PSGB Spring Meeting 1998

Conference Centre, Bristol Zoo Gardens,
Clifton, Bristol, UK.

6th and 7th April 1998

Day 1 (6^th April): Bushmeat Hunting and African Primates

09:30 Registration

09.45 Opening Remarks

Where are we? Chair: J.E. Fa

10:00 Eating our Relatives - Ethics, Ecology and Extinction. Ian Redmond.

10:30 Is Sustainable Hunting At All Possible? John Robinson.

11:00 Coffee Break

Some examples Chair: I. Redmond

11:30 Regional Differences and Hunting Pressure on Chimpanzees in Guinea. Rebecca Ham.

12:00 Market Hunting in Congo. Steve BIake & Liz J. Rogers.

12:30 The Importance of Bushmeat in the Bonobo Distribution Area, Democratic Republic of Congo. Jeff Dupain.

13.00 Society AGM

13:30 Lunch

Providing Solutions Chair: E. Rogers

14:30 Assessing Impact of Hunting: Lessons from Standardized Line-Transect Censusing : from the Neotropics. Carlos Peres.

15:00 The Bushmeat Trade and the Demise of Primates in Bioko Island: What are the Altematives? John E. Fa, Juan Enrique Garcia Yuste, Ramon Castelo & Jaime Perez del Val.

15:30 WSPA's Campaign to Conttol The Bushmeat Trade. Karl Ammann & Jonathan Pearce.

16:00 Tea Break

16:30 What Threat does the Bushmeat Trade Present to Primates and How Can NGO's Help? Evan Bowen-Jones & Stephanie Pendry.

17:00 Panel Discussion

Day 2 (7^th April) : Proffered Papers

09:50 Opening Remarks

10:00 Chimpanzee Cultures. Andrew Whiten

10:30 Reconciliation: Why bother? Julia Casperd

11:00 Coffee Break

11:30 Primates as the main seed disperser of the most species-rich family (Sapotaceae) in central Amazonia. Wilson R. Spironello

12:00 Vertical Segregaton and Interspecific Competition in Mixed-Species Tamarin Troops. Mark J. Prescott & Hannah Buchanan-Smith

12:30 Lunch and PSGB Council Meeting

14:00 Update from the Karisoke Research Centre Liz Williamson

14:30 Social Contact and Distant Communication Vocalizations in Microcebus murinus. Laura V. Harste

15.00 Tea

15.30 Food and feeding behaviour of the pig-tailed macaque in semi-evergreen forest in Bangladesh. M.M. Feeroz

16.00 Interactions between Two Newly Neighbouring Groups of Allen's Swamp Monkeys (Allenopithecus nigroviridis) at Edinburgh Zoo. Anne Gallagher-Thaw

16.30 Meeting ends.

A registration/information desk will be available from 9 am and throughout the day. There will be a book display, information on primate captive care and conservation issues, and a variety of PSGB fund-raising goods for sale. The cost of registration will be £5 for Student PSGB Members, £10 for PSGB Members and Student Non-Members and £20 for Non-Members for the two days of meetings.

Abstracts

Bush-meat Hunting and African Primates: 6TH APRIL 1998.

EATING OUR RELATIVES: ETHICS, ECOLOGY AND EXTINCTION.

Ian Redmond, Wildlife Consultant, P.O. Box 308, Bristol BS9 7LQ, UK.

