DOI: 10.5061/dryad.z08kprrj2
title: Linking spatial variations in life-history traits to environmental conditions across American black bear populations

description: Spatial variations in food availability may influence life-history traits
 of wildlife species, particularly in capital breeding species that store
 energy when food is widely available and catabolize it during
 energy-intensive reproductive periods. The reproductive success of capital
 breeders is thus highly dependent on the accumulation of fat reserves.
 Reproductive success may also improve with access to alternative food
 resources provided by environments with strong human footprint and
 anthropogenic disturbances, but these environments may also increase
 mortality risks of wildlife. We performed a systematic review to extract
 reproduction and survival traits reported in studies on the American black
 bear (Ursus americanus), a capital breeder. Based on 94 studies widely
 distributed across North America, we conducted meta-regression analyses to
 assess whether interpopulation variation in age at primiparity, litter
 size of cubs, annual cub survival, and annual survival of adult females
 were associated with environmental conditions, that is, habitat quality,
 habitat productivity, and anthropogenic disturbances. We found that mean
 age at primiparity decreased from around 5 to 4 years old in areas with
 the highest habitat quality and productivity as well as the highest human
 population densities compared with those with poor habitat quality and
 productivity and low human population densities. Mean litter size
 increased by approximately 13% (from 2 to 2.25 cubs per litter) in areas
 with the highest compared with the lowest proportion of deciduous forest,
 while cub survival increased by about 13% (from 60% to 73%) in areas with
 the highest compared with the lowest coverage of agricultural crops. Adult
 female survival decreased from 92% to 85% in areas where hunting was
 allowed. These results provide new insights into the factors associated
 with variations in reproductive success and survival across populations of
 a widely distributed species, demonstrating the impact of both natural and
 anthropogenic factors. Our study highlights the necessity of considering
 the ongoing changes in the distribution and growth of potential food
 resources, as well as the growing encroachment of humans into wildlife
 habitats, when planning management and conservation actions at the scale
 of a species distribution range.
description: # Linking spatial variations in life-history traits to environmental
 conditions across American black bear populations Investigators
 information: Name: Lisyanne Metthe (principal investigator & contact
 for questions) Institution 1: Ministère de l'Environnement, de la
 Lutte contre les changements climatiques, de la Faune et des Parcs Address
 1: 880 chemin Ste-Foy, Quebec City, QC G1S 4X4, Canada Institution 2:
 Laval University Address 2: 1045 avenue de la Médecine, Québec City, QC
 G1V 0A6, Canada Email:
 [lisyanne.metthe.1@ulaval.ca](mailto:lisyanne.metthe@environnement.gouv.qc.ca) Name: Christian Dussault Institution 1: Ministère de l'Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs Address 1: 880 chemin Ste-Foy, Quebec City, QC G1S 4X4, Canada Institution 2: Laval University Address 2: 1045 avenue de la Médecine, Québec City, QC G1V 0A6, Canada Email: [christian.dussault@environnement.gouv.qc.ca](mailto:christian.dussault@environnement.gouv.qc.ca) Name: Sandra Hamel Institution: Laval University Address: 1045 avenue de la Médecine, Québec City, QC G1V 0A6, Canada Email: [sandra.hamel@bio.ulaval.ca](mailto:sandra.hamel@bio.ulaval.ca) Date of data collection: August 2019 to December 2020 The first four databases contain the data extracted for each life history trait, as well as the geographically associated environmental data, used for the meta-analyses and meta-regressions in this study. The fifth database contains the data used correlation analyses between life-history traits. Information about geographic location of data collection: Our study is based on 123 studies carried out in different regions of North America, totalling 16 studies in 5 Canadian provinces, 106 studies in 34 American states, and one study in Mexico. NOTE: In all data files, NA is a missing data point. FIRST DATA FILE "ap.txt" - analyses on age at primiparity Description: Contains data on studies that measured age at primiparity of black bear females, as well as the environmental data we extracted from the associated geographies. Paired with this data file, the R script "age_at_primiparity.R" can be used to reproduce the analyses. Creation date: March 6, 2023 1 X Row number in the original database [unitless]. 2 NO Paper number, associated with the EndNote database [unitless]. 3 REF Reference of the paper, listing the name of the authors [unitless]. 4 UNIQUE_ID Unique ID of the study area [unitless]. 5 LONG_CENT Longitude - central geographic point of the study area [decimal degrees]. 6 LAT_CENT Latitude - central geographic point of the study area [decimal degrees]. 7 AP_MEAN Mean age at primiparity for the study area reported in the paper [unitless]. 8 AP_SE Standard error of age at primiparity for the study area reported in the paper [unitless]. 9 AP_SD Standard deviation of age at primiparity for the study area reported in the paper [unitless]. 10 AP_SE_CALCUL Estimated standard error of age at primiparity for the study area (see Methods) [unitless]. 11 AP_SD_CALCUL Estimated standard deviation of age at primiparity for the study area (see Methods) [unitless]. 