Activity budgets and activity rhythms in red ruffed lemurs (Varecia rubra) on the Masoala Peninsula, Madagascar: seasonality and reproductive energetics

The activity budgets and daily activity rhythms of Varecia rubra were examined over an annual cycle according to season and reproductive stage. Given the relatively high reproductive costs and patchy food resources of this species, I predicted that V. rubra would 1) travel less and feed more during seasonal resource scarcity in an attempt to maintain energy balance, and 2) show sex differences in activity budgets due to differing reproductive investment. Contrary to the first prediction, V. rubra does not increase feeding time during seasonal food scarcity; rather, females feed for a consistent amount of time in every season, whereas males feed most during the resource-rich, hot dry season. The results are consistent with other predictions: V. rubra travels less in the resource-scarce cold rainy season, and there are some pronounced sex differences, with females feeding more and resting less than males in every season and in every reproductive stage except gestation. However, there are also some provocative similarities between the sexes when activity budgets are examined by reproductive stage. During gestation, female and male activity budgets do not differ and appear geared toward energy accumulation: both sexes feed and rest extensively and travel least during this stage. During lactation, activity budgets are geared toward high energy expenditure: both sexes travel most and in equal measure, and rest least, although it remains the case that females feed more and rest less than males. These similarities between female and male activity budgets appear related to cooperative infant care. The high energetic costs of reproduction in V. rubra females may require that they allot more time to feeding year round, and that their overall activity budget be more directly responsive to seasonal climate change, seasonal food distribution, and reproductive schedules.     

Activity patterns of a troop of Japanese monkeys (Macaca fuscata yakui) on Yakushima Island,Japan

Activity patterns of Japanese monkeys (Macaca fuscata) were observed for 240 hr from August to December 1976 on the western slope of Mt. Kuniwari, Yakushima Island, Japan. Activity patterns and the time budget of a habituated wild troop which consisted of 47 animals in August 1976, were studied quantitatively by using the scan-sampling method at 15-min intervals. Six thousand seven hundred and six animals were recorded in 959 scans during the study period and the mean number of animals seen per scan was 7.0. The time budget established for different categories of activity was as follows: inactive—20.9%; moving—22.8%; feeding—23.5%; social grooming—27.9%; self-grooming—1.2%; and other activities—3.7%. Adult males spent less time in feeding and more time in resting or being inactive than females or juveniles. The daily activity patterns were highly variable with respect to time. Intraspecific variations were examined between troops in several regions of Japan and it was noted that the percentages of time devoted to feeding were similar in all areas. Inter-species variations in the activity budgets of several species of primates were also examined. The percentage of time spent in social grooming by Japanese monkeys is exceptionally high compared to that recorded in other species.     

弄岗熊猴的活动节律和活动时间分配

2005年9月至2006年9月,采用瞬时扫描取样法,在弄岗国家级自然保护区对野生熊猴(Macaca assamensis)进行了连续跟踪观察,收集相关的活动节律和活动时间分配的数据,通过分析其与气候及食物组成的关系,从中探讨影响熊猴活动节律及活动时间分配的因素。研究结果发现:在熊猴的日活动节律中,觅食活动表现为逐渐增强的趋势,最高峰值出现在下午15:00,休息活动在中午出现一个小的高峰;其日活动节律表现出明显的季节性差异,主要表现为旱季大部分时间段的觅食强度均高于雨季,且早上7:00-10:00出现一段长时间的休息,而雨季里长时间的休息则发生在中午12:00-14:00;在活动时间分配上,熊猴平均花费39.6%时间用于休息,33.2%用于移动,18.3%用于摄食,5.1%用于理毛,2.4%用于玩耍,1.4%用于其他行为,其活动时间分配也表现出明显的季节性差异;与雨季相比,在旱季熊猴明显增加用于觅食的时间,而相应地减少用于休息的时间,活动时间分配的季节性变化明显与食物组成的变化有关;在不同年龄组个体间,青少年猴花费更多的时间用于玩耍,而用于休息和理毛的时间明显少于成年猴。     

