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

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

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

Ecology and conservation of the endemic Bawean warty pig Sus verrucosus blouchi and Bawean deer Axis kuhlii

The island of Bawean, Indonesia, is home to the endemic Bawean warty pig Sus verrucosus blouchi and Bawean deer Axis kuhlii. Despite their threatened status, no long-term monitoring programme is in place for either species. Using random encounter and occupancy modelling based on 4,516 camera-trap days in 2014 and 2015 we aimed to provide population estimates and ecological data, including habitat preferences, for these species. For the Bawean warty pig we estimate an overall population size of 234-467 mature individuals and demonstrate a negative correlation between probability of occupancy and distance from villages. This preference for human-modified habitat has implications for human-wildlife conflict and hunting pressure for this species. The population of the Bawean deer could not be estimated because of the low number of encounters, but we suggest that this indicates the population is considerably smaller than previously reported. As island endemics, the Bawean warty pig and Bawean deer are particularly vulnerable to threats, and appropriate measures for safeguarding the species need to be taken.</p

Distinct habitat types found at the study site.

<p>Adapted from Nijman [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0151732#pone.0151732.ref017" target="_blank">17</a>].</p

Model-averaged predicted occupancy (Ψ) in relation to (a) The distance from the nearest border (95% CI = 0.194. -1.040), (b) Litter depth (95% CI = 0.454, -0.146), (c) Altitude (95% CI = 0.179, -0.716) and (d) Tree density (95% CI = 0.304, -0.121).

<p>Predictor variables were log transformed.</p

Top 13 AICc models competing for first ranking model.

<p>Beta coefficients ± standard errors for each covariate are listed. The presence of categorical variables Habitat type and Area in the models is indicated with the • symbol.</p

Proportion of observations per time of day spent active fitted with a line function using the activity package in R [33] to determine proportion of time spent active.

<p>Vertical lines indicate sunrise and sunset at approximately 05.30 and 17.50 year-round.</p

Parameter estimates for <i>S</i>. <i>blouchi</i> included in the REM.

<p>Parameter estimates for <i>S</i>. <i>blouchi</i> included in the REM.</p

Camera trapping sampling precision for <i>S</i>. <i>blouchi</i>.

<p>Sampling precision was expressed as CV of <i>S</i>. <i>blouchi</i> camera trap rate with cumulative sampling effort (number of camera trap days) in the protected areas.</p