Rapidly declining fine-scale spatial genetic structure in female red deer

Area of Science:

• Ecology
• Population Genetics
• Conservation Biology

Background:

• Fine-scale genetic structure is increasingly documented in wild vertebrates.
• Ecological factors like population size, dispersal, and mating systems influence genetic structure.
• Temporal and spatial variations in genetic structure due to ecological change are understudied.

Purpose of the Study:

• To investigate temporal variation in fine-scale genetic structure.
• To examine the impact of ecological changes on population genetic structure.
• To analyze genetic structure in a red deer population over a 24-year period.

Main Methods:

• Utilized genetic data and census data from a red deer population on the Isle of Rum, Scotland.
• Assigned adult deer to three subpopulations annually based on census data.
• Calculated Global F(ST) estimates for females and males over the 24-year study period.

Main Results:

• Documented extremely fine-scale spatial genetic structure (<100m) in females, but not males.
• Observed a decrease in Global F(ST) estimates for females over time, indicating a decline in genetic structure.
• Found no significant Global F(ST) estimates for males, suggesting a lack of fine-scale genetic structure.
• Identified an increase in breeding females and a decrease in polygyny, linked to reduced culling early in the study.

Conclusions:

• Increasing female population size and decreasing polygyny likely explain the observed decline in female genetic structure.
• Ecological shifts can drive temporal changes in fine-scale genetic structure within wild populations.
• Findings highlight the dynamic nature of population genetics in response to environmental pressures.