Droughts reshape apex predator space use and intraguild overlap
Data files
Sep 13, 2024 version files 415.63 KB
-
encounters_200m.csv
12.36 KB
-
encounters_400m.csv
19.21 KB
-
home_range_table.csv
116.42 KB
-
overlap_50_beta.csv
9.46 KB
-
overlap_50_binom.csv
91.33 KB
-
overlap_95_beta.csv
51.35 KB
-
overlap_95_binom.csv
99.28 KB
-
README.md
16.22 KB
Abstract
Droughts are increasing in frequency and severity globally due to climate change, leading to changes in resource availability that may have cascading effects on animal ecology. Resource availability is a key driver of animal space use, which in turn influences interspecific interactions like intraguild competition. Understanding how climate-induced changes in resource availability influence animal space use, and how species-specific responses scale up to affect intraguild dynamics, is necessary for predicting broader community-level responses to climatic changes. Although several studies have demonstrated the ecological impacts of drought, the behavioral responses of individuals that scale up to these broader-scale effects are not well known, particularly among animals in top trophic levels like large carnivores. Furthermore, we currently lack understanding of how the impacts of climate variability on individual carnivore behavior are linked to intraguild dynamics, in part because multi-species datasets collected at timescales relevant to climatic changes are rare. Using 11 years of GPS data from four sympatric large carnivore species in southern Africa – lions (Panthera leo), leopards (Panthera pardus), African wild dogs (Lycaon pictus), and cheetahs (Acinonyx jubatus) – spanning 4 severe drought events, we test whether drought conditions impact 1) large carnivore space use, 2) broad-scale intraguild spatial overlap, and 3) fine-scale intraguild interactions. Drought conditions expanded space use across species, with carnivores increasing their monthly home range sizes by 35% (wild dogs) to 66% (leopards). Drought conditions increased the amount of spatial overlap between lions and subordinate felids (cheetahs and leopards) by up to 119%, but only lion-cheetah encounter rates were affected by these changes, declining in response to drought. Our findings reveal that drought has a clear signature on the space use of multiple sympatric large carnivore species, which can alter spatiotemporal partitioning between competing species. Our study thereby illuminates the links between environmental change, animal behavior, and intraguild dynamics. While fine-scale avoidance strategies may facilitate intraguild coexistence during periodic droughts, large carnivore conservation may require considerable expansion of protected areas or revised human-carnivore coexistence strategies to accommodate the likely long-term increased space demands of large carnivores under projected increases in drought intensity.
README: Droughts reshape apex predator space use and intraguild overlap
https://doi.org/10.5061/dryad.k98sf7mgm
The dataset contains data for estimating the effect of drought (Standard Precipitation Index) on the 95% and 50% home range sizes of four African carnivore species (African wild dogs, cheetahs, leopards, and lions), the probability and amount of overlap between carnivore species' 95% and 50% home ranges, and the number of interspecific encounters at 200m and 400m distance thresholds. The dataset was collected from GPS collars from the four aforementioned African carnivore species. Fix rates varied between 5 minutes and 3 hours, and were regularized to 3 hour intervals. As each individual has different collar deployment lengths, we divided the data into monthly time periods, with these monthly periods beginning from the first date of each collar deployment.
Description of the data and file structures
overlap_95_beta.csv
Description: Contains data for estimating the effect of drought (SPI) on the amount of overlap between dyads for 95% home ranges. Each row represents the overlap coefficient between two individuals of different species in a given Year-Month (e.g. January 2024) and its associated environmental data.
