Distribution and conservation status of primates in Bioko island,Equatorial Guinea

Ten species of non-human primates are indigenous to Bioko; half of these are endangered and between five and eight are endemic subspecies. Recent data on their status and distribution have been lacking. In 1986, a ten-week survey of the island was carried out to determine the distribution and status of the primates and the natural vegetation, and to evaluate the effects of man on them. This paper presents the results of that survey, gives an update of conservation achievements since 1986, and highlights current concerns. Between 1974 and 1986 it is probable that numbers of all Bioko primates rose as a result of an increase in habitat and of reduced hunting. At the time of the survey there was considerably more natural, undisturbed, vegetation remaining in Bioko tran expected. Much of this vegetation occurs within two large blocks that are of outstanding importance to the conservation of species in tropical Africa, particularly of plants and primates.     

Seminomadic Ranging in a Population of Black Colobus (Colobus satanas) in Gabon and its Ecological Correlates

We observed ranging patterns in a black colobus population in the Forêt des Abeilles, Central Gabon. We compared the results with those for two other populations (Lopé Reserve in Central Gabon, Douala-Edéa in coastal Cameroun) in order to estimate the extent of specific variability in population structure and ranging behavior and to identify ecological factors influencing interpopulation differences. The mean number of monkeys in a group is 17, and all groups had a multimale structure. Home ranges were large, and the fact that they continued to increase with increasing number of observations indicated that the monkeys did not frequently resample their habitat. Ranging patterns varied according to the staple food consumed: distances travelled daily increased with increasing seed intake and decreased with increasing leaf intake. The ranging patterns of groups of Colobus satanas are seminomadic. Up to 6 or 7 groups shared the same space, and two group ranges could overlap by as much as 65–75%. Comparisons with the two populations previously studied showed that group size and group structure are broadly similar. At all three sites, black colobus were mainly seed eaters and ate large amounts of leaves in the season of fruit shortage. In the Forêt des Abeilles, however, group home ranges were much larger than at other sites, and this population had the lowest density. This is correlated with vegetation composition and with harshness of the main dry season. This colobus population appears limited by both recurring food shortage in the dry season and episodic periods of seed shortage resulting from irregular fruiting of the dominant family Caesalpiniaceae. Their seminomadic ranging would constitute the least costly strategy to cope with the low carrying capacity of their habitat.     

Habitat preference of the Preuss's guenon<Emphasis Type="Italic">(Cercopithecus preussi), on Bioko island,Equatorial Guinea</Emphasis>

The Press's guenon (Cercopithecus preussi) is considered to be one of the most threatened African primates. There is little information on the ecology and status of this primate on Bioko island, where it is found in the form of an endemic subspecies. The Press's, guenon shows preference for theSchefflera forest and the mountain habitat on Bioko island. As on the mainland they also have semitterrestrial habits and are found usually at the understorey of the forest. Competitive exclusion between this guenon and other guenon species could be an explanation of these ecological preferences. Habitat use and vertical stratification of the activity in the forest canopy seem to reduce competition with other sympatric primate species that inhabit on the island. Habitat destruction, and isolation in a reduced habitat, show to be the major threats for the survival of this primate on Bioko island.     

The Spanish co-operation programme in Equatorial Guinea: a ten-year review of research and nature conservation in Bioko

The Research and Nature Conservation Programme in Equatorial Guinea was launched in 1985, financed by the Spanish Technical Co-operation Agency. The Programme's main objectives were to: (i) increase scientific research; (ii) set up a Museum of Natural History for the country; (iii) update environmental legislation; (iv) create a network of protected natural areas; (v) promote Equatorial Guinea's participation in international forums on the environment; (vi) train local personnel and (vii) implement environmental education programmes. Actions undertaken and results obtained over a ten-year period are reviewed herein. The Programme has been important in raising the level of scientific awareness of the country's resources but more importantly, it has catalysed the inception of the country's existing legal framework for environmental protection (Ley 8/1988). Within this law, regulations with respect to wildlife, protected areas and hunting were promulgated. These include the legal basis to create other reserve areas and non-profit organizations related to wildlife protection. The Programme has been able to employ the law to stop exploitation and road-building along the south of Bioko.     

