Reindeer Herd Dynamics and Range Ecology on St. Matthew Island, 1957, Study notes of Topography

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Project W-3-R- Caribou. Management Studies

SAINT. MA.rm:Ew · ISLAND REINDEER - RANGE

·· .· ...:worit >Pl.an B ·· ··· · Job No. · ··· ·· ·. APril 30, 1958

Volume (^12) Number 2a

JOB COMPLETION REPORTS

Project W-3-R-12 Alaska April 30, 1958

Wildlife ~nvestigations

Work Plan B Job No. 8

Caribou Management Studies

SAINT MATTHEW ISLAND REINDEER-RANGE STUDIES

David R. Klein, Wildlife Management Biologist James L. Whisenhant, Biological Aid

Robert F. Scott Clarence J. Rhode Supervisor, Game Restoration Executive Officer Alaska Game Commission

Not for Publication

(Reports are preliminary in nature and conclusions are subject to change with further investigation.)

5. To collect information of other animal populations present and any additional information of biological significance as time and logistic& permit,

TECFlNIQUES USED

Field work was done during the period July 15 - August 9, 1957 by David R. Klein and Field assistant James Whisenhant. Transportation of personnel and equipment, both to and from St. Matthew Island, was accom plished by the Coast Guard cutter 1 'Waohusett". A brief stop at Hall Is

land was made on August 9, after departure from St. Matthew Island.

Reindeer Population Counts: The total count of the entire reindeer herd was obtained at a time when the main body of the herd was loea ted on the narrow part of the island south of Big Lake (See Fig. 1). Four con secutive days were spent in making this count and complete coverage of the island was obtained from southeast to northwest. Composition counts were made whenever the opportunity for close observations of reindeer ex isted. Binoculars and a 20-30 power spotting scope were used to aid in the differentiation of sex and age groups. The age and sex of reindeer dying from natural causes was determined from skeletons found throughout the island.

Physical Condition of the Reindeer: During the course of the study twelve reindeer were shot from representative sex and age groups within the population. These animals were examined to determine their physical characteristics and well being. Body and antler measurements and weights were obtained and examinations were made for parasites and other pathologic conditions.

Vegetative Composition and Condition of the Range: A survey of the vegetative complex of the island was made through the use of point-inter cept transects, meter-square study quadnats and extensive plant collections. On the line transects and quadrats.P vegetation was recorded by ground cover, frequency of species occurence, vigor, utilization by reindeer and total aspect2 A representative collection of plants was made from the entire reindeer range. One hundred and fif,ty-eight specimens were collec ted, representing one-hundred and twenty species. Appearance of the vege tation and general aspect of the range was recorded photographically. Most of the plants collected were identified by Dr. Herbert C. Hanson, with cooperation from Fr. M. Duman on the sedges and rushes~ W.C. Steere on the mosses and J .R. Swallen on one species of f2!· Dr. Hanson also supplied invaluable assistance in the interpretation of plant relationships in the ecology of the reindeer range. Mrs. Hildur Krog identified the lichens. Lists of plants collected appear in the Appendix.

Twelve point-intercept transects, one hundred feet long and with recording points at one foot intervals, were established in varying stands of vegetation throughout the island. These transects were laid out with a steel tape and marked at both ends with rock cairnso A photographic

record was obtained for each transect in color and black and white. Lo- ~

cations of the transects were recorded in the field notes and on aerial photos. The information recorded from the transects is summarized in the

"'···

Appendix. An accompanying map shows the locations of the transects (Fig. 27).

Three groups of one-meter-square vegetative study plots were estab lished on sections of the reindeer winter range. Each group consists of four meter-square plots laid out in close association as shown in Figure 2S. Two of the plots in each group were protected from reindeer grazing and trampling by five feet of cattle fencing, topped with two strands of barbed wire (Fig. 15). The two remaining plots were unprotected and avail able to use by reindeer. The ground cover in each of the plots was record ed by species, area covered and height and charted on graph paper at the scale of 1:5. The plots were photographed in color and black and white and a soil well was dug near each group from which samples and a descrip tion of the soil profile was obtained. The vegetative analyses of the quadrats and the soil characteristics are listed in the Appendix. The locations of the quadrats are marked on the map in Figure 27.