Variables
id_1: Name of the first individual in dyad (e.g. Bongwe)
id_2: Name of the second individual in dyad (e.g. Qamar)
Species_1: Species of the first individual in dyad (e.g. African wild dog)
Species_2: Species of the second individual in dyad (e.g. Cheetah)
dyad_id: Identifier of individual dyad (e.g. Bongwe-Qamar)
overlap: Overlap coefficient for 95% home range calculated using Bhattacharya's affinity metric. A value between 0 and 1.
year: Year that overlap measurement was collected in (numeric)
Month: Month that overlap measurement was collected in (numeric)
YearMon: Year-Month (e.g. January 2024) that overlap measurement was collected in
season: 'Wet' or 'Dry'
label: Unique identifier for this row of data (using year and season (e.g., '2012 Wet 1', '2012 Wet 2', etc.)
monthly_spi: Standard Precipitation Index value representing drought conditions at the monthly scale. Negative values represent dry conditions and positive values represent wet conditions.
threemonth_spi: Standard Precipitation Index value representing drought conditions for the three months prior to the overlap measurement. Negative values represent dry conditions and positive values represent wet conditions.
sixmonth_spi: Standard Precipitation Index value representing drought conditions for the six months prior to the overlap measurement. Negative values represent dry conditions and positive values represent wet conditions.
prevyear_spi: Standard Precipitation Index value representing drought conditions for the twelve months prior to the overlap measurement. Negative values represent dry conditions and positive values represent wet conditions.
dyad_species: Species-level dyad (as opposed to individual-level dyad reported in 'dyad_id' column; e.g. African wild dog-cheetah)
Month_categorical: Month that overlap measurement was collected in (categorical)
Year_categorical: Year that overlap measurement was collected in (categorical)
File: overlap_50_beta.csv
Description: Contains data for estimating the effect of drought (SPI) on the amount of overlap between dyads for 50% core areas. Each row represents the overlap coefficient between two individuals of different species in a given Year-Month (e.g. January 2024) and its associated environmental data.
Variables
id_1: Name of the first individual in dyad (e.g. Bongwe)
id_2: Name of the second individual in dyad (e.g. Qamar)
Species_1: Species of the first individual in dyad (e.g. African wild dog)
Species_2: Species of the second individual in dyad (e.g. Cheetah)
dyad_id: Identifier of individual dyad (e.g. Bongwe-Qamar)
overlap: Overlap coefficient for 50% home range calculated using Bhattacharya's affinity metric. A value between 0 and 1.
year: Year that overlap measurement was collected in (numeric)
Month: Month that overlap measurement was collected in (numeric)
YearMon: Year-Month (e.g. January 2024) that overlap measurement was collected in
season: 'Wet' or 'Dry'
label: Unique identifier for this row of data (using year and season (e.g., '2012 Wet 1', '2012 Wet 2', etc.)
monthly_spi: Standard Precipitation Index value representing drought conditions at the monthly scale. Negative values represent dry conditions and positive values represent wet conditions.
threemonth_spi: Standard Precipitation Index value representing drought conditions for the three months prior to the overlap measurement. Negative values represent dry conditions and positive values represent wet conditions.
sixmonth_spi: Standard Precipitation Index value representing drought conditions for the six months prior to the overlap measurement. Negative values represent dry conditions and positive values represent wet conditions.
prevyear_spi: Standard Precipitation Index value representing drought conditions for the twelve months prior to the overlap measurement. Negative values represent dry conditions and positive values represent wet conditions.
dyad_species: Species-level dyad (as opposed to individual-level dyad reported in 'dyad_id' column; e.g. African wild dog-cheetah)
Month_categorical: Month that overlap measurement was collected in (categorical)
Year_categorical: Year that overlap measurement was collected in (categorical)
File: overlap_95_binom.csv
Description: Contains data for estimating the effect of drought (SPI) on the probability of overlap between dyads for 95% home ranges. Each row represents a binary description of whether there was (1) or was not (0) spatial overlap between two individuals of different species in a given Year-Month (e.g. January 2024) and the associated environmental data.
Variables
id_1: Name of the first individual in dyad (e.g. Bongwe)
id_2: Name of the second individual in dyad (e.g. Qamar)
Species_1: Species of the first individual in dyad (e.g. African wild dog)
Species_2: Species of the second individual in dyad (e.g. Cheetah)
dyad_id: Identifier of individual dyad (e.g. Bongwe-Qamar)
overlap: Overlap coefficient for 95% home range calculated using Bhattacharya's affinity metric. A value between 0 and 1.
