This section contains studies into the abundance of Macaca ochreata brunnescens (14.2), the behaviour and ecology of the species (14.3) and the impact of the macaques through crop raiding on the local communities (14.4).

Introduction

The aim of this project were to estimate the abundance of the Buton Macaque, Macaca ochreata brunnescens in a range of forest types and to compare the estimated densities with levels of disturbance to the forest and distribution of fruiting trees.

Macaca ochreata brunnescens foraging ; Photo Eddy Dunne

Two sites were chosen in which to carry out this study – one near the Forest Research Centre of Labundo Bundo and the second near the village of Toruku. Abundance was measured using line transects which followed trails through the forest. These were positioned in no particular pattern but walked where existing trails were present. Nine transect were surveyed at Labundo Bundo and eight at Toruku ranging from 1650metres to 2250 metres. GPS positions were recorded for the start and finish of each of the transect lines and compass direction noted every 150m along the trail. Each transect was surveyed 3 times. On the first survey of each transect the following parameters were recorded at each 150m along the transect; compass direction of trail, estimated canopy height from triangulation, canopy cover within a 2m radius circle directly above the transect and any changes in the forest or significant land features were noted. 14 different taxa of fruiting tree were identified as potential food sources for the macaques which from literature surveys of closely related species are likely to be predominantly frugivorous.

The transects were walked slowly with 2or 3 observers watching and listening for macaques. The time each macaque was first noted was recorded as well as its perpendicular distance from the transect. The number of macaque troupes seen along the transect was noted.

The forest at Toruku appeared to be closer to primary than at Labundo Bundo. The mean number of fruiting trees per transect at Toruku was 52 whilst at Labundo Bundo the average was only half this value with 25 fruiting trees per transect. More macaques were recorded from the Toruku forest transects and macaques were recorded from a greater proportion of the Toruku transect surveys (67%) than for the Labundo Bundo transects (41%).

Many of the transects at both of the sites contained patches of disturbed forest and it was impossible in these cases, to classify the transects into single habitat categories. The data analysis will take these variations into account . Crop raiding is a significant food source for macaques so abundance will be examined against distance to the nearest farm.

Report

A dissertation entitled The Abundance of the Buton Macaque, Macaca ochreata in Relation to Forest Disturbance and Proximity of Farmland was prepared in March 2001 by Sarah Cadbury from the University of Birmingham.  A copy of the dissertation is available at the Labundo field centre and the UK offices.

The aim of the study was to obtain data on the time budgets in various behaviours/activities of a study group of macaques, whilst also making notes on other unusual behaviour and feeding habits etc.

Scan sampling was employed which involves, tracking (or attempting to) the study group from 5.30am until 6.00pm (sunrise to sunset), and scanning the group at regular intervals whilst they are in sight. The group was scanned every 4mins and the rank of each individual and the behaviour it was performing was recorded. In addition the food types and other unusual behaviours were also recorded. The study group comprised;

1 X Boss Adult Male (BossAM)

1 X Adult Male (AM)

4 X Adult Females (AF) - one grey female.

2 X Sub-adult Female (SF)

2 X Sub-adult Male (SM)

4 X Juvenile Male (JM) – only 3 at end of study.

2 X Infant Male (IM) – no newborn infants, both are predominantly independent and eat solid foods, however they do travel attached to their respective mothers and suckle on occasions.

The definitions of social rank were roughly defined prior to leaving for Indonesia and modified in the field after the first week’s preliminary observations, when no data was taken. Rough estimates of the weights of each group were also made; BossAM~70 kilos, AM/AF~40-50 kilos, SM/SF~30-40 kilos, JM/JF~15-25 kilos, and IM/IF~5-15 kilos.