Bush-meat has become a contentious issue in recent years, but there is more than one bone of contention here. Those who object to the rapidly growing trade in the meat of wild animals do so for widely different reasons. By summarising them in this first paper, I hope to set a framework for the other presentations and the discussion which will end this afternoon's session. Consider your response if, as a fieldworker, the study animals which you had invested time and money in habituating, were killed and eaten. How would you react? As primatologists, we are trained to make objective observations of behaviour and events. If predation by human hunters is the norm in your study site, would you simply record the data in the same way as for a non-human predator? As primates, however, we have evolved to adopt the customs and behaviour patterns of the society in which we grow up. Should you express your distaste to the hunters, or try to dissuade them? As open-minded citizens of the world, we now consider it politically incorrect to criticise other people's cultural practices. But where do you draw the line? In the last century, missionaries and colonial powers more-or-less ended the practice of cannibalism. And some opponents of the bush-meat trade have called for an almost evangelical approach to conservation in order to stamp out the practice of eating apes. Are we right to impose our ethical or cultural values on other, older societies? Would our reaction be different if our late study animals were an endangered species protected by law? What if they were killed for profit rather than survival? The greatest demand for bush-meat now comes from non-traditional urban consumers, and the commercial hunters and traders use non-traditional weapons and transport. The problems surrounding bush-meat are complicated by the growing interest in the sustainable utilisation of wildlife with slogans like 'use it or lose' and 'if wildlife pays, it stays'? Unfortunately, the examples of sustainable use are few and far between when distant commercial markets depend on populations of wild fauna and flora. If the level of hunting is causing a decline in the population, there will be ecological ramifications. Primates are often keystone species in their habitat, and their disappearance can lead to significant changes in the remaining ecosystem. Plants which depend on them for seed dispersal, for example, will decline, as will any animal species which feed or otherwise depend on those species of plant. Thus there are good ecological arguments for limiting hunting for bush-meat - and if the habitat is a sustainable source of other revenues, good economic ones too. Whether for ethical or ecological reasons, however, there is now a consensus among conservation and animal welfare NGOs that the bush-meat trade is out of control. Extinctions will follow if nothing is done to control it. Perhaps today we can agree on how we as primatologists can best respond.

LIMITS TO SUSTAINABLE HUNTING IN TROPICAL FORESTS.

John G. Robinson, Wildlife Conservation Society, New York, USA. WildCons@aol.com

I explore the biological limits to sustainable hunting in tropical forests, drawing upon examples in Asia, Africa, and Latin America. People have hunted wildlife in tropical forests for thousands of years, depending largely on ungulates, primates, and rodents. Standing biomass of these taxa in forests however is low in comparison to biomass in open habitats, rarely exceeding 1000 kg/sq km. Consequently, maximum production for human harvest in tropical forests is correspondingly low, rarely exceeding 150 kg/sq km. Primates in particular, because of their low intrinsic rates of population increase, have low annual productions. Population densities of forest-dwelling people who depend on wildlife harvesting is therefore limited, and densities of indigenous peoples traditionally have been much less than 1 person/sq km. Despite these limits to wildlife production, tropical forest wildlife harvests have increased dramatically in recent years, through (1) increases in the accessibility to tropical forest areas, (2) increases in effective human population density, (3) increased sedentarism and social differentiation, (4) changes in hunting practices, (5) increased commercialisation of wild meat trade, and (6) income increases of urban consumers. Today, much of the subsistence and commercial hunting in tropical forests is no longer sustainable.

REGIONAL DIFFERENCES IN HUNTING PRESSURE ON CHIMPANZEES IN THE REPUBLIC OF GUINEA.

Rebecca Ham, Dept. of Psychology, University of St. Andrews, UK. rham@srv0.bio.ed.ac.uk