Potential vectors of loiasis and other tabanids on the island of Bioko,Equatorial Guinea

The biting flies Chrysops dimidiatus Wulp and C.silaceus Austen (Diptera: Tabanidae), vectors of Loa loa (Cobbold) (Nematoda: Onchocercidae) on the African mainland, were found to be widespread on the island of Bioko (Equatorial Guinea) during 1996-2001. These tabanids were particularly prevalent in the southern part of Bioko, indicating potential transmission of loiasis on the island. The only other tabanids previously recorded on Bioko, Tabanus argenteus Surcouf (from 1915) and Haematopota near heptagramma Speiser (from 1933), were also collected. The possibility of loiasis being endemic on Bioko contra-indicates ivermectin treatment of onchocerciasis cases, due to risks of adverse side-effects.     

Better to Live with Allogenerics Than to Live Alone? The Case of Single Male Cercopithecus pogonias in Troops of Colobus satanas

We report the integration of single male crowned guenons (Cercopithecus pogonias) into troops of black colobus (Colobus satanas). We observed one male Cercopithecus pogonias in three troops of Colobus satanas on 30% of observation days (n = 231). Activities of single males guenons did not differ significantly from those of the colobus with which they associated. Moreover, both species performed simultaneously the same activities more often than expected by chance. Interspecific grooming occurred on several occasions. Furthermore, single male guenons spent as much in time social activities when part of a colobus troop, as they typically do when part of a conspecific group. Unlike solitary male crowned guenons, which are silent, a male that is integrated into a troop of colobus is vocal and emits social alarm calls to which colobus monkeys respond. During the single file movements of colobus troops, single male crowned guenons were integrated in the core of the troop and used the same branches at the same height with the colobus. Thus, the life of a single male crowned guenon with black colobus was social. We suggest that the main benefits that he gained is the possibility to live in a social context. Social interactions could be the key element to explain why single males Cercopithecus pogonias join troops of monkeys so different from their natal groups.     

Copepoda Poecilostomatoida associated with Bivalvia from New Guinea

Four species of Copepoda Poecilostomatoida are recorded from the mantle cavity of bivalve molluscs collected in West New Guinea (Irian Barat, Indonesia). Two of these are new to science: Pseudanthessius dimorphus and Lichomolgus hoi n. spp.     

Modeling the Impact of Ebola and Bushmeat Hunting on Western Lowland Gorillas

The 2003 outbreak of Ebola in the Republic of Congo killed 114 people and up to 800 western lowland gorillas. This outbreak and all outbreaks between 2001–2003 began with human handling of infected animal carcasses. Ebola has since spread, putting the entire gorilla population at risk. An epidemiological model is presented to describe the combined effects of Ebola and hunting on persistence of gorillas. The number of infected gorillas also provides a means of assessing the risk of transmission to humans. Under current harvest practices and the estimated annual outbreak rate, the gorilla population is predicted to undergo a 97% decline within 100 years. Controlling bushmeat hunting may not be enough to prevent extinction if frequent outbreaks occur.     

Diets of two sympatric colobines in Zaire: More evidence on seed-eating in forests on poor soils

Recent studies have shown that the so- called folivorous African colobines eat a significant amount of seeds. There is disagreement as to whether seed-eating is due to the poor quality of tree foliage, due in turn to poor soils, or to the fact that seeds are a normal part of colobine diets. To test these hypotheses, we studied feeding of red colobus monkeys, Colobus badius tholloni,and black-and-white colobus monkeys, Colobus angolensis angolensis,in a tropical rain forest of Central Zaire (Salonga National Park). We conducted studies on soil properties, vegetation composition, and the availability and chemical contents of food plants simultaneously. Soils were very acid, with a high percentage of sand, very low cation exchange capacity, and very low exchangeable bases. The forest was dominated by legumes (45.6% of trees), among which the Caesalpinioideae were the best represented (85%). C. badiusfed mostly on leaves (61%) and seeds (33%), legumes making up 65% of their diet. C. angolensisfed mostly on seeds (50%) and leaves (27%); 39% of their diet came from legumes. The two species tended to select items richer in crude protein or lipids or both. Total phenolics and condensed tannins were abundant in the foliage and seeds but were poor predictors of colobine choice of food. Intersite comparisons show that colobines in Zaire ate a higher proportion of seeds than all other related species so far studied in Africa and that the Salonga forest had among the poorest soils and harbored the highest percentage of Caesalpinioideae. Our results confirm that seed- eating is more common among colobines living in areas where soils are poor. They strongly suggest that this link is mediated through forest composition, especially the abundance of legumes, and that the development of seed- eating results both from the high availability of nutrient-rich seeds and from the poor quality of mature tree foliage.     

