PRELIMINARY OBSERVATIONS OF THE TARUCA (HIPPOCAMELUS ...

PRELIMINARY OBSERVATIONS OF THE TARUCA (HIPPOCAMELUS ANTISENSIS, CERVIDAE) IN SOUTHERN PERU NICHOLAS

A.

ROE AND WILLIAM

E.

REES

ABSTRACT.-Ecological and behavioral observations of a little-known highAndean deer, the taruea (Hippocamelus antisensis), are reported from the Lake Titicaca basin, southern Peru. The deer's conservation status is considered vulnerable, with declining numbers. Tameas were seen in groups numbering from three to 14 individuals, consisting most often of one adult male, one yearling male, and several adult and yearling females. We describe features of its pelage, size, and other physical characteristics, as well as its semi-arid, mountain grassland habitat. Also described for the first time are dominance, threat, courtship and mounting, flight, group, and comfort behavior. Several of the behavior patterns described are similar to patterns reported in North American cervids. AU observations were recorded between 8 and 13 June 1975.

The taruca or North Andean huemul (Hippocamelus antisensis d'Orbigny, 1834) is a species of deer presently categorized as "vulnerable," that is, it is likely to move into the endangered category in the near future if the factors causing the depletion of its numbers continue operating (International Union for the Conservation of Nature and Natural Resources [I.U.GN.J, 1972). Formerly distributed in the Andean highlands from northwestern Argentina through western Bolivia and northeastern Chile, Peru and Ecuador, the taruca is now considered depleted throughout its range, and it may be extinct in Ecuador (Cabrera, 1961). Unfortunately, with the exception of the Venezuelan white-tailed deer (Odocoileus virginianus gymnotis) (Brokx, 1972), data on the ecology and behavior of neotropical cervids (six genera, eleven species) that might contribute to their conservation and management are sparse and fragmentary. Thus the need for knowledge of taruca is important to both conservation and science (Geist and Walther, 1974; Cowan and Holloway, 1973). From 6 to 15 June 1975, we visited the Hacienda Checayani (latitude 14° 49' South, longitude 70°01' West), Provincia de Azangaro, Departamento de Puna, Peru, with the aim of locating a long-term study area for the species, We describe here the salient features of these preliminary observations. We adopt the common name taruca in preference to North Andean huemul (Cowan and Holloway, 1973) since this Quechua Indian name for the species has been widely adopted by Spanish-speaking Peruvians. It also serves to distinguish the huemul (H, bisulcus), presently differentiated from the taruca, and found in central and southern Chile and neighboring areas of Argentina. METHODS

Observations were made on foot with the aid of both 7 X and 8 X binoculars and a 20x to 45X spotting scope, equipped with a zoom lens. In general, one observer would watch the animals and dictate notes to the other observer, who also acted as timekeeper.

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PHYSICAL CHARACTERISTICS

Size The females observed were noticeably smaller than the males. Those individuals classified as yearlings were smaller than adult females, and were perceptibly shorter in the muzzle than adults. Pearson (1951) measured the shoulder heights of two adult males at 77 and 74 centimeters (em), and two adult females at 69 and 71 em. Other published shoulder heights vary from 78 to 80 em (Walker, 1964) to 91 em (Whitehead, 1972). In the field the taruca gives the impression of being stockily built.

Pelage The general coloration is sandy gray, but there appear to be slight sexual, individual and age differences. Adult females and yearlings in general appear browner than adult males, but there is some variation among individual fe~ males. The general coloration provides excellent camouflage against the characteristic background of dry vegetation and broken sandstone rocks. Having located one yearling male standing grazing in open grassland interspersed with rocks, our untutored eyes took 48 minutes (min.) with the aid of binoculars and spotting scope before perceiving all six individuals comprising the group of which it was a member. This occurred at a distance of 250 meters (m) with the animals in the open and no group member positioned further than 40 m from any other. Only when standing or lying such that the white parts of the pelage are visible in contrast with the background are tarucas easily visible. Most individuals shared a pronounced, dark Y-shaped facial pattern on the head extending posteriorly from approximately 2 em above the rhinarium to the pedicle area. This pattern was blacker in two adult males than in adult females, but was almost entirely lacking in a third adult male. Females exhibited two black spots in the approximate position of the pedicles, and in one case these formed the apices of a dark, horizontally-compressed diamond pattern on the forehead. AU individuals exhibited a white crescent around the black rhinarium. In one adult male, this crescent was offset by a black outline both in the commencement of the facial Y-shape, and in black cheek patches. The cheek patches in a yearling male were less obvious but generally more pronounced than in adult females. Thc large ears are tipped with black and show a dark streak down the inside axis. The throat and neck are conspicuously whitish, perhaps more markedly in adult males than in others. The forelegs are also conspicuously white anteriorly, and are in part offset by a dark line extending along the lower part of the flank that outlines the body. The hind legs appear darker than the forelegs. The tail has a dark patch at the base, with a less dark stripe extending posteriorly for about half its length. The underside of the tail is white. When the animals are calm, the rump patch appears a light fawn color, conspicuously lighter