内蒙古达赉湖地区蒙原羚繁殖期及其前后昼间行为时间分配及能量平衡策略

2007年11月、12月和2008年3月,在内蒙古达赉湖地区,采用扫描取样法对雌雄蒙原羚繁殖期及其前后昼间行为时间分配进行了研究。 研究表明：（1）繁殖期前、繁殖期和繁殖期后,雌性蒙原羚采食时间,占昼间活动时间的比例分别为（44.9±3.8）%、（43.5±4.0）% 和 (46.2±3.1)%;卧息时间,占昼间活动时间的比例分别 为（32.3±4.8）%、（29.2±2.9）% 和 (28.0±4.8)%;雌性蒙原羚在繁殖期及其前后采食、移动和卧息的行为时间分配差异不显著（P>0.05）,站立、繁殖、“其他”行为时间分配差异性显著（P<0.05）。（2）繁殖期前、繁殖期和繁殖期后, 雄性蒙原羚采食时间,占昼间活动时间的比例分别为 (52.6±3.8)%、(17.5±2.8)% 和 (29.8±4.8)%;卧息时间,占昼间活动时间的比例分别为 (13.4±6.4)%、(24.2±4.1)% 和 (44.2±4.7)%。雄性蒙原羚在繁殖期及其前后采食、卧息、站立、移动、繁殖、“其他”时间分配均有显著差异（P<0.05）。动物采食卧息的行为时间分配反映动物的能量平衡策略。雌性蒙原羚的时间分配表明,雌性蒙原羚的能量平衡策略在繁殖期前、繁殖期和繁殖期后没有发生显著变化,均为能量摄入最优化策略,尽可能多的时间分配在采食上;雄性蒙原羚的时间分配表明,在繁殖期前,其能量平衡策略为能量摄入最优化策略,尽可能多的时间分配在采食上;雄性蒙原羚繁殖期及繁殖期后其能量平衡策略转变为能量支出优化策略,尽可能少的支出能量,尽可能多的时间分配在卧息上。     

Activity budgets of woolly spider monkeys,or muriquis (Brachyteles arachnoides)

One group of woolly spider monkeys, or muriquis (Brachyteles arachnoides), was observed from June 1983 through July 1984 at Fazenda Montes Claros, Minas Gerais, Brazil. The study subjects spent an average of 49% of their daylight time resting, 29% traveling, and 19% feeding. They shifted their diurnal schedule of activities in response to seasonal changes in temperature and rainfall. The activity budgets of adult males and females were similar. However, a comparison of three adult females in different reproductive conditions revealed that the lactating female spent a greater proportion of time feeding than did both the pregnant and nonreproductive females. Intraspecific differences in group size and diet appear to be important to understanding differences in the activity budgets of Brachyteles. Differences between locomotion patterns of woolly spider monkeys and sympatric howler monkeys may explain activity budget differences based on group size and diet.     

The effects of lactation and infant care on adult energy budgets in wild siamangs (Symphalangus syndactylus)

In mammals with biparental care of offspring, males and females may bear substantial energetic costs of reproduction. Adult strategies to reduce energetic stress include changes in activity patterns, reduced basal metabolic rates, and storage of energy prior to a reproductive attempt. I quantified patterns of behavior in five groups of wild siamangs (Symphalangus syndactylus) to detect periods of high energetic investment by adults and to examine the relationships between infant care and adult activity patterns. For females, the estimated costs of lactation peaked at around infant age 4–6 months and were low by infant age 1 year, whereas the estimated costs of infant‐carrying peaked between ages 7 and 12 months, and approached zero by age 16 months. There was a transition from primarily female to male care in the second year of life in some groups. Females spent significantly less time feeding during lactation than during the later stages of infant care, suggesting that female siamangs do not use increased food intake to offset the costs of lactation. Female feeding time was highest between infant ages 16 and 21 months, a period of relatively low female investment in the current offspring that coincided with the period of highest male investment in infant care. This suggests that male care may reduce the costs of infant care for females in the later stages of a reproductive attempt. The female energy gain resulting from male care was likely invested in somatic maintenance and future reproduction, rather than the current offspring. Am J Phys Anthropol, 2009. © 2009 Wiley‐Liss, Inc.     