A nation-wide chimpanzee survey was conducted Nov. 1995 - June 1997 in the Republic of Guinea in West Africa as part of the Projet de Conservation des Chimpanzes. The goal of the project was to determine the distribution and abundance of chimpanzees and identify threats to their survival in order to formulate an action plan for their protection within the country. Data were collected through questionnaires. reconnaissance surveys and transects. There are four regions in Guinea, (Guinee Maritime, Haute Guinee, the Fouta Djallon and Guinee Forestiere), distinct in climate, vegetation, topography, culture and language. The study therefore looked at differences in abundance of chimpanzees and differences in hunting pressure on chimpanzees between these four regions. The Fouta Djallon, situated in the central highlands of the country, is where chimpanzees were found to be most numerous. Although the Fouta Djallon is only about one quarter the size of the total country, it is thought to be home to over half the population of chimpanzees in Guinea. People of the Fouta Djallon rarely eat chimpanzee meat due to traditional, cultural and religious beliefs. In other regions of Guinea, chimpanzees are less abundant and are sometimes eaten. This is especially true in Guinee Forestiere, the southern-most region of Guinea. There is a huge refugee crisis here, with more than 650,000 refugees from Liberia and Sierra Leone. As many as 13% of the people in refugee camps suffer from malnutrition. The extremely high human population in this region, their search for animal protein and the fact that many remaining forested areas are fragmented and therefore easily accessible, has meant that there are very few places where chimpanzees can exist. It seems that the greatest hope for the future of chimpanzees in Guinea, lies in the Fouta Djallon. Unfortunately, the future protection of chimpanzees even in this region remains bleak. With improved roads and infrastructure within the country, people are coming to the Fouta Djallon to kill chimpanzees and export their meat to other regions of the country where chimpanzee meat is eaten. In addition, although many older hunters in the Fouta Djallon appear to consider chimpanzees sacred, many of the younger generation of hunters do not seem to hold the same beliefs. Suggestions for the future protection of chimpanzees within the country include: (1) increased responsibility of local people for their wildlife and forests, (2) conservation education and public awareness campaigns, (3) encouraging communication between elders and the younger generation in the villages, (4) stricter laws on hunting chimpanzees, and (5) stricter law enforcement. Hunting and eating chimpanzees is not the only factor threatening the long term survival of chimpanzees within the country. Deforestation is taking place at a rapid rate. Young chimpanzees are often taken from the wild for sale as pets. Hunting chimpanzees for their meat however, does seem to be one of the most important factors affecting chimpanzee abundance. In areas where chimpanzees are not hunted, chimpanzees are still found in isolated pockets of forest, often startlingly close to human inhabitation. Here, humans and chimpanzees are found to be living an extraordinarily peaceful and close coexistence.

THE BUSH-MEAT TRADE AND THE DEMISE OF PRIMATES IN BIOKO ISLAND: WHAT ARE THE ALTERNATIVES?

John E. Fa*, Juan E. Garcia Yusteð, Ramon Castelo" & Jaime Perez del Val+, *Jersey Wildlife Preservation Trust, ðCUREF, Bata, Guinea Ecuatorial; "AsociaciÛn Amigos de DoÒana, Apartado de Correos 2182, Sevilla, Spain; +Museo Nacional de Ciencias Naturales, CSIC, c/. JosÈ Gutierrez Abascal 2, 28006 Madrid, Spain. mcnv103@fresno.csi

While there have been attempts to develop indices and models to evaluate sustainability of hunting practical solutions of how to achieve this are lacking. Developing these solutions will require measuring the impact of hunting and also the needs of the consumer population, a measurement complicated by other factors such as accelerating deforestation. Wildlife preservation, while partly related to the management of animal populations, ultimately has more to do with the regulation of supply and demand. Generally, subsistence hunting for consumption at the village level may not pose a severe risk to prey populations where human numbers are low and enough habitat is available. On the other hand, commercialisation of game, at levels now seen in several west and central African countries, can rapidly develop into uncontrolled exploitation by professional hunters (hunters whose primary income is derived from the sale of wild meat) responding to the ever-increasing demands of the fast-growing towns and cities. Bioko island (formerly Macias Nguema Biyogo and previously Fernando Poo), has a unique and important fauna and flora. Bush-meat is a vital source of protein and cash for the people of Bioko. Administratively, Bioko forms part of the insular sector of the Republic of Equatorial Guinea; the country's capital, Malabo, is located here. There have been few studies on the biodiversity of the island until a major effort, initiated by Spanish biologists, started in 1980. Our summarises the available data on the use of wildlife on the island collected in collaboration with the Spanish programme in 1990-1991 and 1996-1997. We present levels of exploitation from carcass counts in the Malabo market for the two time periods and explore whether the present levels of unregulated hunting are likely to be sustainable in the future. We also review the practicalities of controlling wildlife offtake to sustainable levels, and the development of alternative sources of protein for local consumption.

THE IMPORTANCE OF BUSH-MEAT IN THE BONOBO DISTRIBUTION AREA, DEMOCRATIC REPUBLIC OF CONGO.

