Scent-marking Behavior Research Articles

Genetic Isolation of Hypothalamic Neurons that Regulate Context-Specific Male Social Behavior.

Nearly all animals engage in a complex assortment of social behaviors that are essential for the survival of the species. In mammals, these behaviors are regulated by sub-nuclei within the hypothalamus, but the specific cell types within these nuclei responsible for coordinating behavior in distinct contexts are only beginning to be resolved. Here, we identify a population of neurons in the ventral premammillary nucleus of the hypothalamus (PMV) that are strongly activated in male intruder mice in response to a larger resident male but that are not responsive to females. Using a combination of molecular and genetic approaches, we demonstrate that these PMV neurons regulate intruder-specific male social behavior and social novelty recognition in a manner dependent on synaptic release of the excitatory neurotransmitter glutamate. These data provide direct evidence for a unique population of neurons that regulate social behaviors in specific contexts.

Scent marking in shelter dogs: Effects of sex and age

Development of scent-marking behavior from the neonatal period to early adulthood has been well studied in dogs, but there is a distinct lack of information for older dogs. I studied scent-marking behavior during single walks of 500 male and female dogs at two shelters (Tompkins County SPCA and Cortland Community SPCA). My sample included juveniles, adults, and seniors. I found a significant effect of age on frequency of urination (P<0.0001 at both shelters): seniors urinated more frequently than adults (contrast significant at the Cortland shelter; P<0.07 at the Tompkins shelter), which urinated more frequently than juveniles. Age also influenced likelihood of directing urinations at targets in the environment (P<0.0001 at both shelters): seniors directed more of their urinations than did adults (significant at Cortland shelter only), which directed more of their urinations than did juveniles. I found that males urinated more frequently than females (P<0.0001 at both shelters) and directed more of their urinations (P<0.0001 at both shelters). Significant age and sex differences did not characterize defecation at either shelter. Ground scratching, whether after urination or defecation, was rarely performed by juveniles (% that ground scratched at least once: Tompkins shelter, <14%; Cortland shelter, 0%), so I excluded juveniles from analyses of this behavior. Ground scratching after urination was not associated with sex or age (adults versus seniors) at either shelter, but was positively associated with number of directed urinations (Tompkins shelter, P<0.0001; Cortland shelter, P<0.002). Ground scratching after defecation was not associated with sex at either shelter, but was associated with age at the Tompkins shelter (P<0.03; % that ground scratched after at least one defecation: 28% of adults; 42% of seniors); a similar pattern occurred at the Cortland shelter (29% of adults; 50% of seniors), but the association failed to reach statistical significance perhaps due to smaller sample sizes. Finally, at the Tompkins shelter, ground scratching after defecation was positively associated with number of urinations followed by ground scratching (P<0.0001); here, again, a similar pattern occurred at the Cortland shelter but the association failed to reach statistical significance. These data reveal new relationships between scent-marking behaviors; indicate that some marking behaviors continue to change even after a dog has reached adulthood; and highlight the differential effects of sex and age on urination, defecation, and ground scratching.

Evaluating the responses of a territorial solitary carnivore to potential mates and competitors.

Successful communication is critical to the fitness of individuals and maintenance of populations, but less is known regarding the social contexts and reactions to scent marking by other individuals in solitary carnivores, including pumas. We evaluated the responses of resident male pumas to visitation and scent marking by potential competitors (other male pumas) and potential mates (female pumas) by capturing and marking 46 pumas (Puma concolor), and documenting scent marking behaviours using motion-triggered video cameras. By comparing resident male puma visitation rates and communication behaviours in response to either male or female visitors, we found that their visitation and communication behaviours were best explained by the combination of visitation by both competitors and potential mates. Resident males returned to scent marking sites more quickly and increased their rate of flehmen response after visitation by a females, while they increased their rate of visitation and duration of visits in response to other males. Male pumas also visited less frequently in summer and autumn when female visitation rates were lower, but males created nearly twice as many scrapes during these visits. This study suggests that advertising for mates when scent marking may sometimes overshadow the importance of deterring competitors and claiming territory.