Other Biological Data~ During the study there was opportunity to collect information relative to other animal populations on, or adjacent to the island. Lists of mammals, birds and fishes seen, or known to occur, on St. Matthew Island are included in the Appendix with estimates of n~ bers present. A brief summary of suggestions to aid in future temporar.y or permanent habitation of the island is included in the Appendix.

FINDINGS

Island Topography and Weather: St. Matthew Island(N 600 30' by

W 172° 30') is located in the Bering Sea Wildlife Refuge ap?roximately 200 miles south of St. Lawrence Island and 170 miles west of Nunivak Island. It is about 32 miles long by 3~ wide and comprises 12S square miles. The topography of the island is characterized by a series of north-south ridges, with intervening low valleys. The ridges are about a thousand feet high, are in most cases eroded to smooth contours and are of volcanic origin. The precipitous basalt cliffs, formed by the cutting action of the sea on the mountains, indicate that the basic relief of the island was formed by an extensive complex of lava flows. The irregular character of the island is broken in two places on the southern portion where extensive dr.y flats, only a few feet above sea level, extend across the island (Figs. 13 & 14). Earth disturbances adjacent to the cliffs, mentioned by Hanna (1920),are apparently the result of land slippage where concentrations of a mineral, similar to bentonite, occur in the soil and decomposing volcanic rock. This mineral has a marked affinity for water with which it forms a greasy gumbo-like texture, ver.y conducive to mass slippage of the earth.

There are several fresh and brackish water lakes on the island, many of which have been formed by gravel bars built by wave action. Storm tides bring salt water into some of the lakes. Residual snow banks, ground water and precipitation feed the numerous small streams which drain the valleys and empty into the lakes.

The climate of St. Matthew Island is characterized by extreme wind velocities, a moderate temperature for such a high latitude, considerable summer fog and an annual precipitation of 15 inches. A weather summar.y kept by the U.S. Army from September 1943 through August 1944 on St. Matthew Island, is presented in the Appendix.

The Reindeer Herd: The existing reindeer herd on St. Matthew Island is the result of the release of 24 female and 5 male reindeer on August 20, 1944, by the U.S. Coast Guard (Beals, 1944). The animals, which were all two-year-olds, were obtained from the Nunivak Island herd near Nash Harbor and were transported by the Coast Gua.rd Cutter 11 Clover^11 • The ob jective of the release was to establish a small herd as an emergency food

supply during World War II. A Coast Guard loran station and an Army weather

station were maintained on the island during the war years, but both were abandoned before the herd was of harvestable size. Shooting of the newly established animals by the military personnel was not permitted. The is land has been uninhabited since then and no harvest of reindeer has taken place.

Reindeer Population Counts: During July 15-August 9, 1957 a total of 1226 reindeer were counted, with no known duplication existing. While making the counts at the north end of the island some animals were missed due to impaired visibility by fog. Large bulls, which were scattered throughout this area at the time, probably constituted the greater portion of the animals missed. This is also indicated by the disproportionate sex ratio among the older animals in the raw counts. By comparison of the composition counts with the assumed herd composition, it seems likely that

approximately ten percent of the herd was not counted (See Tables l & 2).

Adding the ten percent missed to the total animals counted, gives a round ed population figure of 1350. This represents an average yearly rate of increase of 34 percent since their release in 1944. Actually, it is prob

able that the rate of increase was higher than this during the first few

years, due to the large proportion of producing females in the initial stock and the absence of non-producing young stock. Among reindeer, year ling cows breed and have fawns when they are two years old, while caribou are a year later in this respect. Also, female reindeer on good range frequently are bred in their first year and have their first fawns when they are one year old (Chase, l957)o As sex and age ratios adjusted to more natural conditions, the rate of increase quite likely stabilized at a lower figure. The assumed population growth of the herd in the thirteen years since the original stocking is depicted graphically by the growth curves in Figure 2. Rausch's minimum estimate of 400-500 reindeer in 1954 and Rhode 1 s estimate of 700-800 in 1955, add credence to the assump tion of the herds rate of growth. Scandinavian figures quoted by Hadwen and Palmer (1922) show average herd increase for managed reindeer herds to be about 25 percent. The growth of the reindeer industry in Alaska in the twenty years period from 1902 to 1921 shows an annual net increase of 27 percent, or an annual gross increase of 33.3 percent, if total harvested animals are considered (Hadwen and Palmer, 1922). The reindeer herd on St. Paul Island, also in the Bering Sea, showed an average annual rate of increase of 19 percent during its build-up periodi however, when examined on a yearly basis, this rate fluctuated widely from negative values in two years to as much as 42 percent four years before the peak was reached (Scheffer, 1951).

