Hoof and foot loads for reindeer (Rangifer tarandus)

Mauri Nieminen

Finnish Game and Fisheries Research Institute, Reindeer Research, Koskikatu 33A, SF-961 00 Rovaniemi, Finland

Abstract: Hoof and foot measurements and body weights were taken from 60 living semi-domesticated reindeer (Rangifer tarandus tarandus L.) (8 female and 13 male calves, 10 young females (age 2 yrs), 9 young males (age 2-3 yrs) and 20 adult hinds) at the Kaamanen Reindeer Research Station during the winter 1988. The outline of the hooves and the feet (hoof + dew claws) from front and hind legs were drawn when pressed down on a hard substrate in a natural position. Measurements were taken also from foot prints of 26 wild forest reindeer (R. t. fennicus Ldnn.) (7 calves, 11 hinds and 8 stags) made on hard snow surfaces in Kuhmo and Salamajarvi national park during 1985-88. Reindeer had bigger hooves and feet on front than on hind legs, and male calves had bigger hooves and feet than female calves. Hoof and foot areas of wild forest reindeer (means 74.6 and 200.3 cm2 for calves, 79.4 and 230.4 cm2 for hinds and 83.6 and 258.6 cm2 for stags) were bigger than those of semi-domesticated reindeer (means, front legs, 60.9 and 165.3 cm2 for calves and 78.9 and 214.1 cm2 for hinds, respectively). There were significant correlations between live weight and hoof areas (r=0.839 and 0.792), between live weight and foot areas in front and hind legs (r = 0.714 and 0.664) and between live weight and foot area when supported by 4 legs (r = 0.726) in semi-domesticated reindeer. Load on ground and foot load in semi-domesticated reindeer when supp• orted by 4 legs were 235 and 85 g/cm2 in calves and 268 and 102 g/cm2 in hinds.

Key words: snow

Rangifer, Special Issue No. 3, 1990: 249-254

Introduction toes can be bent sharply to assume an almost Reindeer and caribou (Rangifer tarandus) spend horizontal position. In fact, the reindeer hoof over 40 per cent of each year in snow. They are can be considered in a state of transition toward true chinophiles (Formozov 1946, Pruitt 1959), a plantigrade foot (see Nasimovich 1955). which means that they are highly adapted to Those adaptations greatly increase the surface snow. They have blunt toes, crescent-shaped area of the hoof and help the reindeer to float hooves with a sharp edge for grip on hard snow on soft snow. and ice and functional lateral digits, or dew External morphology and behavior reflect claws. A heavy growth of bristle-like hairs sur• adaptation to snow. The measurements of the rounds the hoof, and the joints of the middle foot area is a prerequisite in the determination

Rangifer, Special Issue No. 3, 1990. 249 of load on ground and, hence, an important measure of the adaptability of mammals to snow of various depths, densities and hard• nesses. The load on ground can be divided up into hoof load and foot load (Thing 1977). The hoof load is the measurement most frequently used in the literature (Nasimovich 1955, Kel- sall 1969), but the foot load seems to be a more realistic measurement since the whole hoof- pastern-dew claw area offers support in snow (Telfer Ac Kelsall 1979). The ability to move in snow not only depends on the snow characteristics, but also on the load on ground and length of legs of the animals. No comparative studies are available on the lo• ad on ground between the various reindeer po• pulations. This paper describes hoof and foot measurements for semi-domesticated and wild Fig. 1. Diagram of a reindeer foot seen from be• forest reindeer and calculated hoof and foot lo• low showing hoof and foot lengths and hoof ads for semi-domesticated reindeer in Finland. outline. Hoof area = Al + A2 + Bl + B2 cm2 and foot area is obtained by adding to Material and methods Al + A2 area the area of the rectangle Hoof and foot measurements and body weights (foot length — distance Ax hoof width (see were taken from 60 freely grazing and supple• Kelsall & Telfer 1971). mentary fed semi-domesticated reindeer (8 fe• on hard snow surfaces in Kuhmo and Salamaj- male and 13 male calves, 10 young females (age arvi national park during 1985-1988. 2 yrs), 9 young males (age 2-3 yrs) and 20 adult Hoof and foot loads were calculated for each hinds) at the Kaamanen Reindeer Research Sta• reindeer by dividing live weights by the combi• tion during winter 1988. Hoof and foot charac• ned area for all 4 hooves or feet. The load on ters of living reindeer were measured to the ne• ground was calculated also for moments when arest millimetre with a steel metric rule. Broken the reindeer was supported by 4, 3, 2 or 1 foot hooves were omitted. The outline of the hoofs (Fig- 2). and the feet (hoof + dew claws) from the left Results and discussion front and hind legs were drawn when pressed Results are given in Tables 1 and 2. Reindeer down on a hard substrate and in a natural posi• had bigger hooves and feet on front than on tion. Hoof and foot areas were calculated ac• hind legs, and male calves and young males had cording to Kelsall & Telfer (1971) (Fig. 1). To bigger hooves and feet than female calves and be sure that the hoof and foot areas were as young females. According to McCullough correct as possible, control measurements were (1965) no significant differences existed be• taken on distinct reindeer foot prints on hard tween sexes in measurements of hooves in snow surfaces to determine space between the black-tailed deer fawns (Odocoileus hemionus), hooves and the distance between hind edge of but differences in yearlings and adults were sig• hooves and dew claws (Thing 1977). Measure• nificant. Hoof and foot areas of wild forest