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than the back. In flight, it appears whiter when erect and puffed out (see Behavior ). One adult female exhibited four black spots on her right side, three on the flank and ODe on the upper hind leg.

Antlers The antlers, found only in males and consisting of two branches in a simple fork, have been measured at 27, 22, and 25 em in length (Pearson, 1951). One yearling male had the posterior branches only in the form of spikes. We estimate that the length of the spike was just over half that of the ear, or approximately 10 em. One adult male had the right posterior branch missing. All adult males had antlers that appeared free of velvet.

Cumds We observed what appeared to be tarsal glands located in the position common to Odocoileus. We have found no other reference to the tarsal gland on taruca in the literature, although it is visible and possibly covered in urine in a photograph in Walker (1964: 1397). The glands were visible on both sexes, and in the case of a courting adult male, marks streaming from them down the metatarsus may indicate that courting males urinate on them in the manner described by Geist (1966) for Odocoileus hemionus and other cervids, although we did not observe this behavior. HABITAT AND FEEDING

Hacienda Checayani lies approximately 50 kilometers (km) northwest of Lake Titicaca within the lake's drainage basin at an altitude of 3900 m above sea level. The area is characterized by broad, flat, frequently marshy valley bottoms separating steep-sided, round-topped mountains. The climate is semi-arid, with a wet season at its peak in January and February, and a dry season in June and July. During our study period (6 to 15 June), heavy frosts occurred nightly, while in the daytime temperatures rose to 18° Celsius (65° Fahrenheit) and above. The weather was said to be unusually wet (there were several brief afternoon showers) and relatively warm during our stay. The tarucas were all observed at altitudes between 3950 and 4200 m. They were observed only on the crests and slopes of mountains in areas where bare rocks and small cliff-like outcroppings interspersed dry grassland vegetation. The habitat is very similar to that described by Jungius (1974) for taruca in northwestern Bolivia. Grimwood (1969) has stated that the presence of cover in the form of thickets of quenoa (Polylepis sp.) trees determines the distribution of the taruca, Questioned on this point, our host lng. Humfredo de Macedo informed us that an area further to the south of our study area has these

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thickets, and that tarucas certainly use them. However, this was clearly not the case in our study area, as we found only scattered specimens of quenoa growing in sheltered arroyos, and certainly too few to be of importance to the taruca. As it was the dry season at the time of our visit, we anticipated finding evidence of movement down to the valleys in search of water. Indeed local Indians told us that they frequently observe tarucas watering in the valley bottom streams at dawn, and that the animals return to these streams from the hills in the late afternoon. However, we were unable to find direct evidence of this implied diurnal movement. On the other hand, on some mountain tops we found pools remaining in otherwise dry streams, and water behind man-made impoundments, both of which showed evidence of use by tarucas. These water sources, when available, might obviate the need for descent into the valleys. Domestic cattle, sheep, and llamas are found in abundance in the study area, particularly, but by no means exclusively, in the valley bottoms during June. Although we were unable to determine the precise content of their diet in June, all the tarucas observed grazing appeared to avoid the larger bunched grasses that grow in profusion, and fed with a nibbling action on smaller plants growing either very close to the ground or in cracks between rocks. The follOWing grasses and sedges were common constituents of the slopes where we observed tarucas grazing: Mulhenbergia peruviana; Calamagrostis heterophylla; Calamagrostis spiciformis; Festuca humilior; Scirpus rigidus. Woody shrubs included Diplostephium sp. and Margyricarpus strictus. Unfortunately we were unable to find flowering specimens of many other species of grasses, shrubs, and "rock-plants," which precluded their positive identification. A detailed study of the feeding habits of taruca and the floral composition of their habitat over a full cycle of seasons is a component of our proposed long term study. GROUP COMPOSITION AND BEHAVIOR

