Moose stand as an iconic symbol of Minnesota’s northern wilderness, embodying the spirit of its vast forests and wetlands. As the largest member of the deer family, these animals play an important role in the state’s ecosystem. Understanding their population status is crucial for conservation efforts.
Minnesota’s Moose Population Today
Minnesota’s moose population primarily resides in the northeastern part of the state, a region known as the Arrowhead. The Minnesota Department of Natural Resources (DNR), in collaboration with tribal authorities, conducts annual aerial surveys to estimate their numbers. The 2024 survey estimated approximately 3,470 moose in this primary range, a slight increase from the 3,290 estimated in 2023. While these numbers fluctuate year to year, the population has been considered relatively stable, hovering around 3,700 animals over the past decade. Historically, a smaller population existed in northwestern Minnesota, but that group has seen a drastic decline to fewer than 100 animals. The current focus of population monitoring and conservation efforts is on the larger northeastern herd.
Counting Minnesota’s Moose
Estimating the number of moose in Minnesota involves a detailed aerial survey conducted annually by the DNR, often in partnership with the Fond du Lac Band of Lake Superior Chippewa and the 1854 Treaty Authority. These winter surveys typically occur from mid-January to early February, when snow cover makes moose more visible against the landscape and deciduous trees have lost their leaves. Helicopters are used to fly along predetermined transects within a stratified random sample of 435 plots across the nearly 4-million-acre survey area. Observers in the helicopters identify moose, record their sex and age class (bull, cow, calf), and note their location.
The survey area is divided into low, medium, and high moose density strata, and a selection of these plots, along with specific “habitat” plots, are surveyed each year. While direct counts are made, the final population estimate involves a statistical model that accounts for factors like visibility and moose avoidance of aircraft. This systematic approach provides an overall sense of the population’s status and helps track long-term trends, rather than focusing on precise annual changes.
Understanding Population Changes
Minnesota’s moose population has undergone significant changes, particularly a steep decline from an estimated 8,000 animals in 2009 to its current, more stable levels. Several interconnected factors contribute to these population dynamics. Climate change is a significant concern, as warmer temperatures cause heat stress in moose and can reduce their foraging efficiency. Additionally, milder winters allow for increased survival and proliferation of parasites like winter ticks.
Winter ticks can infest moose by the tens of thousands, leading to severe blood loss, anemia, and weakened conditions, sometimes causing moose to rub off large amounts of their fur, resulting in a “ghost moose” appearance. This can increase their vulnerability to other threats or directly lead to death. Another major factor is brainworm, a parasite carried by white-tailed deer that is harmless to deer but often fatal to moose. Moose become infected when they inadvertently consume gastropods like slugs and snails, which carry brainworm larvae after ingesting deer feces. The parasite damages the moose’s nervous system, leading to neurological issues and death.
Predation, particularly by wolves, also influences moose populations, especially affecting calf survival. While wolves typically prey on the sick or young, a higher wolf population can contribute to a decline in moose numbers. Habitat loss and alteration, whether from human activity or natural forest succession, further impact moose by reducing suitable foraging and cover areas. Ongoing management and conservation efforts aim to understand and mitigate these complex challenges, with a focus on habitat improvement and continued population monitoring.