Jeff Dupain & L. Van Elsacker, Royal Zoological Society of Antwerp, Kon. Astridplein 26, 2018 Antwerpen, Belgium. bonobo@uia.ua.ac.be

Little is known about the distribution, not to mention the density of bonobos (Pan paniscus) in their putative range on the left bank of the river Congo. The most significant population was indicated to live in the Lomako forest block (3000 km2), between the Yekokora and Lomako rivers. This forest was thought to be isolated; permanent dwellings did not exist there. The bonobos were considered to be threatened mainly from hunting for direct consumption, hunting for the pet trade and from snare injuries from traps for other mammals. However, in a 1.5 month survey in 1995 along the Yekokora, which was partly redone in 1998, and a one year stay along the Lomako, has revealed a previously unknown but ever growing human pressure on the species. Because of the deteriorating economic prospects, people are re-migrating into the forest and concentrate on commercial exploitation of the forest resources. Markets are in the larger cities such as Basankusu, Mbandaka and Kinshasa. The lumber companies are the intermediaries between the hunters in the forest and the people in the cities. A study, focusing on the different aspects of the bush-meat trade in the region, is to be started. At Basakusu, carcasses counts are being carried out, and by means of questionnaires, the importance of bush-meat as an income for the hunters and traders, and food for buyers-consumers will be established. Attention will also be paid to traditional medicine, superstition etc. During the 1998 survey, emphasis was placed on the influence of a nearby lumber company. Bush-meat as a well as cartridges are transported by means of company boats. The bush-meat-traders are lumber company families. Thus, due to the concentration of employees, local needs are augmented. Given these facts, lumber companies create preferred market opportunities. Clearly, although more studies in the region are needed to quantify the importance of bush-meat and to analyse the network of the bush-meat trade, action must be promptly taken in the mean time to diminish the threat to the bonobo and other local fauna.

ASSESSING THE IMPACT OF HUNTING: LESSONS FROM STANDARDISED LINE-TRANSECT CENSUSSING IN THE NEOTROPICS.

Carlos A. Peres, School of Environmental Sciences, University of East Anglia, Norwich, UK. C.Peres@uea.ac.uk

Subsistence hunting of game vertebrates, including primates, affects vast expanses of tropical wilderness that have otherwise been left structurally unaltered. Distinguishing hunted from entirely pristine tropical forests thus presents a difficult problem because this is an inconspicuous form of resource extraction leaving few visible signs of its occurrence. This study examines the effects of selective hunting on the structure of primate communities at 56 Amazonian forest sites. Nearly half of these sites have been surveyed using a standardised series of line-transect censuses conducted over a 10-year period. Hunting had a profound impact on the total primate biomass and relative abundance of different-sized species at these forest sites, but did not necessarily affect their total primate density. The study further examines the effects of forest type and habitat productivity on the relationship between hunting pressure and primate biomass. This cross-site comparison is one of the first large-scale attempts to document the staggering impact of subsistence hunting on primate community structure, and highlights the importance of considering habitat quality in game management programs in the tropics.

COUNTERING THE IMPACTS OF THE BUSH-MEAT TRADE IN CAMEROON.

Chris Mitchell, CWAF Project Manager, PO Box 11, Mold CH7 4ZG, UK. C_Mitchell7@compuserve.com

Others papers have discussed the bush-meat trade and have highlighted some of the consequences. This paper proposes that urgent action is required to avoid the extinction of apes wherever the bush-meat trade poses a threat. Outlined are strategies for lessening the conservation and welfare problems associated with the trade and information about the activities of the Cameroon Wildlife Aid Fund (CWAF) who are working on conservation's front line. The solutions proposed fall into four main categories:- a) TIMBER COMPANIES: To apply commercial pressure on these companies in the region who presently facilitate the movement of bush-meat from their concessions to population centres and actively promote the hunting of bush-meat within their concessions. CWAF is too small to lobby these companies but does believe this to be a strategy worth pursuing. To that end we are active members of the Ape Alliance whose collective membership runs to millions and thus wields considerable influence.; b) LAW ENFORCEMENT: Enforcement of Cameroon's existing wildlife law is the responsibility of game guards who are under strength and ineffective and the aim will be to improve the situation by funds permitting to provide equipment; upgrading the image and status of the game guards and increasing their efficacy by attacking the weak links e.g. transportation; campaigning for a change in the law that currently allows game guards to confiscate illegal bush-meat then auction it to the highest bidder and running motivational workshops for game guards; c) PROVIDING ALTERNATIVES: It is not just the animals that are the victims of this commercial slaughter in the forest but also local people like the Baka pygmies. They are exploited by greedy middle-men who provide them with a pittance in exchange for bush-meat and when these traders and timber camps move on wildlife resources can be seriously depleted. CWAF would like to study ways of providing alternative sources of income for those engaged in hunting and also to develop utilisation of novel protein sources; d) EDUCATION The conservation policy requires the support of the politicians and whole populace. A potent and energetic approach to education with emphasis on the young is needed - the aim is as simple as it is daunting - to educate a generation. Education will be the core activity from an 500 ha base near Yaounde. As many people as possible will be reached by using the national media, school programs, visitor education and out reach missions to real trouble spots. Additional to the above is the need to tackle the welfare issue created by orphaned apes by providing them with a sanctuary where their dignity can be respected and they can be looked after for the term of their natural lives. This exercise would be futile without tacking the root causes of the never ending stream of tragic orphans that arrive in Yaounde. For the sake of these orphans and Cameroon's wildlife very high priority must be given to tackling the illegal bush-meat trade.

