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Hindawi International Journal of Zoology Volume 2022, Article ID 8107527, 12 pages https://doi.org/10.1155/2022/8107527 Research Article The Activity and Ranging Patterns of Gelada Monkeys as Behavioral Responses to the Effects of Livestock Grazing in the Simien Mountains National Park, Ethiopia 1 2 2 Belayneh Abebe , Mezgebu Ashagrie, and Eshetu Moges Simien Mountains Landscape Conservation and Management Project, African Wildlife Foundation, Debark, Ethiopia Department of Wildlife and Ecotourism Management, College of Agriculture and Environmental Sciences, Bahir Dar University, Bahir Dar, Ethiopia Correspondence should be addressed to Belayneh Abebe; firstname.lastname@example.org Received 27 January 2022; Revised 2 July 2022; Accepted 14 September 2022; Published 5 October 2022 Academic Editor: Irene Pellegrino Copyright © 2022 Belayneh Abebe et al. �is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Understanding of behavioral ecology of primates in grazed lands is vital to their conservation and monitoring strategies. Here we investigated how livestock grazing within the Simien Mountains National Park a†ects the activity time budgeting and ranging behavior of the geladas, a monkey endemic to Ethiopian highlands. �is study was carried out from February 2019 to July 2019 by stratifying the study area as grazed and nongrazed sites. Activity time pattern data were collected using 5 minutes instantaneous scan sampling within 15 minutes intervals from 7:00 to 18:00 for 10 days per month in the grazed and nongrazed sites. �e ranging data were also collected by tracking the study group and recording GPS points every 15 minutes sample. �e e†ects of livestock grazing on activity time budgets were statistically analyzed by multiple analyses of variance (MANOVA). Daily range length and home range size were estimated by employing the Open Jump toolbox (MOVEAN), and statistically tested by Mann–Whitney U test. From 3427 behavioral scans on the various activities, feeding was the most frequent (43.04%) behavioral activity followed by moving, accounting for 38.06% of the time. �e study revealed that grazing has a statistically signi¡cant e†ect on moving and social activity time budgets. �e geladas dwelling in the grazed areas of the park spent more time in moving than in the nongrazed areas. �e e†ect of grazing on social behavior is the reverse of moving. Similarly, geladas traveled longer daily range length and cover a wider home range size in the grazed areas. �erefore, these ¡ndings of the study imply that livestock grazing is adversely a†ecting the behavior of gelada monkeys in the park. To minimize such e†ects on gelada monkeys and harmonize grazing with wildlife habitat conservation, the grazing pressure reduction strategy must be closely monitored and supported by animal feed cultivation technology. same habitat as livestock for grazing. Consequently, they 1. Introduction compete for the same resources. Livestock grazing has been �e gelada (eropithecus gelada) is a dominantly grass- destroying the habitats of wildlife and this has resulted in a eating primate dwelling in the highlands of Ethiopia . lack of enough ranging space, food, and other resources for Afroalpine plateau areas are intensively livestock grazed, and the conservation of wildlife species . this has already a†ected both biodiversity and ecological Activity budgets of primates are in¦uenced by many processes through soil and vegetation degradation of the factors in natural habitats, most of which relate to the habitats . Increasing livestock and human population challenges of acquiring food energy and the availability of pressure coupled with inappropriate land use has led to food resources [4, 5]. For instance, the decline of wildlife massive destruction of wildlife habitats and reduction in the habitat quality [6–8] includes a reduction of perennial grass wildlife population. Wild animals including geladas use the and herbaceous vegetation covers [9, 10]. �erefore, factors 2 International Journal of Zoology time spent traveling and/or foraging time, day range; or that inﬂuence food availability have a strong eﬀect on time allocation decisions [11, 12]. increasing traveling and/or foraging time, day range length, and home range size and sacriﬁcing their social time [25, 