Genomic Analysis Reveals Inbreeding in an Island Population of Alexander Archipelago Wolves

Area of Science:

• Conservation genetics
• Island biogeography
• Wildlife population dynamics

Background:

• Island populations often experience reduced genetic diversity due to limited gene flow.
• Inbreeding depression, a reduction in fitness, is a significant concern for small, isolated populations.
• Alexander Archipelago wolves (Canis lupus ligoni) are a vulnerable subspecies in Southeast Alaska and British Columbia.

Purpose of the Study:

• To assess population structure and inbreeding levels in Alexander Archipelago wolves.
• To investigate the genetic health of wolves on the Prince of Wales Island (POW) complex.
• To inform proactive conservation and management strategies for insular wolf populations.

Main Methods:

• Genomic DNA hybridization capture was employed for 58 wolf individuals sampled from Southeast Alaska (2002-2016).
• Analysis focused on estimating the proportion of the genome in runs of homozygosity (FROH) to quantify inbreeding.
• Comparison of FROH metrics, including long runs (≥10 Mb), was conducted across different wolf populations.

Main Results:

• Wolves on the Prince of Wales Island complex (POW) exhibited the highest levels of inbreeding compared to other Southeast Alaskan populations.
• POW wolves showed a greater number of long runs of homozygosity, indicating recent common ancestry.
• These genetic patterns suggest a smaller historical population size for POW wolves.

Conclusions:

• The extent of inbreeding in POW wolves is comparable to that of the Isle Royale wolf population, known for severe inbreeding depression.
• Genomic data effectively infers individual inbreeding, crucial for managing small, isolated wildlife populations.
• Proactive management, including harvest quotas and habitat considerations, is essential for the sustainability of vulnerable island wolf populations.