WSPA'S CAMPAIGN TO CONTROL THE BUSH-MEAT TRADE.

Karl Ammann* & Jonathan Pearceð, *Advisory Director, WSPA, P.O. Box 35, Nanyuki, Kenya; ðCampaign Manager, WSPA, 2 Langley Lane, London SW8 1TJ, UK. jpearce@wspa.org.uk

WSPA's campaign began after a field investigation in Zaire, Congo and Cameroun by Karl Amman and Garry Richardson. This confirmed Ammann's long held theory that the bush meat trade was widespread, commercialised and accelerating due to the growth of the timber industry. Since this problem was not widely understood, either by the conservation community or by western consumers of timber, WSPA initially embarked on a publicity campaign, which provoke a great deal of concern from many sectors as well as scepticism and rebuttal from other audiences. The campaign highlighted the plight of apes, since, as well as being species particularly at risk, they are also species for which most people have a strong concern. Lobbying was conducted at EU level and a government conference was organised in Cameroon, involving members of the timber industry. Humanitarian aid was provided by WSPA to several sanctuaries working to rescue orphaned apes. The campaign showed how most of these animals were brought into captivity because of the bush meat hunting. The response to the campaign from the timber industry and from African governments has been very poor, but the conservation community has no shown a much stronger interest in addressing the bush meat trade. In order to broaden the concession of opinions WSPA helped to establish the Ape Alliance, which has become active on the issue. The timber industry has been addressed most positively by introducing the concept of hunting control within the certification movement, through bodies such as the FSC. Unfortunately, as yet no concessions in Central Africa have achieved an appropriate standard for certification. Continued work is needed to investigate and publicised the threats to wildlife from hunting in this region. Only when the scale of the problem is widely accepted will effective action be possible on the ground.

WHAT THREAT DOES THE BUSH-MEAT TRADE PRESENTS TO PRIMATES AND HOW CAN NGO'S HELP?

Evan Bowen-Jones & Stephanie Pendry, Fauna and Flora International, Great Eastern House, Cambridge, UK. ebjno2@compuserve.com

Over recent years evidence from field workers including many primatologists has pointed to the fact that hunting of wild species including primates has reached unsustainable levels. This is due to increases in technology, access and human populations in formerly remote areas. Data from west and central Africa allows analysis of the scale of the problem that threatens to cause the extinction of a number of species, including some primates. The bush-meat trade represents a more immediate threat to biodiversity in significant areas of the tropical forest than habitat destruction. Although the data collected give very conservative estimates of the number of animals killed they begin to provide comparative information on the species and groups affected. As well as primates, less well-known taxa are also at risk. Therefore, if we are to attempt to implement pragmatic species conservation, holistic solutions that maintain complete ecosystems are required. Non- Governmental Organisations working on conservation, community, and development issues are in a position to act to achieve these goals. However, so far little effective action has been taken. Research on alternative protein sources, sustainable harvest, and quota systems has been carried out but it is generally acknowledged that good protected area management will always be a crucial conservation tool. Another vital element will be community conservation and education work, and it is clear that the scale and complexity of the problem dictates that NGO's must co-operate with one another. If the impact of the bush-meat trade is to be limited, a multidisciplinary approach to influence both people and governments is required.