year: Year that overlap measurement was collected in (numeric)
Month: Month that overlap measurement was collected in (numeric)
YearMon: Year-Month (e.g. January 2024) that overlap measurement was collected in
season: 'Wet' or 'Dry'
label: Unique identifier for this row of data (using year and season (e.g., '2012 Wet 1', '2012 Wet 2', etc.)
monthly_spi: Standard Precipitation Index value representing drought conditions at the monthly scale. Negative values represent dry conditions and positive values represent wet conditions.
threemonth_spi: Standard Precipitation Index value representing drought conditions for the three months prior to the overlap measurement. Negative values represent dry conditions and positive values represent wet conditions.
sixmonth_spi: Standard Precipitation Index value representing drought conditions for the six months prior to the overlap measurement. Negative values represent dry conditions and positive values represent wet conditions.
prevyear_spi: Standard Precipitation Index value representing drought conditions for the twelve months prior to the overlap measurement. Negative values represent dry conditions and positive values represent wet conditions.
dyad_species: Species-level dyad (as opposed to individual-level dyad reported in 'dyad_id' column; e.g. African wild dog-cheetah)
Month_categorical: Month that overlap measurement was collected in (categorical)
Year_categorical: Year that overlap measurement was collected in (categorical)
overlap_binary: A numeric representation of whether there was (1) or was not (0) overlap of the individuals' 95% home ranges within the monthly time period, derived from 'overlap' column.
File: overlap_50_binom.csv
Description: Contains data for estimating the effect of drought (SPI) on the probability of overlap between dyads for 50% core areas. Each row represents a binary description of whether there was (1) or was not (0) spatial overlap between two individuals of different species in a given Year-Month (e.g. January 2024) and the associated environmental data.
Variables
id_1: Name of the first individual in dyad (e.g. Bongwe)
id_2: Name of the second individual in dyad (e.g. Qamar)
Species_1: Species of the first individual in dyad (e.g. African wild dog)
Species_2: Species of the second individual in dyad (e.g. Cheetah)
dyad_id: Identifier of individual dyad (e.g. Bongwe-Qamar)
overlap: Overlap coefficient for 50% home range calculated using Bhattacharya's affinity metric. A value between 0 and 1.
year: Year that overlap measurement was collected in (numeric)
Month: Month that overlap measurement was collected in (numeric)
YearMon: Year-Month (e.g. January 2024) that overlap measurement was collected in
season: 'Wet' or 'Dry'
label: Unique identifier for this row of data (using year and season (e.g., '2012 Wet 1', '2012 Wet 2', etc.)
monthly_spi: Standard Precipitation Index value representing drought conditions at the monthly scale. Negative values represent dry conditions and positive values represent wet conditions.
threemonth_spi: Standard Precipitation Index value representing drought conditions for the three months prior to the overlap measurement. Negative values represent dry conditions and positive values represent wet conditions.
sixmonth_spi: Standard Precipitation Index value representing drought conditions for the six months prior to the overlap measurement. Negative values represent dry conditions and positive values represent wet conditions.
prevyear_spi: Standard Precipitation Index value representing drought conditions for the twelve months prior to the overlap measurement. Negative values represent dry conditions and positive values represent wet conditions.
dyad_species: Species-level dyad (as opposed to individual-level dyad reported in 'dyad_id' column; e.g. African wild dog-cheetah)
Month_categorical: Month that overlap measurement was collected in (categorical)
Year_categorical: Year that overlap measurement was collected in (categorical)
overlap_binary: A numeric representation of whether there was (1) or was not (0) overlap of the individuals' 50% home ranges within the monthly time period, derived from 'overlap' column.
File: encounters_400m.csv
Description: Contains data on the number of encounters between dyads within a 400m distance threshold. Each row represents the number of encounters between two individuals of different species in a given Year-Month (e.g. January 2024) and the associated environmental data.
