Wolves Are Expanding in Agricultural Denmark. Why Not New England?
A wolf pauses in crossing a tilled field in Jutland, Denmark. Photo © Eskil J. Nielsen-Ferreira, courtesy of Wolf Atlas, Aarhus Natural History Museum Photo Gallery
Occasionally in meeting a new person, opening a fresh book, or traveling, one experiences completely new thoughts or identifies novel solutions to old problems. Such was my experience on returning this summer to Denmark, a country that I have grown to love over a couple dozen visits since I first traveled there in 1972 with my girlfriend (now wife) to visit her grandmother. This summer we headed to westernmost Jutland, the mainland portion of this island-rich country, to explore the oldest national park and largest wilderness in this country that is roughly the size of Massachusetts and Connecticut combined. At 60,000 acres, Thy National Park is small by American standards, but its dune-covered landscape of heathland, endless beaches, and scattered villages offers a spectacular setting on the powerful North Sea. Historically, the once-forested terrain was progressively cleared beginning in Neolithic times (5,000 years ago) and now contains striking legacies: Bronze Age burial mounds that range up to 15 feet in height and 40 feet across; conifer plantations established beginning in the mid-nineteenth century to tame the sand from burying villages; remnant bunkers from German occupation; distant views of some of the 6,000 immense wind turbines that energize this progressive country; and the heathland itself. Beyond the park lies one of the most productive cultivated landscapes of this agriculturally rich nation.
I was intent on exploring the natural history of this landscape, and my pre-trip reading had revealed that a wolf migrant from Germany had died in the park in 2012, one of the first wolves in Denmark since the eighteenth century. Noting that fact, I joked with the editorial board of From the Ground Up that I would report back on top carnivores in what is one of Europe’s tamest and most open landscapes.
The joke was on me. Once I connected with research from Aarhus University and the Natural History Museum in Aarhus, I discovered a remarkable fact. Wolves are becoming well established across mainland Denmark, are reproducing, and are expected to increase substantially. Through ongoing immigration from Germany and native breeding since 2019, the population now stands around 78 animals, comprising at least eight breeding pairs, six packs, 23–28 wandering individuals, and 35 pups born in the country in 2024. What makes this phenomenon so astonishing is how ill suited this countryside appears for wolves. That is, unsuited by conventional thinking, the kind that suggests that moose could not adapt to southern New England; that bears would not situate around the cities of western Massachusetts; or that coyotes, beavers, and fishers would not saturate these same landscapes. As I explored the dynamics of wolves in Denmark, I reflected on the ongoing return of native wildlife to the much more heavily forested landscape of New England and asked—Why not here?
The open heathland and dune landscape of Thy National Park in northwestern Jutland, described in park literature as the largest wilderness in Denmark. Across the country, grazing animals, such as the horses pictured here, are enclosed on conservation lands with permanent or portable fencing. This activity maintains the open landscape and supports biodiversity that has developed over many thousands of years of deforestation and grazing by cattle, horses, sheep, and goats. Photo © David Foster
The Cultural Landscape Setting for Wolves
Comprising two-thirds (11,500 square miles) of Denmark, Jutland forms an open and flat to rolling landscape of industrial farms where production livestock (pigs, cows, and mink raised for fur) are confined in low barns surrounded by expansive fields of grains, mustard seed, potatoes, hay, and corn. This open farmland covers 60 percent of the land. Scattered woodlots of oak, beech, and conifers occupy less than 15 percent of the peninsula, while horses, sheep, and cows graze the remainder—scenic pastures and heathlands on less fertile, dry, wet, and conservation lands. The closest New England analog to this scene is the Champlain Valley of Vermont, an apt comparison, as the large Danish lakes suffer—along with Lake Champlain—from siltation and severe agricultural pollution. Immense wind turbines appear on every horizon. Beautiful villages and towns and more obtrusive industrial and commercial centers are scattered throughout. Strikingly, sprawl is absent: strict zoning neatly separates developed areas (10 percent of the land) from the intervening countryside of intact farm and forest. The population density (85 people per square kilometer) sits between that of northern and southern New England (New Hampshire at 58 per square kilometer; Connecticut at 288 per square kilometer), and the road density is similar to, but more uniform than, that of Massachusetts.
The productive industrial agricultural landscape of northwestern Jutland. Immense farms produce pigs, dairy and beef products, mink for fur, and wood for timber and bioenergy. Expansive tilled areas provide grains, hay, corn, and other food for barn-raised animals and human consumption, and are interrupted by wooded fencerows and ubiquitous wind turbines. Photo © David Foster
The Arrival and Spread of Wolves
Denmark is a centrally planned country where few changes are inadvertent. Government regulations and studies abound to guide development and land cover change, as well as recent conservation efforts including planned reforestation, new national parks, and the reintroduction of native species like beaver. But the establishment of wolves in this domesticated country was as completely unplanned as the natural reforestation of New England in the nineteenth century. Across the European Union, rural depopulation, reforestation, and legal protection for wolves have allowed the species to spread widely, reaching every member country except the island states (e.g., Iceland, Ireland, Cyprus) and exceeding 13,000 individuals. Though unplanned, the migration to Denmark was inevitable. Nature accomplishes remarkable things when left alone.