The effect of urban and rural habitats and resource type on activity budgets of commensal rhesus macaques (Macaca mulatta) in Bangladesh

Macaques are characterized by their wide distribution and ability to adapt to a variety of habitats. Activity budgets are affected by habitat type, season, and food availability in relation to differing age–sex class and individual requirements. We conducted a comparative study on two commensal rhesus groups, one living in a rural village and the other in the center of urban Dhaka, Bangladesh. The study was conducted in three different seasons between 2007 and 2009 in order to evaluate how habitat type and season affects their behavioral activities. Differences in food type and its availability between these two habitats were mainly responsible for the variations in activity budgets between groups. Feeding time in the rural group was significantly longer than that in the urban group. In contrast, grooming and object manipulation/play were significantly greater in the urban than the rural group. Seasonal variations in all major behaviors were significantly affected by group, with more time spent feeding in summer than in winter/dry season, and more time spent grooming and moving in winter/dry season than summer in the rural group. In contrast, time spent resting was greater in the monsoon and summer seasons than the winter/dry season in the urban group. Grooming time was greater in the winter/dry season than the monsoon and summer seasons. In both groups, immature of both sexes spent significantly more time on feeding and object manipulation/playing and less time resting than adults. Adult females spent more time grooming than males and immatures, of both sexes, in both groups. Moreover, the rural group spent most of their time feeding on garden/crop produce and wild plant food resources, while the urban group spent more time feeding on provisioned foods. These results showed that differences in the activity budgets of rural and urban dwelling macaques were due largely to the differences in available food resources. Commensal rhesus macaques show a high degree of behavioral flexibility in response to habitat and resource variability, and knowledge of these differences is important for the conservation and management of highly commensal primates.     

Sexual segregation in Tibetan gazelle: a test of the activity budget hypothesis

Tibetan gazelle Procapra picticaudata , a threatened endemic species on the Qinghai-Tibet Plateau, is a sexually dimorphic ungulate. Males are larger than females and both sexes live in different groups, except during the rutting season. In order to test the activity budget hypothesis, which was proposed to explain social segregation in ungulates, we studied the activity budget of male and female Tibetan gazelles during the summers of 2005 and 2006. The activity budget hypothesis predicts that females spend more time feeding and group members synchronize their activities more in the same-sex groups than in the mixed-sex groups. We found that females and males of Tibetan gazelle had different activity budgets; females spent significantly longer time feeding and comparably less time on other activities. Activity synchronization indexes between female groups and male groups were similar (female groups: 0.81±0.17, male groups: 0.80±0.19), whereas both of them were significantly higher than that of mixed-sex groups (0.58±0.29). These results suggest that although sexual segregation might be caused by multiple mechanisms, the activity budget hypothesis about sexual segregation is supported by our studies of Tibetan gazelle on the Qinghai-Tibet Plateau.     

Western lowland gorillas (Gorilla gorilla gorilla) change their activity patterns in response to frugivory

The most important environmental factor explaining interspecies variation in ecology and sociality of the great apes is likely to be variation in resource availability. Relatively little is known about the activity patterns of western lowland gorillas (Gorilla gorilla gorilla), which inhabit a dramatically different environment from the well‐studied mountain gorillas (G. beringei beringei). This study aims to provide a detailed quantification of western lowland gorillas' activity budgets using direct observations on one habituated group in Bai Hokou, Central African Republic. We examined how activity patterns of both sexes are shaped by seasonal frugivory. Activity was recorded with 5‐min instantaneous sampling between December 2004 and December 2005. During the high‐frugivory period the gorillas spent less time feeding and more time traveling than during the low‐frugivory period. The silverback spent less time feeding but more time resting than both females and immatures, which likely results from a combination of social and physiological factors. When compared with mountain gorillas, western lowland gorillas spend more time feeding (67 vs. 55%) and traveling (12 vs. 6.5%), but less time resting (21 vs. 34%) and engaging in social/other activities (0.5 vs. 3.6%). This disparity in activity budgets of western lowland gorillas and mountain gorillas may be explained by the more frugivorous diet and the greater dispersion of food resources experienced by western lowland gorillas. Like other apes, western lowland gorillas change their activity patterns in response to changes in the diet. Am. J. Primatol. 71:91–100, 2009. © 2008 Wiley‐Liss, Inc.     