c

Herd Composition Counts: Herd composition counts of several segments of the herd were obtained. Segregation of fawns from adults was possible for 910 animals. Yearling segregation, which was more difficult and re

quired closer observation, was obtained for 218 reindeer. Three hundred

large bulls were tallied out of the total count of 1226. During the per

iod of the study the cows and young stock, which composed the main body of the herd, remained in the area northwest of the Cape Upright flats and

southeast of peak 940 (Fig. 1), while the large bulls were scattered over

the northwest and southeast extremities of the island. A summarization of the composition counts is shown in Table l and the assumed herd compo sition is shown in Table 2.

The fawn ratio of 26 percent of the total adults, while indicative

of a continuing population increase, is nevertheless, below the indicated level of previous years. This may mean that the herd has already exceeded the point of inflection on the sigmoid growth curve (Fig. 2), and has entered the decelerating phase of population growth. The 34 percent fawn

ratio in the smaller sample counted (218), is probably biased. This count

is the sum of many segregation counts of small bands which are predominant ly cows accompanied by fawns and some yearlings. Barren cows and the major ity of the yearlings usually remained in the larger groups (100 plus).

Natural Mortalitt: ~he skeletons or other remains of 31 reindeer

were found during the course of the study. Whenever possible, these were sexed by examination of the antlers and pelvis and aged by teeth

appearance. No rem&ins of reindeer were found northwest of peak 940,

which reflects the concentration of winter activity on the southeast por• tion of the island. This sample of natural mortality is presented in

Table 3. It is apparent, upon examination of this data, that the greater

portion of animals represented fall in the older age groups and reindeer over eight years of age make up the largest group. This is partiallY ex plaihed by the l~ss apparent nature of the remains of ver,y young animals and the ease with Which they are scattered by foxes. Bearing this in mind, a stratification of this type is logical under a ver,y low mortality rate, which is expected in view of the rate of increase. At first appear ance this sample appears exceptionallt small in view of the total popula tion present. However, the herd is only 13 years old and eight years ago there were less than 200 animals. The low ratio of females to males represented in the sample is quite likely due to the less apparent nature of female remains. The large bleached antlers of bulls were frequently all that could be seen of a skeleton above the surrounding vegetation, while the smaller antlers of cows were not as readily seen and are more subject to de8truction by foxes, mice and shattering by frost action. The large number of antlered bulls represented in the sample indicates that these animals die in the early winter, probably shortly after the rut and prior to the shedding of antlers.

The legs and feet of newborn fawns were found at two different arctic fox dens, however, there was no evidence to indicate the cause of death. Foxes were ver,y effective in locating carcasses of reindeer which had been killed for examination and evidence of their presence at old kills was very common.

60



l'il^ \

(J) 5o \

l'il

~^
0
~ 40
H .. ' ' E-t ~ 30 fz 0 ~ l'il p,.. 20

\

IRausch 1954

fz N 900 H C1l Boo 12: 700 0 H E-t ~

....:I

p,.. 400 0 p,..

200

FIGURE 2. ~sumed population growth of the st. Matthew Island reindeer herd,

1944 - 1957. The broken line curve shOWJF. the instantaneous: percentege rate of population growth of the reindeer since their introduction in 1944. The CI!'WITUltrl.ive population growth is shown by the solid line c:urve for thilli same period.

Six reindeer are known to have died after their antlers had become

entangled in' copper wire at the abandoned Coast Guard station (Fig. 3).

One reindeer was observed to be lame due to a piece of wire wound around

its leg at the knee joint. A shed antler, with about ten pounds of wire

entangled on it, was found four miles from the Coast Guard station.

Physical Condition and Characteristics of the Reindeer: Twelve rein

deer were collected as an index to the health and physical characteristics

of the herd. All animals collected were in excellent physical condition.