26]. Livestock grazing is an inﬂuential driver of plant pop- ulation dynamics and community succession. Some pri- )erefore, this study was initiated to examine how gelada mates change their behavioral patterns in response to the monkeys behaviorally respond to their activity time budget integrated eﬀect of grazing with seasonal variations on the and ranging pattern to cope with the livestock grazing availability, relative abundance, and distribution of food competition pressure in either of the above-stated plant species [13, 14]. hypothesis. Variations of habitat preferences and movement pat- terns in primates have been much discussed related to 2. Methods ecological factors [15–17]. )ere have been relatively few attempts to measure and distinguish resource availability 2.1. Study Area. )e Simien massif in Ethiopia is an ex- related to livestock grazing and other variables aﬀecting the traordinary landscape, with endless vistas and rare, endemic habitat selection of geladas. However, studies on the be- wildlife species including gelada monkey. )e Simien havioral ecology of geladas have been limited and few in Mountains have been home to human settlers for thousands Simien Mountains (Sankaber: [15, 18, 19], Gich: [20, 21] and of years . )e Simien Mountains National Park (SMNP) Chennek: ) and some of them have looked at grazing is found in the northwestern Amhara Region of Ethiopia. eﬀects. Nevertheless, this has been done by comparing re- )e park is found within ﬁve Woredas: Debark, Adarkay, sults across studies in diﬀerent areas . )erefore, this Beyeda, Janamora and Telemt, bordering 42 kebele of these research looked at the eﬀects of grazing within the Simien Woredas . )e Park is an area of great diversity and Mountains National Park. scenic beauty that was established in 1966  and currently Behavioral responses to grazing pressure remain covers an area of 412 km . )e presence of unique landscapes undescribed despite the fact that this information is critical and a wide range of ﬂora and fauna with the high level of for the establishment and implementation of eﬀective endemism made SMNP a World Heritage Site in 1978. management and conservation plans for this species. In However, 18 years later, in 1996, the SMNP ﬁgures on the addition, behavioral patterns of a primate species do not List of the World Heritage in Danger mainly due to the always show a consistent pattern [15, 19, 23]. )is may be declining key species population. In just a few years, the due to the ability of diﬀerent species to cope with resource ecosystem has rebounded and wildlife populations have scarcity and feeding competition in diﬀerent ways. rallied . After 21 years of collaborative eﬀort to reducing Determining the activity patterns of the geladas in re- the grazing pressure and increment of the declined wildlife sponse to human disturbances is an important step to un- population, UNESCO removed the park from the list of derstand how human impacts on the environment can shape World Heritage in Danger in 2017 . primate ecology and evolution . Similarly, an under- )e park harbors four endemic large mammals of standing of the basic natural history of primate species is Ethiopia: Walia ibex (Capra walie), Ethiopian wolf (Canis vital to their conservation, particularly examining the in- simensis), Menelik’s bushbuck (Tragelaphus scriptus mene- terface of gelada behavioral ecology with competing live- liki), and Gelada monkey ('eropithecus gelada) and are the stock in human-altered habitats . For instance, data on ﬂagship species of SMNP . Moreover, the Simien activity patterns of primates provides an insight into eﬀects Mountains are characterized by a high level of plant en- of livestock grazing on their behavioral pattern and ﬂexi- demism and are part of the Eastern Afromontane hotspot of bility on such anthropogenic alteration. Furthermore, data plant diversity. Furthermore, Simien Mountains are central on activity patterns is important to seek management so- to the botanical history of Ethiopia . lutions for the negative eﬀects of grazing pressure on the gelada habitats and can help to guide monitoring strategies for threatened primate species. Besides, it can be an input for 2.2. Study Site and Sampling Design. Sites of the Simien further studies on the interface of wildlife conservation with Mountains National