Time budgets and sex differences in the Eurasian beaver

The Eurasian beaver, Castor fiber, is one of the few obligate monogamous mammal species known, and nothing is known about the time budget of the mated pair. We investigated whether mated adult Eurasian beavers would display sex differences in time budgets. Using radiotracking, we obtained behavioural data on six mated pairs of adult beaver during 2000 and 2001 on two rivers in southeast Norway. Time budgets for males and females were compared in total and over the seasons, along with temperature data collected throughout the study. The three main behaviours of both males and females were travelling, foraging and being in the lodge, accounting for 92.0 and 93.2%, respectively, of each sex's overall time budgets. Time budgets did not differ between the sexes except that males allocated more time to travel. Time budgets for each sex did not vary with season, and water and air temperature data were positively correlated with time spent travelling for both sexes. These results support the hypothesis that male and female time budgets are similar, except for the time that males and females allocated to travel. We suggest that the similarities in behaviour result because parental care by both parents is essential to the successful rearing of offspring, leading to reduced behavioural sexual dimorphism; nevertheless, some differences still occur, perhaps relating to the male's indirect parental care. Copyright 2003 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.      

Time Budget and Activity Patterns of Oncilla Cats (Leopardus tigrinus) in Captivity

Researchers have reported on the diet of Leopardus tigrinus and ecological aspects, but studies of behavior are scarce. The aims of this study were to describe the time budget and activity patterns of 10 captive Leopardus tigrinus individuals. The group had an activity budget of 66% resting, 20.66% moving, 6.08% vigilant, 3.12% feeding, and 4.14% other activities during 720 hr of observations. The activity budgets of the males and females did not differ significantly; however, males ate more than did females. The nonhuman animals spent more time resting during the day than during the night. Moving, socializing, maintenance, and vigilance showed statistically higher mean values at night. Group analysis of the temporal pattern of behavior showed bimodal peaks. Activity levels were high from 5 a.m. to 6 a.m. and decreased through the day only to peak again at 7 p.m. Stereotypic pacing peaked at dawn and at dusk. Patterns of vigilance, feeding, and maintenance were also determined for the group during a 24-hr period. These results may be useful for the development of management plans and effective conservation strategies for captive cats.     

Activity Patterns, Intergroup Encounters, and Male Affiliation in Free-Ranging Bearded Sakis (Chiropotes sagulatus)

The assessment of how primates divide their daily activities is one of the foundations of primate behavioral ecology but the activity patterns and social behavior of the Pitheciines, including bearded sakis (genus Chiropotes), are poorly understood. During a 15-mo study, I collected 560 h of data on subgrouping, activity patterns, social behavior, and intergroup encounters of a group of free-ranging Guianan bearded sakis (Chiropotes sagulatus) in Guyana. The study group consisted of at least 65 individuals but showed a high degree of flexibility in grouping patterns (mean group size 39 ± 10). They were highly active, spending ca. 70% of their diurnal activity budget traveling and feeding. Activity patterns were relatively consistent throughout the year, although time spent feeding correlated significantly with fruit availability. The most common social behaviors were social resting and grooming. Agonism was rare (2.56% of social behavior) but did occur in the context of intergroup encounters, with males from the same group cooperating in intergroup agonism. Bearded sakis showed a high level of within group male affiliation, with male–male partners making up 65% of grooming dyads and males having another male as their nearest-neighbor 66% of the time. These results show that bearded sakis are characterized by egalitarian male–male and male–female relationships, highly fluid group sizes, and high levels of male affiliation. Similarities in the social behavior of bearded sakis and muriquis suggest several possible explanations for male–male bonding including cooperative defense of females from other groups, kinship, and maintenance of social cohesion after subgroup coalescence.     

Activity budgets of wild female chimpanzees in different reproductive states

Activity budgets of wild female chimpanzees (Pan troglodytes schweinfurthii) when lactating were compared with those during estrus and anestrus. Five anestrous females, seven estrous females, and three lactating females in Mahale Mountains National Park, Tanzania, were the subject of focal sampling. Time spent for feeding, resting, and moving was examined. For each of these three categories of activity, there was no significant difference of time spent for each activity between lactating females and either estrous or anestrous females. The females spent about 30% of their daytime feeding, about 40% resting, and about 30% moving. One of the reasons for the lack of difference might be the type of parties that females attended when they were observed. In most cases, the females were seen in large bisexual parties. Although lactating females are expected to need more nutrition than cycling females and this might affect their activity budget, the party type they attended might also affect the budget. Received: January 17, 2000 / Accepted: June 22, 2000     

