The European Pine Marten

By Jennifer Heilakka Tosso

Photographs by wildlife photographer Andrew Marshall of Oxfordshire, England

Across the northern United Kingdom lives an intriguing member of the weasel family known for its rarity and elusive nature. The European pine marten (Martes martes) is a mustelid, a member of the weasel family, that is mostly nocturnal and can be rather difficult to find. Light to dark brown in color, with a yellow “bib” spanning their throat and upper chest, individual pine martens can be identified using their specific patterns. They have long, thin bodies with short legs, large bushy tails, and small, rounded, highly sensitive ears. Their claws are semi-retractable, allowing them to lead arboreal lifestyles.

While they are adapted to living in the trees, pine martens are still considered fast runners on the ground. These individuals are highly territorial and will often mark their home range by depositing feces in prominent and easily noticeable places, such as on top of rocks or on open game trails. Each year, pine marten scat can become blue or red in color. Blackberries, bilberries, and rowan berries are responsible for this color change, as they make up the majority of the pine marten’s summer diet. This scat has even been described as smelling like parma violets.

Pine martens have sharp teeth that are adapted for eating small mammals, birds, carrion, frogs, and insects, but will also take berries, eggs, fruit, nuts, and honey if they can find it. This wide range of food choices allows the pine marten to easily find meals and have a healthy store of body fat.

The lifespan of pine martens tends to vary based on where they are found. Pine martens raised in captivity have lived up to 18 years, but their typical lifespan in the wild is drastically less at three to four years of age. They reach sexual maturity around two years old and may begin to breed immediately. During the mating season each summer, they will make a high, shrill cat-like call to attract a suitable mate. Pine martens are relatively solitary creatures, unless a female is caring for a litter or has a home range found within the home range of a territorial male. The mating cycle of female pine martens is extremely interesting. After breeding occurs, the fertilized egg will not enter the uterus for up to seven months. When the fertilized egg enters the uterus, the pine marten will have a litter of one to five kits after a one-month gestation period. In other words, pine martens will have a litter about eight months after breeding, even though they will only carry their litter for one full month. Once the kits are born, they will start to emerge from their den in seven or eight weeks, but it will take around 12-16 weeks for them to leave their den and become fully independent. Females have been known to choose several different types of dens. Some examples include hollow trees, underground burrows, squirrel nests, bird nests, and even rock crevices.

Pine martens prefer woodland habitats and are generally found in the forests of Scotland and Northern Ireland, but may also be seen in coarse grasslands and moorlands. Woodland loss in these areas can cause these mustelids to lose their habitat and struggle to find proper territory. The pine marten was considered extinct in England until recently, when the first sighting was confirmed in the woodlands of Shropshire in 2015. Sightings of adults and juveniles have continued in the area, suggesting that the population is not only recovering, but growing. There is also a small population of pine martens in Wales. In an attempt to boost their numbers and create a sustainable population, the Vincent Wildlife Trust translocated 20 individual pine martens from Scotland to Wales in 2015, with another 35 individuals translocated between 2019 and 2021. As of 2023, the Welsh population was estimated to be around 60 individuals with successful breeding every year.

The greatest threat to the European pine marten is humans. Most problems come from conflict with humans arising from predator control for other species. For example, pine martens are often killed to protect livestock or other animals, causing unnecessary losses to the already struggling population. While the pine marten is prized for their fine fur, the European pine marten and their dens are fully protected under the Wildlife and Countryside Act of 1981 and the Environmental Protection Act of 1990 throughout the United Kingdom. With the continuing efforts of wildlife trusts and government protection, the European pine martens will continue to make a successful comeback in the northern United Kingdom.