Genetic variation and hybridization determine the outcomes of conservation reintroductions
Data files
Oct 08, 2025 version files 15.16 MB
Abstract
The preservation of genetic variation is fundamental in biodiversity conservation, yet its importance for population viability remains contentious. Mixed-source reintroductions, where individuals are translocated into a single vacant habitat from multiple genetically divergent and often depauperate populations, provide an opportunity to evaluate how genetic variation and hybridization influence individual- and relative population fitness. Population genetic theory predicts that individuals with higher genetic variation and hybrids among populations should have higher fitness. We tested these hypotheses by analyzing individual and population-scale data for translocated westslope cutthroat trout (Oncorhynchus clarkii lewisi) and their offspring in four mixed-source reintroductions. We observed more hybrid and fewer nonhybrid offspring than expected across four independent mixed-source reintroductions. We also found clear evidence that heterozygosity predicted individual reproductive- and relative population fitness. Overall, we found a strong, positive relationship between genetic variation, hybridization, and transplant fitness, emphasizing the importance of genetic variation and population mixing in conservation.
https://doi.org/10.5061/dryad.sxksn0380
Description of the data and file structure
These data were collected from several westslope cutthroat trout populations in southwest Montana to better understand native species reintroduction outcomes. Data contain both demographic (length, weight, site collected, population of origin, year sampled, etc.) and genetic data for individuals sampled throughout this study.
Files and variables
File: SF_Greenhorn_RAD_Data_NOT_FILTERED.csv
Description: RAD capture sequencing data (genetic data) for donor fish translocated into SF Greenhorn Creek and their offspring sampled following translocation events. This is the unfiltered dataset, meaning no genetic filtering steps (described in the supplemental) have been performed with this dataset. This genetic data set is separate from the other genetic dataset because SF Greenhorn Creek fish analyses required higher resolution genetic data (requiring more markers for parentage analyses). These data were used for individual-level genetic analyses.
Variables
- ID: Individual identifier for each individual fish. Individuals are offspring sampled within the recipient (reintroduction) stream or adults sampled and translocated from a donor stream.
- Gen_ID: Additional individual identifier for each individual fish associated with genetic data. NA indicates no genetic ID associated with that individual due to the individual genetic data being duplicated.
- Population: Stream of origin for each individual fish. NA indicates no population associated with that individual due to the individual genetic data being duplicated.
- Site: Location within each stream that an individual was sampled from. NA indicates no site associated with that individual due to the individual genetic data being duplicated or because the individual was a donor (possible parent) that was translocated to a recipient stream.
- Omy01_XXXXXXX: The genotype at a specific locus for each individual fish. NA indicates no genotype detected for that individual at that locus.
File: GTseq_Genotype_Data_Reintroduction_Streams_NOT_FILTERED.csv
Description: GTseq sequencing data (genetic data) for donor fish translocated into SF Greenhorn, NF Greenhorn, Peet, and Ruby Creeks and their offspring sampled following translocation events. This is the unfiltered dataset, meaning no genetic filtering steps (described in the supplemental) have been performed with this dataset. This genetic data is separate from the other genetic dataset because SF Greenhorn Creek fish analyses required higher resolution genetic data (requiring more markers for parentage analyses). These data were used for population- and individual-level genetic analyses.
Variables
- IndID: Individual identifier for each individual fish. Individuals are offspring sampled within the recipient (reintroduction) stream or adults sampled and translocated from a donor stream.
- Population: Stream of origin for each individual fish. NA indicates no population associated with that individual due to the individual genetic data being duplicated.
- Plate: The plate number where the extracted DNA exists.
- Well: The well within each plate where the extracted DNA exists.
- Site: Location within each stream that an individual was sampled from. NA indicates no site associated with that individual due to the individual genetic data being duplicated or because the individual was a donor (possible parent) that was translocated to a recipient stream.
- Year: The year that samples were collected from the individual fish.
- Ocl_XXXXX_XX: The genotype at a specific locus for each individual fish. NA indicates no genotype detected for that individual at that locus.
File: NF_and_SF_Greenhorn_Translocated_Parents_demographic_data.csv
Description: Biological data for all donor fish that were translocated to a recipient (reintroduction) stream.
Variables
- Genetic ID: Individual identifier (associated with genetic data) for each individual adult fish that was translocated to a recipient (reintroduction) stream.
- Year: The year that samples were collected from the individual fish.
- Stream: Stream of origin for each individual fish.
- Length: The total length in millimeters of each individual fish.
File: NF_and_SF_Greenhorn_reintroduction_demographic_data.csv
Description: Biological data for all offspring sampled in reintroduction streams.
Variables
- Field_ID: Individual identifier for each individual fish sampled in SF Greenhorn and NF Greenhorn Creeks.
- Site: Location within NF Greenhorn and SF Greenhorn Creeks where individual fish were sampled.
- Reintroduction: Stream that fish were captured in.
- Pass: The iteration that a site was sampled (i.e., a pass of 1 was the first sampling effort of that section). "B" and "A" represent whether fish were sampled above or below a given site.
- Length: The total length in millimeters of each individual fish.
- Weight : The total weight in grams of each individual fish.
- Date: The date that each fish was sampled.
- Year: The year that each fish was sampled.
File: README.md
Description:
Code/software
Microsoft Excel can be used to view all datasets provided.
R was used to analyze all data provided.