European pine marten

Name and taxonomy

Carl Linnaeus described the species in 1758, and the type locality was later fixed at Uppsala in Sweden. The genus Martes holds the martens, and the family Mustelidae holds them with weasels, otters and badgers. GBIF lists other English names: baum marten, sweet marten, forest marten and Eurasian pine marten. In Irish it is cat crainn, the tree cat, and in Croatian it is kuna.

Authors have named thirteen or more subspecies, but nobody has yet revised them properly. One handbook lists eight, including a Minorcan form described in 1987 and Russian forms from the Urals and the north. Some authors have argued that the pine marten, the American marten, the Japanese marten and the sable may all be one species. Genetic work places it closest to the sable, in the subgenus Martes.

Evolution and relatives

Martens are small forest carnivores of the northern hemisphere. The pine marten's closest living relative is thought to be the sable of Siberia. The stone marten, Martes foina, shares much of Europe with it but has a white bib, lighter underfur and a differently shaped upper premolar. A fossil lower tooth from Hunas in Germany closely matches the modern pine marten and differs from the stone marten and the extinct Martes vetus.

The pine marten has 38 teeth, with well-developed shearing and crushing cheek teeth. A long braincase anchors a large jaw muscle, and a flange on the jaw joint stops the lower jaw dislocating when prey struggles. Powerful forelimbs, a long balancing tail and strong claws make it a skilled climber. The red squirrel evolved alongside the marten, which probably explains why it copes with the predator better than the grey squirrel does.

Appearance

The fur is light to dark brown, short and coarse in summer, longer and silkier in winter. The winter coat grows in during September, and the animal moults once a year in spring. The throat and chest carry an irregular patch of cream to orange, and the belly has a greyish tint. The paws are darker than the body, and in winter the soles are fully covered in fur. The nose is black, and the ears are relatively large, rounded and triangular.

The head and body measure 45 to 58 centimetres, and the bushy tail adds 16 to 28. Weight ranges from 0.48 to 1.8 kilograms, with wide variation from place to place. Males outweigh females by 12 to 30%. Young martens gain the adult coat in their first winter. The marten carries an abdominal scent gland and a pair of anal glands.

Habitat and range

The range covers continental Europe from the Atlantic to western Siberia, and from the northern edge of the conifer belt to Asia Minor. It includes the Caucasus, the Elburz Mountains of Iran, and parts of Iraq and Syria. The marten also lives on Mallorca, Minorca, Corsica, Sardinia, Elba and Sicily, though people may have introduced some island populations. GBIF holds occurrence records from 52 countries, a figure that includes zoos and escapes.

The pine marten prefers mature deciduous, mixed and conifer forest, and it is often called a habitat specialist. In Norway it favours spruce forest with large trees and avoids clear-cuts and open ground. A closed canopy is thought to matter because it hides the marten from birds of prey. In Belarus, woodland on clay soil supports more martens than woodland on sand, because it holds more food.

It is not confined to forest. On Minorca, where it has no predators, it lives in scrub and shows no preference for tree cover. In Scotland it uses young plantations, rough grassland, heather moor and field edges, and it runs along stone dykes. In Britain it dens in buildings, trees, other man-made structures and rocks.

Diet and hunting

The pine marten is an omnivore that prefers meat. Small mammals feed it for most of the year, above all voles, mice and squirrels. It also takes birds, eggs, frogs, reptiles, snails, insects and carrion. In western Scotland field voles and birds dominate the diet, with many dung beetles from March to September. Martens foraging along a Scottish loch have eaten crabs, sea urchins and barnacles.

In autumn, fruit such as bramble and rowan berries can make up 30% of the diet in Scotland and on Minorca. In Poland, by contrast, martens may never eat fruit. When voles boom, martens eat far more of them, but their numbers rise only a full year later. They store food in summer and autumn against the lean winter.

The marten hunts in the treetops, racing along thin branches and leaping between crowns after a squirrel. It also searches hollows and cavities for prey, and it forages widely on the forest floor. In Ireland, where martens have spread, grey squirrels retreat and red squirrels recover. Grey squirrels forage on the ground more than reds do, so they probably meet the marten more often.

Behaviour and social life

The pine marten is mainly active at night and at dusk. In Poland, 69% of active time fell at night. On Minorca the night share was 53% in winter and 59% in spring. In spring, male activity peaks in the evening, while in summer and winter it splits into an evening and a pre-dawn bout. A marten may travel 20 to 30 kilometres in a night.

Hollow trees are the favourite nest sites, and each animal keeps several nests in its range. It also rests in old squirrel nests, abandoned bird nests and cracks in rock, and in cold winters it goes underground. Adults live alone, and a male and female stay together only briefly. A male may guard a mated female by defending a range that contains hers.

