. The Canadian field-naturalist. 288 The Canadian Field-Naturalist Vol. 86 Fannin's Color Variation of the Dall Sheep, Ovis Dalli, in the Mentasta Mountains of Eastern Alaska Within the American snow sheep species (Ovis dalli) there are two major color variations — the pure white Dall sheep found throughout much of Alaska and a considerable portion of the Yukon Territory, Canada, and the charcoal-gray Stone sheep found in northern British Columbia. How- ever, in the central and southern parts of the Yukon Territory the demarcation between these color patterns is unclear and many populations sh
. The Canadian field-naturalist. 288 The Canadian Field-Naturalist Vol. 86 Fannin's Color Variation of the Dall Sheep, Ovis Dalli, in the Mentasta Mountains of Eastern Alaska Within the American snow sheep species (Ovis dalli) there are two major color variations — the pure white Dall sheep found throughout much of Alaska and a considerable portion of the Yukon Territory, Canada, and the charcoal-gray Stone sheep found in northern British Columbia. How- ever, in the central and southern parts of the Yukon Territory the demarcation between these color patterns is unclear and many populations share both color variants along with many inter- mediate gradations of the gray-white pattern. These mixed light gray sheep were originally referred to as a separate species — Fannin sheep (Ovis fannini) — but it has long since been recog- nized that these are representatives of a species cline. For references sake their color pattern is still given the name Fannin pattern, or sometimes "saddle-back" sheep, as the gray coloring in its weakest expression is confined to the dorsal shoulder and saddle areas. See Sheldon (1925) for an early discussion of these variants. With the exception of a few black tail specimens of Dall sheep which occur in the Yukon Tanana upland, Alaskan sheep are considered to be pure white. I have confirmed Sheldon's observations that the sheep from the Yukon-Tanana upland do indeed have a high frequency of black tails (this is the standard tail pattern within the Stone sheep variant). I have photographs of a ewe, a yearling which seemed to be attached to her. (possibly her lamb from the previous summer) and a new Iamb. All three individuals have black tails. Other sheep in the White Mountains (a suite of hills within the Yukon-Tanana uplands) were also seen to have black tails or black hairs in the tail. However, there was no indication of any Fannin patterns of gray hairs on the dorsal part of the body. Many Alaskan sheep are stained a dus
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