PROFFERED PAPERS: 7TH APRIL 1998.

CHIMPANZEE CULTURES.

Andrew Whiten, Scottish Primate Research Group, School of Psychology, University of St Andrews, St Andrews, Fife KY16 9JU, Scotland. a.whiten@st-andrews.ac.uk

As long term field studies of chimpanzees have become established in different parts of Africa, more and more signs of cultural variation have accumulated. I present here a new collation of the numerous putative cultural variants that have been described, based on an ongoing consultation exercise spanning the major study sites. The catalogue extends to over 30 behaviour patterns. Evidence that several of these variants are indeed culturally transmitted includes: 1) studies explicitly excluding ecological explanations; 2) variations in the details of otherwise similar acts; and 3) apparent social customs. This evidence is complemented by our experiments on social learning in captive chimpanzees, which have provided the first strong experimental evidence for an animal's imitation of the sequential structure of actions. That this matching emerged only after repeated observations of a model and repeated attempts suggests that chimpanzees have tendencies to converge on cultural similarities. The phenomenon of chimpanzee cultural variation suggests that it is not only species and subspecies that deserve conservation: we are in danger of losing a cultural diversity that is reminiscent of human tribal diversity in similar parts of the world.

RECONCILIATION: WHY BOTHER?

Julia Casperd, Department of Psychology, University of Liverpool, P.O. Box 147, Liverpool L69 3BX, UK. J.M.Casperd@liverpool.ac.uk

The process of reconciliation is much talked about, not only at scientific conferences on animal behaviour, but in human politics and marriage guidance. Why is it so important to make amends and what are the implications if one doesn't? This paper explores these issues by evaluating the numerous hypotheses that have been put forward in the literature to explain the evolution and function of reconciliation. It does this using theoretical models of non-human primate post-conflict behaviour (N=21 species), as well as analyses of post-conflict (PC-MC pairs sampled: N=1220) and social network data from a captive group of chimpanzees (N=19 adults and subadults). The results of this work are discussed in relation to the definition and measurement of reconciliation, the evolution of reconciliation and primate social systems, and the future of post-conflict research.

PRIMATES AS THE MAIN SEED DISPERSER OF THE MOST SPECIE-RICH FAMILY (SAPOTACEAE) IN CENTRAL AMAZONIA.

Wilson R. Spironello, Wildlife Research Group, Department of Anatomy, University of Cambridge, Cambridge CB2 3DY, UK. Biological Dynamics of Forest Fragments Project, INPA/SI.

Sapotaceae is the richest family in this study site (north of Manaus) in central Amazonia. The family comprises about 11% of all trees >10 cm dbh (110 species). Previous studies indicated that Sapotaceae fruit was one of the most important food resources for animals in other Amazonian sites (which is supported by data recorded in the study area on primate species). Some studies (based on fruit morphology) have suggested that Sapotaceae fruits are dispersed by mammals, mainly primates, but no studies have recorded frugivory on this family to date. Thus, the main aims in this study were: 1) to record all frugivore species that used these fruits, (2) to estimate the amount of seed dispersed by different species based on fruit-trap data, and (3) to test whether primates were the main arboreal seed disperser agents, as previously hypothesised. The study data contained 34 individual trees (9 species), with fruits ranging from 15 mm to 75 mm in length. Fruit traps were checked at dawn and dusk, and as well as other times of day, and all fruits were assigned separately to frugivorous species (based on survey and/or tooth marks). Data analyses were based on 937 frugivory records, 442 of which were pulp-consumer species (primates, 53.4%). Insects, rodents, parrots, and black-saki monkeys were the main seed predators of the target species, taking 57.4% of all harvested fruits. On the other hand, the percentage of seed dispersal (seeds taking away from the fruiting tree and/or swallowed) accounted for 18.2%. Primates were the main arboreal seed dispersers (65%) at the community level, although kinkajous (Potos flavus) were an important nocturnal seed disperser for small to medium-sized seeds. Although the target family is the richest tree species in the area, most species are rare and dioecious, and to some extent, dependent on mammal seed dispersers. Hunting effects have been increasing sharply in Amazonian forests due to human activities, especially for medium- to large-sized animals, and forest fragmentation is increasing, but the regeneration processes of most Sapotaceae species may depend on seed-dispersal agents and large forest areas, hence forest composition is likely to be more seriously affected by forest disturbance in the future.

