Group Of Macaques Research Articles

Behavioral responses of free-ranging Japanese macaques (Macaca fuscata) to sudden loud noises.

We opportunistically observed 31 cases of responses to sudden loud noises mainly caused by falling rocks and trees in a free-ranging, provisioned group of Japanese macaques, Macaca fuscata, at Katsuyama, Japan, and analyzed 27 cases for which we successfully recorded their responses. In 88% of the 24 cases in which the highest- or second-highest ranking adult male probably heard the noise, one or both of them vocalized aggressively in response. Other males tended to vocalize when they were far away from the two highest-ranking males (in 5 of 7 cases in which they vocalized). Adult females vocalized in only 8% of cases, even when they fled from the noise source. These findings suggest that, unlike tree-shaking and female-directed aggression- both performed often in the mating season and accompanied by vocalizations in both high- and low-ranking males of Japanese macaques- vocalizing in response to sudden loud noises is usually limited to one or two high-ranking males in the vicinity. This vocal response could be a way for the males to advertise their social status; it may also serve to calm group members scared by the noise, preventing them from fleeing in panic and dispersing widely. Our observations also suggest that males may monitor which other males remain nearby, and that whereas females may scream in response to socially induced fear, they are least likely to do so in response to fear arising from non-social contexts.

Phylogeography of the Sinica Group of Macaques in the Himalayas: Taxonomic and Evolutionary Implications.

Owing to the taxonomic incongruence between the morphological features and genetic relationships of the sinica group of macaques (genus Macaca), the taxonomy of this macaque group has remained inconclusive. We aimed to resolve the taxonomic quandary and improve our understanding of the historical biogeography of the group by including macaque DNA samples from previously unsampled areas in the Himalayas. We sequenced and analyzed three mitochondrial DNA loci [cytochrome b (CYTB), cytochrome oxidase subunit 1 (COI) and D-loop; 2898 bp] for sequence polymorphism, phylogenetics, species delimitation, and ancestral area reconstruction. We confirmed the occurrence of Arunachal macaque (Macaca munzala) on the southern slopes of the Eastern Himalayas in the Xizang Zizhiqu (Tibet Autonomous Region) of China. The results revealed that the sinica group of macaques is a parapatric species group composed of seven distinct species. Phylogenetic and species delimitation analyses revealed that the two previously considered subspecies of Assamese macaques (the eastern subspecies M. assamensis assamensis and the western subspecies M. a. pelops) are two distinct species. The eastern Assamese macaque is a sister species to the Tibetan macaque, whereas the western Assamese macaque and Arunachal macaque are the closest genetic sister species. The sinica group of macaques underwent five vicariance and seven dispersal radiations in the past, which mainly coincided with the Quaternary climatic oscillations between the late Pliocene and the late Pleistocene. By integrating our phylogenetic and ancestral area reconstruction results with findings from previous paleontological and molecular studies, we propose a robust hypothesis about the phylogeography of the sinica group of macaques.

Brief Report on The Population Survey Long-tailed Macaque (Macaca fascicularis [Raffles,1821]) in West Nusa Tenggara, Indonesia

Survey on the population and distribution of long-tailed macaque (Macaca fascicularis [Raffles, 1821]) in the administrative areas of West Nusa Tenggara Province have been conducted during June-July 2024 to examine the distribution and population status on the macaque. The on-road reconnaissance survey, interview and literature studies have applied to collect data. We recorded 6146 individuals from 307 groups of long-tailed macaques in eight regencies. Of the 6146 individuals of long-tailed macaques, 1532 individuals are recorded living in conservation area, while 4614 individuals live in outside conservation area, respectively. The number of individuals and troops of the monkey showed us the minimum number that can be recorded. Further study needs to be conducted in addressed to dig more information on the existence of long-tailed macaque in West Nusa Tenggara. Furthermore, population information and distribution of long-tailed macaques could be the basic knowledge on the population management efforts in the future.

