Canadian Muskoxen Hit by Double Punch of Novel Diseases and Climate Change

Why It Matters

Muskox declines jeopardize Inuit cultural food sources and signal broader Arctic ecosystem vulnerability to climate‑driven disease emergence.

Key Takeaways

• Novel Erysipelothrix strain killed ~23,000 muskoxen 2009‑14
• Brucellosis prevalence rising in muskoxen since 2015
• Community‑based surveillance links hunters with scientists for early detection
• Arctic warming four times global rate stresses muskox health
• Declines threaten Inuit food security and regional biodiversity

Pulse Analysis

The Canadian Arctic has witnessed a wave of novel pathogens that have decimated muskox populations on Victoria, Banks and Ellesmere islands. Between 2009 and 2014 the Arctic‑specific clone of *Erysipelothrix rhusiopathiae* caused mortality estimates of roughly 23,000 animals, slashing the Banks Island herd from 37,000 to under 14,000. A second health threat, brucellosis, has spread steadily since 2015, with seroprevalence climbing across Victoria Island and adjacent mainland herds. These outbreaks were identified through a community‑based wildlife health surveillance network that pairs Inuit hunters and trappers with university researchers and federal agencies, turning harvested samples into early‑warning data.

At the same time, Arctic warming—nearly four times the global average—has amplified stressors that make muskoxen more vulnerable to disease. Thawing permafrost may release dormant bacteria, while more frequent rain‑on‑snow events create icy crusts that limit access to forage, leading to starvation‑related deaths. Soil and plant chemistry shifts have left animals deficient in trace minerals such as selenium, impairing immune function. Warmer temperatures also enable lungworm species to expand northward, increasing parasite loads that can occupy half of an infected animal’s lung capacity. The convergence of climate‑driven habitat change and infectious disease creates a feedback loop accelerating population declines.

For Inuit communities, muskoxen are more than wildlife; they are a cornerstone of food sovereignty, cultural identity, and local economies. Declining herds force hunters to travel farther, raise costs, and threaten the viability of traditional processing facilities, thereby eroding nutritional security and cultural practices. Policymakers must therefore adopt a One Health framework that integrates climate mitigation, disease monitoring, and Indigenous knowledge to safeguard both the species and the people who depend on it. Strengthening surveillance, funding vaccine research, and protecting critical grazing habitats are essential steps to reverse the current trajectory.