The earliest wolf report occurred in 2007, but the 2012 death in Thy provided the first DNA confirmation. With that discovery a national research and monitoring program was established at Aarhus University and the Aarhus Natural History Museum to compile camera trap data, sightings, genetic analyses, and research. This comprehensive database reveals that arrivals from more heavily forested Germany built the Danish population until 2020, when native reproduction exceeded immigration, and wolves began crossing the Danish-German border in both directions.
Distribution of the grey wolf populations in Europe. Courtesy of the 2019 European Union review.
Directions of gene flow among European wolf populations. Green: permanent populations; dark grey: sporadic occurrence (primarily Fennoscandia); red: confirmed dispersal between and within wolf populations. Note that the small populations in Belgium, the Netherlands, and northern Germany are not fully represented in these 2018 data. Courtesy of the 2019 European Union review.
Survival
“Few animals are as adaptable as the wolf, which boasts one of the widest distributions of any land carnivore.”
Despite widespread misperceptions that wolves require expansive uninhabited terrain, they are broad generalists in habitat and diet. Given adequate prey—largely deer, moose, and boar in Europe—they flexibly inhabit a range of forest and agricultural terrain. In Denmark the wolves concentrate on roe deer, which are small (35-70 pounds) and abundant (some 300,000 nationally), and red deer, a close relative of elk that can exceed 400 pounds and has a population of about 24,000 in the country. Humans pose the main threat to wolves, which have adapted successfully to minimize contact. Individuals avoid roads and areas of human activity. Mating pairs raise pups in more remote areas of forest and heath cover. Camera trap studies reveal that the Danish animals have developed an extreme nocturnal schedule. Through most of the year they avoid humans by moving primarily during the dark hours. During the extremely long days of summer, they are most active around dusk.
Seasonal patterns of daily activity of humans, red deer, and wolves in Jutland, Denmark. In this open agricultural landscape, wolves have adopted an extreme nocturnal pattern of movement that minimizes interactions with people and facilitates hunting of native prey. Only in the extremely long summer days (17–18 hours) are wolves active during daylight hours. Diagram from P. Sunde et al. 2024, Wildlife Biology
Across Europe illegal hunting is the major source of wolf mortality, accounting for more than half of the deaths in Sweden, Norway, and Finland. This appears to be the case in Denmark, as well, where the average wolf lifespan remains less than three years. Two or three animals have been killed on roads, but most have simply disappeared. The filmed shooting of a one-year-old female wolf led to the conviction of a 67-year-old man for violating the country’s hunting act and may deter similar incidents. Hunters comprise 3.3 percent of the population, a level lying between that of southern and northern New England (1 percent in Massachusetts and Connecticut; 12 percent in Vermont and Maine).
Distribution of wolf sightings in Denmark from 2012 to August 2024 based on a 10x10 km grid and database maintained by the Danish Wolf Atlas Project at the Natural History Museum in Aarhus. Wolves are confined to the mainland peninsula of Jutland, which is connected to Germany, and have not yet migrated to the major islands. Copenhagen is situated on the largest island to the east, Sjaelland, where suitable wolf habitat is provided by extensive forests and a large deer population. Courtesy of Danish Wolf Atlas Project.
Wolf habitat suitability for Jutland, the mainland portion of Denmark that currently supports wolves. The darker the blue color, the more likely that wolves will establish territory in that square. Squares framed in red are part of past or present territories. Yellow stars indicate the occurrence of pairs/couples, and white stars territory with lone wolves in 2023. The black line shows the border between the Atlantic and the continental biogeographical region. The Atlantic region is flatter terrain with more productive farms and fewer people. Courtesy of Aarhus University National Center for Manufacture and Energy.
Human Reception and Conflicts
“Nature accomplishes remarkable things when left alone.”
Public reactions to the arrival and growth of the wolf population range from concern to fascination, fueling a vigorous debate on management. Attitudes break down along familiar lines existing across Europe and North America. The strongest support is found among urban populations and conservationists, with the latter citing the potential benefits for biodiversity and ecosystem health, the health of prey species, and local economies from ecotourism. In contrast, 80 percent of Danish landowners would like fewer wolves, and 60 percent prefer illegal measures of control over regulated approaches. This group is concerned about negative economic impacts, competition with hunters for game, safety of humans and domestic animals, and lack of trust in government authorities.
Although low initially, the number of livestock incidents has increased as the wolf population has grown and expanded into new areas. Attacks climbed from 16 in 2021 to 57 in 2023. A detailed study of wolf DNA from attacked livestock revealed that these attacks are strongly associated with wolves that are dispersing across new terrain. Settled wolves establish territories in areas with less human activity and feed primarily on native wildlife, whereas dispersing wolves often move through agricultural regions with more sheep and fewer natural prey. These results show that livestock losses are concentrated in a very limited part (16 percent) of the region, and they offer the promise for focused efforts to reduce livestock depredation overall.