vVe categorized individuals into adult or yearling age classes on the basis of body size and antler development. Pearson (1951) calculated that a male with short spike antlers and lacking "last" molars was about eight months old. We have classified individuals with short spike antlers as yearling males, and individuals of equivalent body size but with no antlers as yearling females. Adult males show a large, pendulous scrotum as well as branched antlers. The muzzle length of those classed as yearlings was perceptibly shorter than that of those classed as adults. We observed no fawns.

Group Composition All observations of tarucas were made in daylight at distances from 50 to 1000 m, between 08:17 hours (hr) and 14:50 hr in the period 8 to 15 June,

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TABLE I.-Composition of groups of Hippocamelus antisensis during six observation periods in southern Peru. Ohservation period

Adult males

I

2 0

2 3 4 5 6

I I I

2

males

Adult females

Yearling females

I

4

I I I I I

Yearling

2 3 3 I 3 (+ 12 undifferentiated)

0 0 0

1975. During the six observation periods totalling 500 min. of study, groups were composed as shown in Table 1.

Group Behavior Movements of the groups which we observed were consistently led by adult females. Adult males consistently brought up the rear of group movc* ments, whether the movements involved grazing or not. While resting, individuals in the group of six (Observation period number 5) all lay down facing away from each other. During five out of the six contact periods we noticed one of the group more preoccupied with standing and looking around than the rest of the group. In one instance, an adult female stood staring fixedly in our direction for 35 min., although neither she nor the group showed any sign of alarm or awareness of our presence. In another instance, having caused a group to flee over a ridge, we observed a yearling male reappear back over the same ridge moving in our direction. He stopped, regarded us for a few minutes, then lay down where mostly concealed but able to observe us. Investigation behavior and motionless staring for several hours at human intruders have also been described for H. bisulcus (Prichard, 1902; Gigoux, 1929) .

Courtship and Mounting From our observations, rutting activity is apparently common in the study area in June, during the dry season. On 13 June, we observed three instances of courtship and mounting behavior in a group consisting of one adult male, one yearling male, three adult females, and one yearling female, In all in~ stances, the group had been lying down when the interactions were suddenly initiated by the adult male. In two instances, the sequence of events was almost identical. The adult male suddenly arose from a resting position with penis semi-erect and approached a female with head low. He nosed and licked the vulva of a reclining female, then placed his snout in her inguinal region and literally heaved her hindquarters off the ground, as many times as it took to force her to stand, She moved a few paces, arched her back and

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urinated, The male tested the urine (we could not tell if he drank it) and exhibited flehmen, He would follow her and continue to lick and nose her vulva and lift her hind quarters, once eliciting urination a second time, As he approached from behind he flicked his tongue around the labial-nasal area continuously, We observed the adult male mount on three occasions, each time mounting a different female, including the yearling, On two occasions the penis was seen to be fully erect. The mount lasted no longer than two seconds, and on no occasion was intromission achieved. The male commenced grazing shortly after mounting, The courtship and mounting sequences lasted 6, 3, and 2 min., respectively, from initial approach to ultimate grazing. Females flicked their tails with head upright or grazed between the approaches, One adult female, on being momentarily courted, lifted her tail and defecated immediately after the male nosed her vulva, In one instance the whole group was brought to its feet by the adult male's behavior; in another instance, only the adult male and the selected female were standing, The yearling male showed close interest in the adult male's activities, both while standing and lying down, In addition to the courtship behavior described above we observed a fleeing female on 13 June with what appeared to be blood staining the white rump hairs surrounding the genital area, As she fled, she was followed closely by an adult male. These observations accord with the findings of Whitehead (1972) who states that the rut in Peru occurs between June and August, and Pearson (1951) shot two pregnant females on 23 December and estimated birth in February or March from the size of one fetus, We are also reliably informed (Humfredo de Macedo, personal communication) that in our study area fawns are dropped in January and February, Interestingly, Brokx (1972) notes evidence of mating behavior all year round in Venezuelan white-tailed deer, but a peak in rutting activity in the dry season, as does Gardner (1974) for the red brocket deer (Mazama americana) in Peru, Adult Male / Yearling Male Interaction On 8 June, we observed an interaction that had elements of aggressive, ritualized display, and play behavior. It took place on, above and below ca, 2 m-high rock face, It terminated 41 min, after we commenced observations; this was therefore its minimum duration. The most spectacular behavior consisted of the adult male in a standing position throwing his head upwards and backwards with chin pointed skywards while facing the yearling male, In this way the conspicuous whiteness of the throat and neck was vividly exposed, The adult male sometimes followed this by head-nodding and raising the forelegs one at a time from a normal posture. He also pointed his antlers at the yearling male, with head held perpendicular to the ground and neck in line with the back. The adult