Park were stratiﬁed into sites where livestock production. In line with this, recently the Simien livestock grazing is allowed and sites where grazing is strictly Mountains have been subjected to ﬂuctuations over time in forbidden. Chennek, Sankaber, Gich, SebatMinch, RasDe- the type and amounts of food that are available for wild jen, and KidusYared are protected from grazing whereas animals due to livestock grazing and management inter- Aynameda, Limalimo, Aterie, Abarie, Arkwaziye, Michiby, ventions (personal observation). Under these varying con- and Silki are under intense grazing. To minimize the eﬀect of ditions, the resulting changes in vegetation composition and bio-physical natural diﬀerences of the sampling sites on the cover are expected to alter environmental conditions for a study's expected results, geographically adjacent sites, San- variety of wildlife species. Furthermore, to help the con- kaber (nongrazed site) and Michiby (grazed site) were se- servation of a ﬂagship species like geladas, wildlife managers lected. In the 2019 monitoring report of the park, a total of need to have much more information on their habitat re- 6,287 livestock was estimated in Michiby. Shoats was the quirements and their behavioral adaptability to the changes most frequently encountered and most abundant (N) live- in habitat qualities. During times of food scarcity, it is stock type followed by cattle and lastly equines. An estimated hypothesized that primates may adapt to this situation in 1.3 TLU’s per hectare were found in this area, almost three two alternative behavioral responses either by decreasing times higher than the recommended 0.5 TLU’s per hectare International Journal of Zoology 3 whether they fulﬁlled the assumptions of parametric tests or for highland ecosystems. In addition, the report indicates that variation across seasons were observed, 1.3 and 1.5 not. Nonparametric tests were used for the data that did not fulﬁll the assumptions. Level of statistical signiﬁcance was set TLU’s per hectare were found in the dry and wet season, respectively . Detailed descriptions of these sites are at P � 0.05 for all analyses. found in Dunbar , Hunter , and Jarvey et al. . For To examine the eﬀect of grazing level on the activity time this behavioral ecology study, nine one-male units (OMU) budget of diﬀerent behavioral responses (feeding, social, were taken as focal groups dwelling in grazed and nongrazed resting, moving, and other) one-way Multivariate Analysis sites of the SMNP (Figure 1). Detailed behavioral and of Variance (MANOVA) was used. Pearson correlation ranging data were collected from all adult males and females analyses were also used to assess relationship between the in these nine one-male units (N = 73 females, and 48 males). time budget of diﬀerent behavioral activities and activity )e geladas in this population have been fully habituated to time adjustments of the gelada monkeys to cope with constraints due to the grazing eﬀect. Additionally, the eﬀects human observers on foot at a distance of 2m and were individually recognizable by natural markings. of grazing levels on daily travel distance were analyzed using Mann–Whitney U test. 2.3. Behavioral Data Collection and Analysis 3. Results 2.3.1. Activity Pattern. Activity patterns of geladas in the 3.1. Activity Budget. A total of 3427 behavioral scans on the Sankaber and Michiby areas were collected from Feb 2019 to various activities were recorded throughout the study pe- Jul 2019 (with the exception of April 2019, when no data riod. Feeding was the most frequent behavioral activity from were collected because of a massive ﬁre blaze in the Simien the overall activity budget (Figure 2), which contributed to Mountains). Data collection covered parts of the wet and dry 43.04% of the time gelada spent on the ﬁve main activities seasons with an average of 10 days per month. In particular, recorded. Moving was the next most common activity, 5 minutes instantaneous scan samples were used at 15-min accounting for 38.06% of the time. Socializing contributed intervals  from 07:00 hr to 18:00 hr to determine the 11.52% of the time. Resting and others were the least percentage of time allocated to various activities of the common activity, accounting for 6.40% and 0.98% of the sample gelada groups. During the scan sampling, among all time respectively (Figure 2). visible individuals of the study group, nine (n � 9) were sampled, to record their behaviors: feeding, moving, resting, socializing, and others on the standardized data sheet [15, 3.1.1. Diurnal Activity Pattern and Inﬂuence of Grazing. 