Denmark is drawing from experience elsewhere to improve public attitudes and reduce conflicts by prioritizing communication and proactively responding to livestock losses. Compensation for farmers’ losses softens public and landowner animosity, but European experience indicates that it does little to alter farming practices. One practice that can help reduce attacks is the use of taller electrified mesh fencing. Authorities are promoting this practice with subsidies. Other deterrent techniques include guard dogs, nighttime enclosure of livestock, and careful management of grazing and birthing.
“The wolf is a predator to deer—if you can have deer, you can have wolves…they will be fine in these human-dominated landscapes. In Denmark there’s no reason wolves can’t thrive. But the question has to be asked, are people going to accept the wolves?”
Additional efforts seek to keep wolves wild through public education, facilitating safe tourist sightings and photography, prohibiting feeding, and controlling trash. Wolves that become habituated to humans may be harassed, and animals that feed repeatedly on livestock may be killed. An overriding interest is to maintain viable habitat and robust native prey populations.
Prognosis for the Danish Wolf
The Jutland wolf population needs major growth to be genetically viable and secure against natural and human impacts. Habitat suitability mapping identifies considerable potential for expansion. Researchers estimate that the Danish mainland could support as many as 200 animals. There appears to be broad consensus amongst biologists that the minimum population for long-term genetic viability is about 500 individuals. Therefore, the Danish sub-population will continue to rely on sustained immigration from Central Europe.
One frequently cited finding is that population growth will require mortality to remain below 35 percent annually. Illegal hunting remains the major concern. Though the European Union has offered protection for wolves under the Bern Convention since 1979 and Habitats Directive since 1992, regulation and enforcement rely on individual countries. The 2024 high court confirmation of the first conviction sets an important precedent for Denmark in this effort.
Announced in 2024, Denmark’s Green Tripartite Agreement, a major new public and private conservation program, will increase the amount of forest in the country to address climate change, reduce pollution of inland and coastal waters, and enhance native biodiversity. This well-funded effort will establish many new national parks and should have a strongly beneficial effect on the wolf population.
The broad dynamics of forest cover and distinctive wildlife since the time of European arrival, when expansive old-growth forests dominated a landscape lightly lived on by a thriving Indigenous population. Deforestation for agriculture, intensive harvesting of remaining forests, and extensive and unregulated hunting and trapping drove the decline and extirpation of many native species and allowed the expansion and arrival of many species that thrived in open agricultural landscapes. Forest recovery with a broad decline in agriculture, coupled with hunting regulation and purposeful wildlife reintroductions, allowed many native species to recover and led to a corresponding decline in open-land species. Though 80 percent of New England is now forested, the largest predators—wolves and cougar—remain absent. From Wildlife dynamics in the changing New England landscape
Why Not New England?
The historical recovery of New England’s forests and wildlife is prominently cited nationally and internationally as one of the world’s great environmental stories. Forests have doubled in the last century and many native species are recovering, including bear, bobcat, fisher, osprey, eagle, moose, and beaver. Nonetheless, old-growth forests remain rare, truly wild forests occupy less than 4% of the landscape, and the two top predators—cougar and wolf—remain absent. Following a wave of optimism in the 1990s spearheaded through efforts by RESTORE, National Wildlife Federation, and other groups and reported in the Northern Forest Forum, public energy behind and attitudes concerning wolf reintroductions in New England have vacillated. Occasional individual wolves migrate to the region but are killed because they are mistaken for coyotes, which are hunted extensively.
“The Northern Forest Ecosystem, a 26 million acre forested area from the Adirondack Mountains of New York east through most of Maine, contains suitable gray wolf habitat and lies within the historical range of the gray wolf.”
The two greatest obstacles to successful establishment of wolves through migration or introduction remain a lack of support by state and federal agencies on the one hand, and public misunderstanding of wolf behavior on the other. Most opponents cite concerns for small children and pets, potential impacts on farmers, and the general unsuitability of the region as wolf habitat. Experience from the domesticated landscape of Denmark, elsewhere in Europe, and in Minnesota—where more than 2,700 wolves thrive across half of the state—provide an important alternative view. Wolves, like their smaller relatives the coyotes, pose much less risk than perceived, are highly adaptable, and could readily survive in broad parts of the New England landscape. Despite a six-month hunting season, the coyote population in Massachusetts exceeds 12,000 animals and occupies every town on the mainland rather imperceptibly. Wolves would reduce that population, complement it ecologically, and help to advance the ecological recovery of our landscape.
A horse keeps watch as a wolf crosses an open field in Jutland, Denmark. Photo © Niels Anders Bak, courtesy of Wolf Atlas, Aarhus Natural History Museum Photo Gallery
David Foster is an ecologist, Director Emeritus of the Harvard Forest, and President Emeritus of the Highstead Foundation. He co-founded the Wildlands and Woodlands Initiative in 2005 and was lead writer of Wildlands in New England: Past, Present, and Future in 2023. David has written and edited books including Thoreau’s Country: Journey Through a Transformed Landscape; Forests in Time: The Environmental Consequences of 1,000 Years of Change in New England; Hemlock: A Forest Giant on the Edge; and A Meeting of Land and Sea: The Nature and Future of Martha’s Vineyard.
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