Is there a trade-off between scent marking and hunting behaviour in a stalking predator, the Eurasian lynx, Lynx lynx?

The costs of signalling are often expressed in terms of increased predation risk to the signaller; however, whether signalling predators also incur costs due to eavesdropping by prey and may attempt to reduce these costs is less well studied. In this study, we investigated whether there is a trade-off between intraspecific communication through scent marking and the risk of alerting prey in a wild population of a stalking predator, the Eurasian lynx. We followed lynx tracks in the snow and recorded scent marks and evidence of hunting behaviour along these tracks. Lynx preferred conspicuous objects for marking and increased scent marking rate when walking along linear structures, such as forest roads. This association was strongest when lynx were hunting, while there was only a weak correlation when no evidence of hunting could be detected. On tracks with evidence of hunting behaviour, lynx engaged less in scent marking. The relationship was most evident during the mating season, when lynx increased scent marking rates while they were not hunting. We further expected lynx to mark most in areas where they had recently hunted successfully, but time and distance to the last kill were not associated with scent marking rate. Our study supports the hypothesis that lynx face a trade-off between enhancing the detection probability of scent marks by conspecifics and avoiding eavesdropping by prey, and indicates that scent marking rate is influenced by several factors.

Happily ever after? Fates of translocated nuisance woodchucks in the Chicago metropolitan area

Human-wildlife conflict is increasing as urbanization expands and wildlife species adjust to living near people. Translocation is often used to manage human-wildlife conflict because it is considered to be humane, yet fates of translocated animals are largely unknown. As an urban adapter, woodchucks (Marmota monax) are a common source of human-wildlife conflict due to their burrowing, foraging, and scent-marking behavior. We examined survival and movements of 27 nuisance woodchucks captured by a nuisance wildlife operator in the Chicago metropolitan area, radiomarked with internal transmitters, and translocated to exurban release sites mimicking typical practices. We also captured and radiomarked 16 resident woodchucks from the release landscape for comparison. Translocated woodchucks moved farther than residents immediately post release with no evidence of homing and most left the release site. Annual survival did not differ between translocated and resident woodchucks. However, survival was extremely low (0.18) compared to previous estimates for woodchucks, primarily due to high predation by coyotes (Canis latrans). Translocation should be used only when other nonlethal methods are ineffective (e.g., exclusion, removing food sources, selecting unpalatable plants for gardens). When necessary, the practice of translocation could be improved by reducing predation risk for translocated animals, either by selecting release sites with low predation risk, or by using soft-release methods, such as acclimation enclosures or artificial burrows.

Lizard movement tracks: variation in path re-use behaviour is consistent with a scent-marking function.

Individual movement influences the spatial and social structuring of a population. Animals regularly use the same paths to move efficiently to familiar places, or to patrol and mark home ranges. We found that Australian sleepy lizards (Tiliqua rugosa), a monogamous species with stable pair-bonds, repeatedly used the same paths within their home ranges and investigated whether path re-use functions as a scent-marking behaviour, or whether it is influenced by site familiarity. Lizards can leave scent trails on the substrate when moving through the environment and have a well-developed vomeronasal system to detect and respond to those scents. Path re-use would allow sleepy lizards to concentrate scent marks along these well-used trails, advertising their presence. Hypotheses of mate attraction and mating competition predict that sleepy lizard males, which experience greater intra-sexual competition, mark more strongly. Consistent with those hypotheses, males re-used their paths more than females, and lizards that showed pairing behaviour with individuals of the opposite sex re-used paths more than unpaired lizards, particularly among females. Hinterland marking is most economic when home ranges are large and mobility is low, as is the case in the sleepy lizard. Consistent with this strategy, re-used paths were predominantly located in the inner 50% home range areas. Together, our detailed movement analyses suggest that path re-use is a scent marking behaviour in the sleepy lizard. We also investigated but found less support for alternative explanations of path re-use behaviour, such as site familiarity and spatial knowledge. Lizards established the same number of paths, and used them as often, whether they had occupied their home ranges for one or for more years. We discuss our findings in relation to maintenance of the monogamous mating system of this species, and the spatial and social structuring of the population.