12 AP_N Sample size for the estimation of age at primiparity for the study area reported in the paper [unitless]. 13 Y_1_A_t_5 The year representing five years before the first year of the study (i.e. first year - 5) [unitless]. 14 Y_1_B_t_5 The year representing five years before the last year of the study (i.e. last year - 5) [unitless]. 15 PDF Proportion of deciduous forests estimated for the study area [%]. 16 FTA Mast tree diversity index estimated for the study area [unitless]. 17 FSA_t_5 Berry availability index estimated for the study area at time t-5 [unitless]. 18 SPP_t_5 Spring plant productivity index estimated for the study area at time t-5 [unitless]. 19 LPA_t_5 Length of plant accessibility period estimated for the study area at time t-5 [days]. 20 DST_t_5_C Mean daily spring temperatures estimated for the study area at time t-5 [Celsius]. 21 DPS_t_5 Mean daily total precipitation in summer estimated for the study area at time t-5 [kg/m^2]. 22 AAC_t_5 Index of availability of food resources from agricultural crops estimated for the study area at time t-5 [%]. 23 AAF_t_5 Index of availability of other anthropogenic food resources estimated for the study area at time t-5 [%]. SECOND DATA FILE "lsc.txt"- analyses on litter size Description: Contains data on studies that measured litter size of cubs of female black bears, as well as the environmental data we extracted from the associated geographies. Paired with this data file, the R script "litter_size.R" can be used to reproduce the analyses. Creation date: March 6, 2023 1 X Row number in the original database [unitless]. 2 NO Paper number, associated with the EndNote database [unitless]. 3 REF Reference of the paper, listing the name of the authors [unitless]. 4 UNIQUE_ID Unique ID of the study area [unitless]. 5 LONG_CENT Longitude - central geographic point of the study area [decimal degrees]. 6 LAT_CENT Latitude - central geographic point of the study area [decimal degrees]. 7 LSC_MEAN Mean litter size (cubs of the year) for the study area reported in the paper [unitless]. 8 LSC_SD_CALCUL Estimated standard deviation of litter size of cubs for the study area reported in the paper [unitless]. 9 LSC_SE_CALCUL Estimated standard error of litter size for the study area (see Methods) [unitless]. 10 LSC_SD Standard deviation of litter size for the study area (see Methods) [unitless]. 11 LSC_SE Standard error of litter size for the study area reported in the paper [unitless]. 12 LSC_N_LITTER Number of litters observed in dens to estimate litter size for the study area reported in the paper [unitless]. 13 Y_1_A_t_1 One year before the first year of the study (first year - 1) [unitless]. 14 Y_1_B_t_1 One year before the last year of the study (last year - 1) [unitless]. 15 Y_2_A_t_1 For studies with two study periods: One year before the first year of the second study period (first year second period - 1) [unitless]. 16 Y_2_B_t_1 For studies with two study periods: One year before the last year of the second study period (last year second period - 1) [unitless]. 17 PDF Proportion of deciduous forests estimated for the study area [%]. 18 FTA Mast tree diversity index estimated for the study area [unitless]. 19 FSA_t_1 Berry availability index estimated for the study area at time t-1 [unitless]. 20 SPP_t_1 Spring plant productivity index estimated for the study area at time t-1 [unitless]. 21 LPA_t_1 Length of plant accessibility period estimated for the study area at time t-1 [days]. 22 DST_t_1_C Mean daily spring temperatures estimated for the study area at time t-1 [Celsius]. 23 DPS_t_1 Mean daily total precipitation in summer estimated for the study area at time t-1 [kg/m^2]. 24 AAC_t_1 Index of availability of food resources from agricultural crops estimated for the study area at time t-1 [%]. 25 AAF_t_1 Index of availability of other anthropogenic food resources estimated for the study area at time t-1 [%]. THIRD DATA FILE "cs.txt" - analyses on cub survival Description: Contains data on studies that measured annual survival cubs in black bears, as well as the environmental data we extracted from the associated geographies. Paired with this data file, the R script "cub_survival.R" can be used to reproduce the analyses. Creation date: March 6, 2023 1 X Row number in the original database [unitless]. 2 NO Paper number, associated with the EndNote database [unitless]. 3 REF Reference of the paper, listing the name of the authors [unitless]. 4 UNIQUE_ID Unique ID of the study area [unitless]. 5 LONG_CENT Longitude - central geographic point of the study area [decimal degrees]. 6 LAT_CENT Latitude - central geographic point of the study area [decimal degrees]. 7 HUNT Hunting activity in the study area. Y = presence of hunting, N = no hunting, NA = authors did not mentioned anything about hunting activity in the study area [unitless]. 8 CS_M.F Mean cub survival (males & females) until the second winter (to 1 year old) for the study area reported in the paper [unitless]. 9 CS_M.F_LOW Lower limit of the confidence interval of cub survival (males & females) for the study area reported in the paper [%]. 10 CS_M.F_UP Upper limit of the confidence interval of cub survival (males & females) for the study area reported in the paper [%]. 11 CS_M.F_SD Standard deviation of cub survival (males & females) for the study area reported in the paper [unitless]. 12 CS_M.F_SE Standard error of cub survival (males & females) for the study area reported in the paper [unitless]. 