Third-party vocal intervention in the proboscis monkey (Nasalis larvatus)

Vocal intervention is a triadic social interaction, where a third party responds vocally to a conflict between group members, minimizing the costs of aggression in response to the intervention. Because there is little information on vocal third-party intervention in nonhuman mammals, we investigated whether adult male proboscis monkeys use the bray vocalization as a vocal third-party intervention signal to intervene in intragroup conflicts. First, we audio-recorded 1,811 vocalizations from 17 free-ranging proboscis monkey groups in the Lower Kinabatangan Wildlife Sanctuary, analyzing 378 vocal responses of the adult male to agonistic vocal exchanges (shrieks) of group members. Second, we video- and audio-recorded five habituated groups in the Labuk Bay Proboscis Monkey Sanctuary investigating the context of these vocalizations and the conflict dyads evoking vocal support. We found that adult males of one-male/multifemale groups mainly uttered bray vocalizations, whereas females, immatures, and infants uttered shrieks in intragroup conflicts or in response to other animal species. The adult male uttered significantly more often brays after agonistic shrieks than expected based on the overall occurrence of brays. Brays ended 65% of agonistic conflicts, which were accompanied by vocalizations of the conflict partners and occurred more often after conflicts between females than between offspring. This suggests that the bray functions as a vocal third-party intervention signal for intragroup conflict resolution. We suggest that living in the high canopies of the tropical rainforest might restrict direct access to conflict partners and prevent physical intervention, favoring the evolution of the bray as a third-party vocal intervention signal.

Population of Proboscis Monkey (Nasalis lavatus) in Manggar River, Balikpapan City, Indonesia

A population estimation of proboscis monkeys (Nasalis larvatus) has been conducted in Manggar River, Balikpapan. In this non-conservation area, the anthropogenic activities threaten the proboscis monkey habitat. Boat survey technique was applied along ± 17 km of the river in the morning and evening. The number of proboscis monkeys in the surveyed area was estimated to range from 57 to 69 individuals with estimated population density of 4.75 individuals/Km2. Moreover, the population of this primates was divided into 4 groups and the sex ratio between adult males and females was 1:2.33. The proboscis monkeys were distributed in the middle of the river to the upstream. The highest population was found in the upstream area with less human activities. Conservation efforts in the Manggar River need to be carried out considering the proboscis monkey habitat in the area has been fragmented and isolated. These efforts could involve local economic communities.

A preliminary study on semen collection, its evaluation, and testicular and sperm morphometries in the wild proboscis monkey (Nasalis larvatus)

Introduction The proboscis monkey (Nasalis larvatus) is an endangered species with a declining population. This article describes the first successful attempt at sperm collection and evaluation, and the testicular and sperm morphometries of the wild proboscis monkey in Sabah, Malaysia. Material and Methods Eight semen collection procedures using electro-ejaculation and digital manipulation were conducted in three wild adult male proboscis monkeys. A total of 21 ejaculates were collected. The testicular biometry was measured with the aid of ultrasonography. Sample evaluation included semen volume and pH and sperm concentration, viability, and abnormality. The sperm morphometry was undertaken using phase contrast microscopy. Results The mean (±SD) total testicular volume of these animals was 5.77 cm3 (±1.58). Semen collection by electro-ejaculation resulted in an 84% success rate, while digital manipulation did not result in any ejaculation. Each animal showed different semen characteristics, where the volume was 5–540 μL, pH 8–9, and sperm concentration 0.041–83.00 ×106/mL. The percentage of abnormal sperm was high at 76.8% (±89.60), largely due to midpiece abnormality. Normal sperm had a spherical head and long tail with a head : midpiece : tail length ratio of 1 : 2: 8. Conclusion The social status of these animals may contribute to the generally low quality of the semen. The techniques and data from this study are useful for future conservation and application of assisted reproductive technology in this species.

REKOMENDASI PENETAPAN KAWASAN EKOSISTEM ESENSIAL DI DESA PANJARATAN

Essensial Ecosystem Areas in general can be interpreted as protected areas outside conservation areas. In Panjaratan Village, it is found an area that is a habitat for proboscis monkeys and other animals according to the results of the inventory but is outside the conservation forest area. The existence of proboscis monkey (Nasalis larvatus) habitat in Panjaratan Village needs to supported in conservation so that it does not experience extinction due to interference for human activities. This study aims to provide recommendations in planning the determination of essential ecosystem areas for the Nasalis larvatus habitat in Panjaratan Village. This research was qualitative by using an emic approach that focuses on data and analysis based on answers from key informant. The results showed that the presence of Nasalis larvatus habitat in Panjaratan Village received support from the community, government and the private sector in its empowerment activities. This is supported by the existence of an inventory and verification of the presence of Nasalis larvatus habitat in Panjaratan Village conducted by the South Kalimantan Natural Resource Conservation team and through identification activities to then propose the Nasalis larvatus habitat area in the village to become an area of essential ecosystem areas.