Taste areas of the plica sublingualis of Alouatta and Aotus (Primates,Platyrrhini)

A conspicuous accumulation of taste buds occurs in the rostral part of the plica sublingualis ("frenal lamella") of Alouatta and Aotus forming taste areas (area gustatoria) superficially situated in the oral mucous membrane. They are found in close vicinity to the orifices of the sublingual salivary glands, but are lacking in the aboral part of the plica sublingualis. They do not occur in all primate species studied. A taste area does not projects above the surface of the surrounding tissue like a papilla. The taste buds open not in crypts of furrows of the oral mucosa, but directly into the spatium sublinguale of the oral cavity proper. In the anterior part of the cavum oris proprium different kinds and very differentiated qualities of sensoral information are perceived (touch, olfaction, temperature). It is conceivable that the taste areas play an important role in perceiving fresh saliva, together with the other sensorial structures in this part of the mouth. This problem can be solved experimentally and by behavioral studies, In addition to its topographical relation to the tongue, the organon sublinguale of Callicebus is structurally very similar to the plica sublingualis of Aotus and Alouatta. Since a sublingua does not occur in New World monkeys, it can be concluded that this organ represents a plica sublingualis which became adherent to the undersurface of the tongue.     

Coping with Forest Fragmentation: The Primates of Kibale National Park,Uganda

A goal of conservation biology is to determine which types of species are most susceptible to habitat disturbance and which types of disturbed habitats can support particular species. We studied 20 forest fragments outside of Kibale National Park, Uganda, to address this question. At each patch, we determined the presence of primate species, tree species composition, patch size, and distance to nearest patch. We collected demographic, behavioral, and dietary data for Abyssinian black-and-white colobus (Colobus guereza). Black-and-white colobus and red-tailed guenons (Cercopithecus ascanius) were in almost all fragments; Pennant's red colobus (Procolobus pennantii) and chimpanzees (Pan troglodytes) were in some fragments; and blue monkeys (Cercopithecus mitis) and gray-cheeked mangabeys (Lophocebus albigena) were absent from all fragments. No species characteristics—home range, body size, group size, or degree of frugivory—predicted the ability of species to live in patches. No characteristics of patches—area, distance to the nearest patch, distance to Kibale, or number of food trees present—predicted the presence of a particular species in a patch, but distance to Kibale may have influenced presence of red colobus. Black-and-white colobus group size was significantly smaller in the forest patches than in the continuous forest of Kibale. For a group of black-and-white colobus in one patch, food plant species and home range size were very different from those of a group within Kibale. However, their activity budget and plant parts eaten were quite similar to those of the Kibale group. The lack of strong predictive variables as well as differences between other studies of fragmentation and ours caution against making generalizations about primate responses to fragmentation.     

RFLP-based phylogeny of Musa species in Papua New Guinea

Summary Random genomic probes were used to detect restriction fragment length polymorphisms (RFLPs) in 26 accessions of Musa representing eight species from Papua New Guinea (PNG), M. textilis, M. jackeyi and one accession of Ensete. Ninety-eight phylogenetically informative characters were scored and analyzed cladistically and phenetically. Results generally agreed with previous morphology-based phylogenetic analyses. However, the closest wild relative of the edible M. fehi (fe'i banana) appears to be M. lolodensis. Musa angustigemma is sister species with M. boman and M. jackeyi and is distinct from M. peekelii, with which it is often united. Musa boman is unambiguously placed in section Australimusa. The diploid parthenocarpic landraces of section Musa unique to PNG are closely related to, but apparently distinct from, M. acuminata ssp. banksii. The evolution of the fe'i bananas and the M. acuminata-derived diploid landraces of PNG are discussed.     