Feasibility of using Scent-Baited Hair Traps to Monitor Carnivore Populations in Peninsular Malaysia

Non-invasive genetic sampling is increasingly being used for monitoring mammalian carnivore populations. However, environmental conditions in the tropics challenge researchers' ability to collect samples. We present the results of a preliminary study on the feasibility of using scent-baited hair traps for population monitoring of mammalian carnivores in Peninsular Malaysia. Stations were baited using either fatty acid scent or male cologne applied to hair traps. Video camera traps were also used to monitor carnivore reactions to the scent stations. We recorded 19 visits by seven carnivore species over 764 camera trap nights. Cheek-rubbing and scent-marking behaviour was recorded only for single individuals of two species: the Malayan tiger ( Panthera tigris jacksoni) and clouded leopard ( Neofelis nebulosa). This study suggests that scent-baited hair traps hold some promise for ecological issues requiring DNA analysis in Peninsular Malaysia. Additional research is needed to develop its full potential for conservation monitoring of large carnivores.

Central oxytocin regulates social familiarity and scent marking behavior that involves amicable odor signals between male mice

The effect of oxytocin on social behavior and odor communication was investigated in male C57BL/6J mice. In three-male colonies, in visible burrow systems, icv oxytocin (OT) infusion before colony formation substantially increased huddling together over the initial 8h of grouping, accompanied by decreased expression of a number of social approaches associated with conspecific aggression and defense. OT antagonist infusion had little impact on expression of social approaches but decreased time engaging in social components including huddle over the initial 8h. These results demonstrate a linkage of social familiarity to OT availability in the brain. In a scent marking paradigm central infusion of OT reduced territorial marking towards male conspecifics, and this in turn reduced the scent marking of untreated stimulus males to OT-infused subjects. Infusion of an OT antagonist into stimulus mice who were confronted with OT-infused subjects prevented the reduction/suppression of scent marking that was normally seen following exposure of social odors released from OT-injected mice. Odor of pair-housed mice also induced a suppression of territorial scent marking in odor recipients, but OT antagonist administration into pair-housed mice blocked this suppressive effect of odor cue. These results indicate that central OT modulates release as well as detection of amicable signals facilitating/maintaining familiar relationships and suppressing territorial behavior between male mice. Overall, these findings suggest that OT plays a significant role in regulating social familiarity via changing qualities of conspecific odor cues.

Scent-marking investment and motor patterns are affected by the age and sex of wild brown bears

Members of the Carnivora employ a wide range of postures and patterns to mark their scent onto objects and thereby communicate with conspecifics. Despite much anecdotal evidence on the marking behaviour of ursids, empirical evidence of scent-marking motor patterns displayed by wild populations is lacking. Analysing the time that different age and sex classes spend at scent-marking trees and the behaviours involved at different times of year could provide further insight into the function of marking. We used camera traps stationed at scent-marking trees to investigate scent-marking behaviour by wild brown bears, Ursus arctos. Through image-based data, we found evidence to support the hypothesis that time investment and scent-marking motor patterns are dictated by the age and sex of the bear. Adult males spent more time scent marking and displayed a more complex behavioural sequence of marking than adult females and juveniles. Adult male behaviour at marking trees was consistent throughout the year, indicating a continued benefit of chemical signalling outside of the breeding season. Juvenile bear behaviour at marking trees changed with age. Young dependent cubs were more likely to imitate their mother's behaviour, whereas older dependent cubs were more likely to engage in marking behaviour independently. The marking motor patterns of independent subadults were more simplistic than those of younger dependent cubs, suggesting a change in behaviour with independence. We suggest that these findings further support the hypothesis that scent-marking behaviour by brown bears functions in intrasexual competition between adult males. Cub behaviour at marking trees suggests an influence of social learning.

