3
COMMUNICATIONS FROM THE MAMMAL SOCIETY-NO. 74 387 Debbie Perkins and Chris Chimimba (Transvaal Museum) arranged for access to the mammal collection. John R. Speakman provided valuable criticism of an earlier draft. Thanks are also due to John D. Skinner and Nigel Bennett. Financial support was provided by the Foundation for Research Development (South Africa) and the Bob Blundell Memorial Scholarship. REFERENCES Clutton-Brock, T. H. &Harvey, P. H. (1983). The functional significance of variation in body size among mammals. In Advances in the study of mammalian behavior. Eisenberg, J. F. and Kleiman, D. G. Am. SOC. Mammalogists, Spec. Publ. 7: 632- 663. Shippensberg, PA, USA. Ellison, G. T. H., Taylor, P. J., Nix, H. A., Bronner, G. N. & McMahon, J. P. (1993). Climatic adaptation of body size among pouched mice (Saccostomus campestris: Cricetidae) in the southern African subregion. Global Ecol. Biogeogr. Lett. 3: Graves, G. R. (1991). Bergmann’srule near the equator-latitudinal clines in body size of an Andean passerine bird. Proc. Acad. Hayes, J. P., Speakman, J. R. & Racey, P. A. (1992). The contributions of local heating and reducing exposed surface-area to Hayward, J. S. (1965). Microclimate temperature and its adaptive significance in six geographic races of Peromyscus. Can. J. Lynch, C. D. & Watson, J. (1992). The distribution and ecology of Ofomys sloggetfi (Mammalia: Rodentia) with notes on its Nevo, E. (1989). Natural selection of body size differentiation in spiny mice, Acomys. Z. Saugetierkd. 54: 81-99. Rensch, B. (1932). her die Abhangigkeit der GroBe des relativen Gewichtes und der Oberflachenstruktur der Landschneck- Richter, T. A., Webb, P. I. & Skinner, J. D. (In prep.). Limits to the distribution of the southern African ice rat (Otomys sloggetti): Scholander, F., Hock, R., Walters, V., Johnson, F. & Irving, L. (1950). Heat regulation in some arctic and tropical mammals and Skinner, J. D. & Smithers, R. H. N. (1990). The mammals of the southern African subregion. (2nd edn). Pretoria: University of Sumner, F. B. (1909). Some effects of external conditions in the white mouse. J. Exp. Zool. 7: 97-155. Weiner, J. & Heldmaier, G. (1987). Metabolism and thermoregulation in two races of Djungarian hamsters: Phodopus sungorus sungorus and P. s. campbelli. Comp. Biochem. Physiol. A Comp. Physiol. 86: 639-642. Wunder, B. A. (1978). Implications of a conceptual model for the allocation of energy resourcesby small mammals. Populations of small mammals under natural conditions. Snyder, D. (Ed.). Pymatuning Laboratory of Ecology, University of Pittsburgh, USA, Spec. Publ. 5: 1-237. 41-47. Sci. USA 88: 2322-2325. energetic benefits of huddling by short-tailed field voles (Microtus agrestis). Physiol. Zool. 65: 742-762. ZOO^. 43: 341-350. taxonomy. Navors. Nas. Mus. (Bloemfontein) 8, Part 3. enschalen von den Umweltfaktoren. 2. Morphol. Okol. Tiere 25: 757-807. thermal physiology or competitive exclusion? birds. Biol. Bull. (Woods Hole) 99: 237-258. Pretoria. J. Zool., Lond. (1997) 242, 387-389 Disappearance and later colonization of red deer on Cairn Gorm, Scotland ADAM WATSON c/o Institute of Terrestrial Ecology, Banchory, AB31 4BY, Scotland Introduction The aim here is to present 54 years’ data on remarkable changes in the numbers of red deer (Cervus eluphus) on Cairn Gorm, about 100 km west of Aberdeen, an area of high conservation and recreation importance. The data show the vanishing of a herd that lived there until 1953, and reject the idea that human disturbance caused this.

Disappearance and later colonization of red deer on Cairn Gorm, Scotland

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COMMUNICATIONS FROM THE MAMMAL SOCIETY-NO. 74 387

Debbie Perkins and Chris Chimimba (Transvaal Museum) arranged for access to the mammal collection. John R. Speakman provided valuable criticism of an earlier draft. Thanks are also due to John D. Skinner and Nigel Bennett. Financial support was provided by the Foundation for Research Development (South Africa) and the Bob Blundell Memorial Scholarship.