Home range estimates vary widely: 23 square kilometres for males and 6.5 for females in one source, 2.2 and 1.5 in another. Ranges of the same sex seldom overlap, but a male's range covers those of one or more females. Autumn and winter ranges can be 8 to 54% smaller than spring and summer ranges. Adults tolerate independent sub-adults, often their own young, inside their ranges. In late winter, scent marking, aggression and hormone levels all rise in a so-called false heat that probably drives out last year's young.

Communication and senses

The marten has excellent sight, smell and hearing, and its small rounded ears are highly sensitive. It marks its range with the abdominal and anal scent glands. It also leaves droppings, which are black and twisted, at points around the territory. Scent marking rises sharply in late winter, when social activity peaks.

In the nest, kits twitter to their mother. Adults are mostly quiet, and little else is recorded about their voice. Like other mustelids, it probably uses scent more than sound to find mates and avoid rivals.

Reproduction and life cycle

Mating takes place in July and August. The season lasts 30 to 45 days. In it a female is receptive one to four times, for 1 to 4 days each, at gaps of 6 to 17 days. Pairs usually mate on the ground, and a single mating may run past an hour. The fertilised egg then waits about seven months and implants only in late February or March, when daylight lengthens. Development after implantation takes 30 to 35 days, so the young arrive in late March or April.

A litter holds one to five kits, usually about three, and the female has only four working teats. A newborn weighs about 30 grams and is blind, deaf and toothless. The eyes open at 34 to 38 days, and the kits take solid food at 36 to 45 days. They leave the den at 7 to 8 weeks and can disperse at 12 to 16 weeks. Some young stay in the mother's range through the winter and leave the next spring.

A marten can mate in its first summer at 14 months, but most first breed in their second or third year. In the wild, 3 to 4 years is a typical life, and the record is 11 years. In captivity one animal reached 18.2 years.

Predators and threats

Larger carnivores and birds of prey take martens, especially young ones. The list includes the Eurasian lynx, the wolverine, the red fox, the golden eagle, the eagle owl, the goshawk and the white-tailed eagle. A closed forest canopy is thought to shield it from the birds.

People are the greatest threat. Martens are shot or poisoned during predator control aimed at other species, after taking poultry, or for denning in buildings. Woodland loss and fragmentation remove its habitat. Its fine winter fur has always been in demand, and fur hunting caused a serious decline in the 1970s. In the UK the marten and its dens are fully protected under the Wildlife and Countryside Act 1981.

Population and conservation

The IUCN lists the European pine marten as Least Concern. It remains widespread across Europe, and it has recovered in many areas since the fur-trade decline. Density is about 0.3 to 0.8 animals per square kilometre.

For many years in Britain it survived only in north-west Scotland. By 2012 it had spread into Sutherland, Caithness, Moray, Aberdeenshire, Perthshire and the Central Belt, and to Skye and Mull. In England it was thought extinct until a dropping found in Northumberland in 2010 tested positive. In July 2015 a photographer in Shropshire recorded the first confirmed English sighting in over a century, and juveniles followed in 2019. Martens now breed in the New Forest, and in 2022 one was filmed in London for the first time in a hundred years.

In Wales the Vincent Wildlife Trust released 20 Scottish martens in autumn 2015 and planned 20 more in 2016. Between 2019 and 2021, 35 martens went to the Forest of Dean, where the species was last seen in 1860. By 2023 that population was thought to be approaching 60. In 2024 releases began on Dartmoor and Exmoor. In Ireland the marten is still rare, but it is spreading from the Burren and Killarney into the Midlands.

Relationship with humans

The pine marten keeps away from villages, and no one has ever called it a pest. People have prized its winter pelt for centuries, and medieval Croatians paid their taxes in marten skins. The species has been kept on fur farms, but its slow breeding makes large-scale fur trade impractical.

Gamekeepers persecuted it in Britain until it was almost gone. Today conservation bodies move martens between regions to rebuild lost populations. The Kent and Sussex Wildlife Trusts announced a study in February 2024 into a reintroduction in south-east England. Its taste for grey squirrels has made it an ally of red squirrel conservation in Ireland and Britain.

In culture and myth

Croatia treats the pine marten as a national symbol and stamps it on its euro coins. Before the euro it appeared on the 1, 2, 5 and 25 kuna coins, and kuna itself means marten. In the Irish epic Táin Bó Cúailnge, Queen Meadhbh is said to keep a pet marten on her shoulders. In Celtic tradition the marten stood for cunning and adaptability and was seen as a guardian of the forest.

In Romanian folk belief, martens plait the manes of horses at night, and the owner finds them tangled in the morning. Native American marten clans and kachinas belong to the American marten, a separate species, though websites often mix the two. Spirit-animal blogs list stealth and cleverness as the marten's meanings, but these are probably modern inventions.