The ecology of motherhood: the structuring of lactation costs by chacma baboons

1. Data from a long-term study of Papio hamadryas ursinus (L.) in the De Hoop Nature Reserve, Western Cape, South Africa, were used to test the assumptions and predictions of Altmann's model of maternal time budgets. 2. Female baboons' feeding time was below model predictions, and there was no evidence for a consistent increase in feeding time with infant age. In addition, female feeding time was not significantly higher than observed baseline feeding times for nonlactating females. 3. Female baboons reduced activity levels in the first few months post-partum, as reflected in significant increases in resting time, and there was some indication that females lost body mass over the course of lactation. When feeding demand was high, females sacrificed social time, and conserved resting time. 4. Females increased vigilance levels during the first 4 months of infant life and were more vigilant overall during lactation than when nonlactating. There was a negative relationship between feeding time and vigilance, but a positive relationship between resting time and vigilance. 5. Female baboons at De Hoop appear to cope with the energetic costs of lactation by reducing activity levels, although this cannot compensate completely for increased energetic costs. This may not be so much an'energy-sparing' strategy as a response to threats presented by infanticidal males in this population. Females therefore trade-off feeding time against vigilance.     

Enclosure environment affects the activity budgets of captive Japanese macaques (Macaca fuscata)

Individuals adapt to changes in their environment, such as food availability and temperature, by adjusting the amount of time spent in different behavioral activities. These adjustments in behavior should vary across age-sex class according to specific physiological and social needs. We studied the activity budgets of three social Japanese macaque groups inhabiting either vegetated or nonvegetated enclosures in order to compare the effects of access with vegetation, as both food and substrate on resting, feeding, grooming and moving activities over a 12-month period. Daily access to natural foods for monkeys in the vegetated enclosure seems to be largely responsible for the differences in daily time budgets of these three groups. Resting time in all three groups was longer than the time devoted to other activities. Resting and moving time in the two nonvegetated enclosures was significantly longer than in the vegetated enclosure. In contrast, feeding and grooming time was significantly longer in the vegetated enclosure. Seasonal variation in time spent feeding, resting and grooming was significantly effected by enclosure type. In all three enclosures, immatures, particularly females, spent more time feeding and moving, whereas adults spent more time resting. Significant monthly variation in time spent by age-sex class was noted only for feeding and resting. Interestingly, in the vegetated enclosure, time spent feeding on natural vegetation was equal to the amount of time spent feeding on provisioned food. This suggests that factors other than energetic and nutritional needs may be important determinants of the activity budget of the species. These results have important implications for the enrichment of captive primates and our understanding of the maintenance of activity patterns by primates in the wild.     

广西扶绥黑叶猴活动节律和日活动时间分配

2002 年8 月至2003 年7 月,对生活在完全被周围农田隔离的石山中的一群黑叶猴的昼夜活动节律和日活动时间分配进行研究。采用以群为单位的焦点动物观察法和连续记录法,每月对猴群连续10 d 跟踪观察。结果表明:3 月至10 月,黑叶猴的昼夜活动节律由8 个环节组成,11 月至2 月由9 个环节组成,移动、觅食和休息在活动节律中重复出现,晒太阳仅出现在11 月至翌年2 月。休息占黑叶猴日活动时间的比例最大,其次是觅食、移动、晒太阳和理毛。黑叶猴的日活动时间分配具有明显的月变化规律,相关性分析表明,环境温度、栖息地的食物丰富度和光照强度是影响黑叶猴日活动时间分配的主要因素。进一步分析认为,黑叶猴的活动时间分配体现了叶食性灵长类的特点,更体现了黑叶猴对北热带喀斯特石山环境的适应特点。     

Seasonal Variation in the Activity Patterns and Time Budgets of <Emphasis Type="Italic">Trachypithecus francoisi</Emphasis> in the Nonggang Nature Reserve,China

Activity patterns and time budgets are 2 important aspects of animal behavior that researchers use to investigate ecological influences on individual behavior. We collected data on activity patterns and time budgets in 1 group of François’ langurs (Trachypithecus francoisi) from August 2003 to July 2004 in the Nonggang Nature Reserve, Guangxi Province, China, via instantaneous scan sampling method with 15-min intervals. The diurnal activity pattern of François’ langurs showed morning and afternoon feeding peaks, with a midday resting peak. Seasonal change was apparent in the activity pattern: 2 significant feeding peaks occurred in the dry season and only 1 significant feeding peak in the rainy season. The group spent an average of 51.5% of the daytime resting. Feeding and moving accounted on average for 23.1% and 17.3% of the activity budget, respectively. Subjects spent little time on social activities, averaging 2% for grooming and 5.5% for playing. Their time budgets showed significant seasonal variation: they spent a greater proportion of time on feeding and less time on resting and grooming in the dry season than in the rainy season. They also differed among different sex-age classes: immatures spent more time playing, whereas adults devoted more time to resting, feeding, and grooming. Correlations between time budgets and food items or food availability clearly indicated that François’ langurs might adopt an energy-maximizing strategy when preferred foods were scarce in the dry season.     

