Range-wide climate risk and adaptive potential in a cold-water fish species

Area of Science:

• Ecology and evolutionary biology
• Climate change science
• Genomics and bioinformatics

Background:

• Climate change poses extinction risks to coldwater species like brook trout.
• Understanding local adaptation is crucial for predicting species' responses to warming.
• Brook trout populations are experiencing extirpations due to rising temperatures.

Purpose of the Study:

• To identify molecular mechanisms of local adaptation to heat stress in brook trout.
• To assess the vulnerability of brook trout populations to climate change.
• To inform conservation strategies, including assisted gene flow, for climate resilience.

Main Methods:

• Integration of experimental approaches, omics (genomics, transcriptomics), and climate change modeling.
• Genomic variation analysis across the native range to detect local adaptation.
• Experimental validation of gene expression responses to thermal stress.

Main Results:

• Genomic variation correlates with thermal conditions, indicating local adaptation in brook trout.
• Specific genetic variants linked to gene expression changes under thermal stress were identified.
• Climate projections show southern populations are most vulnerable to extirpation; mid-range populations are suitable for assisted gene flow.

Conclusions:

• Genomic insights are vital for managing brook trout populations under climate change.
• Southern brook trout populations require urgent conservation attention due to high vulnerability.
• Assisted gene flow using resilient populations can enhance the adaptive capacity of threatened brook trout.