34]. During the study period, 1926 behavioral observations on )e percentage of time budget spent on various activities the various activities were recorded in nongrazed, and 1501 was calculated for each day. Data obtained from all scans behavioral observations were recorded in grazed areas from were ﬁrst pooled for each daily sample to estimate the daily 9 OMUs. Feeding and moving were peaks throughout the activity time pattern in the grazing categories. )en the daily day in grazed areas (Figure 3). However, feeding activity basis pooled activity time budget was statistically analyzed indicated an increasing trend during the late morning (10: for testing the eﬀects of grazing on the activity time of 00–11:00 h) and towards the end of the early afternoon (17: geladas. 00–18:00 h); and moving was almost constant throughout the day in nongrazed areas (Figure 4). Social activities were peak from 8:00–10:00 h in grazed and nongrazed areas, but a 2.3.2. Ranging Patterns. At the time of each scan sample, the slightly higher proportion was observed in nongrazed areas. geographic center of the group was recorded using a Garmin Geladas spent almost equal time feeding GPS at 15 minute intervals from 07:00 hr to 18:00 hr during (43.42%± 8.96%) in nongrazed and grazed areas the sampling days mentioned above. )e collected GPS data (42.63%± 6.87%). However, the time spent in moving was were converted into shapeﬁles, and the daily travel distance higher in grazed than in nongrazed areas, which contributed and home range size were estimated using Open Jump 42.68%± 5.96% and 33.66%± 7.20% of the time, respec- (animal movement analysis GIS application) . tively. Resting time was higher in nongrazed areas )e daily range length of the sample group was estimated (7.10%± 4.99%) than in grazed areas (5.71%± 4.59%). Social from the track of point-to-point movements of the group activities were higher (14.92%± 8.29%) in nongrazed areas between consecutive GPS points. Home range size was es- than in grazed areas (7.93%± 5.97%) and other activities timated using 95% minimum convex polygon (MCP) were less in nongrazed (0.93%± 1.34%) than in grazed areas method [4, 16, 36, 37]. For the home range size estimation, (1.04%± 1.63%) (Figure 5). all daily ranges data were combined on a seasonal scale and A statistical test showed grazing levels have a signiﬁcant grazing levels. Total home range size was also determined for eﬀect on the diﬀerences in the behavior of gelada (feeding, each group based on the total locations recorded . moving, resting, social, and others). )e result of the analysis makes clear that grazing level has a statistically signiﬁcant 2.4. Statistical Analysis. All statistical analyses were per- eﬀect on activity time budget, F = 11.04, P< 0.001, [4,73] formed using SPSS statistical software version 20 (SPSS Inc. Wilks’ Λ = .62, partial η = 1.0. )is high eﬀect size (partial Chicago, IL, USA). All data were assessed to determine η = 1.0)] implies, grazing level has a strong eﬀect on changes 4 International Journal of Zoology 13.2519 13.2433 13.2348 13.2263 13.2177 13.2092 13.2007 13.1921 13.1836 37.9984 38.0119 38.0254 38.0389 38.0524 Figure 1: Sampling sites of the study. 50.00 40.00 43.04 38.06 30.00 20.00 10.00 11.52 6.40 0.98 0.00 Feeding Moving Resting Social Other Activity catagory Figure 2: Activity time budget of geladas. in the activity time budget of diﬀerent behavior between η = 0.32) and social activity time budget (F = 18.06; [1,76] grazed and nongrazed areas (Table 1). )erefore, livestock P< 0.001; partial η = 0.19). Eﬀect sizes of statistical tests grazing signiﬁcantly inﬂuences the activity time budgets of revealed social behavior and moving were highly inﬂuenced gelada monkeys in Simien Mountains National Park. by grazing level compared to other activities. However, eﬀect Particularly, grazing level has a statistically signiﬁcant of grazing level on the time spent in feeding (F = 0.19, [1,76] eﬀect on both moving (F = 36.06; P< 0.001; partial P � 0.66, partial η2 = 0.002); resting (F = 1.57, P � 0.21, [1,76] [1,76] Time spent % International Journal of Zoology 5 60.00 50.00 40.00 30.00 20.00 10.00 0.00 ACTIVITY TIME Feeding Resting Moving Social Other Figure 3: Daily activity pattern in grazed areas. 