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male (A) frequently followed or approached the yearling male (B) with a "stiff" walk, but never violently or at a run, nor did the animals "spar" with each other. An excerpt from our field notes describes a typical 5-min, section of this interaction: B in front of A. A throws head back. B jumps downslope. A followschin high-white neck visible. B flicks tail, runs away. A moves along parallel to B. A throws head back and slightly toward B-B flicks tail. B turns and runs back in opposite direction-A on ledge turns and followsthrows head back. B jumps back 3 steps, turns and runs in opposite direction-A again follows, head high. B turns and runs three steps downslope, then runs along and upslope to top of ridge. A approaches head high-B turns, runs half dowoslope (A has noticeably white forelegs). A [standing] raises both forelegs in turn up and down several times. B remains downslope, head oriented away from A, tail flicking. B moves forward sniffs A's antlers lwhich are in «point" posture]. A moves and B bounds downslope. Notably, the adult male did not flick his tail during the interaction. The yearling male, as well as tail~flicking, occasionally grazed. A yearling and two adult females watched the interaction for several minutes, and fled rapidly when briefly approached by the adult male at one stage. At no time did either male move further than 30 m from the rock face. Each repeatedly ascended and descended it, the adult male usually following the yearling. The seemingly "coquettish" behavior of the yearling and constant interest of the adult gave an impression of play. The neck~exposing display appears similar to behavior described in other cervids as the biting threat, which is associated with a display of the canine teeth, or possibly the head~high threat, which may signify an intention to rise on the hind legs and strike with the fore feet (Geist, 1963; DeVos et al., 1967). Brooke (1878) credits both sexes of Hippocamelus 'p. with upper canines, although the frequency of their occurrence and their size are subject to dispute (Walker, 1964; Cabrera and Yepes, 1940). Guthrie (1971) has remarked that the dark spot on the lower lip of most cervids may serve to offset the whiteness of canine teeth in display. We could not tell whether the taruca exhibits this spot, but there is much dark hair in the labial-nasal area (see Physical Characteristics).

Reactions to Disturbance Tarucas seem predisposed to look downslope when alerted or when lifting their heads from grazing. We were able to approach in view to as close as 50 m before the animals fled. While fleeing, the animals generally cantered, with hairs on the rump appearing to be erect and possibly everted, making them look whiter than when relaxed, and having the effect of broadening the rump patch area. This makes tarucas reminiscent of both pronghorns (Anti-

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locapra americana), a comparison which Pearson (1951) has also made, and other cervids. After flight, they generally hid just over the tops of ridges, from where their heads and ears could be seen as they watched us. They are very agile on rocks, and were seen to jump onto and over a 1.5 m-high stone wall with ease. Comfort Movements

While lying down, a common posture involved stretching both forelegs forward and resting the chin and head on them in very dog-like fashion. An adult male and a yearling male appeared to doze while lying down with heads thrown backwards and laterally across their sides, thus exposing their white necks and throats. A yearling male also appeared to doze on his side with head upright and all four legs stretched out parallel to the ground. All other resting postures observed were similar to those reported for other cervids. The longest period of rest (most members of the group lying down, dozing, and ruminating) observed in a group was 4 hrs and 6 min. between 09.19 hr and 13.25 hr. The animals seemed unaware of our presence 250 m away during and after their rest period. We hope that our further research will provide detailed information on similarities between the taruca and other cervids, and contribute to its conservation and management. ACKNOWLEDGMENTS