VERTICAL SEGREGATION AND INTERSPECIFIC COMPETITION IN MIXED-SPECIES TAMARIN TROOPS.

Mark J. Prescott & Hannah M. Buchanan-Smith, S.P.R.G., Department of Psychology, University of Stirling, Stirling, FK9 4LA, Scotland. H.M.Buchanan-Smith@stirling.ac.uk

Mixed-species troops are found wherever Saguinus fuscicollis, the saddle-backed tamarin, lives sympatrically with either S. mystax (moustached tamarin), S. labiatus (red-bellied tamarin) or S. imperator (emperor tamarin). According to the competitive exclusion principle, whenever two closely related species with strongly similar ecological requirements occur sympatrically, they enter into interspecific competition which either drives one of the two species to local extinction or leads to character displacement. At first glance then, mixed-species tamarin associations would appear to contradict this principle. However, associating species exhibit divergence in several dimensions of their ecological niche which allows their coexistence. For example, they use different insect foraging strategies, locomotor styles, substrates and heights in the forest. Vertical segregation was investigated in wild troops of S. fuscicollis in association with either S. labiatus or S. imperator. Overall, S. fuscicollis were found at a significantly lower height in the forest than their congeners. Comparing the associations with each other and with previously published data for S. fuscicollis / S. mystax associations, it is found that the amount of association is positively correlated with increasing vertical segregation, it being greatest in S. fuscicollis / S. mystax troops and least in S. fuscicollis / S. imperator troops. This suggests vertical segregation plays an important role in mixed-species troop formation, possibly by reducing interspecific competition. To examine this, experiments in captivity were conducted in which feeding boxes were presented at two different heights. In single-species troops, S. fuscicollis fed from the lower box more quickly than S. labiatus, and S. labiatus were quicker to feed from the higher box than the lower box. If the quantity of food placed in the lower box was greater than that in the higher box this preference was changed. Preferences were also affected by the presence of a congener. S. labiatus fed more quickly from the lower box in the presence of S. fuscicollis. S. fuscicollis were disadvantaged in mixed-species troops in that they were excluded from the food by S. labiatus. These results are discussed in relation to competition in the wild.

UPDATE FROM THE KARISOKE RESEARCH CENTRE.

Liz Williamson, Director, Karisoke Research Centre, B.P. 1321 Kigali, Rwanda. DFGF-RWANDA@MAF.Org

The 30th anniversary of the Karisoke Research Centre came at a time when personnel were unable to enter the Parc National des Volcans, and the Dian Fossey Gorilla Fund's expatriate staff had been based in the capital for seven months. Here we present what is known about the gorillas and the situation in the park prior to and since June 1997. At the beginning of 1997, monitoring the gorillas continued seven days a week. In June, research and monitoring, anti-poaching activities and tourism were suspended due to rebel activity in and around the PNV. The local population subsequently took advantage of the lack of protection for the park's flora and fauna, and there was an increase in the intensity of illegal activities. While patrols were still active, four gorillas casualties of antelope snares, and 673 illegal snares were removed by Karisoke anti-poaching teams. As we are unable to monitor and intervene, accidental snaring maybe the biggest threat to the mountain gorillas in the current situation.

FOOD AND FEEDING BEHAVIOUR OF THE PIG-TAILED MACAQUE (MACACA NEMESTRINA LEONINA) IN SEMI-EVERGREEN FOREST IN BANGLADESH.

