Icelandic sheep breeds
The top photo show the breed Leader sheep, photo by Ragnar Thorsteinsson.
Native name: Íslenskt sauðfé.
English name: Icelandi sheep.
Weight: Average 63kg (ewes) 95kg (rams).
Wither height: 78 cm (rams), 68 cm (ewes).
Appearance and colour: Short tailed, medium-built. Short-legged and the face and legs are free of wool. Can be both horned and polled (most sheep are horned). Mainly white, but shades of black, grey and brown can occur.
Breed type: Meat and wool production.
Number of offspring: 1-3 lambs per ewe.
Birthweight: 4 kg.
Number of sheep in Iceland (2023): 345,000.
Not at Risk – Vulnerable – Enangered – Critically Endangered – Extinct
Native name: Íslenskt forystufé
English name: Leader sheep
Weight: 80 kg (rams), 55 kg (ewes).
Wither height: 80 cm (rams), 70 cm (ewes).
Appearance and colour: Can be both horned and polled. Long legs and slim body. The main colours are black and grey.
Number of offspring: 1-2 lambs per ewe.
Birthweight: 3,5 kg
Number of sheep 2023: 3,500
Not at Risk – Vulnerable – Enangered – Critically Endangered – Extinct
Short introduction
Sheep play a central role in Icelandic tradition and rural life. After lambing in May, flocks are released to graze freely across the country’s vast mountain pastures. This seasonal grazing practice is deeply rooted in Icelandic culture and culminates in one of the nation’s oldest traditions: the autumn sheep roundup known as “Réttir”. Réttir typically takes place in September and can span several days, as farmers and volunteers gather sheep from the highlands. The final day of the roundup is a festive occasion, where communities come together to sort the sheep, share stories, and celebrate. Iceland is home to two unique native sheep breeds: The Icelandic sheep and the Leader sheep.
Breed origin and development
The Icelandic sheep has a long history tracing back to the country’s early settlement period, between 874 and 930 AD. The first sheep were brought to Iceland by settlers and gradually mixed over time, forming the breed we see today.
Because breeding of the Icelandic sheep has focused more on performance traits than on appearance, Icelandic sheep show a wide variety of colours and horn types. However, the population is broadly divided into two phenotypic groups: approximately 70% are horned, while 30% are polled. The Icelandic sheep is also known for its high reproductive capacity - around 80% of ewes give birth to twins, and the average litter size is just over 1.8 lambs. A gene associated with increased litter size has been identified in the population; ewes carrying this gene can produce up to six lambs (Davis, 2005).
Over time, temporary breeding lines have emerged within the breed. One of the most notable is Leader sheep, a group long recognised for its intelligence and strong sense of direction. These sheep were traditionally valued for their ability to guide flocks safely through difficult terrain. Due to its unique behavioural traits and genetic distinctness, the Leader sheep was formally recognised as a breed of its own in 2017. Both the Icelandic sheep and the Leader sheep belong to the group of sheep known as North European short-tailed sheep and share a common ancestry with various native breeds from Scandinavia.
Breeding and conservation
The overreaching goal of Icelandic sheep breeding has always been to develop robust and healthy animals. Because of this, the breeding goal has been relatively broad. The focus has traditionally been on improving lamb production, which includes traits such as fertility, body shape, growth rate and milk yield in ewes. Over time, selecting for better carcass quality has changed the conformation of the Icelandic sheep.
Organised breeding began in the early 20th century with coordinated judging of mature rams at ram shows. Live-animal evaluation remains a cornerstone of the programme, although in recent efforts the focus has been put on lambs to help farmers choose the best animals to keep for breeding. Performance recording was introduced in the late 1930s and expanded rapidly. Today, over 90% of Icelandic sheep are registered in FJÁRVÍS, a national online database that stores pedigree and performance information. These records are used to calculate breeding values for key traits, guiding farmers to select the best sheep for future breeding. The Farmers’ Association of Iceland oversees this national breeding programme.
In the past, foreign sheep breeds were imported to improve local genetics, but this led to disease outbreaks of scrapie and mass culling. The last documented import occurred in 1933, and since then, Iceland has kept its sheep population closed to prevent the introduction of new diseases into the population. Strict movement restrictions between regions in Iceland have also been implemented as a measure against disease spread. Because of this, artificial insemination has become an increasingly useful tool in breeding to promote genetic diversity. However, most farmers prefer natural breeding, using rams within their region.
Scrapie has been epidemic in Iceland for a long time, causing problems for sheep farmers. The number of scrapie cases has declined drastically since the peak of the epidemic in 1980s, but there have been a few cases detected in recent years, primarily in the northern regions. Culling has been the main approach to fight this disease. The detection of the protective ARR allele in some areas and T137 protective polymorphism has made it possible to implement a new approach: Breeding for scrapie resistance in Icelandic sheep. Subsequently, the Ministry of Agriculture has issued a national plan to incorporate protective genotypes into the sheep breeding goal, with the emphasis on protecting genetic diversity (June 2025).
The Genetic Resource Committee is responsible for the implementation and monitoring efforts to maintain and conserve genetic diversity in Icelandic livestock. The Icelandic sheep and the Leader sheep are truly unique breeds, valued for their own different characteristics, as well as their deep cultural roots. With a large and healthy population, the Icelandic sheep breed is considered sustainable. On the other end, the population of Leader sheep is small, and more vulnerable to extinction. Therefore, continuous monitoring of these breeds is essential, as it enables the detection of changes in genetic diversity and inbreeding levels allowing for timely interventions to support sustainable population management.
Characterisation in research
Breed characterisation research plays a vital role in conserving animal genetic resources. It helps identify unique traits that may be valuable for securing future food production. A comprehensive review by Kierkegaard et al. (2020) identified eight characterisation studies on Icelandic sheep conducted up to 2019. Most studies focused on molecular diversity within and between breeds (Tapio et al., 2010; Chessa et al., 2009; Tapio et al., 2005), while others examined phenotypic traits (von Holstein and Makarewicz, 2016), genetic variability (Adalsteinsson, 1975), and socio-cultural significance (Dýrmundsson and Niżnikowski, 2010). Additional studies have explored genetic variation in woolskin quality (Eythórsdóttir, 1999), heritability of important traits such as longevity (Hlinadóttir, 2023), and genetic variants linked to horn phenotypes (Simon et al., 2024).
Kierkegaard et al. (2020) also reviewed a phenotypic characterisation study of the Leader sheep (Dýrmundsson, 2002), and further projects have investigated their behavioural traits and distribution across Iceland (Jónmundsson and Dýrmundsson, 2019). Key genetic parameters, including inbreeding and effective population size, have been calculated to assess the breed’s genetic status following the mid-20th-century bottleneck. Findings indicate that inbreeding has been successfully managed (Jónmundsson et al., 2015).
Fun facts
If you wear a sweater made of wool from leader sheep – you will always find the way home.
Read more about our other native breeds
-
Nordland/Lyngen Horse
The first known and documented exhibition where this breed participated, was in 1898 at Lyngseidet in Troms. In the 1930s, organized breeding of Nordland/Lyngen horses started.
-
The Nordic brown bee
Honey bees are threatened by intensive agriculture, habitat loss and climate changes worldwide and are important to conserve, not only due to their honey production but also due to their pollination services.
-
Finnish Landrace Chicken
In 1974, the agricultural advisory agency collaborated with Seiskari and published a call to find remains of the Finnish landrace chicken. As a result, one flock was found in South-East Finland. This family line was named after its geographical location as “Savitaipaleenkanta”.