Male consort behavior is driven by female mate choice and receptive synchrony in Tibetan macaques (Macaca thibetana)

In group-living animals, males’ fighting abilities were usually mediated via dominance rank to sort males into a queue to access fertile females, especially in non-human primates. However, the correlation between male reproductive success and consortship, an alternative high-ranking male reproductive strategy, varies across species, obscuring the adaptive significance of male consort behavior. The priority of access (PoA) model is commonly used to predict male mating/reproductive success based on male dominance rank and female reproductive synchrony. In this study, we aimed to assess the applicability of the PoA model in predicting the distribution of male mating success and consortship, while also identifying the main factors influencing these outcomes in a group of free-ranging Tibetan macaques (Macaca thibetana) at Huangshan, China. Our results showed that (1) the male mating was significantly skewed towards the highest-ranking males, deviating from the expectations set by the PoA model. This departure was attributed to both female mate choice and male consort behavior. Notably, the influence of male rank on mating success decreased as the number of receptive females increased. Additionally, female mate choice became less significant when consorted by males compared to situations when they were not consorted; (2) the observed consort behavior among males was lower than what the PoA model predicted for available receptive days, while high-ranking males exhibited a gradual increase in their consort behavior with the rising number of receptive females. Our results suggests that, in Tibetan macaques, male consort behavior imposed limitations on female mate choice, and mitigated the impact of male dominance rank on male mating success as the number of receptive females grew. We propose that male consort behavior could be driven by female counter-monopoly strategies, and the simultaneous occurrence of consort behavior and opportunistic mating may represent the most effective mating tactic in this promiscuous mating system.

Maternal rejection but not protectiveness predicts juvenile Japanese macaque behavior without direct maternal influence.

Primates show large interindividual variability in the character and quantity of interactions between mothers and their immature offspring. Multiple studies have documented associations between maternal behavior and the occurrence or frequency of certain behaviors among offspring, but it remains unclear whether and how early maternal interactions generally affect behavioral development in offspring. We followed two wild groups of Japanese macaques on Yakushima island and investigated the relationship between maternal behavior and several types of behavior performed by 35 juvenile offspring. We further asked if the impact of maternal behavior on juvenile behavior persists regardless of the distance between mother and offspring, testing whether the influence extends beyond cases when the mother is nearby. We found that juveniles whose mothers frequently rejected them approached and played with others more often, independent of their mother's presence. Juveniles of more protective mothers were in proximity to fewer other individuals and played less, but only if their mothers were nearby. Maternal rejection appears to exert a generalized effect on offspring behavior that endures when mothers are absent. In contrast, effects of maternal protectiveness may be temporary and/or reflect direct maternal influences, such as active intervention in offspring interactions, or effects of the mother's own social relationships on offspring interactions. Our results suggest that understanding how maternal behavior affects offspring development requires paying attention to the context of juvenile behavior, including the mother's distance from her offspring.

Facial expressivity in dominant macaques is linked to group cohesion.

Social living affords primates (including humans) many benefits. Communication has been proposed to be the key mechanism used to bond social connections, which could explain why primates have evolved such expressive faces. We assessed whether the facial expressivity of the dominant male (quantified from the coding of anatomically based facial movement) was related to social network properties (based on social proximity and grooming) in nine groups of captive rhesus macaques (Macaca mulatta) housed in uniform physical and social environments. More facially expressive dominant male macaques were more socially connected and had more cohesive social groups. These findings show that inter-individual differences in facial expressivity are related to differential social outcomes at both an individual and group level. More expressive individuals occupy more beneficial social positions, which could help explain the selection for complex facial communication in primates.

Activity budget and habitat use in the Nicobar long-tailed macaque Macaca fascicularis umbrosus

Time-activity budget and pattern of habitat use are basic tools to understand an animal’s interaction with its environment. We studied a primarily commensal group of long-tailed macaques (Macaca fascicularis umbrosus) with 22 individuals in the Great Nicobar Island of India at Campbell Bay. Data on the frequency and duration of different activities were collected through scan sampling and ad libitum notes. We recorded the geo-coordinates of the visually approximated group center using a handheld GPS receiver (Garmin GPS Map 76csx) every 30 min to assess the ranging patterns. The group spent more time resting, followed by feeding, social behaviours, movement, foraging, and scouting. The time spent on various activities did not vary at different times of the day and showed no seasonal variations. The macaques fed mostly on the cultivated fruits. Although the total home range size was 66ha, the most frequently used area was only 6 ha. The macaques ranged over a larger area in the dry season than in the wet season. All these patterns show that the behaviour of the study group was typical of that of the commensal macaques of other species.