Fat deposition was particular~ noticable in the large bulls but active~

growing yearlings and lactating cows were also in good flesh with mesen

teric, subcutaneous and intermuscular fat present. Subcutaneous fat was

pink in all of the specimens, indicating that fat anabolism was taking

place. The two large bulls collected had fat layers on their rumps three

to four inches thick. Hadwen and Palmer (1922) list Octo'ber as the period

when reindeer have attained their maximum fat reserves. Weights and meas

urements, taken from the animals collected, are shown in Table 4. The

weights of all of the reindeer collected are greater than the average

weight range listed for reindeer from other Alaska herds.

Also conspicuous among these animals was the very large and uniform

antler growth on all sex and age groups. "Trophy size" antlers were com...

mon among the large bulls. The measurements from the three large bulls

compare favorab~ with caribou antler measurements and these were by no

means the largest animals present. Figures 5 through 10 show the range

of antler development on some of the reindeer specimens collected.

No warbles, nose bots or other external parasites were found in the

specimens collected. Although the 12 animals collected is admitted~ a

small sample, this indicated absence of warbles and nose bots corresponds

with conditions on St. Lawrence Island where the reindeer herd was free

of these parasites for several years after its establishment (Hadwen and

Palmer, 1922). The original stock was moved to St. Matthew Island in

August when it is most likely .all -the bot ..!ly and :warble grubs had left

the reindeer and .egg laying had not started. Mr. Fred Chase, .liunivak Is

land reindeer manager, has suggested that climatic conditione, rather than

isolation, may be the important factor on St. Matthew Island 1n keeping

the animals free of insect parasites.

All reindeer specimens examined were free of parasites of the lungs

and liver and complete examination of the digestive tract of four reindeer

failed to reveal parasites. Again, the extremes in weatoer conditions on

St. Matthew Island may be detrimental to the completion of the exoteric

stage of the life cycles of some internal parasites. Of course, there are

many parasites which are not eliminated by climatic extremes and these are

quite like~ present in the herd but might not be found in healthy animals.

The significance of the lack of internal parasites in these reindeer is

apparent~ not due to their isolation but more likely is a reflection of

the excellent welfare of the herd at this time. ·

The general well being of these reindeer, which is reflected in their

large body size and antler development, abundant fat reserves and indicated

absence of parasites, are obviously reflections of aspects of their envir

onment. In this respect, the quality of the summer forage is perhaps moat

() (^ ')^ (

Table 4 PHYSICAL^ CHARACTERISTICS^ OF^ ST.^ HAT'IHEW

ISLAND REINDEER, 1957

Date Total Length of Longest

Collected A~e Sex Wei~ht Hind Foot Chest Girth Total Lens:th Beam of Antlers

8/3 fawn^ F^97 15.75 36.50 50.75 10.

8/7 fawn F^107 16.00 38.50 53.25 12.

8/8 1 F 186 17.00 43.50 59.50 23.

8/8 1 F 211 18.25 45.00 61.00 21.

8/1 1 M^235 18.00^ 46.75 62.50 30.

..... 8/4^1 M^219 18.75^ 46.00^ 61.75^ 26.

....

8/3 3 F-r~^245 18.50^ 48.50 70.75 18.

7/17 4 F^ --- 19.00 44.75 68.

8/7 4 F* 247 17.25 45.50 69.00 26.

7/17 7 F* (^) --- 18.25^ 47.00^ 66.

7/20 8+^ M (^) --- 21.25 55.00 82.00 (^) 41.

8/4 8+^ M 404 19.25 62.50 77.25 49.

• lactating

instrumental, as the physiological requirements for growth and development are the highest during the summer season. Complex of Vegetation Present: Vegetation is of the arctic tundra type and is of a more xeric nature than that of the Pribilof Islands. Precipitation at St. Paul Island in the Pribilof group is greater than on St. Matthew Island and averages 24 inches annually. All plants are low growing and only the annual growth of a few forbs and grasses exceeds one foot in height. Willows, the only shrubs present, are decumbent forms. The major plant communities can be broken down into several groups, which are described here briefly. 1.) DRY FLATS: Extensive flats, with well-developed and well drained rocky soils, are located northwest of Cape Upright and southwest of Big Lake. These flats support a dry tundra vege tation consisting mainly of lichens~ willows and sedges. Soil wells disclosed no permafrost and its absence over the greater portion of the island is further indicated by the good soil drainage. Frost boils of 10-30 inches in diameter do occur. The dry flats have supported a greater intensity of winter util ization by reindeer than any other vegetative type. Consequent ly, lichens have been drastically reduced. The analyses of the vegetation at Station 1 and 2 and Transects 2 and 11, which appear in the Appendix, are typical of the dry flats (See Figs.