ments were taken also on distinct foot prints of 2 reindeer (means 74.6 and 200.3 cm for calves,

26 indentified wild forest reindeer (Rangifer t. 2 79.4 and 230.4 cm for hinds and 83.6 and fennicus Lonn.) (7 calves, 11 hinds and 8 stags) 2 258.6 cm for stags) in present study were big-

250 Rangifer, Special Issue No. 3, 1990. FRONT FOOT / / SLOW WALK o o • 4» OO. ««* OQ LEFT to •V 0 o

• 0-^7 «^ • RIGHT o \ HIND FOOT

FOOT ON THE GROUND HEAVY DIAGONAL GALLOP / OO o LEFT o OO o a o o c o OQ OO RIGHT oo OO OO OO Fig. 2. Graphic representations of the symmetrical normal walk and heavy diagonal gallops of reindeer and their support graphs, ger than those of semi-domesticated reindeer ly and absolutely, than the wild Norwegian (means, front legs, 60.9 and 165.3 cm2 for cal• mountain reindeer and semi-domesticated ves and 78.9 and 214.1 cm2 for hinds, respecti• reindeer (Nieminen 1980, Nieminen 8>C Helle vely). The length of the dew claws in wild forest 1980). According to Banfield (1961), the hoof reindeer was also bigger than that of semi- size in wild Fennoscandian mountain reindeer domesticated reindeer (Table 1, Fig. 3). males is 60 x 60 mm and in wild forest reindeer There were significant correlations between males 110 x 95 mm, which may indicate consi• live weight and hoof areas (r= 0.839 and derably lower load on ground in the wild forest 0.792, n = 60, P< 0.001) between live weight reindeer. It is concluded, that the long legs and and foot areas of front and hind legs (r= 0.714 low load on ground of the wild forest reindeer and 0.644, n = 60, P <0.001) between live are important adaptations to taiga conditions, weight and foot area when supported by 4 legs where the snow cover is usually very deep and (r= 0.726, n=60, P< 0.001) in semi- soft (see Nieminen 5c Helle 1980). domesticated reindeer (Fig. 4). The hoof load The lowest hoof loads and foot loads were and the foot load in semi-domesticated reinde• calculated in present study for calves and young er, when supported by 4 legs, was 235 and 85 reindeer (Table 1). The hoof load and the foot g/cm2 in calves and 268 and 102 g/cm2 in adult load are important when one wants to know females (Table 1). how hard the snow cover has to be in order to In the present study, hoof and foot measure• support a reindeer. If it is too soft, the reindeer ments of wild forest reindeer were taken from will sink through and therefore have to use distinct foot prints on hard snow surfaces. more energy when walking than if it was Thus it can be supposed that there appear to be walking on top of the snow cover. Usually the some measurement errors in this material. Ho• load on ground is calculated by dividing total wever, it has long been known that both in wild body weight with total hoof or foot area, and it and semi-domestic stocks in Finland and Swe• will then only refer to an animal standing still den the differences are clearest between the on all 4 feet and not to an active and moving mountain and forest reindeer forms (Lonnberg animal. However, information on load on 1909, Klemola 1928, Itkonen 1948). The wild ground has practical value only when given for forest reindeer is 10-15 cm taller than the mo• 1, 2, 3, or 4 feet as according to the different untain reindeer and semi-domesticated reinde• ways of locomotion used by the animal in uestion. As can be seen in Fig. 2, the reindeer er. It has significantly longer legs, both relative- Rangifer, Special Issue No. 3, 1990. 251 Cu C/5 > n o re co p . i-t-» 3 i r r 3 3 C/3Q (rø3 F+ M F+ M c/5 2 Tl Tl 2 Tl 2 Kl Kl Oo o O Hin d Fron t Hin d Fron t Hin d Hin d Fron t Hin d Fron t Hin d Fron t Fron t OT