60.00 50.00 40.00 30.00 20.00 10.00 0.00 ACTIVITY TIME Feeding Resting Moving Social Other Figure 4: Daily activity pattern in nongrazed areas. partial η = 0.02) and other (F = 0.12, P � 0.73, partial time spent on other activities was weakly positively corre- [1,76] η = 0.002) was not statistically signiﬁcant (Table 1). lated with moving (r = 0.234, P � 0.039). In contrast, time Pearson correlation analysis in Table 2 demonstrated spent on other activities was weakly negatively correlated with the social activity budget (r = −0.25, P � 0.027). that the proportion of time spent in resting and socializing was strongly negatively correlated with feeding (r = −0.631, P � 0.001 and r = −0.597, P � 0.001) respectively. Resting 3.2. Ranging Behavior. )e mean daily travel distance of the and socializing were also strongly negatively correlated with moving (r = −0.524, P � 0.001 and r = −715, P � 0.001) re- focal group over the entire course of the study was 1474.05± 1100.38 m (Figure 6). )e minimum and maxi- spectively. Nevertheless, feeding was not correlated with moving (r = −0.011, P � 0.924). On the other way, resting mum Monthly mean daily distances traveled by the group were 1141.83± 289.1 m (June) and 1903.69± 2017.1 m time was positively correlated with social time (r = 0.590, P � 0.001). )e proportion of time spent on other activities (March), respectively. However, the diﬀerence in mean daily travel distance between seasons was not signiﬁcant (U � 277, was not correlated with feeding (r = −0.041, P � 0.718) and P � 0.13). resting (r = −0.216, P � 0.058). However, the proportion of PERCENTAGE PERCENTAGE 7:00-8:00 7:00-8:00 8:00-9:00 8:00-9:00 9:00-10:00 9:00-10:00 10:00-11:00 10:00-11:00 11:00-12:00 11:00-12:00 12:00-13:00 12:00-13:00 13:00-14:00 13:00-14:00 14:00-15:00 14:00-15:00 15:00-16:00 15:00-16:00 16:00-17:00 16:00-17:00 17:00-18:00 17:00-18:00 6 International Journal of Zoology 50.00 45.00 40.00 35.00 30.00 25.00 20.00 15.00 10.00 5.00 0.00 Feeding Moving Resting Social Other Activity catagory Non Grazed Grazed Figure 5: Comparison of activity time budget between the nongrazed and grazed areas. Table 1: Multivariate analysis result. Multivariate Tests Hypothesis Partial eta Noncent. Observed Eﬀect Value F Error df Sig. df squared Parameter power Pillai’s trace 1.000 90064.828 4.000 73.000 0.000 1.000 360259.311 1.000 Wilks’ lambda 0.000 90064.828 4.000 73.000 0.000 1.000 360259.311 1.000 Hotelling’s Intercept 4935.059 90064.828 4.000 73.000 0.000 1.000 360259.311 1.000 trace Roy’s largest 4935.059 90064.828 4.000 73.000 0.000 1.000 360259.311 1.000 root Pillai’s trace 0.377 11.049 4.000 73.000 0.000 0.377 44.195 1.000 Wilks’ lambda 0.623 11.049 4.000 73.000 0.000 0.377 44.195 1.000 Hotelling’s Grazing_Level 0.605 11.049 4.000 73.000 0.000 0.377 44.195 1.000 trace Roy’s largest 0.605 11.049 4.000 73.000 0.000 0.377 44.195 1.000 root Tests of between-subjects eﬀects Dependent Type III sum of Partial eta Noncent. Observed Source df Mean square F Sig. variable squares squared Parameter power Feeding 12.056 1 12.056 0.187 0.666 0.002 0.187 0.071 Moving 1583.432 1 1583.432 36.063 0.000 0.322 36.063 1.000 Corrected Resting 36.077 1 36.077 1.567 0.214 0.020 1.567 0.235 model Social 950.498 1 950.498 18.061 0.000 0.192 18.061 0.987 Other 0.267 1 0.267 0.116 0.734 0.002 0.116 0.063 Feeding 144314.298 1 144314.298 2244.316 0.000 0.967 2244.316 1.000 Moving 113596.529 1 113596.529 2587.192 0.000 0.971 2587.192 1.000 Intercept Resting 3178.161 1 3178.161 138.035 0.000 0.645 138.035 1.000 Social 10176.748 1 10176.748 193.378 0.000 0.718 193.378 1.000 Other 75.735 1 75.735 32.918 0.000 0.302 32.918 1.000 Feeding 12.056 1 12.056 0.187 0.666 0.002 0.187 0.071 Moving 1583.432 1 1583.432 36.063 0.000 0.322 36.063 1.000 Grazing_Level Resting 36.077 1 36.077 1.567 0.214 0.020 1.567 0.235 Social 950.498 1 950.498 18.061 0.000 0.192 18.061 0.987 Other 0.267 1 0.267 0.116 0.734 0.002 0.116 0.063 Time spent % International Journal of Zoology 7 Table 1: Continued. Feeding 4886.962 76 64.302 Moving 3336.952 76 43.907 Error Resting 1749.849 76 23.024 Social 3999.589 76 52.626 Other 174.854 76 2.301 Feeding 149375.956 78 Moving 