Vomeronasal organ lesion disrupts social odor recognition, behaviors and fitness in golden hamsters.

Most studies support the viewpoint that the vomeronasal organ has a profound effect on conspecific odor recognition, scent marking and mating behavior in the golden hamster (Mesocricetus auratus). However, the role of the vomeronasal organ in social odor recognition, social interaction and fitness is not well understood. Therefore, we conducted a series of behavioral and physiological tests to examine the referred points in golden hamster. We found that male hamsters with vomeronasal organ lesion showed no preference between a predator odor (the anal gland secretion of the Siberian weasels (Mustela sibirica) and putative female pheromone components (myristic acid and palmitic acid), but were still able to discriminate between these 2 kinds of odors. In behavioral tests of anxiety, we found that vomeronasal organ removal causes female hamsters to spend much less time in center grids and to cross fewer center grids and males to make fewer crossings between light and dark boxes than sham-operated controls. This indicates that a chronic vomeronasal organ lesion induced anxious responses in females. In aggressive behavioral tests, we found that a chronic vomeronasal organ lesion decreased agonistic behavior in female hamsters but not in males. The pup growth and litter size show no differences between the 2 groups. All together, our data suggested that vomeronasal organ ablation disrupted the olfactory recognition of social chemosignals in males, and induced anxiety-like and aggressive behavior changes in females. However, a vomeronasal organ lesion did not affect the reproductive capacity and fitness of hamsters. Our studies may have important implications concerning the role of the vomeronasal organ in golden hamsters and also in rodents.

The Role of Spatial Distribution of Faeces in Coyote Scent Marking Behaviour

Scats are important for chemical communication in many canids, however, little is known about the faecal marking behaviour in coyotes. In this study we tested if faeces have a function as visual and scent marks during the non-breeding period, analyzing the spatial characteristics of defecation places. We predicted that if faeces are used as chemical signals, these should be deposited in substrates and/or zones that enhance their detection by conspecifics as it happens in other canid species. The study was conducted in native grasslands at the NW limit of the Chihuahuan Desert. Results showed that the proportion of faeces in conspicuous zones (91.3%) was significantly higher than those on inconspicuous zones (8.7%). However, the number of faeces deposited on inconspicuous substrates (92.1%) was significantly higher than on conspicuous substrates (7.9%). Most faeces were on the ground (99.2%) and only 0.8% where raised. 35% of faeces were deposited in crossroads, being these strategic zones repeatedly marked by the coyotes. We observed a significant negative correlation between the number of faeces in crossroads and the distance of faeces to the centre of the crossroad. A high number of scats were found in the proximity of livestock carcasses (21%). In addition, a selection of certain road sections (track and lateral) was observed. Our results suggest that the scats have an important function as scent-marks in coyotes, using specific defecation patterns that appear to correspond to the habitat characteristics in the study area.

PERFORMANCE OF ENERGY BALANCED TERRITORIAL PREDATOR SCENT MARKING ALGORITHM BASED ON LEACH PROTOCOL

Sensor node is a node in wireless sensor network (WSN) that is capable of sensing information, processing and communicating with each other node in the network. As the energy available in the sensor nodes is limited. So while designing WSN, the main concentration has to be taken part in network life time by using the energy efficient sensor node placement in many network applications. So energy efficient operation is very important, as the sensor nodes are depends on battery for operation to be carry out. It is difficult or replaces charge battery, for this sensor nodes function and operation in WSN should become energy efficient. To overcome this problem new biologically inspired technique has been introduce the algorithm and called as Energy balancing Territorial Predator Scent Marking Algorithm using LEACH protocol in WSN.TPSMA is used for sensor node schemes in terms of coverage ratio, network life time by this network efficient network can be achieved. This is based on the scent marking behavior, predator will scent mark the area due to certain factors such as resources. Sensor node will identify it’s monitored location based on their marked territories that imitate the scent matching behavior in TPSMA. The performance of the proposed technique improved and compare with other Swarm Intelligence technique. At the end of this paper we highlighted the future work of this paper.