Consistent Individual Differences Drive Collective Movements in a Tibetan Macaque Group

Collective movement has emerged as a key area of interest in animal behavior. While individual differences are often viewed as a potential threat to group cohesion, growing evidence suggests that these differences can actually influence an animal’s behavior as an initiator or follower during collective movements, thereby driving the group‘s movement and decision-making processes. To resolve the divergence, we asked how personality can affect the dynamics of collective movements in one group of free-ranging Tibetan macaques (Macaca thibetana) in Huangshan, China. We assessed individual personality using principal component analysis and applied the generalized linear mixed model and linear mixed model to examine the influence of personality on decision making during collective movements. Our findings reveled three distinct personality types among Tibetan macaques: sociability, boldness, and anxiousness. Individuals with higher sociability scores and rank, or those with lower anxiousness scores, were more likely to initiate successful collective movements. Older individuals were less successful in initiating movements compared to young adults. Leaders with lower anxiousness scores or higher rank attracted more followers, with females attracting larger groups than males. As for followers, individuals with higher rank tended to join the collective movement earlier. Additionally, individuals with higher sociability or boldness scores had shorter joining latency in collective movement. Finally, there was a longer joining latency for middle-aged adults compared to young adults. These results suggest that individual differences are a potential driver of collective movements. We provide some insights into the relationships between personality and decision making in Tibetan macaques.

Phylogeography and demographic history of macaques, fascicularis species group, in East Asia: Inferred from multiple genomic markers

Climate changes at larger scales have influenced dispersal and range shifts of many taxa in East Asia. The fascicularis species group of macaques is composed of four species and is widely distributed in Southeast and East Asia. However, its phylogeography and demographic histories are currently poorly understood. Herein, we assembled autosomal, mitogenome, and Y-chromosome data for 106 individuals, and combined them with 174 mtDNA dloop haplotypes of this species group, with particular focus on the demographic histories and dispersal routes of Macaca fuscata, M. cyclopis, and M. mulatta. The results showed: (1) three monophyletic clades for M. fuscata, M. cyclopis, and M. mulatta based on the multiple genomics analyses; (2) the disparate demographic trajectories of the three species after their split ∼1.0 Ma revealed that M. cyclopis and M. fuscata were derived from an ancestral M. mulatta population; (3) the speciation time of M. cyclopis was later than that of M. fuscata, and their divergence time occurred at the beginning of “Ryukyu Coral Sea Stage” (1.0–0.2 Ma) when the East China Sea land bridge was completely submerged by the sea level rose; and (4) the three parallel rivers (Nujiang, Lancangjiang, and Jinshajiang) of Southwestern China divided M. mulatta into Indian and Chinese genetic populations ∼200 kya. These results shed light on understanding not only the evolutionary history of the fascicularis species group but also the formation mechanism of faunal diversity in East Asia during the Pleistocene.

The Impacts of COVID-19 Lockdown on Human–Primate Coexistence: Insights and Recommendations

The global outbreak of the COVID-19 pandemic has led to a series of human lockdowns. Studying human–animal linkages during these periods is essential in conserving global biodiversity, maintaining ecosystem integrity, and preventing zoonotic diseases. This especially applies to the matters between human and nonhuman primates—their coexistence. In this study, we used community interviews and camera traps to analyze behavioral responses and changes in human–monkey relationships regarding a semi-wild group of macaques ( Macaca mulatta ) in a tourism area during the lockdown. The results indicate that food provision for macaques from tourists substantially declined. As a result, macaques moved to communities for food, causing increased human–monkey conflicts; consequently, local communities’ attitudes toward macaques prominently changed: those who have experienced severe conflicts are far less tolerant of the macaques than those without experience. Thus, to maintain a cordial coexistence between humans, primates, and other animals in ecotourism areas, we suggest (a) establishing long-term monitoring to maintain a sustainable balance between animal population size and available food resources provided by humans and the environment; (b) improving emergency management policies for controlling monkey populations to prevent the unwanted conflicts between macaques and communities, responding to exceptional circumstances such as the COVID-19 lockdown; (c) strengthening the establishment of conduct code for tourists to avoid conflicts between tourists and primates and the spread of pathogens; and (d) upgrading compensation policies for the damages caused by human–wildlife conflicts and strengthening the cooperation between the community and tourist management; an amicable relationship between communities, economic development, and animal conservation is highly demanded.