REFERENCES

Clutton-Brock, T. H. &Harvey, P. H. (1983). The functional significance of variation in body size among mammals. In Advances in the study of mammalian behavior. Eisenberg, J. F. and Kleiman, D. G. Am. SOC. Mammalogists, Spec. Publ. 7 : 632- 663. Shippensberg, PA, USA.

Ellison, G . T. H., Taylor, P. J., Nix, H. A., Bronner, G. N. & McMahon, J. P. (1993). Climatic adaptation of body size among pouched mice (Saccostomus campestris: Cricetidae) in the southern African subregion. Global Ecol. Biogeogr. Lett. 3:

Graves, G. R. (1991). Bergmann’s rule near the equator-latitudinal clines in body size of an Andean passerine bird. Proc. Acad.

Hayes, J. P., Speakman, J. R. & Racey, P. A. (1992). The contributions of local heating and reducing exposed surface-area to

Hayward, J. S . (1 965). Microclimate temperature and its adaptive significance in six geographic races of Peromyscus. Can. J.

Lynch, C. D. & Watson, J. (1992). The distribution and ecology of Ofomys sloggetfi (Mammalia: Rodentia) with notes on its

Nevo, E. (1989). Natural selection of body size differentiation in spiny mice, Acomys. Z. Saugetierkd. 54: 81-99. Rensch, B. (1932). h e r die Abhangigkeit der GroBe des relativen Gewichtes und der Oberflachenstruktur der Landschneck-

Richter, T. A., Webb, P. I. & Skinner, J. D. (In prep.). Limits to the distribution of the southern African ice rat (Otomys sloggetti):

Scholander, F., Hock, R., Walters, V., Johnson, F. & Irving, L. (1950). Heat regulation in some arctic and tropical mammals and

Skinner, J. D. & Smithers, R. H. N. (1990). The mammals of the southern African subregion. (2nd edn). Pretoria: University of

Sumner, F. B. (1909). Some effects of external conditions in the white mouse. J. Exp. Zool. 7: 97-155. Weiner, J. & Heldmaier, G. (1987). Metabolism and thermoregulation in two races of Djungarian hamsters: Phodopus sungorus

sungorus and P. s. campbelli. Comp. Biochem. Physiol. A Comp. Physiol. 86: 639-642. Wunder, B. A. (1978). Implications of a conceptual model for the allocation of energy resources by small mammals. Populations

of small mammals under natural conditions. Snyder, D. (Ed.). Pymatuning Laboratory of Ecology, University of Pittsburgh, USA, Spec. Publ. 5: 1-237.

41-47.

Sci. USA 88: 2322-2325.

energetic benefits of huddling by short-tailed field voles (Microtus agrestis). Physiol. Zool. 65: 742-762.

ZOO^. 43: 341-350.

taxonomy. Navors. Nas. Mus. (Bloemfontein) 8, Part 3.

enschalen von den Umweltfaktoren. 2. Morphol. Okol. Tiere 25: 757-807.

thermal physiology or competitive exclusion?

birds. Biol. Bull. (Woods Hole) 99: 237-258.

Pretoria.

J. Zool., Lond. (1997) 242, 387-389

Disappearance and later colonization of red deer on Cairn Gorm, Scotland

ADAM WATSON c/o Institute of Terrestrial Ecology, Banchory, AB31 4BY, Scotland

Introduction

The aim here is to present 54 years’ data on remarkable changes in the numbers of red deer (Cervus eluphus) on Cairn Gorm, about 100 km west of Aberdeen, an area of high conservation and recreation importance. The data show the vanishing of a herd that lived there until 1953, and reject the idea that human disturbance caused this.

388 COMMUNICATIONS FROM THE MAMMAL SOCIETY-NO. 74

Study area, land use and methods

The area included 11 km2 of alpine land at 950-1300 m on the plateau from Cairn Gorm summit south for 5 km to Ben Macdui, and 23 km2 on Cairn Gorm’s unwooded north slope in Glen More catchment (alpine land at 750-1300m, subalpine moor to 650m, and a lower moor down to native Scots pinewood (Pinus sylvestris) and conifer plantations at 500 m). Some observations were made down to 320m in the valley floor.

Glen More was formerly a deer-forest, with 30-40 stags shot annually before 1939 and an unrecorded hind bag (Whitehead, 1960). After buying it in 1923, the Forestry Commission began planting and fenced red deer out of some sheltered winter grounds, but big unfenced areas remained till the late 1930s. Artificial feeding ended in 1940.

A 1946 aerial photograph shows a deer fence on the plantation’s upper edge, except for a 280-m gap at a defile, which was closed in 1947-48. In 1953, the Reindeer Company fenced red deer out of 160 ha that contained the last tract of unfenced pinewood.