Scent-marking behaviour and social dynamics in a wild population of Eurasian lynx Lynx lynx

Scent-marking is widespread among mammals and has been observed in many felid species. Although the behaviour is well-described, little is known about its function in wild felid populations. We investigated patterns of scent-marking and its role in intra- and intersexual communication among resident and non-resident Eurasian lynx Lynx lynx by observing interactions among wild lynx at natural marking sites by means of infrared camera traps. Marking activity of resident animals showed a peak during the mating season and was lowest during the time when females gave birth and lactated. Both sexes scent-marked, but male lynx visited marking sites much more often than females and marked relatively more often when visiting a site. Most visits to marking sites were by residents but we also observed scent-marking by non-residents. Juveniles were never observed marking. We found no evidence of lynx regularly renewing scent-marks after a certain ‘expiry date’ but the presence of a strange scent-mark triggered over-marking. Males responded similarly to the presence of another individual's scent-mark, irrespective of whether it was the top- or the underlying scent-mark in a mixture of scent-marks they encountered. Our results suggest that marking sites could serve as ‘chemical bulletin boards’, where male lynx advertise their presence and gain information on ownership relationships in a given area. Females placed their urine marks on top of the ones left by resident males, but further studies are needed to explain the functions of over-marking in females.

Discrimination of sex and reproductive state in koalas, Phascolarctos cinereus, using chemical cues in urine

Although marsupials have well-developed olfactory systems and complex scent-marking behaviours, relatively little is known about the actual function of chemical signals in this group of mammals compared to eutherian species. In this study I investigated whether koalas are able to assess the sex and reproductive state of signallers using chemical cues present in urine. Male urine induced more chemosensory investigation by males and oestrous females than female urine, and nonoestrous female koalas displayed an aversion to male urine. When presented with oestrous versus nonoestrous female urine, males but not females displayed a significant investigatory preference for oestrous urine. Taken together these results indicate that koala urine contains chemical cues permitting the discrimination of sex and female oestrous stage. These findings also add to a growing body of literature showing that chemical cues serve to advertise female reproductive state in mammals, and the first clear evidence of this in a marsupial.

Puma communication behaviours: understanding functional use and variation among sex and age classes

Intraspecific communication for mate selection sometimes varies between sexes based on different evolutionary life history patterns. Solitary felids use communication for territorial defence and location of mates, for which they use scent-marking behaviours including scraping, urine spraying, body rubbing, caterwauling, cheek rubbing, and the flehmen response, but these behaviours are not well understood in pumas (Puma concolor). We used motion-triggered video cameras to document the use of communication behaviours by male and female pumas, and used a series of experimental treatments to determine the mechanisms and importance of visual and olfactory cues in puma scrapes. We found that pumas use the physical scrape to locate communications, and then use urine to convey and interpret the communication itself. We also found significant differences among puma age and sex classes in the proportion of use and duration of time behaviours were displayed. Mature males spent significantly longer durations () on producing behaviours (scraping, body rubbing, and caterwauling behaviours) than mature females (), and males used scraping (78.5%) and body rubbing (12.4%) behaviours at a higher proportion of visits than females (13.6 and 2.7%, respectively). Mature females spent significantly longer durations () on consuming behaviours (investigating and flehmen response behaviours) than mature males (), and females used flehmen response (30.6%) and caterwauling (9.3%) behaviours at a higher proportion of visits than mature males (6.5% flehmen and 0.4% caterwauling). Male reproductive strategy appears based on advertisement for possible mates, while female reproductive strategy appears based on assessment of possible mates. The use of communication behaviours also appears to develop with age, as immature pumas rarely visited and acted as non-participants in communication behaviours.