Thermostable bivalent filovirus vaccine protects against severe and lethal Sudan ebolavirus and marburgvirus infection

Although two vaccines for Zaire ebolavirus (EBOV) have been licensed and deployed successfully to combat recurring outbreaks of Ebolavirus Disease in West Africa, there are no vaccines for two other highly pathogenic members of the Filoviridae, Sudan ebolavirus (SUDV) and Marburg marburgvirus (MARV). The results described herein document the immunogenicity and protective efficacy in cynomolgus macaques of a single-vial, thermostabilized (lyophilized) monovalent (SUDV) and bivalent (SUDV & MARV) protein vaccines consisting of recombinant glycoproteins (GP) formulated with a clinical-grade oil-in-water nanoemulsion adjuvant (CoVaccine HT™). Lyophilized formulations of the vaccines were reconstituted with Water for Injection and used to immunize groups of cynomolgus macaques before challenge with a lethal dose of a human SUDV or MARV isolate. Sera collected after each of the three immunizations showed near maximal GP-binding IgG concentrations starting as early as the second dose. Most importantly, the vaccine candidates (monovalent or bivalent) provided 100% protection against severe and lethal filovirus disease after either SUDV or MARV infection. Although mild, subclinical infection was observed in a few macaques, all vaccinated animals remained healthy and survived the filovirus challenge. These results demonstrate the value that thermostabilized protein vaccines could provide for addressing an important gap in preparedness for future filovirus outbreaks.

Healing Hanuman's Army: Veterinary Care as a Core Component of One Health Principles in a Southeast Asian Monkey Forest.

Wildlife that inhabit urban landscapes face the dual challenge of negotiating their positions in their group while navigating obstacles of anthropogenically modified landscapes. The dynamics of urban environments can result in novel injuries and mortalities for these animals. However, these negative impacts can be mitigated through planning, and onsite veterinary care like that provided by the Ubud Monkey Forest in Bali, Indonesia. We examined 275 recorded injuries and mortalities among six social groups of long-tailed macaques (Macaca fascicularis) brought to the veterinary clinic from 2015-2018. We fit the probabilities of injury vs. death among macaques brought to the clinic using a multilevel logistic regression model to infer the relationship between injury vs. death and associated demographic parameters. Males were more likely to sustain injuries and females were more likely to die. The frequency of injuries and mortalities changed over the four-year study period, which was reflected in our model. The odds of mortality were highest among young macaques and the odds of injury vs. mortality varied across the six social groups. We categorized injuries and mortalities as "natural" or "anthropogenic". Most injuries and mortalities were naturally occurring, but powerlines, motorized vehicles, and plastic present ongoing anthropogenic threats to macaque health. Most wounds and injuries were successfully treated, with healthy animals released back to their group. We suggest other sites with high levels of human-alloprimate interplays consider the Ubud Monkey Forest veterinary office as a model of care and potentially adopt their approaches.

Characteristics of sleeping sites and sleeping trees selected by Celebes crested macaques (Macaca nigra) in Tangkoko, North Sulawesi, Indonesia

Abstract. Qomariyah IN, Perwitasari-Farajallah D, Iskandar E, Berthier JM. 2023. Characteristics of sleeping sites and sleeping trees selected by Celebes crested macaques (Macaca nigra) in Tangkoko, North Sulawesi, Indonesia. Biodiversitas 24: 6200-6208. Research on the selection of sleeping sites is imperative in providing information on the fitness and survival of a species. We investigated the characteristics of the sleeping sites and the sleeping trees selected by wild Celebes crested macaques (Macaca nigra Desmarest 1822) in North Sulawesi, Indonesia, as well as their spatial and temporal use. The study was conducted in two groups of macaques for nine months (187 study days) from September 2020 to June 2021. These macaques avoided using the same sleeping site on consecutive nights. Two predator encounters (Python reticulatus Schneider 1801) were recorded near the sleeping sites, but pythons caught no monkeys during the study period. The macaques used 58 trees from 13 species as sleeping trees, of which 79% of the sleeping trees were also food trees. M. nigra chose sleeping trees with higher diameter, height, and a bigger Important Value Index than the surroundings. The average distance between sleeping trees and feeding trees in the morning and evening were 203 m and 127 m, respectively. These results suggest that optimal foraging strategy and predator avoidance are important factors in selecting sleeping sites, providing a broader understanding of the habitat preferences of the Critically Endangered M. nigra.

Heterologous prime-boost immunization induces protection against dengue virus infection in cynomolgus macaques.

Currently licensed dengue vaccines do not induce long-term protection in children without previous exposure to dengue viruses in nature. These vaccines are based on selected attenuated strains of the four dengue serotypes and employed in combination for two or three consecutive doses. In our search for a better dengue vaccine candidate, live attenuated strains were followed by non-infectious virus-like particles or the plasmids that generate these particles upon injection into the body. This heterologous prime-boost immunization induced elevated levels of virus-specific antibodies and helped to prevent dengue virus infection in a high proportion of vaccinated macaques. In macaques that remained susceptible to dengue virus, distinct mechanisms were found to account for the immunization failures, providing a better understanding of vaccine actions. Additional studies in humans in the future may help to establish whether this combination approach represents a more effective means of preventing dengue by vaccination.

