldness predict risk taking under near
 natural conditions and have consequences for fitness in males, which have
 a higher reproductive potential than females. Given extreme inter- and
 intra-annual fluctuations in population density in the study species and
 its short life span, density-dependent fluctuating selection operating
 differently on the sexes might maintain (co)variation in boldness, risk
 taking and pace-of-life.
description: Our study had three steps (Table 1): we (a) captured individuals
 from free ranging populations, and selected the extreme boldness types to
 compose experimental populations, (b) released experimental populations of
 both sexes into near-natural large outdoor enclosures and recorded space
 use and risk taking with indirect telemetry methods (ART and RFID) over
 two reproductive events (5-6 weeks), (c) recaptured individuals from
 outdoor enclosures to monitor survival and estimate reproductive success
 based on parentage analysis. All individuals were wild
 captured. Boldness tests were assessed repeatedly in standard test for
 animal personality in the laboratory before individuals were sorted into
 experimental populations and brought outside into the
 enclosures.
description: The data set is structured in two separate files. The file
 "DataAnimals" contains more detailed information on the
 personality tests of individuals, like single measured variables, while in
 the "Data" file data is shown that is the basis of the
 statistical analysis presented in the manuscript. Cells with NA represent
 missing values for the respected variable for an individual. This mostly
 refers to the data on visits to the riskier area of the enclosure which
 could only be obtained for a subset of individuals.