117904.460 78 Total Resting 4983.579 78 Social 15293.755 78 Other 250.676 78 Feeding 4899.018 77 Moving 4920.384 77 Corrected total Resting 1785.926 77 Social 4950.086 77 Other 175.121 77 a b c a b Design: intercept + grazing level. Exact statistic. Computed using alpha � 0.05., R squared � 0.002 (adjusted R squared � −0.011). R squared � 0.322 c d e (adjusted R squared � 0.313). R squared � 0.020 (adjusted R squared � 0.007). R squared � 0.192 (adjusted R squared � 0.181). R squared � 0.002 (adjusted R squared � −0.012). Computed using alpha � 0.05. Feb Mar May Jun Jul Months Grazed Non Grazed Figure 6: Monthly mean of daily travel distances (m) for the study group across grazing level. In contrast to season, grazing levels have a signiﬁcant respectively (Table 3). )e focal groups in the grazed area eﬀect on daily range length (U � 31, P< 0.001). )e esti- extended their home range than the focal groups in non- mated average day range length of gelada in the grazed areas grazed area as a result of seasonal changes (Figure 7). was 2024.89± 977.13 m, whereas that of the nongrazed areas was 1085.02± 141.97 m. In the grazed areas, the minimum 4. Discussion and maximum range lengths were 1085.60 and 5170.43 m, respectively. )e longest daily range length in the nongrazed 4.1. Activity Time Budget. Time spent on diﬀerent activities areas was 1419.32 m, and the shortest was 849.33 m. in animals is an indication of balancing the energy budget )e home range size of the focus groups was wider for various activities. Many factors are known to inﬂuence (3.03 km ) in grazed area than in the nongrazed area the activity budgets of primates, most of which are associated (1.74 km ). During the dry season, the focal groups used with the challenges of acquiring suﬃcient food energy . 2 2 2.91 km and 1.45 km in grazed and nongrazed areas, re- Variations in the timing of daily activity patterns are 2 2 spectively. However, 1.74 km and 1.26 km were used characteristics of primates . )e daily activity pattern of during the wet season in grazed and nongrazed areas, re- gelada’s was signiﬁcantly diﬀerent at diﬀerent grazing levels spectively. )e home range size of the geladas over the study over the daytime. period was varied seasonally and across grazing levels. Analysis of daily activity patterns of gelada demonstrated Seasonal overlap of home range use was observed in both that feeding and moving peaks throughout the day in grazed 2 2 grazed areas and nongrazed areas 1.67 km and 0.98 km areas. Nevertheless, feeding activity indicated an increased Daily travel distance (m) 8 International Journal of Zoology Table 2: Pearson correlation coeﬃcients for diﬀerent activity categories. Activity time Moving Resting Social Other ∗∗∗∗ ∗∗ r −0.011 −0.631 −0.597 −0.041 Feeding P 0.924 0.000 0.000 0.718 ∗∗ ∗∗ ∗ r — −0.524 −0.715 0.234 Moving P 0.000 0.000 0.039 ∗∗ r — 0.590 −0.216 Resting P 0.000 0.058 r — −0.250 Social P 0.027 ∗∗ ∗ Correlation is signiﬁcant at the 0.01 level (2-tailed). Correlation is signiﬁcant at the 0.05 level (2-tailed). 1.5 0.75 0 1.5 Kilometers UngrazedDry Grazed Wet UngrazedWet Non Grazed Grazed Dry Grazed Figure 7: Depiction of the 95% minimum convex polygon (MCP) of seasonal home ranges of the study groups in grazed and non-grazed areas. pattern during the late morning and towards the end of the Prioritization of time allocation for feeding is in accor- early afternoon . Conversely, Barrett , reported that dance with the results of other gelada studies by Hunter feeding activity in a diﬀerent primate species might be , and Iwamoto and Dunbar . )e reason for such a peaked at the beginning of the day. Among the daily activity high proportion of time devoted to the feeding activity patterns, moving did not show signiﬁcant variation across may be due to the geladas’ high degree of dietary spe- the daytime. Similarly, Woldegeorgis and Bekele , cialization on grasses, which may have lower nutritional conﬁrmed that moving was almost higher throughout the quality . )e bulk feeding strategy of gelada requires a day as compared to the other behavioral activities. Social very large proportion of their time to be dedicated to activities peaked from 8 : 00–10 : 00 h in grazed and non- feeding over other activities. Iwamoto and Dunbar , grazed areas but a slightly higher proportion was revealed in have also