Gastro-intestinal parasites of urban rhesus macaques (Macaca mulatta) in the Kathmandu Valley, Nepal

Intestinal parasitic infections such as amoebiasis, ascariasis, hookworm infection, and trichuriasis are the most common infections among non-human primates (NHPs). There are always the possibilities of transmission these parasites between humans and NHPs. Multiple groups of rhesus macaques (Macaca mulatta) live in the urban area of Kathmandu Valley near human settlements, however the gastrointestinal (GI) parasitic infections in those macaques are understudied. This study aimed to explore the GI parasites in free-ranging macaques from Pashupatinath, Swayambhunath, Tripureshwor, Nilbarahi temples and a group of captive rhesus macaques in the Central Zoo, Kathmandu. Fecal samples were collected from the macaques between October 2021 to September 2022 and assessed for parasites by the both wet mount method and concentration technique. There is high prevalence of GI parasite infection; out of 121 fecal samples examined, 87.6% of samples were positive. Six species of protozoans and eight species of helminths were identified from the fecal samples including the first report of Iodamoeba butschlii in monkeys of Nepal. Among the protozoan parasites, Entamoeba coli (54.71%) showed the highest prevalence followed by Balantioides coli (44.33%), E. histolytica (19.81%), and Iodamoeba butschlii (10%). Among the helminths, Trichuris spp. (31.13%) and Strongyloides spp. (31.13%) showed the highest prevalence followed by Hookworm (24.52%), and Strongyle spp. (23.58%). The likelihood ratio test suggested that the prevalence differed significantly with the seasons for Iodamoeba butschlii, Giardia spp., Strongyles spp., Hookworm, and Trichostrongylus spp. The prevalence of E. histolytica, E. coli, Iodamoeba. butschlii, Trichuris spp., Trichostrongylus spp., and Unknown spp.1 differed with sampling localities. The high prevalence of GI parasites found in the macaques living in the densely urbanized Kathmandu presents a potential threat to humans and warrants further study as well as increased education of the public and management of the human-macaque interface in the urban landscape of the Valley.

Analysis of IFN-γ and CD4+ responses in comorbid and adult immunized cynomolgus monkey with inactivated SARS-CoV-2 vaccine candidate

Context: Vaccination as prevention to hold back the spread of COVID-19 is important since it is the most concerning health issue in the last decade. Inactivated vaccine platforms considered safer, especially for elderly and comorbid patients. Comorbidities especially Tuberculosis and Hepatitis B, has a major impact to COVID-19 infections and vaccination. To evaluate infections or vaccine response IFN- γ and CD4+ are important. IFN-γ has a role in antiviral innate response, including initiation of other cytokines, increasing MHC expression, increasing presentation of macrophage, and increasing presentation of antigen to T cell Naïve. CD4+ is associated with humoral immune response. Cynomolgus Monkey or known as Macaca fascicularis. Specifying to comorbid patients, adult Macaca fascicularis that are detected to have hepatitis B and Tuberculosis (TBC) by PCR were treated as a comorbid group. Adult Macaca fascicularis that used in this research have range from 6 to 9 years old. This study was analysed with SPSS 26 general linear model repeated measures analysis with p<0.05 Objectives: To evaluate IFN- γ and CD4+ response of vaccination Result: The result of this study showed significant (p < 0.05) increase in IFN-γ and CD4+ evaluation in both comorbid and adult groups. The elevating concentration and percentage could be the sign of induced humoral and adaptive immune system in the body. Conclusion: SARS-CoV-2 inactivated vaccine candidate that used in this study can increase the number of IFN-γ concentration as well as percentage of CD4+ in adult and comorbid groups of Cynomolgus Macaques.

The impact of housing on birth outcomes in breeding macaque groups across multiple research centers.