Red deer can be accurately counted on unwooded Scottish hills (Clutton-Brock & Albon, 1989). Each count on the plateau covered all of it, and on the north slope 87-100%.

Results

Each summer (May-October) in 1943-53, I saw red deer (mostly hinds) on the plateau, and none in winter, as was usual on exposed Scottish alpine land. However, summer numbers were falling (Table I). In 1943-54, the mean number seen per summer day per year declined with year (n = 12, r,=0.94, P<0.002), as did the proportion of summer days per year with deer seen jr,=0.95, P<0.002). My last records were of 12 stags and hinds on the plateau’s centre in September-October 1953. Each May-October in 1954-96, I saw none (range = 2-24 visits per year, total = 393 visits).

Each summer in 1943-53, I saw both sexes on the north slope’s alpine land and moor, with up to 40 at a time annually up to 1948, and smaller groups in later years. Similar numbers were on the moor in winter. My last sighting was of 15 stags and hinds on alpine land on 29 November 1953.

From the mid 1970s, rangers began to see a few in the Glen More woods, and tracks in snow showed that they had come from the Rothiemurchus woods to the west, when drifts covered the fences. In 1978-80, I saw small groups at night on roadside grass in Glen More, and in summer 1981,30 stags at dawn near Glen More camp site.

In each year in 1954-89, I saw none on 320 visits to alpine land on the north slope, and none on many annual visits to the moor (except for a few young stags near the main car park at the ski area on six summer days (Watson, 1979)).

Plantation fences broke in 1985-86, and red deer crossed to the moor in 1987. In May 1990,50 stags lay in the reindeer enclosure and 20 hinds grazed reseeded grass by the ski road at dusk and dawn. In each year since, red deer have been seen near the ski road. Culling has been done in each winter since 1988-89 (mean = 38, range = 8-80, both sexes). In September 1995, I saw 20 hinds and calves at the plateau edge, the first evidence there since 1953.

Discussion

In most glens in the Cairngorms massif, no trees have regenerated for decades because red deer

COMMUNICATIONS FROM THE MAMMAL SOCIETY-NO. 74

TABLE 1

Mean number of red deer seen per summer day per year on Cairn Gorm plateau

389

Year Mean Counts* Maximum’

1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955-96

62 88 30 40.5 22 3.3 6.2 4.3 3.1 2.1 2.5 0 0

62 88 30 81

150 40 21 15 17 18 10 0 0

*Counts: 1st value, no. of days when species seen; 2nd value,

Maximum: largest no. seen in a day. Smallest no. seen in a no. of days when observer on area

day was 0 in all years

ate the seedlings. After deer vanished on Cairn Gorm’s plateau and unwooded north slope, thousands of scrubby trees colonized the moor. Pears (1968) inferred a late-1950s peak of colonists, before the public ski road was built in 1960. Miller (1986) inferred a 1969-71 peak, and suggested that walkers attracted by the road’s easy access had disturbed deer, leading to less tree browsing. However, the data on red deer reject this. Deer had gone by 1954 (Table I), and have colonized land near the ski road in recent years despite many walkers. Red deer become less wild on land with many people, and are not known to desert land totally, due to disturbance (Staines & Scott, 1992).

I attribute the red deer’s disappearance to exclusion from sheltered low-altitude winter range by fences for planting and reindeer. Subsequent colonization of woodland, followed by fence breakage, led in recent years to deer colonizing the moor and using the woods in winter.

Subalpine scrub abounds in many northern countries, but not in Scotland because of burning and browsing. Cairn Gorm is of high interest for showing potential for it, which was one reason for designating the Northern Corries a Site of Special Scientific Interest in 1984.

I thank two anonymous referees, B. W. Staines, and D. B. A. Thompson for useful comments.

REFERENCES

Clutton-Brock, T. H. & Albon, S. D. (1989). Red deer in the Highlands. Oxford Blackwell Scientific Publications. Miller, G. R. (1986). Development of subalpine scrub at Northern Corries, Caimgorms SSSI. Banchory: Institute of Terrestrial

Pears, N. V. (1968). Post-glacial tree-lines in the Cairngorm Mountains, Scotland. Trans. bot. Soc. Edinb. 40: 361-394. Staines, B. W. & Scott, D. (1992). Recreation and red deer: a preliminary review of the issues. Banchory: Institute of Terrestrial

Watson, A. (1979). Bird and mammal numbers in relation to human impact at ski lifts on Scottish hills. J. appl. Ecol. 16: 753-764. Whitehead, G. K. (1960). The deer stalking grounds of Great Britain and Ireland. London: Hollis & Carter.

Ecology.

Ecology.