The ecology of venom use in the Javan Slow Loris (Nycticebus Javanicus) and its implications for conservation

The slow loris Nycticebus spp. belongs to the few venomous mammals. I aimed to explore sources for venom sequestration and the ecological function of slow loris venom, which has never been studied before. I examined the hypotheses that venom is used for intraspecific competition, predator defence and/or (ecto-) parasite avoidance. From April 2012 to June 2013 I observed 12 radio-collared and several uncollared wild Javan slow lorises (N. javanicus) at the rural agricultural field site Cipaganti in West Java, Indonesia. I collected behavioural observations including feeding and ranging data, examined faecal samples for diet remains and parasites, and regularly checked animals for ectoparasites. I also captured arthropods over five months. I monitored the coexistence with potential predator species using camera traps and by conducting forest surveys throughout Java. Venom may be sequestered from secondary plant metabolites and noxious arthropods, as the latter were abundant at the study site. Javan slow lorises fed extensively on gum (56 %) and 95 % of faecal samples contained arthropod remains. With regard to the ecological function, ranging patterns and social interactions indicated that the social system, with a monogamous social organisation and mating system with promiscuous tendencies, has potential for high sexual and non- sexual intraspecific competition. Camera trapping and forest surveys revealed the coexistence of Javan slow lorises with potential predators. However, predator avoidance could not explain the detected lunarphobia in Javan slow lorises. Additionally, animals were surprisingly ectoparasite-free. My results support all three hypotheses explaining the ecological function but should be enforced by analysing the venom composition in relation to various dietary and environmental factors, aided by (behavioural) experiments with potential predator and parasites. Finally, I applied my results to conservation of the Critically Endangered Javan slow loris, providing recommendations for the conservation of wild populations, husbandry of captive animals and reintroduction

Cabinet of curiosities: Venom systems and their ecological function in mammals, with a focus on primates

Venom delivery systems (VDS) are common in the animal kingdom, but rare amongst mammals. New definitions of venom allow us to reconsider its diversity amongst mammals by reviewing the VDS of Chiroptera, Eulipotyphla, Monotremata, and Primates. All orders use modified anterior dentition as the venom delivery apparatus, except Monotremata, which possesses a crural system. The venom gland in most taxa is a modified submaxillary salivary gland. In Primates, the saliva is activated when combined with brachial gland exudate. In Monotremata, the crural spur contains the venom duct. Venom functions include feeding, intraspecific competition, anti-predator defense and parasite defense. Including mammals in discussion of venom evolution could prove vital in our understanding protein functioning in mammals and provide a new avenue for biomedical and therapeutic applications and drug discovery

Impact of climate and moonlight on a venomous mammal, the Javan slow loris (Nycticebus javanicus)

Predation pressure, food availability, and activity may be affected by level of moonlight and climatic conditions. While many nocturnal mammals reduce activity at high lunar illumination to avoid predators (lunarphobia), most visually-oriented nocturnal primates and birds increase activity in bright nights (lunarphilia) to improve foraging efficiency. Similarly, weather conditions may influence activity level and foraging ability. We examined the response of Javan slow lorises (Nycticebus javanicus Geoffroy, 1812) to moonlight and temperature. We radio-tracked 12 animals in West Java, Indonesia, over 1.5 years, resulting in over 600 hours direct observations. We collected behavioural and environmental data including lunar illumination, number of human observers, and climatic factors, and 185 camera trap nights on potential predators. N. javanicus reduced active behaviours in bright nights. Although this might be interpreted as a predator avoidance strategy, animals remained active when more observers were present. We did not find the same effect of lunar illumination on two potential predators. We detected an interactive effect of minimum temperature and moonlight, e.g. in bright nights slow lorises only reduce activity when it is cold. Slow lorises also were more active in higher humidity and when it was cloudy, whereas potential predators were equally active across conditions. As slow lorises are well-adapted to avoid/defend predators by crypsis, mimicry and the possession of venom, we argue that lunarphobia may be due to prey availability. In bright nights that are cold, the combined effects of high luminosity and low temperature favour reduced activity and even torpor. We conclude that Javan slow lorises are lunarphobic – just as the majority of mammals

Software to facilitate and streamline camera trap data management: a review

Improving technology and increasing affordability mean that camera trapping—the use of remotely triggered cameras to photograph wildlife—is becoming an increasingly common tool in the monitoring and conservation of wild populations. Each camera trap study generates a vast amount of data, which need to be processed and labeled before analysis. Traditionally, processing camera trap data has been performed manually by entering data into a spreadsheet. This is time‐consuming, prone to human error, and data management may be inconsistent between projects, hindering collaboration. Recently, several programs have become available to facilitate and quicken data processing. Here, we review available software and assess their ability to better standardize camera trap data management and facilitate data sharing and collaboration. To identify available software for camera trap data management, we used internet searches and contacted researchers and practitioners working on large camera trap projects, as well as software developers. We tested all available programs against a range of software characteristics in addition to their ability to record a suite of important data variables extracted from images. We identified and reviewed 12 available programs for the management of camera trap data. These ranged from simple software assisting with the extraction of metadata from an image, through to comprehensive programs that facilitate data entry and analysis. Many of the programs tested were developed for use on specific studies and so do not cover all possible software or data collection requirements that different projects may have. We highlight the importance of a standardized software solution for camera trap data management. This approach would allow all possible data to be collected, enabling researchers to share data and contribute to other studies, as well as facilitating multi‐project comparisons. By standardizing camera trap data collection and management in this way, future studies would be better placed to guide conservation policy on a global level