Lactobacillus nasalidis sp. nov., isolated from the forestomach of a captive proboscis monkey (Nasalis larvatus)

Three strains (YZ01T, YZ02 and YZ03) of Gram-stain-positive, facultatively anaerobic rods were isolated from the forestomach contents collected from a captive male proboscis monkey (Nasalis larvatus) at Yokohama Zoo in Japan. Phylogenetic analysis of the 16S rRNA gene sequences revealed that these strains belonged to the genus Lactobacillus . Based on the sequence similarity of the 16S rRNA gene, Lactobacillus delbrueckii subsp. indicus JCM 15610T was the closest phylogenetic neighbour to YZ01T. Sequence analyses of two partial concatenated housekeeping genes, the RNA polymerase alpha subunit (rpoA) and phenylalanyl-tRNA synthase alpha subunit (pheS) also indicated that the novel strains belonged to the genus Lactobacillus . The average nucleotide identity and digital DNA–DNA hybridization (dDDH) between L. delbrueckii subsp. indicus and YZ01T were 85.9 and 31.4 %, respectively. The phylogenetic tree based on the whole genomic data of strains YZ01T, YZ02 and YZ03 suggested that these three strains formed a single monophyletic cluster in the genus Lactobacillus , indicating that it belonged to a new species. The DNA G+C content of strain YZ01T was 51.6 mol%. The major fatty acids were C16 : 0 and C18 : 1 ω9c. Therefore, based on phylogenetic, phenotypic and physiological evidence, strains YZ01T, YZ02 and YZ03 represent a novel species of the genus Lactobacillus , for which the name Lactobacillus nasalidis sp. nov. is proposed with the type strain YZ01T (=JCM 33769T=DSM 110539T).

Model Assessment on Cooling Effect of Mangrove and Proboscis Monkey Conservation Area in Tarakan City

<p><em>A conservation area for mangrove forests and proboscis monkeys locates within a dense urban centre in Tarakan city. Its surrounding area has rapidly transformed into condensing urban artificial structures with minimal vegetation cover. The study aims to determine the cooling effect of the conservation area toward its surrounding. The study applies model assessment, which comprises ENVI-MET for simulation of air temperature distribution, and Rayman for PMV (Predicted Mean Vote) calculation to investigate the level of heat stress. The result shows that the mangrove cover has a cooling effect effectively after midnight to 11:00 the subsequent day. Specifically, for the surrounding area, it is confined within an 8-hour window (from 0:00 to 8:00). Within this window, inside the mangrove area, ENVI-MET generates significantly lower air temperature, when compared to its surrounding. The mangrove presence correlates to reducing air temperature up to 1.8</em><em>°</em><em> C. The cooling effect also extends to its surrounding with a limited radius (approximately 10 m). However, PMV calculation implies that there is no significant improvement in thermal comfort as a result of the mangrove presence. The results may not adequately reflect the reality in the field. Further research to calibrate PMV measurement that involves human monitoring is required to validate the findings.</em></p>

STRUKTUR POPULASI BEKANTAN (NASALIS LARVATUS) DI RAWA GELAM

Number of proboscis monkey population in Cajuputi Swamp Forest is 258 individual. This population is strongly influenced by condition of its habitat which is to degradation to 3.417 hektar. The object of research is to analyzed structure of proboscis monkey population. Method of research are river survey (Sha et al, 2008) and concentration count (Anonymous, 1981; Alikodra, 2002). The avarage density of proboscis monkey in their homerange is 3 individuals/hectares, with 30,2% males and 48,5 % females. This population is slow growth because there is only one baby/year, this is also indicated by number of 14 individuals babies (5,4%) and 41 infant (15,9%) lower when compared to number of adult indiviuals, so it is very worryng for continued growth of the population.

STASIUN RISET BEKANTAN PADA LAHAN BASAH

Wetlands are a natural habitat for endemic animals of South Kalimantan, namely proboscis monkeys (Nasalis larvatus). These primates are one indicator in wetlands conservation, but now the status of proboscis monkeys is endangered which means wetlands are naturally also damaged. This makes The Indonesian Proboscis Monkey Friends Foundation worried about the preservation of these primates who are endangered in a side the number of foreign researchers who are interested in proboscis monkeys so it also weakens status proboscis monkeys as endemic animals.The Indonesian Proboscis Monkey Friends Foundation wants the proboscis monkey in South Kalimantan to become an identity in the area along with the wetland ecosystem which is the habitat of proboscis monkeys. Therefore a fundamental problem with the design of the Proboscis Monkey Research Station on Wetlands is how the design of the proboscis research station on wetlands is in harmony with natural conditions around it so that it can become the identity of the region. Settlement the problem was solved through the metabolism-organic method and the visual identity-metaphor method. The metabolism-organic method is the solution to the problem of harmony building with nature, while the visual identity-metaphor method is the solution in the matter of regional identity. Based on the two methods, the concept proposed for this design is the concept of "subject-object interaction" which is realized through the concept of "wetland ecology". This concept of "subject-object interaction and wetland ecology" is a concept that elevates interactions between researchers and wetland organisms such as proboscis monkeys by entering the wetland elements into the design of this research station.