Love is in the air: sociality and pair bondedness influence sifaka reproductive signalling

Social complexity, often estimated by group size, is seen as driving the complexity of vocal signals, but its relation to olfactory signals, which arguably arose to function in nonsocial realms, remains underappreciated. That olfactory signals also may mediate within-group interaction, vary with social complexity and promote social cohesion underscores a potentially crucial link with sociality. To examine that link, we integrated chemical and behavioural analyses to ask whether olfactory signals facilitate reproductive coordination in a strepsirrhine primate, the Coquerel's sifaka, Propithecus coquereli . Belonging to a clade comprising primarily solitary, nocturnal species, the diurnal, group-living sifaka represents an interesting test case. Convergent with diurnal, group-living lemurids, sifakas expressed chemically rich scent signals, consistent with the social complexity hypothesis for communication. These signals minimally encoded the sex of the signaller and varied with female reproductive state. Likewise, sex and female fertility were reflected in within-group scent investigation, scent marking and overmarking. We further asked whether, within breeding pairs, the stability or quality of the pair's bond influences the composition of glandular signals and patterns of investigatory or scent-marking behaviour. Indeed, reproductively successful pairs tended to show greater similarity in their scent signals than did reproductively unsuccessful pairs, potentially through chemical convergence. Moreover, scent marking was temporally coordinated within breeding pairs and was influenced by past reproductive success. That olfactory signalling reflects social bondedness or reproductive history lends support to recent suggestions that the quality of relationships may be a more valuable proxy than group size for estimating social complexity. We suggest that olfactory signalling in sifakas is more complex than previously recognized and, as in other socially integrated species, can be a crucial mechanism for promoting group cohesion and maintaining social bonds. Thus, the evolution of sociality may well be reflected in the complexity of olfactory signalling. • Sifakas have a complex scent-signalling repertoire that coordinates reproduction. • Two families of diurnal, group-living lemurs converge on complex glandular signalling. • The quality of sifaka social bonds influences scent composition and deposition. • Olfactory signalling mediates social cohesion in group-living animals. • Sociality drives the complexity of both vocal and olfactory signals.

The effect of pair bonding in Cabrera vole’s scent marking

The Cabrera vole (Microtus cabrerae) is a rare rodent living in patchy grassy areas of the Iberian Peninsula where unpaired individuals of both sexes use scent marking primarily to increase their mate-finding likelihood. Cabrera voles establish long-term pair bonds with opposite-sex conspecifics constituting a breeding pair, which is expected to reduce the efforts in searching for a new mate. Under such circumstances, scent marking as a strategy to increase mate-finding likelihood became useless. Accordingly, we hypothesise that pair bonded Cabrera voles suppress mate-finding scent marking to reduce energetic costs and predation risk. To test this hypothesis, we compared scent-marking behaviour towards a clean substrate, in both paired and non-paired voles. No differences were found in the scent marks’ type and the amount of marks placed by voles in both conditions. We also analysed the scent-marking behaviour of both sex pair bonded voles when exposed simultaneously to a clean substrate, a substrate pre-marked by males and a substrate pre-marked by females. We found no significant differences in scent-marks (urine-marked area and number of faecal boli) across the three types of substrate types. In accordance with our prediction, these results suggest that pair bonded Cabrera voles did not use scent marking for mate finding, thus providing further support to the existence of a monogamous mating strategy. Furthermore, our results fail to support the use of scent marking for territorial defence purposes.

The Role of Scent-Marking in Patchy and Highly Fragmented Populations of the Cabrera Vole (Microtus cabreraeThomas, 1906)