15, 16, 17~ & 18). Plants occuring on the dry flats are listed

below in their order of abundance: Lichens: Cladonia alpestris, Sphaerophorus globsus, Cetraria cucullata and Thamnolia vermicularis are the most common forms 9 while other forms of Cladonia, Lobaria llnita, Dactyllna arctica" !tt.raria islandiea 9 Cetraria islandica and Nephroma expallidum are also present. Salix crassijulis x ovalifolia grows on raised hummocks a foot to several feet in diameter. Forms of S. arbutifolia replace ~· erassijulis x ovalifolia with increased moisture or where temporary flooding occurs. Carex nesophila is very common throughout the flats. Mosses were apparently instrumental in building the hummocks upon which the willows grow and are mostly Po1ytrichum alpinum. Other plants present, but scattered are~ Artemisia arctica var. beringensis A.trifureata Luzula arcuata Lo nivalis Trisetum spicatum Po!Ysonum viviparum Cardamine umbellata III.P!trwn nigrura

Pedicularis capitata Lagotis glauca Lfcopodium selago ~ bipartita Saxifraga hieracifolia

;!. punctata

Luzula wohlenbergii

4.) WET, POORLY-DRAINED MEADOWS: Bog meadows are common in some

sections of the flats, in broad valleys and low mountain passes where level ground is poorly drained. Sedges predominate in such sites. Eriophorum augustifolium and !· russeolum var. albidum are very common but do not form true hummocks characteristic of the sub-arctic muskegs. Carex stans and ~· bipartita occur as codominants on these sites and are grazed heavily by reindeer in the summer. The intervening areas between the sedges are occupied by Sphagnum sp., other mosses, a few lichens (Cladonia alpestris, Thamnolia vermicularis and others)and such higher plant forms as Petasites frigidus, Rubus arcticus, Potentilla palustris and Salix arbutifolia. The vegetative summaries from Transects 4 and 5 are typical of the bog meadow type (Fig. 21). Evidence of the presence in the past of permafrost on the island is indicated in some of the low bog meadows where 11 pingo 11 mounds have been pushed up by frost action (Fig. 22).

5.) ROCK RUBBLE FIELDS AND HIGH RIDGE TOPS~ Vegetation on high, rock rubble fields and ridge tops of frost-sorted scree is mainly restricted to crustose lichens. Frost action is very apparent in these locations, forming stone polygons and stripes, and on the ridge tops, sorting the scree into a "pavement" of rocks of uni form size (Fig 14.) Soil formation is very limited, occuring in pockets where fine material has been brought to the surface by frost boils. Where protection from the wind is afforded, these soil pockets support lush growths of lichens 9 including Cladonia alpestris~ Sphaerophorus globosus and others. ~ nesophila is interspersed with the lichens. Unfortunately, the total area occupied by the "pockets" of vegetation is small.

6.) STABILIZED BEACH RIDGES: Immediately behind the gravel beaches are located bands of almost pure stands of Elymus mollie on the old, raised beaches. Stabilization of the sand and gravel of these old beaches is taking place, however, "washouts" from recent st91rms are evident. Scattered through the stands of E!Ymus are Angelica lucida, Lathyrus maritimus, Cochlearia officinalis, Senecio pseudO-arnica and Calamagrostis deschampsioides.

Several other vegetative types, or plant communities, are present on St. Matthew Island but they are of less importance as reindeer range and occupy restricted areas.

Immediately inland from the ~grmus beach ridges, between Big Lake and ~ the sea, is a flat expanse about 0 yards wide by four miles lo~g which is ~ grown almost exclusively to Empetrum nigrum (Fig. 23). It is a dry,

well-drained flat, with a ver,y thin soil layer overlying coarse irregular shaped gravel. Widely scattered in this matrix of Empetrum, which is quite depauperate, are plants of Salix arbutifolia, O~ropis nigrescens, Artemisia arctica var. beringensis and Deschampsia caespitosa. A few other examples of this community are found under similar conditions throughout the island but they are quite limited in size.