stated that better habitat quality is associated nongrazed areas. Woldegeorgis and Bekele  also re- with decreased feeding and increased resting among gelada ported that socializing and resting activities peaked during groups. the early morning hours, probably due to the presence of On the other hand, the time allocated for moving was animals in their home range. However, resting and social higher in the grazed area (42.68%) than in nongrazed activities peaked over the midday hours for other primates (33.66%) area. Factors that aﬀect food availability have a . strong inﬂuence on time allocation decisions for diﬀerent Geladas spent almost similar time feeding (43.42%) in behavioral activities [34, 43, 44]. In this regard, it is predicted that since traveling is an energetically costly activity, the nongrazed and grazed (42.63%) areas. )e present study has shown that the activity budgets of gelada generally reduction of time spent in moving is expected as an energy- resemble those of geladas studied at other sites [12, 15, 20]. saving strategy to cope up with the resource limitations in International Journal of Zoology 9 Table 3: Home range of geladas across grazing level and season. 2 2 Season Nongrazed (km ) Grazed (km ) Dry 1.45 2.91 Wet 1.26 1.74 Seasonal overlap 0.98 1.67 Overall 1.74 3.03 food scarce conditions . In contrast to this, to acquire previous study [45, 50]. )e longer daily travel distance of suﬃcient food energy geladas spent more time for moving in the group may reﬂect increased foraging eﬀort, due to search of food in a site constrained by grazing pressure. )is disturbed conditions of the area and thus low resource is also supported by the foraging strategy of primates availability [15, 36, 51]. In contrast, Iwamoto and Dunbar , Hunter , Abu , and Kiﬂe et al.  noted that adapted to feed on relatively low nutritious and available food items like grass and corms . geladas move for only a short distance a day, which is 0.8–1.56 km, compared to other baboons and with the In contrast to the eﬀect of grazing on moving, the social time was reduced in the grazed area (7.93%) than in the present study. )ese might be associated with the variations in food availability and band size in the respective study area nongrazed area (14.92%). In addition to the eﬀect of grazing on moving, the social behavior of gelada is negatively and period of study. inﬂuenced. However, the time allocated for resting is not )e home range size of geladas varied among grazing inﬂuenced by grazing. )is result agrees with Dunbar  levels in the study area. )e variations of resources in Simien and Alberts et al. , who suggested that ecologically Mountains National Park in the grazed and nongrazed areas stressed geladas might reduce social times for increased had an impact on the ranging behavior of geladas. )e feeding time under poor ecological circumstances. )is present study revealed that the home range size of the geladas in grazed areas was wider (3.03 km suggestion is in accordance with the present ﬁnding indi- ) than in non- cating a signiﬁcant negative correlation of time budget for grazed areas (1.74 km ). )e larger home-range size of the social behavior with feeding and moving. In the grazed site, focal group in grazed areas was primarily related to the the feeding and moving time of geladas were higher, but overall low availability of green grass and other resources in their social time was lower. )us, gelada monkeys in SMNP the study area. In the grazed areas of the park, geladas were followed a dispensable social time strategy to adapt to the constrained by grazing competition due to livestock grazing adverse eﬀects of livestock on their behavior. Indeed, such which aﬀects the habitat quality and above-ground biomass. behavioral adaptations might be observed when the gelada As a result, geladas move from one patch of land to the other monkeys face competition for food with other grazer wild and increased home range size in disturbed areas . Kiﬂe animals dwelling in the park which is not considered our et al.  have also reported variations in the extent of home ﬁeld study. range of geladas between habitats because of human-in- duced activities. In addition to anthropogenic inﬂuence, seasonal varia- 4.2. Ranging Pattern. )e results of this study indicate that tion has the inﬂuence to widen or narrow the