High-resolution imaging of basin-bounding normal faults in the Southern Apennines seismic belt (Italy) by traveltime and frequency-domain full-waveform tomography

We apply a two-step seismic imaging flow by combined first-arrival traveltime and frequency-domain waveform tomographies to dense wide aperture data collected in the Val d’Agri basin (southern Italy). A large wavelength Vp model determined by first-arrival traveltime tomography is used as a starting model for waveform tomography. The multiscale waveform tomography consisting of successive inversion of increasing frequencies allows to progressively reconstruct the short wavelengths of the velocity model, providing valuable information on the Quaternary basin and on range-bounding normal-faulting systems

Ecology of Nepenthes clipeata on Gunung Kelam, Indonesian Borneo

Background: Nepenthes clipeata is a Critically Endangered plant species with the population at its only location in the wild, Gunung (Mount) Kelam in Kalimantan, Indonesia, under threat–its nutrient relationships have not been studied. Aims: To improve understanding of the autecology of N. clipeata by assessing the current population and providing information on its mineral nutrient relationships. Methods: A survey was undertaken in 2019 when population numbers and habitat preferences of N. clipeata were recorded. Nutrient concentrations in soil, leaves and pitcher fluid were analysed and compared with those in other Nepenthes species. Results: Eighteen individuals of N. clipeata were found on Gunung Kelam (only one of which was female). Seven other Nepenthes species were found and hybrids with two of these and N. clipeata were observed. Although the foliar nutrient concentrations (‘ionome’) of N. clipeata appeared distinct from that of other Nepenthes species, with N. clipeata having greater nutrient concentrations, particularly nitrogen, potassium and calcium, nitrogen limitation was still prevalent. Conclusions: N. clipeata still persists in the wild but with very low numbers, indicating that conservation actions are required. Along with other species of Nepenthes, it is limited by soil nitrogen concentrations although it has a distinct ionome derived from high foliar nutrient concentrations

The toxicological intersection between allergen and toxin: A structural comparison of the cat dander allergenic protein Fel d1 and the slow loris brachial gland secretion protein

Slow lorises are enigmatic animal that represent the only venomous primate lineage. Their defensive secretions have received little attention. In this study we determined the full length sequence of the protein secreted by their unique brachial glands. The full length sequences displayed homology to the main allergenic protein present in cat dander. We thus compared the molecular features of the slow loris brachial gland protein and the cat dander allergen protein, showing remarkable similarities between them. Thus we postulate that allergenic proteins play a role in the slow loris defensive arsenal. These results shed light on these neglected, novel animals

Slow lorises use venom as a weapon in intraspecific competition

Animals have evolved an array of spectacular weapons, including antlers, forceps, proboscises, stingers, tusks and horns [ 1 ]. Weapons can be present in males and females of species needing to defend critical limiting resources, including food (rhinoceros beetles, Trypoxylus) and territories (fang blennies, Meiacanthus) [ 1 , 2 , 3 ]. Chemicals, including sprays, ointments and injected venoms, are another defence system used by animals. As with morphological weapons, venom can serve multiple purposes, including to facilitate feeding, in predation, and in defence when attacked [ 4 ]. Although rare, several taxa use venom for agonistic intraspecific competition (e.g. ghost shrimp, Caprella spp.; sea anemones, Actinia equina; cone snails, Conidae; male platypus, Ornithorhynchus anatinus) [ 4 , 5 , 6 ]. Another group of venomous mammals are the nocturnal slow lorises ( Nycticebus) [ 7 ]. Slow loris bites often result in dramatic diagnostic wounds characterised by necrotic gashes to the head and extremities. Although these bites are the major cause of death of lorises in captivity, the function of this aggressive behaviour has never been studied in the wild [ 7 ]. Here, through an 8-year study of wounding patterns, territorial behaviour, and agonistic encounters of a wild population of Javan slow lorises ( Nycticebus javanicus), we provide strong evidence that venom is used differentially by both sexes to defend territories and mates

The seasonal feeding ecology of the Javan slow loris (Nycticebus javanicus)

Objectives: To describe the strategy employed by exudativorous primates during seasonal shifts in food abundance using the Javan slow loris as a model. Males and females may cope differently as well as exploit fallback foods in different proportions. Materials and Methods: Observing 15 free ranging Javan slow lorises over a year, we quantified their seasonal diet and nutrient intake using intake rates. We monitored phenology over five plots that were assessed monthly. We weighed animals every six months. We analysed all food items slow lorises ingested for macronutrients using the nutritional geometry framework. Results: The slow loris diet consisted of eight food categories, with gum and insects being the major food source in terms of weight. All food items were available in the wet season and were restricted in the dry season. Males and females reacted differently to seasonal abundances with females ingesting more protein, gum, fruits and flowers and males ingesting more fibre. Discussion: The reproductive costs of gestation and lactation may place a burden on females that requires them to alter their foraging strategy during the dry season to ensure enough protein and overall energy is ingested. The overall strategy used by these exudativorous primates is one of nutrient maximization as no nutrient was clearly preferred over another