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Data from: Partitioning drivers of spatial genetic variation for a continuously-distributed population of boreal caribou: implications for management unit delineation
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Priadka, Pauline; Manseau, Micheline; Trottier, Tim; Hervieux, Dave; Galpern, Paul; McLoughlin, Philip D.; Wilson, Paul J. — 2018-12-18 Isolation-by-distance (IBD) is a natural pattern not readily incorporated into theoretical models nor traditional metrics for differentiating populations, although clinal genetic differentiation can be characteristic of many wildlife species. Landscape features can also drive population structure additive to baseline IBD resulting in differentiation through isolation-by-resistance (IBR). We assessed the population genetic structure of boreal caribou across western Canada using non-spatial (STRUCTURE) and spatial (MEMGENE) clustering methods and investigated the relative contribution of IBD and IBR on genetic variation of 1221 boreal caribou multilocus genotypes across western Canada. We further introduced a novel approach to compare the partitioning of individuals into management units (MU) and assessed levels of genetic connectivity under different MU scenarios. STRUCTURE delineated five genetic clusters while MEMGENE identified finer-scale differentiation across the study area. IBD was significant and did not differ for males and females both across and among detected genetic clusters. MEMGENE landscape analysis further quantified the proportion of genetic variation contributed by IBD and IBR patterns, allowing for the relative importance of spatial drivers, including roads, water bodies and wildfires, to be assessed and incorporated into the characterization of population structure for the delineation of MUs. Local population units, as currently delineated in the boreal caribou recovery strategy, do not capture the genetic variation and connectivity of the ecotype across the study area. Here, we provide the tools to assess fine-scale spatial patterns of genetic variation, partition drivers of genetic variation and evaluate the best management options for maintaining genetic connectivity. Our approach is highly relevant to vagile wildlife species that are of management and conservation concern and demonstrate varying degrees of IBD and IBR with clinal spatial genetic structure that challenges the delineation of discrete population boundaries.
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Data from: Environmental and demographic drivers of male mating success vary across sequential reproductive episodes in a polygynous breeder
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Manning, Jeffrey A.; McLoughlin, Philip D. — 2019-04-15 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.
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Insect-mediated apparent competition between mammals in a boreal food web
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Labadie, Guillemette; McLoughlin, Philip D.; Hebblewhite, Mark; Fortin, Daniel — 2021-06-21 <p>Datasets generated and analyzed within the study area located in the Côte-Nord region of Québec, Canada. "DataFinal_Vegetation.csv" was used to evaluate the availability of deciduous vegetation (column <em>Cover_Deciduous</em>) in stands impacted by the spruce budworm (SBW, severity index values presented in column <em>SBW_SevCum</em>) outbreak and test our prediction that the reduction in canopy cover caused by SBW in coniferous stands would result in greater deciduous vegetation. We determined the percentage cover of deciduous vegetation for two height strata ([0-1m] and [1-3m] classes, column <em>Stratum</em>).</p> <p>"DataFinal_Moose_density.csv" was used to assess the influence of SBW outbreak (<em>SBW_SevCum</em>) on moose abundance by comparing moose densities (<em>Density</em>) before (<em>year </em>= 2006) and during SBW outbreak (<em>year </em>= 2018). We also determined the effect of the percentage cover of deciduous vegetation (<em>Broadleaf</em>) and the percentage cover of salvage-logged forest stands (<em>SBW_cut_2018Factor</em>) on moose densities.</p> <p>"DataFinal_RSF_Caribou.csv" and "DataFinal_RSF_Wolves.csv" were used to develop Resource Selection Functions for caribou and wolves to assess habitat selection. RSFs compare resource characteristics of observed (scored 1) and random (scored 0) locations presented in column <em>case</em>. Habitat characteristics (<em>columns conif_dense, conif_open, mixed, open, other, burned0_5, burned6_20, burned21_, cut0_5, cut6_20, cut21_</em>) was extracted from the Canadian National Forest Inventory (NFI) forest cover maps. Land cover maps were updated every year by adding roads, recent (&lt;5 years), regenerating (6–20 years) and old (21–50 years) cutblocks/fires based on information provided annually by local forestry companies and from the Canadian National Fire Database (CNFDB). SBW outbreak was characterized by its cumulative severity (<em>SBW_SevCum</em>), and also if infested stands were logged (<em>SBW_Cut</em>). As our study focused on the survival of boreal caribou, we added the mortality status for each individual  (<em>DeadStatus, </em>remained alive throughout the study = 0, died = 1<em>) </em>and interaction terms (i.e. the multiplication of two columns) <em>Dead_SBW_SevCum </em>and <em>Dead_SBW_Cut. </em></p> <p>Finally, we used "DataFinal_SurvivalAnalysis.csv" to evaluate whether the proportion of natural (<em>Prop_burned</em>) and anthropogenic (<em>Prop_Cut0_5, Prop_Cut6_20, Prop_SBW_cut</em>) disturbances within winter home range had an effect on the mortality risk of caribou (determined with the mortality status column <em>Dead : </em>remained alive throughout the study = 0, died = 1). For this analysis, we determined the individual ID (<em>ID</em>), the years during they were monitored (<em>Year</em>), and the time was defined as the total period of monitoring for that individual (<em>Time</em>). </p>
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Data from: Individual quality and age but not environmental or social conditions modulate costs of reproduction in a capital breeder
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Debeffe, Lucie; Poissant, Jocelyn; McLoughlin, Philip D. — 2018-05-08 Costs associated with reproduction are widely known to play a role in the evolution of reproductive tactics with consequences to population and eco-evolutionary dynamics. Evaluating these costs as they pertain to species in the wild remains an important goal of evolutionary ecology. Individual heterogeneity, including differences in individual quality (i.e., among-individual differences in traits associated with survival and reproduction) or state, and variation in environmental and social conditions can modulate the costs of reproduction; however, few studies have considered effects of these factors simultaneously. Taking advantage of a detailed, long-term dataset for a population of feral horses (Sable Island, Nova-Scotia, Canada), we address the question of how intrinsic (quality, age), environmental (winter severity, location), and social conditions (group size, composition, sex ratio, density) influence the costs of reproduction on subsequent reproduction. Individual quality was measured using a multivariate analysis on a combination of four static and dynamic traits expected to depict heterogeneity in individual performance. Female quality and age interacted with reproductive status of the previous year to determine current reproductive effort, while no effect of social or environmental covariates was found. High quality females showed higher probabilities of giving birth and weaning their foal regardless of their reproductive status the previous year, while those of lower quality showed lower probabilities of producing foals in successive years. Middle-aged (prime) females had the highest probability of giving birth when they had not reproduced the year before but no such relationship with age was found among females that had reproduced the previous year, indicating that prime-aged females bear higher costs of reproduction. We show that individual quality and age were key factors modulating the costs of reproduction in a capital breeder but that environmental or social conditions were not, highlighting the importance of considering multiple factors when studying costs of reproduction.

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(Author: McLoughlin, Philip D.)

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