New and noteworthyHabenaria spp. (Orchidaceae) from New Guinea and adjacent islands

5 new taxa ofHabenaria, namelyH. bougainvillae, H. elongataR. Br. var.leptophylla, H. ensigera, H. rechingeri andH. trichoglossa, are described and illustrated, with reference to affinities to related Australian and Indo-malayan species. The occurrence in New Guinea of severalHabenaria spp. typical for a savanna-like vegetation, led to look more thoroughly at these taxa:H. elongataR. Br. andH. ochroleucaR. Br., considered so far to be endemic in Northern Australia, andH. khasianaHook. f., hitherto only known from southeastern Asia.Studies in the subtribeHabenariinaeBentham (Orchidaceae), 2.—Part 1: Candollea34, 357 (1979).Dedicated to Hofrat Prof. DrKarl Heinz Rechinger on the occasion of his 80th birthday. — On April 30, in the year 1927, the author and his brotherOtto Renz metKarl Heinz Rechinger on a small steam-boat in a stormy Aegaen Sea, travelling from Piraeus to the Northern Sporades Islands:Karl Heinz with destination to Chelidromia, the author andO. Renz to Skopelos. By this lucky chance a lasting friendship began.     

Identification of cultivated Pandanus and Colocasia in pollen records and the implications for the study of early agriculture in New Guinea

Pollen records from the island of New Guinea, spanning the last 60 000 years, show a vegetation system sensitive to global climate change and strongly influenced by anthropogenic activity. The evidence for anthropogenic activity in pollen diagrams has focused on indirect indicators such as forest clearance, burning and increases in arable weeds. Tracing individual cultivars has proven to be very difficult as the major cultivated plants, in this case dominated by root crops, have low pollen production, are insect-pollinated or are harvested before flowering occurs. The identification of some cultivars is further restricted by limited information on pollen morphology. The pollen morphology of selected species from two genera (Pandanus and Colocasia), known to include important cultivated species, have been studied. Five pollen taxa are recognised after examination by light microscopy and scanning electron microscopy. It is shown that these can be easily distinguished on the broad criteria of pollen class, grain size and size of echini. The taxonomic and dispersal characteristics of the pollen morphology of these taxa are discussed and the implications of improved identification of cultivated species in late Quaternary pollen records are considered.     

Effect of mound size and fertilizer on white Guinea yam (Dioscorea rotundata) in Southern Nigeria

Summary Field trials were conducted in the forest zone of southern Nigeria on three soil series, gravelly loamy sand Ibadan soil (Oxic paleustalf), gravelly sandy loam Egbeda soil (Oxic paleustalf) and sandy loam Alagba soil (Oxic paleustalf). The trials were carried out to study the effects of planting on flatversus various mound sizes and NPK fertilizer on performance of white Guinea yam (Dioscorea rotundata) cultivar Laoko.Mound size appeared to have a more pronounced effect on tuber yield than fertilizer even on land which was in the second and third year of cropping after bush fallow. The average tuber yield for the three locations without fertilizers was 7.83 tons/ha on the flat compared with 9.44 tons/ha on large mound (about 30 cm height). With fertilizer application, tuber yields were 7.43 tons/ha on the flat and 11.30 tons/ha on large mound respectively. Total yield reduction on flat may in part be related to physical soil impedence. Planting on large mounds also resulted in longer tubers and shorter harvesting time.     

Insectivory in free-ranging bearded saki (Chiropotes satanas chiropotes)

Bearded saki are considered frugivores primarily specialized for the predation of immature seeds. I report the first observations of wildC. s. chiropotes actively feeding on immature or non-volant insects in the canopy of upland (“terra firme”) rain forest, in Amazonas, Brazil. During one year of field study I recorded 20 insectivory feeding bouts: 18 times on lepidopteran larvae, 1 time on coleopteran larvae, and 1 time on adult ants.     