Adjacent to several of the large lakes are flood plains which are inundated annually or every few years. Water levels in the lakes can be raised through storm tides, which flood over the beach dykes, excessive spring runoff and raising of the beach dykes through wave action. These flood plains, with rich alluvial soils, support lush growth of grasses and some !orbs and willows. Deschampsia caespitosa is the dominant grass often forming pure stands. Forms of Salix arbutifolia occur commonly on these sites as well as Rumex fenestratus. The vegetation recorded in Transect 8 in the Appendix, is typical of these lake flood plains.

Other vegetative types occupying limited areas include: lake shores with rushes, Potentilla palustris and Ranunculus hzyerboreus predominant; lakes and ponds where Hippuris vulgaris, Equisetum palustre and Potamogeton sp. are present; and cliff faces where Cochlearia officinalis, Arenaria peploides, ClarYonia acuti!oli3 and a few grasses grow luxuriantly in the crevices in the rock, fertilized by droppings from the sea birds.

The Reindeer Range - Summer Use: Evaluations of range condition and

the effect of ungulate utilization are difficult tasks on any range. On

the tundra biome, where perennial growth does not exceed a few inches, variations in range conditions are not obvious. Lacking accurate know ledge of the appearance of the range in previous years, a certain amount of speculation is involved in estimating changes that have taken place. Until several years accumulation of systematic vegetative measurements are available, rather general observations of indicator plants and apparent vegetative changes resulting from reindeer activity, must be relied upon.

Sumser forage, for reindeer on St. Matthew Island, shows no apparent

deterioration through over-utilization by the present reindeer herd. DUr

ing the field studies, reindeer were observed to use the well-drained sedge meadows and bog meadows almost exclusively for summer grazing (Types 3 & 4). In these types, sedges are dominant, or very common, and are eaten extensively by the reindeer. On the drier, better-drained meadows, ~ nesophila is the most abundant sedge and receives the brunt of sum mer use, while the wetter, boggy sites support a wider variety of sedges but 2.• stans is usually the dominant form and receives the heaviest use. Other sedges, leaves stripped from willows, grasses and !orbs are also -important components of the summer diet of reindeer. Frequently, the flowering or fruiting parts, were all that were eaten from same plants, such as Rumex fenestratus and Arnica lessingii. All vegetative types receive some summer use by reindeer, however, only the types with a high proportion of sedges are utilized consistently.

The quality of the low-growing plants of the arctic tundra, which make up the summer forage, are apparent~ highly nutritious, as reflected in the excellent physical condition of the reindeer. The hi~h nutritional value of some types of arctic vegetation, which is associated with the long

Up to the present, the greatest concentration of winter use by rein deer,has been on the two areas of large dry flats and adjacent low ridges

on the southeast end of the island (Figs. 13 & 15). Late winter aerial

observations, made by Regional Director Clarence Rhode, in 1955, revealed large numbers of reindeer using these areas. As one travels northwestward, up the length of the island, evidence of winter utilization, such as winter droppings, shed antlers and lichen deterioration, becomes less common and finally disappears completely at the extreme end. The northwest end of the island, north of peak 940 in Figure 1~ has no extensive flats and is interrupted by many small valleys and intervening ridges. There are also extensive areas of "rock pavement" where soil development has not taken place. These veritable deserts on much of the northwest end of the island apparently result from the absence of surface water, due to the excellent drainage afforded by the decomposing bedrock. The entire northwest end apparently receives only limited summer use by a small number of large bulls.