home range of geladas adjust their ranging length in response to grazing the gelada over the study period. Abu , Kiﬂe et al.  level. Daily ranging behavioral response depends on how and Moges  have also reported variations in the extent of much travel time would need to increase while maintaining the home range of geladas between seasons. Hunter  and the energy requirement of the animal , how foods diﬀer Dunbar  noted that the use of the extended home range in quality and spatial distribution , and the general during the dry season might be due to a more patchy dis- foraging strategy of the animal. In line with the activity time tribution of green grasses. However, home-range size is also budget for moving, the mean daily travel distances of the dependent on other factors, including group size , en- study group in grazed areas were greater (2.02 km), than the ergy requirements of animals  and intragroup interac- daily travel distance in nongrazed areas. )is indicates that tions . Reuse frequency or overlap of home range was geladas increased their daily range length to meet their higher in grazed areas than nongrazed areas during the dry nutritional requirements as a strategy. As a result, geladas season and wet season. )is indicates more intensive use of are not adapted to reduce energy expenditure in resource- the home range even if that is disturbed because geladas scarce areas but rather to maximize their daily travel cannot extend their home range beyond this as the habitat is distance. cliﬀy and disturbed . In agreement with this result, Dunbar  and Wol- degeorgis  reported that habitat quality due to livestock grazing inﬂuences daily journey length (i.e., animals have to 5. Conclusion cover proportionately longer areas to ﬁnd the food they need as the sources decline). )e present study also showed that Livestock grazing is a major challenge for the conservation geladas move less when food availability is high in non- of geladas in the afro-alpine areas because livestock of the grazed areas; but when food scarcity occurs, geladas roam local people graze and compete with the gelada pop- larger areas in search of food which is in concordance with a ulations. )erefore, understanding the behavioral 10 International Journal of Zoology ﬂexibility of primates in response to livestock grazing is Acknowledgments crucial to develop an eﬀective conservation management )is work was supported by Ethiopian Wildlife Conserva- strategy. Our study found that grazing has a negative eﬀect tion Authority (EWCA) and the Simien Mountains National on the activity time budget and ranging behavior. Partic- Park oﬃce (SMNP), by granting their permission to conduct ularly, geladas who dwell in grazing areas spent more time the study. In addition, the authors greatly acknowledge the for moving and reduced their social time as compared to ﬁnancial support provided by African Wildlife Foundation geladas who inhabit in nongrazed areas. Moreover, the (AWF). )e authors would like to thank Dr. )ore daily travel distance and home range size of geladas in J. Bergman and Dr. Jacinta C. Beehner from the University grazed areas were greater than in non-grazed areas. )us, of Michigan Gelada Research Project (UMGRP), for always grazing aﬀects geladas by costing energy for more time on oﬀering their advice and providing with prompt and helpful moving and traveling longer daily travel distance. Besides feedback on the manuscript and, most importantly, for the energy cost, grazing constrained their social behavior permitting to conduct this study on their already well-ha- which is taken as an important social glue to maintain a bituated geladas and providing some parts of ranging data. larger group size in geladas. On the other hand, the sig- )is work was supported by the African Wildlife Foundation niﬁcant negative correlation on the time budget for moving (AWF). and social time is an indication of behavioral activity time budget tradeoﬀ to cope with the eﬀect of grazing on their energy balancing adaptation. References Increased livestock free grazing in a protected area costs  S. Gippoliti, “'eropithecus gelada distribution and variations the conservation and also reduces the satisfaction of related to taxonomy: history, challenges and implications for livestock herders . 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