Variables
Year: Year that encounter measurements were collected in (numeric)
Month: Month that encounter measurements were collected in (numeric)
YearMon: Year-Month (e.g. January 2024) that encounter measurements were collected in
number_encounters: number of encounters per month at 400m distance threshold (count)
threemonth_spi: Standard Precipitation Index value representing drought conditions for the three months prior to the encounters. Negative values represent dry conditions and positive values represent wet conditions.
prevyear_spi: Standard Precipitation Index value representing drought conditions for the twelve months prior to the encounters. Negative values represent dry conditions and positive values represent wet conditions.
season: 'Wet' or 'Dry'
Month_categorical: Month that encounter measurements were collected in (categorical)
Year_categorical: Year that encounter measurements were collected in (categorical)
dyad_id: Identifier of individual dyad (e.g. Bongwe-Qamar)
dyad_species: Species-level dyad (as opposed to individual-level dyad reported in 'dyad_id' column; e.g. African wild dog-cheetah)
File: encounters_200m.csv
Description: Contains data on the number of interspecific encounters within a 200m distance threshold. Each row represents the number of encounters between two individuals of different species in a given Year-Month (e.g. January 2024) and the associated environmental data.
Variables
Year: Year that encounter measurements were collected in (numeric)
Month: Month that encounter measurements were collected in (numeric)
YearMon: Year-Month (e.g. January 2024) that encounter measurements were collected in
number_encounters: number of encounters per month at 200m distance threshold (count)
threemonth_spi: Standard Precipitation Index value representing drought conditions for the three months prior to the encounters. Negative values represent dry conditions and positive values represent wet conditions.
prevyear_spi: Standard Precipitation Index value representing drought conditions for the twelve months prior to the encounters. Negative values represent dry conditions and positive values represent wet conditions.
season: 'Wet' or 'Dry'
Month_categorical: Month that encounter measurements were collected in (categorical)
Year_categorical: Year that encounter measurements were collected in (categorical)
dyad_id: Identifier of individual dyad (e.g. Bongwe-Qamar)
dyad_species: Species-level dyad (as opposed to individual-level dyad reported in 'dyad_id' column; e.g. African wild dog-cheetah)
File: home_range_table.csv
Description: Contains data on the home range and core area sizes for each individual in each 3-month time period. Each row represents the home range size (either 95% or 50%) of an individual within a given Year-Month (e.g. January 2024) and the associated environmental data.
Variables
id: Individual's unique ID for each collar deployment (e.g., Accra_1, Accra_2)
id_simple: Individual's simplified name across deployments (e.g., Accra).
isopleth: 'BB95' or 'BB50' to indicate whether measurement represents 95% home range or 50% core area
hr_area: home range area in kilometers squared
monthly_spi: Standard Precipitation Index value representing drought conditions at the monthly scale. Negative values represent dry conditions and positive values represent wet conditions.
threemonth_spi: Standard Precipitation Index value representing drought conditions for the three months prior to the home range measurement. Negative values represent dry conditions and positive values represent wet conditions.
sixmonth_spi: Standard Precipitation Index value representing drought conditions for the six months prior to the home range measurement. Negative values represent dry conditions and positive values represent wet conditions.
prevyear_spi: Standard Precipitation Index value representing drought conditions for the twelve months prior to the home range measurement. Negative values represent dry conditions and positive values represent wet conditions.
date.begin: The first day of the monthly period used for home range estimation
date.end: The last day of the monthly period used for home range estimation
year: Year that home range measurement was collected in (numeric)
YearMon: Year-Month (e.g. January 2024) home range measurement collected in
Month: Month that home range measurement was collected in (numeric)
season: 'Wet' or 'Dry'
label: Unique identifier for this row of data (using year and season (e.g., '2012 Wet 1', '2012 Wet 2', etc.)
Sex: Sex of individual (Male or Female)
Pack: Pack (African wild dogs) or Pride (lions) for social species. Solitary species, cheetahs and leopards, receive NA.
Species: Individual's species (African wild dog, cheetah, leopard, lion)
social_group: Pack (African wild dogs) or Pride (lions) for social species. Solitary species, cheetahs and leopards, receive their individual ID.
Month_categorical: Month that home range measurement was collected in (categorical)
Year_categorical: Year that home range measurement was collected in (categorical)
Code/software
Code is run in R programming language.
Methods
The dataset was collected from GPS collars from four African carnivore species. Fix rates varied between 5 minutes and 3 hours, and were regularized to 3 hour intervals.