FileList Convert a pdf file! Koedoe 19: 63-66 (1976) A NOTE ON MOUNTAIN REEDBUCK REDUNCA FULVORUFULA FULVORUFULA AFZELIUS IN THE KRUGER NATIONAL PARK L. R. IRBY Caesar Kleberg Research Programme in Wildlife Ecology Department oj Wildlife and Fisheries Sciences Texas A & M University College Station Texas 7784) Abstract - This survey was conducted to obtain information on the mountain reedbuck population in the Kruger National Park for comparison with the population in the Loskop Dam Nature Reserve, Transvaal. During 93 hours of search effort, 36 mountain reedbuck sightings were recorded. All of the sightings were in the Malelane Hills on slopes above the Kwa Machiyaliwane drainage. Introduction Mountain reedbuck in the Kruger National Park (KNP) are found only in the Malelane Hills and along the Lebombo Mountain. The population is estimated to number 240 (Pienaar 1969). The status of this species in the Park is considered precarious by many people, but too little is known of its population structure and distribution to determine whether the population is declining or merely occupying a limited area of suitable habitat (Smuts, pers. comm.). During February and September 1970, 19 days were spent in the Park surveying the mountain reedbuck population in the Malelane Hills. The object of the survey was to obtain information for comparison with the mountain reedbuck population in the Loskop Dam Nature Reserve located near Groblersdal, Transvaal. This paper is a condensa- tion of observations made during the survey. Methods Mountain reedbuck were located in four ways: 1. Scanning hillsides with 7 x 35 binoculars and a 60 x spotting scope; 2. Waiting by watering sites at dawn and sunset; 3. Walking ridgelines accompanied by a game scout; 4. Driving firebreak roads. Results Only SIX individual mountain reedbuck were sighted during 52,5 63 hours of observation in February (Table 1). All sightings were in the hills along the Kwa Machiyaliwane drainage even though a comparable amount of time was spent in the vicinity of Khandizwe Hill and along the eMcwebeni drainage. Table 1 Relative intensity of sampling and success using four techniques for sighting moun- tain reedbuck in the Kruger National Park February September Observation Animals Observation Animals Time Sighted Time Sighted Technique (h) (h) Spotting scope and binoculars 18,6 0 2,1 3 Driving firebreaks 15,0 4 3,9 0 Waterhole counts 3,0 0 4,3 0 Foot transects 15,9 3 30,0 27 Efforts in September were more successful (Table 1). Of 30 animals sighted, at least 25 were not resightings. Group size ranged from one to six. Table 2 gives group size, composition, and general habitat informa- tion for the September sightings. All of the animals were located on hills above the Kwa Machiyaliwane drainage in Combretum woodland. Most of the groups were seen on west-facing slopes on a burned area east of the Kwa Machiyaliwane streambed. None were more than 5 km from the Matjulwana windpump. Discussion The low number of sightings recorded in February was probably due to visibility restrictions imposed by the fully-leafed vegetation. Several of the sightings in September would not have been made if the trees were not bare. The presence of juveniles in September (Table 2) indicates that moun- tain reedbuck are reproducing in the Park and that lambs are surviving until the end of the dry season. Although the small sample size precludes any conclusions on the population trends of this antelope in the Park, the lamb to ewe ratio in the KNP is greater than the lamb to ewe ratio of the relatively stable Loskop population for the same period (Table 3). 64 Table 2 Group size, composition, and site characteristics rif mountain reedbuck sighted in the Kruger National Park during September 1970 HABITAT GROUP COMPOSITION CHARACTERISTICS TIME 1515 0840 1012 1655 0705 0810 0830 0855 0710 GROUP SIZE Male Female Imm. (>1 a) (>1 a) «1 a) 1 3 2 6 1 (whistle only) 3 5 4 1 2 2 2 2 1 2 1 Table 3 Un- aged 4 1 1 1 Slope H t. on Recent Face Slope Burn W 3/4 yes SW 3/4 yes S 3/4 yes W 1/4 yes W 3/4 yes ? 1/4 yes SW 2/3 yes NW 4/5 yes E 3/4 no Comparison rif mountain reedbuck sightings in the Loskop Dam Nature Reserve during August-September 1970 with sightings in the Kruger National Park during September 1970* Lamb: ewe N Males Females Lambs Unaged Ratio (> 1 a) ( > 1 a) ( < 1 a) (lambs per 100 females) LOSKOP 50 14 25 6 5 24 KRUGER 26 3 10 5 8 50 * Groups sighted in intensive study areas at Loskop have been excluded. The 24 km 2 section of the Kwa Machiyaliwane drainage surveyed yielded a minimum count of 25 mountain reedbuck. Exclusion of 3 km 2 of flats associated with the main streamcourse gave a minimum density of 1,2 mountain reedbuck per km 2 of slope habitat. A similar treatment of sightings at Loskop during June-August 1973 (Irby 1973), gave a minimum count of 205 individuals on 49 km 2 for a minimum density of 4,2 per km 2 of slope habitat. While the two counts are not directly 65 comparable, since the search intensity was greater at Loskop, the data indicate that the Kwa Machiyaliwane sub-population is less dense than that of Loskop. The absence of sightings around Khandizwe Hill and along the eMcwebeni drainage may indicate a decline in the population, and a subsequent decrease in the range occupied, or only insufficient effort expended to locate individuals in a very sparse population. New growth on burned grass clumps in the Kwa Machiyaliwane area could have con- centrated mountain reedbuck in that region. A mass migration from the eMcwebeni drainage to this burn seems unlikely since comparable burns, with no mountain reedbuck, were observed in the eMcwebeni drainage, and mountain reedbuck are territorial. Acknowledgements I wish to thank Dr. U. de V. Pienaar and the National Parks Board of Trustees for allowing me to work in the Kruger National Park and the staff of the Park for the guidance and assistance provided during my stay. Dr. S. L. Beasom deserves thanks for reviewing this manuscript. Funding for this study was provided by the Mammal Research Institute, University of Pretoria; the Caesar Kleberg Research Program in Wild- life Ecology, Texas A & M University; and the National Science Founda- tion, Washington, D.C. Material presented in this paper will be used for partial fulfillment of the requirements for a Ph.D. degree from Texas A & M University. This manuscript is Texas Agricultural Experiment Station Technical Article No. TA 12059. REFERENCES IRBY, L. R. 1973. Mountain reedbuck in the Transvaal. Unpublished annual report of the Caesar Kleberg Research Program in Wildlife Ecology. 108-115. PIENAAR, U. de V. 1969. Predator-prey relationships amongst the larger mammals of the Kruger National Park. Koedoe 12: lO8-176. 66 Page 1 Page 2 Page 3 Page 4