There are many physical features of the Herdwick breed that strongly suggest a very considerable genetic distance from other native breeds of the UK.

The fleece colouring is highly distinctive, as is the fact that the colour changes strikingly during the development and ageing of the animal. The coat of lambs is jet black, even though their skin is white. As the lamb ages, gradually the face, then the head and ears and the legs become white. By six months, the youngsters have frost white heads and legs and the fleece has developed into a rich dark chocolate colour that is maintained until clipping. On shearing off this young fleece, the new coat is dark slate grey. For some sheep, the fleeces thereafter remain the dark colour – for others the fleeces progressively become a paler grey as the sheep ages. Sometimes the very first fleece of the shearling can be pale grey and this can remain or become near white in subsequent years.

Historically, Herdwicks have been maintained in vast fell flocks composed of many thousand animals. Today there continue to be some large fell flocks, but the numbers of these flocks are decreasing – not least as a result of the short-sightedness of organisations that do not understand how to manage the biodiversity of the fells by appropiate grazing and are enforcing the removal of sheep.

Today, Herdwick sheep can still be seen in the countryside of the Lakes, but overall they are no longer the abundant breed that can be seen with more and more farmers coming off the fells and turning to other sheep breeds, or cross-breeding their Herdwick ewes with tups of other breeds. In modern times, the adaptation of the breed to low input extensive farming systems is rarely welcomed by a sheep industry that prefers lambs rapidly fattened by supplementary feeding.

Despite the loss in numbers and the increase of cross-breeding there remain some exceptional pure bred Herdwick flocks tended by breeders highly committed to conserving the very best qualities of the breed.