1. Boss AM: The largest of any of the individuals in the troupes by far. Looks very much like a small gorilla due to their thick black fur and gorilla like stance and walk, and were never witnessed at play in this study. They are very well muscled and are impressive looking. Also the most easily distinguishable and noticeable of the entire troupe. It also makes a characteristic loud clucking noise when it wants to signal for the troupe to move, stop, or is angry, and this vocalisation is only made by the Boss male of each troupe.
2. SM: Similar behaviour and postures as the Boss AM, however, are far smaller and do not have the full pelage of the Boss (i.e. Bluish-grey patches at the top of the rear are not fully developed). They are also less square shouldered and well muscled, and are more frequently involved in play activities.
3. JM: Smaller than the sub-adults and far more round-shouldered. They are very frequently involved in play activities, particularly with the infants (Chases and fights etc.). They (also in infants), unlike the adults and sub-adults, have a loping gait rather than the more purposeful striding of their elders. Juveniles can also be distinguished from infants in that they are entirely independent of their mothers.
4. IM: These are very similar to the juveniles, with only a slight difference in size for some, but in general they are a bit smaller. They are also not entirely independent of their respective mothers and can be seen attached to and suckling from them (although the infant males in this troupe seemed quite old and were even eating solid foods, they were classed as infants due to their small size and in particular their slight dependence on their mothers). The infants also spent a lot of time in play activities and would even try to play with the sub-adults and adult females.

Females are distinguishable from males in three ways; Firstly, and most obviously are the genitals i.e. the presence or absence of a penis, secondly in females the perineal skin on the females rear is bald and a red raw colour (more pink in younger females) which is absent in males, thirdly the females nipples are red and are also swollen in adult females.

5. AF: These are the largest of the females although some sub-adults are as big. These have large often swollen perineal patches on the rear, which are a very bright red colour and also have red swollen nipples. They are also similar to the adult males in that they are slightly better built and square-shouldered than their younger counterparts. They rarely play except with their own offspring and are often involved in social grooming.
6. SF: These are the same size or often smaller than the adults with a more round-shouldered appearance. The major distinguishing features of these are that their perineal skin is a lighter; more pink colour compared to that of the females and often covers a smaller area and the nipples, which are neither red or swollen. They are also seen playing more frequently than the adults.
7. JF and IF: Although none of these were present in the study group they were observed on several occasions in the two other groups which invaded the study groups territory quite regularly, and definitions were developed from these. Both of these categories can be described in exactly the same way as males of the same rank i.e. size, independency etc. Also the perineal patch is smaller and lighter in the younger individuals.

Data were recorded in the following behavioural categories which were defined as follows;

1. Self-grooming: This is when the individual is running its fingers through its fur, picking at its fur and also scratching itself, it is almost always carried out when seated and is usually carried out very intently and carefully (when prolonged bout) with look of concentration.
2. Social grooming: As in self-grooming except applied to another individual.
3. Solitary play: This involves an individual playing whilst alone and includes running and jumping around and acrobatics i.e. hanging upside-down from branches and jumping from branches into bushes etc.
4. Social play: Play involving two or more individuals and including chasing and fighting. Distinguished from agonistic by facial expressions and lack of agonistic or submissive vocalisations.
5. Agonistic: Any aggressive display or interaction with another individual (including the observers). These include displays such as branch shaking, posture 1 which is ears back and eyebrows raised and posture 2 which is the same except with the teeth also bared, these may also be accompanied by the animal squatting with the front half of its body low to the ground, face up, with its rear in the air (can also be accompanied by alarm barks (quite urgent/more serious) or alarm grunts (less alarmed/less urgent or serious)). It can also involve actively chasing an individual usually accompanied by grunts/barks a snarling type of noise or even actual fighting (contact) involving biting, scratching, pawing and slapping.
6. Submissive: This behaviour includes running from an aggressive individual and/or cowering (often curled up and low to the ground) in response to an aggressive interaction and is accompanied by squealing and whimpering vocalisations.
7. Watchful: Whereby an individual is staring intently in a particular direction i.e. at another group, individual, or observer whilst standing or sitting.
8. Sexual: Includes masturbation and mountings, which can in younger individuals involve same sex pairings, and may or may not involve actual penetration.
9. Foraging: This includes searching for, preparing (i.e. cleaning food items) and handling food items (digging for and catching food items). The food type foraged for was also recorded; fruit, seed/nut, leaves, roots, bark, pith, fungus/mushrooms, vines, soil, insects and crops (corn, tuber/ubi and cassava, cocoa etc.), and the name of the food identified if possible. Crop raiding was also included as foraging.
10. Feeding: Active consumption of food items, chewing/feeding on food items and the placing of food items in the mouth. Attempts were also made to include feeding on food stored in cheek/neck pouches but this was difficult to spot in the field. As in foraging the food type and name of the food was also recorded if possible.
11. Drinking: Consumption of water either via crouching over a stream and sucking up water or by collecting liquid on the hands (i.e. from leaves, holes in trees and from streams) and licking it off.
12. Locomotion: Involves any movement including walking, running and climbing, where none of the other behaviours are apparent.
13. Resting: When an individual is not moving and it is not performing any of the previous behaviours it is considered to be at rest. This can include standing, sitting, lying and huddling in a group (two or more together), may also include sleep if the individuals eyes are closed.

