Colour and Coat Pattern in Soay sheep


Dark Phase, Light Phase, a Definition
Soay sheep on St. Kilda and also those on the mainland, have a wide variety of fleece colours which cause much confusion when putting a name to a colour type.  Island Survivors was the first book to give descriptions of the various colours and it is the resource most subsequent literature refers to.  Our comments here are based on those descriptions and our own personal observations of sheep on St. Kilda.

Dark and Light Phase, wild pattern ewes resting on Ruaival 

Dark and light  phase Soay with a variety of shades resting mid-day  on Ruaival

There are two basic colours of Soay; dark phase and light phase and two basic coat patterns within each of these colours, "mouflon or wild” and "self".  Most of the sheep on St. Kilda are dark and about one third are light. However, this proportion seems to be changing over time.  The majority of both dark and light animals have a "mouflon" pattern of markings named such because of its similarity  to wild mouflon sheep, a probable ancestor.   It is also referred to as "wild" because of the light belly which is found in wild sheep. Soay are the only domestic sheep to retain this primitive trait.  This contrasting pale colour is also shown on the face where the area surrounding the eyes, the corner of the mouth and throat are some shade of white.  The belly and rump areas and the inside of the legs often match this light marking.  A very small portion are referred to "self colour " these animals have no contrasting pale fleece. 

                                                                               Dark and light phase sheep facing each other
Dark and light phase sheep facing each other


Dark Phase  mouflon/wild coat pattern

Most dark phase sheep have the "mouflon" or "wild"  pattern but these marks vary a great deal with individual animals. Some have a distinct demarcation line between a very  dark brown main fleece of the body and the very light markings of the face, legs and rump, but this is not always the case, with some the "wild "markings are almost obscured . Some dark phase sheep also have a much lighter brown coat ( these animals very likely have one light phase parent) . 

  Dark mouflon/wild marking, Soay ram Hirta

Distinctly marked dark mouflon/wild Soay ram, Hirta

dark phase rams 

Two dark phase mouflon/wild Soay rams, Hirta

various shades of dark phase 

A variety of shades of dark phase rams Hirta

Dark phase self coat pattern
The sheep with this fleece type are described as "self black" and/or "self dark or self dark brown" They have no contrasting markings on their faces, body  or belly.  All such sheep are born as uniformly  black or dark chocolate brown lambs and either remain dark or become much paler- "light phase in fact." (Jewell 1974)

dark phase self ewe Hirta

Dark phase self ewe,  Hirta 

Light phase mouflon/wild coat pattern
The sheep with this colouration are a much lighter version of dark phase. The main body colour is a light fawn brown color with the same lighter markings around the eyes, mouth, throat, belly, rump and inside the legs as dark phase animals The fawn body  colour varies with individuals with some almost a biscuit colour to others which are a much darker tan.  These variations have caused many different names to be used for the base colour of light phase animals. They are frequently also called "Blond" or "Tan".   

light phase wild/mouflon pattern ram Hirta

 Light phase mouflon/wild Soay ram, Hirta

very pale light phase Soay ewes

 Very light light phase mouflon/wild ewes, Hirta


light phase Soay mix of colours

Light phase mouflon/wild pattern, dark phase lamb next to its mother (center), Hirta


Light phase self coat pattern
The lambs that will mature to be this colouration are usually born with a uniform dark russet chocolate colour. As they grow, their fleeces becomes lighter but the face and legs usually stay darker than the rest of the body. The contrasting eye, mouth, throat, belly and rump markings are absent.                                 

light phase Soay ewe Hirta

Light phase self ewe, Hirta

Non typical colourations
The majority of the sheep on St. Kilda have the fleece colouration's described above, but there are a very few that are different. These animals stand out and are easy to distinguish. In some cases the differences are small but very occasionally a real oddity occurs, primarily white in an unusual area of the fleece.  White on the poll of the head is the most common, however, white on the face which can cover the whole head and half white legs are seen.  The extreme example is the piebald with large white patches on the back and flank. While very rare, they do occur.

non typical coloration light phase white marking 

Light phase mouflon/wild pattern ewe with white blaze (her light phase self lamb stands behind her), Hirta

Non typical coloration 

Dark self ram lamb with unusual white markings,  Hirta

 non typical coloration Soay ewe Hirta

Dark phase ewe with white mottled area on her body, Hirta              Paddy Zakaria photo