Demand for nonhuman primates in research has increased over the past several years, while nonhuman primate supply remains a challenge in the United States. Global nonhuman primate supply issues make it increasingly important to maximize domestic colony production. To explore how housing conditions across primate breeding colonies impact infant survival and animal production more broadly, we collected medical records from 7959 rhesus macaques (Macaca mulatta) and 492 pigtail macaques (Macaca nemestrina) across seven breeding facilities and used generalized mixed-effect modeling to determine prenatal and infant survival odds by housing type and group size. Infant survival odds for each housing type and group size varied for prenatal, neonatal, early infant, and late infant age groups. Odds of prenatal survival were lowest in paired indoor housing and small and medium outdoor groups. No housing type performed better than large outdoor groups for neonatal survival. Odds of early infant survival was greatest in indoor and mixed indoor/outdoor housing compared to large outdoor enclosures. Large outdoor housing was associated with higher survival odds for late infant survival compared to small and medium outdoor housing. These results may influence housing choices at macaque breeding facilities hoping to maximize infant success, although there are relative care costs, the promotion of species-typical behaviors, and infrastructure factors to also consider. Our study used an interinstitutional collaboration that allowed for the analysis of more infant macaque medical records than ever before and used the broad variations across the seven national primate research centers to make the results applicable to many other facilities housing macaques.

Effects of Tourist and Researcher Presence on Fecal Glucocorticoid Metabolite Levels in Wild, Habituated Sulawesi Crested Macaques (Macaca nigra).

Ecotourism managers and researchers often assume that apparently habituated primate groups no longer experience adverse consequences of prolonged exposure to tourists or researchers. We examined the effects of tourists and researchers on fecal glucocorticoid metabolite output (FGCM) in three critically endangered, wild crested macaque (Macaca nigra) groups in Tangkoko Nature Reserve, Sulawesi, Indonesia. We assayed FGCM from 456 fecal samples collected from thirty-three adults. Tourists can walk through and among macaque groups freely. Hence, we examined the possible effects of tourists both (1) in the reserve when away and not interacting with the study groups and (2) when they were present within the macaque groups. Generalized Linear Mixed Model (GLMM) analysis indicated that when tourists were present in the forest, but not directly among the macaques, FGCM levels in the macaque tourism groups were higher in months with more tourists. When tourists were among the macaque groups, some female macaques experienced rises and subsequent postexposure decreases in FGCM levels, consistent with predictions for acute stress. Male FGCM levels increased with tourist numbers within the group. Nevertheless, they were not significantly different from levels during undisturbed or postexposure conditions. FGCM responses related to researchers in groups varied by group, sex, and tourist presence. However, the temporal patterning of FGCM responses showed little evidence of chronic stress from tourism at this site.

Uncovering the Neurobiological Consequences of High-Voltage Electrical Field Exposure on the Visual Working Memory of Macaques and Also Using Spiking Neural Network Model

High-voltage (HV) power transmission lines running near cities and villages can cause severe damage (Mental and physical). Due to the magnetic and electric fields they produce. This study aimed to investigate the effects of high-voltage (HV) electric fields on the spiking neural network model of the brain and biological and behavioral models of visual working memory. To achieve this goal, macaques were studied for their cognitive functions, expression of the NMDA receptor gene, MRI-assisted analysis of brain anatomy, and variations in blood sodium and potassium concentrations. The experimental group of macaques was exposed to a 3kV/m high-voltage field for four hours a day for one month. Computational models were then evaluated using experimental parameters. According to the results, it was observed that being exposed to high-voltage electric fields led to a reduction in the expression of the NMDA receptor gene, as well as a decrease in the levels of Sodium and potassium ions in the blood plasma. Additionally, analysis assisted by MRI showed a decrease in the volume of the hippocampus and amygdala after exposure to the electric field. In conclusion, the results of cognitive, genetic, blood, and MRI tests, along with the spiking neural network model, elucidate the mechanism of the visual working memory deterioration in macaques due to high-voltage electric field exposure.

Distribution of Long-tailed Macaque (Macaca fascicularis) in Deli Island, Pandeglang, Banten

Deli Island is one of the habitats for the long-tailed macaque (Macaca fascicularis) outside its natural distribution. Not much is known about the existence of Deli Island, included information on habitat use. This study was conducted to determine the distribution and distribution pattern of long-tailed Macaques in utilizing Deli Island as their habitat. The study was conducted in June-July 2022. The study used the transect method and the determination of the waypoint using GPS. Data were analyzed using ArcMap GIS 10.3 program to describe the presence and distribution of long-tailed macaques. The results showed that 27 groups of long-tailed macaques were identified on Deli island spread over several points, large groups were found in fishermen's huts with a total of 42 individuals. This condition illustrates that the distribution pattern of groups of long-tailed macaques on Deli Island is in the random category with nearest neighbor ratio 1,089431.