M. M. Feeroz, Wildlife Research Group, Department of Anatomy, University of Cambridge, Cambridge CB2 3DY, UK.

A study was conducted on the pig-tailed macaque Macaca nemestrina leonina between May 1996 and September 1997 in the semi-evergreen forest of West Bhanugach reserve forest in Bangladesh. This is the first long-term study of this sub-species of pig-tailed macaque in its north-western-most geographical distribution. The main aim of this study is to find out how this species fulfil their feeding needs from a more seasonal semi-evergreen forest. This sub-species is completely arboreal and frugivorous. The group spent 21.7% of their daily active time on feeding and 39.6% time on foraging. A total of 93 species was used for different food items, of which, the group spent 79.3% of their total feeding and foraging time on 18 species. Number of species used each month varied from 13 to 28 species. The diet was composed of fig (48.6%), fruit (37.9%), foliage (4.7%), animal matter (2.8%), flowers (2.6%), seeds (1.9%) and unidentified (1.5%). Height of the food sources varied from 3.5 to 31m. The feeding and foraging height of the individuals varied from 2.5 to 28m and 1 to 22m respectively. Juvenile used larger vertical areas for feeding (5.5 to 28m) and foraging (4 to 21m), while the adult female used the smallest vertical areas for feeding (4.5 to 21m) and foraging (4 to 14m). There is a significant relationship between their distance from the tree trunk and the thickness of the substrates they used during feeding and foraging. Inter-specific conflict for food resources was observed between the pig-tailed and hooloch gibbon, rhesus macaque and capped langur.

Social contact and distant communication vocalisations in microcebus murinus.

Laura V. Harste, Evolutionary Psychology Group, School of Biological Sciences, University of Liverpool, Liverpool, UK.

This study examined the use of vocalisations in maintaining social ties in a captive colony of 17 Microcebus murinus at the Duke University Primate Center. All calls were recorded ad libitum in conjunction with behavioural observations. Frequency of vocalisations throughout the study was examined to understand the uses of different call types, importance of each call and to determine whether group formation affects the frequency of call emission. The eleven individual calls which were heard throughout the study were divided into three main categories: contact and contact-seeking, distant communication, and contact-rejection. The frequency of emitted calls displays the importance of vocal communication in the formation and maintenance of social ties. The data collected during this study suggest a level of sociality in this species. The main question to answer is: if these animals are solitary, why would they need such a range of social contact calls? The existence of these calls suggests that mouse lemurs are using vocal communication to maintain social contact with other animals and to group together at certain times. The fact that these calls were not as frequently used when the animals had formed a strong bond and spent more time in physical contact, suggests that there is a level of social bonding between individuals. Presumably these social contact calls would still be important in the wild, where the animals would be more dispersed throughout the year. A solitary, or semi-solitary, existence therefore appears to be unlikely in a species which is using vocal communication to attract known individuals and to maintain a stable relationship with them.

Interactions between two newly neighbouring groups of ALLEN'S SWAMP MONKEYS (Allenopithecus nigroviridus) at Edinburgh Zoo.

Anne Gallagher-Thaw & Erika Morgan, Education Dept., Edinburgh Zoo, Murrayfield Edinburgh, UK;, Department of Zoology, Glasgow University, Glasgow, UK.

Enrichment of primates in captivity generally focuses on non-social aspects of the environment; such as enclosure complexity and food-related enrichment. Although efforts are made to maintain social animals in groups, other forms of social-related enrichment; such as the provision of neighbouring conspecifics, is rarely focused upon. Nevertheless, a major part of primate behavioural repertoire involves social relationships and reactions to social stimuli. It is important to encourage as full a range of natural behaviours and stimulus responses as possible, not only to enrich the animals' captive lives, but also to maintain a viable group that will (if the situation should arise) be suitable for returning to the wild. The provision of neighbouring conspecifics would expose captive animals to a range of natural stimuli similar to those experienced by their counterparts in the wild, would be experienced by all members of both groups and should improve social stimulation in captivity. The aim of this study was to compare the behaviour of a group of Allen's Swamp monkeys (Allenopithecus nigroviridis) before, during and after the introduction of unfamiliar conspecifics to their neighbouring enclosure. Data on activity budgets of individuals and inter- or intra-group interactions were recorded and a number of new species-typical behaviours were observed. These included sex, male-male aggression, scent-marking and vocalisations. Increases in time spent actively watching or interacting with other individuals, both within and between the groups, were also recorded. These results support the suggestion that the social environment of an animal is of great importance when considering types of enrichment for a species. A more complex and variable social environment increases the complexity of experiences to which captive animals can be exposed and encourages species to exhibit a greater range of species-typical behaviours.