o o NO NO NO po po po po Oo 00 D X w |-- o 4* 't— k) b Ö NJ1 kl N_n ki 4> ON kl 4>. kl ^° 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ o p p p p p p p p ^8 p p p ppp NI ki I— '•— 'M kl 3 vjj NJl 4^ Ctq 9- Oo ON ON ON ON wi ON 4>. 00 o 4^ 00 P p o Kl >° ON 4* ON 4>. VO I— Ö NO kl ON kl KJ 18 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ l+ Kl Kl wo Kl O 4* O Kl bo bo 4». kl 4* Ö bo 4> bo \-A ON ki

po po 4- ON vjl ON ON _4> 4* NJl 4^ ON kl NO ON >— ON kl kl 'o kl bo kl b 3 n 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ p p p p p p p p p p p p o o O bo 4v b\ kl kl kl k) kl kl 3 %

Kl Kl Kl Kl Kl 4* ON po Kl Kl NO Kl 00 po ON O re re o kl 4* ON b bo kj 4» b 4* ON 'o 1+ 1+ 1+ 1+ 1+ 1+ 1+ i+ 1+ 1+ 1+ 1+ 1 + 1+ 1+ p p o p p p P o P p boo 4* ON Ö Ö 4». bo kj ON ki Wl bo 4- 4* 1 1

!z: Kl Kl P Kl NO P O 'o bo ki ON NO kl b kl 'o ki ki '^nb ^8 1+ 1+ 1+ 1+ 1+ 1 + 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ p o p p P p p p p P p p p OoN 4>. ON ki kl ki kpl ki

Kl 55 po po ^4 ^4 ON ON ON ON ON ON kl 4* ON NO kl ON bo 'o ^ I 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1+ p p p p p P p P re" p P p p o o p 3 ki NJI kl ki kl 4>. kl Kl Kl OT

Kl Kl Kl Kl NJl wo © "-4 ON 00 \JI ON 4» ON ON NJ1 5¬ po O p 4>. ON ON ON 4- VJl 4^ ;-4 ON po ON 4* 4* 00 'UJ NO Ul kl UJ bo Oi NO 4> 3. 1+ 1+ 1+ 1+ 1+ 1+ 1+ 1 + 1+ 1+ 1+ 1+ 1+ 1 + 1+ 8 4* NJ1 ON 4* po NO 4* vjl bo NO 'o kl Ö kl >— b b 4- 4^ kl ON ON o OT < ON NO

1+ 1+ 1+ 1+ 1 + H- K) 1—• OT 3"

Kl Kl Kl Kl Kl Kl ON ON ON OT X ^1 00 4^ 4^ Wl "~ 2 bo 'o UJ bo '•— kl 3 ^ 1+ 1+ 1+ 1+ 1+ !+ 0 v-n 4>- po Kl Cu 4* 0 *~* kl kl

0 NO 00 00 0O 0 00 4>. _4^ 4v 1 bo kl kl 4^ kl € 3 NO Q 0 1+ 1+ 1+ 1+ 1+ 1+ 3 Z. 4* Kl ^ o u bo 0 kj 'o kl kl Cu 252 Rangifer, Special Issue No. 3, 1990. Table 2. Foot load values (g/cm2,x ±_ S.E.)of semi-domesticated reindeer supported by 1, 2, 3 or 4 feet.

Calves Young females Young males Adult females Front foot (N = 21) (N=10) (N=9) (N = 20)

<* *•» 84.7 i 1.9 9^.2 ± 4.7 98.8 i 3.9 101.9 ± 1.8 Right • <*» •«r Hind foot

0 • «r • <•* • <•* 111.0 i 2.4 124.7 i 6.5 129.6 i 5.2 132.6 i 2.3

od •A OC • «r 161.1 ± 3.5 184.9 ±. 11.6 188.3 ± 7.8 191.0 ± 3.6 oa oc?