13 CS_M.F_N Number of cubs observed in dens to estimate cub survival (males & females) for the study area reported in the paper [unitless]. 14 Y_1_A_t First year of the study [unitless]. 15 Y_1_B_t Last year of the study [unitless]. 16 Y_2_A_t For studies with two study periods: First year of the second study period [unitless]. 17 Y_2_B_t For studies with two study periods: Last year of the second study period [unitless]. 18 PDF Proportion of deciduous forests estimated for the study area [%]. 19 FTA Mast tree diversity index estimated for the study area [unitless]. 20 FSA_t Berry availability index estimated for the study area at time t [unitless]. 21 SPP_t Spring plant productivity index estimated for the study area at time t [unitless]. 22 LPA_t Length of plant accessibility period (number of days) estimated for the study area at time t [days]. 23 DST_t_C Mean daily spring temperatures (in Celsius) estimated for the study area at time t [Celsius]. 24 DPS_t Mean daily total precipitation in summer estimated for the study area at time t [kg/m^2]. 25 AAC_t Index of availability of food resources from agricultural crops estimated for the study area at time t [%]. 26 AAF_t Index of availability of other anthropogenic food resources estimated for the study area at time t [%]. FOURTH DATA FILE "asf.txt" - analyses on adult female survival Description: Contains data on studies that measured annual survival of adult female black bears, as well as the environmental data we extracted from the associated geographies. Paired with this data file, the R script "adult_female_survival.R" can be used to reproduce the analyses. Creation date: March 6, 2023 1 X Row number in the original database [unitless]. 2 NO Paper number, associated with the EndNote database [unitless]. 3 REF Reference of the paper, listing the name of the authors [unitless]. 4 UNIQUE_ID Unique ID of the study area [unitless]. 5 LONG_CENT Longitude - central geographic point of the study area [decimal degrees]. 6 LAT_CENT Latitude - central geographic point of the study area [decimal degrees]. 7 HUNT Hunting activity in the study area. Y = presence of hunting, N = no hunting, NA = authors did not mentioned anything about hunting activity in the study area [unitless]. 8 AS_F Mean adult female survival for the study area reported in the paper [unitless]. [This variable involves a compilation of survival data by different age classes (i.e. 2 years old and over, 3 years old and over, 4 years old and over and 5 years old and over, see Methods)] 9 AS_F_AGE Age class of females to estimate adult survival for the study area reported in the paper (i.e. 2 years old and over, 3 years old and over, 4 years old and over and 5 years old and over) [unitless]. 10 AS_F_CI_LOW Lower limit of the confidence interval of adult female survival for the study area reported in the paper [%]. 11 AS_F_CI_UP Upper limit of the confidence interval of adult female survival for the study area reported in the paper [%]. 12 AS_F_PER Percentage of confidence interval of adult female survival for the study area reported in the paper [%]. 13 AS_F_SD Standard deviation of adult female survival for the study area reported in the paper [unitless]. 14 AS_F_SE Standard error of adult female survival for the study area reported in the paper [unitless]. 15 AS_F_N Number of adult females to estimate adult female survival for the study area reported in the paper [unitless]. 16 Y_1_A_t First year of the study [unitless]. 17 Y_1_B_t Last year of the study [unitless]. 18 Y_2_A_t For studies with two study periods: First year of the second study period [unitless]. 19 Y_2_B_t For studies with two study periods: Last year of the second study period [unitless]. 20 PDF Proportion of deciduous forests estimated for the study area [%]. 21 FTA Mast tree diversity index estimated for the study area [unitless]. 22 FSA_t Berry availability index estimated for the study area at time t [unitless]. 23 SPP_t Spring plant productivity index estimated for the study area at time t [unitless]. 24 LPA_t Length of plant accessibility period estimated for the study area at time t [days]. 25 DST_t_C Mean daily spring temperatures estimated for the study area at time t [Celsius]. 26 DPS_t Mean daily total precipitation in summer estimated for the study area at time t [kg/m^2]. 27 AAC_t Index of availability of food resources from agricultural crops estimated for the study area at time t [%]. 28 AAF_t Index of availability of other anthropogenic food resources estimated for the study area at time t [%]. FIFTH DATA FILE "repro_lht.txt" - analyses on life-history traits covariation Description: Contains all life-history trait data for black bear populations compiled from the studies, i.e. age at primiparity, litter size of cubs, annual cub survival, and annual adult female survival, for correlation analyses between these variables. Paired with this data file, the R script "figure 6.R" can be used to reproduce the analyses. Creation date: March 6, 2023 1 AP_MEAN Mean age at primiparity for the study area reported in the paper [unitless]. 2 LSC_MEAN Mean litter size of cubs (cubs of the year) for the study area reported in the paper [unitless]. 3 CS_M.F Mean cubs survival (males & females) until the second winter (to 1 year old) for the study area reported in the paper [unitless]. 4 AS_F Mean adult female survival for the study area reported in the paper [unitless]. [This variable involves a compilation of survival data by different age classes (i.e. 2 years old and over, 3 years old and over, 4 years old and over and 5 years old and over, see Methods).]