DOI: 10.5061/dryad.20p4g44
title: Data from: Environmental and demographic drivers of male mating success vary across sequential reproductive episodes in a polygynous breeder

description: Ecological and social factors underpinning the inequality of male mating
 success in animal societies can be related to sex ratio, sexual conflict
 between breeders, effects of non-breeders, resource dispersion, climatic
 conditions, and the various sequential stages of mating competition that
 constitute the sexual selection process. Here, we conducted an
 individual-based study to investigate how local resource availability and
 demography interact with annual climate conditions to determine the degree
 of male mating inequality, and thus opportunity for sexual selection
 across two sequential reproductive episodes (harem and subsequent mate
 acquisition) in a naturally regulated (feral) horse population in Sable
 Island National Park Preserve, Canada. Using a 5-year, spatially explicit,
 mark-resight dataset and hierarchical mixed-effects linear modelling, we
 evaluated the influence of adult sex ratio (ASR) on mating success, and
 then tested for effects of freshwater availability, density, unpaired male
 abundance, and precipitation during each breeding season. Unpaired male
 abundance, freshwater availability, and ASR differed in their effects on
 male mating success according to year and selection episode. Opportunity
 for sexual selection in males associated with harem acquisition increased
 with ASR, and unpaired male abundance further explained weather-related
 inter-annual variation after accounting for ASR. In contrast, once a harem
 was secured, ASR had little effect on male mating inequality in regards to
 acquiring additional females, while inter-annual variation in mating
 inequality increased with decreasing freshwater availability. Our findings
 show that local demography, resource availability, and weather effect
 opportunity for sexual selection in males differently depending on
 selection episode, and can attenuate or accentuate effects of ASR.
description: male sexual selection
 data across reproductive episodes--manning&mcloughinData are from an
 empirical study of counts and demographic rates of spatially explicit
 segments of a feral horse population and associated distances to nearest
 permanent freshwater sources on Sable Island, Canada (2008-2013). Field
 Labels Year=year, Itotal= georeferenced estimate of standardized variance
 in male mating success (variance/[mean mating success2]) for a given
 dominant male horse during a specific breeding season, Iband=
 georeferenced estimate of opportunity for male sexual selection associated
 with acquiring a harem, Imaresperband= georeferenced estimate of
 opportunity for male selection associated with acquiring mates once a male
 attained a harem, Band=name of band (group) of breeding feral horses
 consisting of a dominant male (stallion) with a harem of females,
 TotASR=adult sex ratio (mean number of adult males/[adult males + adult
 females] with ≥1 buffered locations that overlapped ≥1 locations of the
 ith band over the course of the field season in the jth year),
 NrstWater=source of nearest freshwater (hole dug by horses or naturally
 occurring permanent pond), AdultFemales=count of adult female horses,
 AveDNrstPond=distance to nearest permanent freshwater pond (meters),
 AveDensAllhorses=average density of all horses over an entire breeding
 season per km2 of terrestrial area across a band’s buffered locations,
 DensSumBachD= total number of unpaired adult males over an entire breeding
 season per km2 of terrestrial area across a band’s buffered locations,
 SummerTotalPrecipCM=total summer precipitation from June through
 August