OC? • «K of* • «r

• 169.4 i 3.8 188.6 ±. 8.8 197.6 ± 7.8 203.9 ± 3.7 od oC* oo

OÄ OC 322.5 i 7.0 370.8 i 23.1 376.6 ^15.8 378.9 ± 6.7 oQ OC^ oC? oo

• cpt og OC7 358.3 i 10.0 386.6 ± 14.8 417.5 i 17.5 442.9 ± 9.9 oca oo

• Ä oc=» • •r 0C7 • <*k OQ 179.2 ± 5.0 193.3 i 7.4 208.8 ± 8.8 221.5 i 4.9

Foot on the ground will be supported by only 2 or 3 feet at any time when it is walking. When the reindeer is mov• ing in a heavy diagonal gallop it is supported by 1 or 2 feet only at any movement (Fig 2). Reindeer hoof load is only about 125 to 180 g/cm2 when standing (Nasimovich 1955, Thing 1977), 500 g/cm2 when walking, and 1 000 g/cm2 when trotting (see Thing 1977), compared with 390 to 659 g/cm2 for standing moose (Telfer 8c Kelsall 1979). In the present study the foot load of semi-domesticated rein• deer was only about 85 to 102 g/cm2 when standing and maximally 358 to 443 g/cm2 when the reindeer was moving in a heavy diago• LIVE WEIGHT, KG nal gallop and supported by 1 foot (see Table Fig. 4. Regression between live weight and total 2). The effects of speed on the foot loads were foot area supported by 4 legs in semi- not taken into consideration. domesticated reindeer (r = 0.726, n = 60.

Rangifer, Special Issue No. 3, 1990. 253 Fig. 3. Wild forest reindeer (R. t. fennkus, Lönnb.) have bigger hooves and feet and is also 10 - 15 cm taller than wild mountain and semi-domesticated reindeer. Photo L. Rautiainen.

Conclusions Kesall, J.P. & Telfer, E.S. 1971: Studies of the physical Semi-domesticated reindeer, and especially adaption of big game for snow. - In: Proc. of the snow and ice in relation to wildlife and recreation Symp., Iowa wild forest reindeer are well adapted to travel State Univ., Ames., pp. 134-146. through deep and soft snow. Hoof and foot areas Klemola, V. 1929: Poronhoidosta ja sen levinneisyydesta and length of dew claws are bigger in wild fo• Euraasiassa. - Terra 11:137-163. rest reindeer than in semi-domesticated reinde• Lonnberg, E. 1909: Taxonomic notes about Palearctic er. Reindeer hind legs have bigger hooves and reindeer. - Arkiv Zool. 6(4):1-18. feet, and males have usually bigger hooves and McCuIIough, D.R. 1965: Sex characteristics of black- tailed deer hooves. - J. Wildl. Manage. 29(1):211-212. feet than females. There are significant correla• Nasimovich, A.A. 1985: The role of the regime of snow tions between live weight and hoof and foot are• cover in the life of ungulates in the U.S.S.R.M.os\ixa, as in reindeer. The results indicate that infor• pp.402. mation on load on ground has a practical value Nieminen, M. 1980: The evolution and taxonomy of only when given for 1, 2, 3 or 4 feet as accord• the genus Rangifer in northern Europe. - In: Proc. 2nd Int. Reindeer/Caribou Symp. Røros, Norway, pp. ing to the different ways of locomotion. 379-391. Nieminen, M. 8C Helle. T.1980: Variation in body References measurements of wild and semi-domestic reindeer (Rangifer tarandus) in Fennoscandia. - Ann. Zool. Fennici Formosov, A.N. 1946: Snow cover as an intergral fac• 17:275-283. tor of the environment and its importance in the ecolo• Pruitt, W.O., Jr.1959: Snow as a factor in the winter gy of mammals and birds. - Fauna and Flora of the ecology of barren-ground caribou. Arctic - 12(3):158-180. USSR. New Series. Zoology 5 (xx). Occ. Publ. No. 1. Telfer, E.S. 8t Kelsall J.P.1979: Studies of morpho• Boreal Inst., Univ. Alberta, Edmonton, pp. 141. logical parameters affecting ungulate locomotion in Itkonen, T.1948: Suomen lappalaiset vuoteen 1945. II. snow. - Can. J. Zool. 57(11): 2153-2159. Porvoo - Helsinki, pp 629. Thing, H. 1977: Behavior, mechanics and energetics Kelsall, J.P. 1969: Structural adaption of moose and associated with winter cratering by caribou in northern deer for snow. - J. Mammal. 50:302-310. Alaska. - Biol. Paper of the Univ. of Alaska No. 78:1-43.

254 Rangifer, Special Issue No. 3, 1990.