Rodent scent-marking is often used for territorial defence and self-advertisement, and both functions often entail the continuous scent-marking of a large area with high costs. In species with highly-fragmented populations and low density, in which the likelihood of social encounters is low, the costs of continuous scent-marking might exceed the associated fitness benefits; therefore, less intensive scent-marking only to signal presence to the opposite sex may be used. This hypothesis was tested in captivity with the Cabrera vole, a species with highly fragmented and low-density populations. Firstly, to assess the unknown scent-marking behaviour of the Cabrera voles, we conducted an assay wherein voles could scent-mark a clean substrate. Both sexes marked with urine and faeces, but never with anogenital secretions, and the amount of scent-marks was not different between sexes. In the subsequent assay, voles of each sex were given the choice of scent-mark on clean substrates or on substrates previously scent-marked by males or females. Both sexes marked with urine a larger area on substrates pre-marked by the opposite sex than on substrates pre-marked by the same-sex and clean substrates; however, no differences were found in the frequency of fecal boli deposited on the three types of substrate, and no anogenital secretions were found. The clear preference of receivers to scent-mark with urine the substrate pre-marked by the opposite sex strongly suggests that Cabrera voles use urine scent-marking for inter-sexual communication, probably to increase mate-finding likelihood, rather than for territorial defense and/or self-advertisement.

Nasopalatine Ducts and Flehmen Behavior in the Mandrill: Reevaluating Olfactory Communication in Old World Primates

Compared to other modes of communication, chemical signaling between conspecifics generally has been overlooked in Old World primates, despite the presence in this group of secretory glands and scent-marking behavior, as well as the confirmed production and perception of olfactory signals. In other mammalian species, flehmen is a behavior thought to transport primarily nonvolatile, aqueous-soluble odorants via specialized ducts to the vomeronasal organ (VNO). By contrast, Old World primates are traditionally thought to lack a functional VNO, relying instead on the main olfactory system to process volatile odorants from their environment. Here, in the mandrill (Mandrillus sphinx), we document unusual morphological and behavioral traits that typically are associated with the uptake of conspecific chemical cues for processing by an accessory olfactory system. Notably, we confirmed that both sexes possess open nasopalatine ducts and, in response to the presentation of conspecific odorants, we found that both sexes showed stereotyped behavior consistent with the flehmen response. If, as in other species, flehmen in the mandrill serves to mediate social or reproductive information, we expected its occurrence to vary with characteristics of either the signaler or receiver. Flehmen, particularly in a given male, occurred most often in response to odorants derived from male, as opposed to female, conspecifics. Moreover, odorants derived during the breeding season elicited more flehmen responses than did odorants collected during the birthing season. Lastly, odorants from reproductively cycling females also elicited more responses than did odorants from contracepted females. Although confirming a link between the nasopalatine ducts, flehmen behavior, and olfactory processing in mandrills would require further study, our observations provide new information to suggest anatomical variability within Old World primates, calling further attention to the underappreciated role of chemical communication in this lineage.

No trespassing: using a biofence to manipulate wolf movements

Context Conserving large carnivores can be challenging because of conflicts with human land use and competition with humans for resources. Predation on domestic stock can have negative economic impacts particularly for owners of small herds, and tools for minimising carnivore depredation of livestock are needed. Canids use scent marking to establish territories and avoid intraspecific conflict. Exploiting scent-marking behaviour may provide a means for manipulating canid movements. Aims We hypothesised that human-deployed scent marks (i.e. ‘biofence’) could be used to manipulate the movements of grey wolves (Canis lupus) in Idaho, USA. Methods We deployed 65 km of biofence within three wolf-pack territories during summer 2010 and 2011 and used location data from satellite-collared wolves and sign surveys to assess the effectiveness of biofencing. Key results Location data provided by satellite-collared wolves and sign surveys in 2010 showed little to no trespass of the biofence, even though the excluded areas were used by the packs in previous summers. We also opportunistically deployed a biofence in between a rendezvous site of a resident pack and a nearby sheep grazing allotment; the pack was not implicated in any depredations in summer 2010, even though they had killed sheep every year since 2006. Location data provided by satellite-collared wolves in summer 2011 showed that wolves did trespass biofences. Conclusions Biofencing effectively manipulated the movements of wolves in the first year of our study, but not the second. Implications Our work suggests that biofencing may be most limited by the apparent necessity to maintain a continuous presence once the biofence is established. The inherent labour and costs associated with such efforts may limit the usefulness of biofencing. Our work can be improved on through further testing that maintains biofencing over a longer timeframe (&gt;3 months), samples several animals per treatment pack, and uses a treatment and control design.