Also recorded for every individual, alongside its rank and behaviour is whether it is terrestrial or arboreal at the time. Fallen down trees and logs were considered terrestrial.

In addition the location and movements of the group were recorded during the course of the day along with weather changes and the vegetation type at each site.

From this data the time spent by the various social categories of macaques in the various behaviour categories can be assessed. These observations can also be compared to that of other species of macaques to determine whether they follow the same behaviour patterns and ecology. In total, the study included 30 days of field observations (with one week preliminary) with between 2-4hrs-observation time per day. The data will also be used to analyse feeding behaviour and preferred food items.

Reports 

A dissertation entitled Observations on the Behaviour of the Buton Macaque was prepared in March 2001 by Graeme Cooper from the University of Aberdeen.  A copy of the dissertation which was awarded a First is available at the Labundo field centre and the UK offices.

The Buton Macaque which is a protected species, is not perceived by the Department of Agriculture in Buton to be a significant pest to farms. However, initial observations in 1999 had suggested that this may not be the case in farms adjacent to forest areas. This project was designed therefore to assess the level of damage, preferred crops targetted by the macaques and methods by which this raiding impact could be reduced.

Studies were carried out in six villages using semi-structured interviews delivered through an interpreter. Questions covered information about the farm, level of crop raiding experienced and methods used to deter the macaques. Direct observations of crop raiding to record time spent foraging, time of day, number of individual animals feeding and approximate quantity of crop taken were also made. Interviews were also conducted with the Department of Agriculture, Department of Plantations, and the Department of Forestry in the Buton Regency as well as local wildlife rangers in the study areas. Since some of the local people kept macaques as pets, and the collection of wild macaques for this trade could have a significant impact on macaque numbers, this aspect was also investigated by semi-structured interviews with pet owners in the villages.

The interviews with the farmers showed that they considered the macaques to be a significant pest which is at variance with the official view of the Department of Agriculture. The farmers experienced crop raiding attacks ranging from fairly serious to very serious depending on the crops grown and the proximity of the farm to forest. Only the rice growing farms appeared to be exempt from these raids. Methods of deterring them ranged from shouting and throwing stones to the use of dogs, poison and trapping with varying levels of success. Shouting and throwing stones seemed to be the most effective method although this requires a permanent guard to be kept in the fields. A more ingenious method of deterrence, reported in several villages, is the practice of catching a large individual, painting it red and releasing it to run back to the troupe. This terrifies the rest of the group and keeps them away for several months. The capture of macaques for the pet trade did not appear to be a problem since the animals were not perceived as having a commercial value and were kept only if a small one was caught. There was a very low level of awareness of the status of the Buton Macaque as a protected species.

A dissertation entitled The Impact of Macaca ochreata brunnescens on Farms in Buton Island was produced in May 2001 by Nancy Priston from the University of Cambridge.  A copy of this dissertation which was awarded a First is available at Labundo and in the UK offices.