白马雪山自然保护区响古箐滇金丝猴活动时间分配

2008 年6 月至2009 年5 月,在白马雪山国家级自然保护区南端的响古箐(北纬27°37′,东经99°22′),采用瞬时扫描取样法对一群数量约480 只的滇金丝猴群的活动时间分配进行了研究。研究期间共观察取样1 609 h,扫描个体数为260 546。研究表明,响古箐滇金丝猴用38.8% 的时间取食、27. 4% 的时间移动、20. 9%的时间休息、12.9% 的时间从事其他类型活动。滇金丝猴活动时间分配季节性差异明显。冬季,滇金丝猴的取食时间长于其他季节,达到41. 5% ;秋季,取食时间在全年最短(36.5% )。夏季的高温没有影响滇金丝猴的移动,它们移动的时间达到32.8% ,高于其他3 个季节。寒冷的冬季,响古箐滇金丝猴为了减少能量损失,用于休息的时间达到24.4% 。秋季,滇金丝猴从事其他类型活动的时间(15.7% )多于另外3 个季节。研究发现,
绝对移动时间与昼长和月平均温度呈明显正相关(P < 0. 01),绝对休息时间与月平均温度呈负相关(r =- 0. 585,P = 0.046),但降水量的多少与猴群各种活动时间分配之间没有明显的相关性(P > 0.05)。食物贡献率与滇金丝猴日活动时间分配也存在相关性。取食松萝比例与猴群移动时间呈负相关(r = - 0.902,P <0.001),与休息时间呈正相关(r = 0.860,P < 0.001)。猴群取食树叶比例增加时,它们移动时间也随之增加(r = 0.832,P = 0.001)。夏季,滇金丝猴取食竹笋的比例增加时,猴群移动时间也明显增多。以上结果表明,滇金丝猴活动时间分配受食物资源状况、昼长季节性变化和气候条件的影响。     

Costs of twins in free-ranging white-bellied spider monkeys (Ateles belzebuth belzebuth) at Tinigua National Park, Colombia

A female spider monkey (Ateles belzebuth belzebuth) that gave birth to twins was studied during 13 months, and her activity budget and diet were compared to those of females with single offspring and females with no offspring to assess selective pressures that could influence litter size. We recorded qualitative information on the development and social interactions of the twins and three other single infants. Emi, the female that had the twins, had the highest proportion of resting time and the lowest proportion of feeding and moving time compared to other adult females and males. Emi also had the lowest average daily travel distance and relied more heavily on flowers and leaves than other group members who included a higher proportion of fruits in their diets. These results suggest that twins are energetically costly to spider monkeys because of the direct energy allocated into raising and carrying the twins and, also, because these costs have direct effects in the ability of a mother to obtain high-quality resources (e.g., fruits). The twins had a slower rate of physical and social development as well as a smaller body size compared to same-aged singletons by the end of the study. Thus, the extended periods of maternal care and the costs associated with rearing and carrying offspring are some of the factors that influence the evolution and maintenance of a litter size of one in most anthropoid primates.     

The activity budgets and activity patterns of sympatric grey rhebok and mountain reedbuck in a highveld grassland area of South Africa

Behavioural observations were carried out on grey rhebok and mountain reedbuck at Sterkfontein Dam Nature Reserve, South Africa, for a period of 1 year between May 2001 and April 2002. Four harem herds of grey rhebok, five territorial male mountain reedbuck and female mountain reedbuck (herds grouped as one individual) were monitored to determine activity budgets and activity patterns. Both species spent more time feeding in the late afternoon during relatively cool temperatures, and more time resting in the middle of the day during relatively high temperatures. Statistical comparisons between the two species of the percentage time feeding and resting found no differences between them, although mountain reedbuck spent more time resting overall than grey rhebok. Both species were active at night.