Palm wine harvesting by the Bassari threatens Borassus aethiopum populations in north-western Guinea

The use of the palm tree Borassus aethiopum Mart(Coryphoideae) by the Bassari ethnic group in the Republic of Guinea wasstudied. Ethnic groups have multiple uses for B. aethiopumthroughout its distribution in tropical Africa. The Bassari use this palm mostlyas a palm wine resource. As their harvesting technique leads to the death of thepalm, the populations of this species are highly endangered in the areapopulated by the Bassari. The fast decline of an important resource has recentlygained attention at governmental level. In order to conserve the populations ofthis palm, it is essential to understand whether the Bassari use a lethaltechnique because of socio-economic reasons or due to a lack of knowledge. Thepresent study aims to answer this question. We collected the data in thenorth-western part of the Republic of Guinea in May 1996 by field observationsand by using 'Rapid Rural Appraisal' tools consisting of interactiveinterviews with palm wine harvesters, collectors, carriers and sellers. Afterconstructing a woody ladder fixed to the stem the Bassari extract the sap bycutting a hole into the palm heart and by removing a small part of the palmheart two times per day. Individual trees produce on average 10 lper day. After 35–45 days the sap production ceases and thepalm dies. A harvester kills on average 56 individuals of B.aethiopum per year. As a consequence of this lethal techniqueexploiters have to constantly move through and between palm populations. Thereis no reforestation of the degraded areas. The palm wine extraction ofB. aethiopum is the main activity of the Bassari for 7months of the year. For harvesters, collectors, carriers andsellers, palm wine extraction provides one of the most important annual incomes.The harvester pays a monthly tax of USD 5 to the forestry administration.Despite its economic importance, the Bassari palm wine harvesters rangeB. aethiopum as the sixth most important plant species in the area. The paradoxical situation of acommunity that threatens a resource that it is highly dependent on may beexplained by the following circumstances. Firstly, the exploiters seek a maximumprofit on a short term basis. Secondly, the exploiters apparently do not takeinto consideration the total value of other potential products from theBorassus. Thirdly, the Bassari do not have an importanttradition for exploiting B. aethiopum so that there is noapparent cultural alliance between the Bassari and the palm. Finally, the rulesand regulations for harvesting Borassus products favourquick profit. The extinction of the palm population studied can be expectedwithin about 25 years if no protection measure is taken.     

The genusIschnea (Asteraceae,Senecioneae) in New Guinea

The endemic New Guinean genusIschnea F. Muell. (Asteraceae, Senecioneae, Blennospermatinae) is revised and four species are recognized. Characters of special interest are tubeless ray florets, male disc florets, and secretory spaces in leaves. A principal component analysis is made on theIschnea elachoglossa F. Muell. complex which shows great variation. One new species,I. capellana Swenson, from the Star Mountains, is described. A key, illustrations, and distribution maps to all species are supplied.     

Preliminary survey of the distribution and population of chimpanzees in the Republic of Guinea

An investigation of the distribution and population of chimpanzees in the Republic of Guinea was carried out with the help of the Government authorities on the basis of a questionnaire. As a result, at least 20 out of the 36 prefectures in the country were confirmed to be inhabited by chimpanzees, and the estimated total number of animals in the present population amounted to 6,625. This number represented an approximately 50% reduction from the 13,940 estimated by the same informants on the same questionnaire based on assumptions for the past (20–60 years ago). On comparing these data with our observations in some localities, the present number of chimpanzees as estimated from the questionnaire appeared to be overestimated. Among the 16 other prefectures without any reply, at least 7 have chimpanzees according to our own and our colleagues' observations. On our modest estimate, the number of chimpanzees at present could be only about 1,420 for 30 prefectures rather than 6,625 for 20 prefectures. The true population size in the whole country may lie between the two estimates, 1,420–6,625, even including other prefectures with no information. The reduction in population size during the last 20–60 years must be half or even more. The reason for this drastic reduction of the chimpanzee population is thought to be mainly the destruction of its habitat and poaching in some prefectures adjacent to Sierra Leone and Liberia. These findings emphasize that urgent efforts need to be directed towards the conservation of the chimpanzees and their habitat, especially through international cooperative programmes.