Vegetation on the heavily utilized wintering areas adjacent to Big Lake and Cape Upright readily shows the effect of reindeer use. Lichen growth has been seriously depleted through the combination of winter graz ing, trampling and shattering and actual removal of the dry, shattered pieces of lichen by the persistently strong winds. With wind velocities often averaging in excess of 20 knots during winter months, the potential for plant desiccation and erosion is great (See Weather Summary). Lichen growth, which formerly occupied the slight depressions between the raised hummocks of prostrate willows, has been almost completely removed. Lichen growth on these over-grazed areas apparently was quite similar in the past to ungrazed areas at the northwest end of the island and on reindeer-free

Hall Island where the lichen mat is 3-4 inches deep (Figs., 18 & 25).,

Now the lichen mat on the winter range seldom exceeds an inch in depth and is composed of badly shattered lichens unattached to the ground., Unfortunately, the preferred lichen species, such as Cladonia alpestris, are the most vulnerable to shattering through trampling, while the more resilient forms which resist shatteringJ> such as Thamnolia vermicularis, are less palatable to reindeer and make up a smaller percentage of the original stands.

The willows on the winter range have fared somewhat better than the lichens and in fact~ have increased their area of ground coverage as com petition with the lichens has decreased. In similar lichen-willow-sedge stands at the northwest end of the island, which have not been utilized by reindeer, the willows and sedges have been suppressed by the engulfing growth of lichens., While the removal of lichens on the winter range has stimulated growth of willows and sedges 9 more recently reindeer have been forced to rely heavily on the willows with the result that evidence of this heavy use is also apparent on these prostrate shrubs. Exposed stems and some "die back" occur on willows throughout the dry flats and low ridge tops at the south end of the island as a result of reindeer browsing, paw ing and trampling., Widely scattered willows growing in the Empetrum nigrum flat•~ between Big Lake and the sea, have suffered the greatest damage from pawing.

Sedges on the winter range have apparently increased as a result of the reindeer activity on the lichens much the same as .the Jrdllows ..ha.Ye. However, while the willows have increased their ground coverage whol~ through expanded growth of existing plants, the sedges appear to have extended their coverage through both rhizome sprouting and.reseeding. Also, the sedges which are mostly Carex nesophila, have not been important constituents of the reindeer's winter diet while lichens were abundant, although they are utilized extensive~ during the summer. Evidence from other reindeer ranges indicate that when lichens are depleted, grasses and sedges are grazed extensively during the winter (Palmer, 1929).

On the dry flats where utilization by reindeer has been most intense and the lichen flora has been virtually eliminated, some wind erosion of

the fine organic surface duff has taken place. The mineral soil is not

as susceptible to wind erosion due to its high moisture content from frost thawing in summer and its frozen nature in winter. The surface character of the flats, with the raised hummocks of willow and intervening depressions occupied by the lichens and sedges, also tends to preclude wind erosion. Frost boils are common throughout the flats and can be mistaken for erosion due to reindeer activity, particularly so when the imprints of several hooves remain in the firm mud of the boils. The windswept, vegetated ridge tops, which are segments of winter range, are more readily eroded by wind action when the vegetative cover is disrupted. On these sites both the plant cover and the layer of organic duff are much thinner than on the lower flats and the effect of feeding and trampling by reindeer is more ~ pronounced. Evidence of moderate to severe wind erosion of both the organic ~ surface layer and the finer mineral soil were encountered on the more exposed ridges where wind velocities are greatest. Figure 20 shows the effects of wind erosion in exposing the roots of DEfaS and in the establish ment of a pebble l'fer as the finer mineral soil has been blown away.

Invasion of deteriorated lichen-willow-sedge range by other less de sirable species has not occured to a significant extent. On a few of the more xeric low ridges and slopes, the impression is gained that Drzas and Empetrum have increased their area of surface coverage as the destruction of the lichen growth exposes more mineral soil. However, the growth of dense mats of Drzas and Empetrum are restricted in area and occur only on the dry and exposed ridge tops and old gravel flats adjacent to the beach.

Extensive reindeer trails, such as are characteristic of long-used caribou range, are not found on the island. Single trails have developed through narrow passes, in V-shaped canyons, and where lake shores crowd adjacent hillsides. Apparently, the movements of reindeer on the island are dispersed and not usual~ !£masse so that the parallel trails of migration found on caribou ranges have not developed here.

Conclusions: It is obvious, from the herd counts and the projected population growth curve (Fig. 2), that the reindeer on St. Matthew Island have rapidly increased in 13 years to occupy an apparently very favorable virgin range. At their present rate of increase, saturation of the range is imminent. Fawn counts indicate that over-population is beginning to J have its effect on productivity. Present density on the island is 10. reindeer per square mile, however, the north half of the island is not