We are deeply indebted to lng. Humfredo de Macedo for his hospitality during our stay at Checayani. Also we thank Dr. Hernando de Macedo, Jefe Titular, Seccion Ornitologia y Mastozoologia, Museo de Historia Natural "Javier Prado," Universidad Nacional Mayor de San Marcos, Lima, for his invaluable assistance and encouragement, and for identifying plant species. Dr. Antonio Brack and lng. Sanguinetti of the offices of Dr. Marc Dourojeanni R., Director General, Forestal y de Fauna, and Ing. Carlos F. Ponce del Prado, Director, Direccion de Conservacion, all of the Ministedo de Agricultura, Government of Peru, Lima, gave advice and encouragement, as did 5rs. Felipe Benavides and Jose J. Rada of World Wildlife Fund Peru. The research was partly funded by grant #A9890 from the National Research Council of Canada. Additional support came from the Faculty of Graduate Studies and School of Community and Regional Planning at the University of British Columbia. LITERATURE CITEn

BROKX, P. A. J. 1972. A study of the biology of Venezuelan white-tailed deer (Odoeoileus virgininnus gymnotis Wiegmann, 1833) with a hypothesis on the origin of South American cervids. Unpublished Ph.D. dissertation, Univ. Waterloo, Ontario, Canada, 355 + 85 pp. BROOKE, V. 1878. On the classification of the Cervidae, with a synopsis of existing species. Proc. Zool. Soc. London, pp. 883-928. CABRERA, A. 1961. Catalogo de los mamiferos de America del Sur. Rev. Mus. Argentino Cienc. Nat. "Bernardino Rivadavia," ZooL 4(2) :308-732. CABRERA, A., A:-'O J. YEPES. 1940. Mamiferos sud-americanos (Vida, Costumbres y Descripci6n). Historia Natural Ediar. Campania Argentina de Editores, Buenos Aires, 370 pp.

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COWAN, I. MeT., AND C. W. HOLLOWAY. 1973. Threatened deer of the world: conservation status. BioI. Conserv., 5:243-250. DEVOS, A., P. A. BROKX, AND V. GEIST. 1967. A review of social behavior of the North American cervids during the reproductive period. Arner. Midland Nat., 77; 390-417. GARDNER, A. L. 1971. Postpartum estrus in a red brocket deer, Mazama americana, from Peru. J. Mamm., 52: 623-624. GEIST, V. 1963. On the behaviour of the North American moose (Alces alees andersoni Peterson, 1950) in British Columbia. Behaviour, 20:377-416. 1966. Ethological observations on some North American cervids. Zoologische Beitrage (new series), 12:219-250. - - - , AND F. WALTHER (eds.). 1974. General Introduction. Pp. 11-13 in The he. haviour of ungulates and its relation to management, Vol. I, I.U.C.N. Pub!., New Series No. 24, Morges, Switzerland, 940 pp. GIGOUX, E. E. 1929. EI huemu!. Revista Chilena de Historia Natural, 33:573-582. GRIMWOOD, I. R. 1969. Notes on the distribution and status of some Peruvian mammals. 1968. Spec. Pub!., American Committee for International Wildlife Protection and New York Zoological Society, Bronx, New York 21:1-86. GUTHRIE, R. D. 1971. The evolutionary significance of the cervid labial spot. J. Mamm., 52,209-212. INTERNATIONAL UNION FOR THE CONSERVATION OF NATlJll.E AND NATURAL RESOURCES. 1972. Red Data Book. Vol. L Mammalia. Sheet No. 19.125.10.2. Morges, Switzerland. JUNCIUS, H. 1974. Beobachtungen am Weisswedelhirsch und an anderen Cerviden in Bolivien. Z. Saugetierk., 39:373-383. PEARSON, O. P. 1951. Mammals in the highlands of southern Peru. Bull. Mus. Camp. Zool., 106:115-174. PRICHARD, H. 1902. Field·notes upon some of the larger mammals of Patagonia, made between September, 1900 and June, 1901. Proc. Zool. Soc. Land., pp. 272-277. WALKER, E. P., et al. 1964. Mammals of the World. Johns Hopkins Press, Baltimore. l:xlviii 1-644. WHITEHEAD, G. K. 1972. Deer of the World. Constable and Co., London, 194 pp.

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Institute of Animal Resource Ecology and School of Community and Regional Planning, University of British Columbia, Vancouver, British Columbia, Canada, V6T lW5. Sub· mitted 30 July 1975. Accepted 11 April 1976.