Scent Marking Research Articles

Temporal dynamics of scent mark composition in field‐experimental lizard populations

Abstract Animal signals are dynamic traits that can undergo considerable spatial and temporal changes and that are influenced by factors such as age, health condition and interactions with both the abiotic and biotic environment. However, much of our understanding of signal changes throughout an individual's lifetime stems from cross‐sectional, often laboratory‐based, studies focused on visual and auditory signals. Longitudinal field investigations of temporal variation in chemical signals, especially in vertebrates, remain rare despite chemical communication being the most ubiquitous form of information exchange in the natural world. To remedy this, we conducted a unique, replicated field experiment to study the temporal signal dynamics in free‐living lizard populations on natural islands. Specifically, we collected scent marks from individually marked lizards across five populations during the spring of two consecutive years and analysed the lipophilic chemical composition of these scent marks. Our findings demonstrate that the overall scent mark composition of individual lizards changed over time, shifting consistently in both direction and magnitude from year to year among individuals and across replicate populations. Similar patterns were observed for the chemical richness and diversity of scent marks. Temporal variation in the relative proportions of three potentially socially relevant signalling compounds in lizard scent marks revealed a more complex pattern: α‐tocopherol remained stable over time, oleic acid decreased and the change in octadecanoic acid proportion was body size‐dependent. Together, our results provide novel insights into how individual vertebrate chemical signals may fluctuate across space and time. We discuss the potential causes of the observed temporal variability and its consequences for chemical signal evolution. Read the free Plain Language Summary for this article on the Journal blog.

Female pumas exhibit behavioral plasticity through partitioning temporal activity at communication hubs based on life stage

AbstractIntraspecific communication among carnivores can be complex and risky, and many solitary carnivores (including pumas; Puma concolor) primarily communicate with potential mates and competitors indirectly via scent marking at communication hubs. We used multiple temporal analyses to understand if pumas of three classes (males, solo females, and females traveling with dependent kittens) varied in their temporal use of communication hubs to reduce risk while gathering information. We hypothesized that males would visit scrapes at typical times (nighttime), but that female behavioral strategies might vary based on whether they had dependent kittens or not. We found that pumas of different classes varied in their temporal patterns: male pumas concentrated their temporal activity at night (which is typical for pumas), solo females also tended to visit during the nighttime (although slightly earlier on average than males), while females with kittens were more active in the daytime. Our findings highlight the importance of communication hubs for intersexual communication in pumas and the flexibility that is inherent in puma behavioral ecology. Females adjusted their temporal behavior and visitation based on their reproductive status and life history stage, likely to assess dominant territorial males while also limiting their risk. Our study provides a mechanistic view of how communication through scent marking allows both long‐term and spatially separated communication to occur and that may allow pumas at different life stages with different risk tolerances to communicate with each other.

Heat-altered scent marks of males of a fossorial reptile still allow recognition by females but lose information on male quality

The efficacy of sexual signals in communication is often maximized under specific environmental conditions. Anthropic alterations of these conditions might, thus, negatively affect communication during reproductive behavior. In fossorial animals, inhabiting visually restricted environments, chemical senses are very important. We examined whether climatic episodes of heat-waves with unusual high temperatures may affect the information provided to females by the sexual chemical signals of males of a fossorial reptile, the amphisbaenian Blanus cinereus. The results showed that experimentally heat-altered substrate scent marks of males can still provide information to females about the presence of a male. Females spent more time on males’ scent marks, irrespective of the temperature treatment, than on control clean ones. However, heat-altered scent marks did not seem to convey information about the health state (immune response) of the producer. Females spent more time on unaltered scent marks of healthier males (probably indicating mating preferences for these males), while female preferences for some heat-altered scent marks were not related to size or immune response of the same individual males. Chemical analyses indicated that the overall chemical profile of precloacal secretions (used for scent marking) did not change with increased temperatures. However, the relationship between proportions of some compounds in secretions and males’ immune response found in unaltered secretions was lost in heat-altered ones. We conclude that unusual increased environmental temperatures may decrease the efficacy of underground sexual chemical signals in this amphisbaenian (i.e., a loss of information on male quality), and consequently, may negatively affect sexual selection and reproduction.

Characterizing the metabolome and microbiome at giant panda scent marking sites during the mating season

Scent marking sites served as a primary means of chemical communication for giant pandas, enabling intraspecific communication. We integrated metabolomics and high-throughput sequencing techniques to examine the non-targeted metabolome and microbial community structure of scent marking sites and feces in the field. Integrative analysis revealed a more comprehensive array of chemical compounds compared to previous investigations, including ketones, acids, heterocycles, alcohols, and aldehydes. Notably, specific compounds such as 2-decenal, (E)-, octanal, decanal, L-α-terpineol, vanillin, and nonanal emerged as potential key players in scent signaling. Intriguingly, our study of the microbial domain identified dominant bacterial species from the Actinobacteria, Bacteroidetes, and Proteobacteria phyla, likely orchestrating metabolic processes at scent marking sites. Comparative analyses showed, for the first time, that feces do not share the same functions as scent markers, indicating distinct functional roles. This research deepens scientific understanding of chemical communication in wild pandas.

Analysis of Legal Protection of Non-traditional Trademarks from a Global PerspectiveTaking Scent Trademarks as an Example

With the constant advancement of the economy and technology, especially the development of high-tech technology, the traditional trademark can no longer meet the needs of social and enterprise development. From traditional visual trademarks to three-dimensional trademarks, sound marks, and even scent marks, non-traditional trademarks are playing an increasingly important role in transactions. Therefore, the legal protection of non-traditional trademarks is particularly important. By collecting and reading the relevant references and materials, this paper adopts the methods of literature analysis, comparison method, and case analysis to analyze of Legal protection of non-traditional trademarks from a global perspectivetaking scent trademarks as an example. The paper points out the current situation in the protection of non-traditional trademarks, taking scent marks as an example, and puts forward some feasible suggestions, such as: Reference the "staff " representation method, Promoting scientific and technological progress, and Scent branding prompts in the product. It can be concluded that the registration and protection systems of scent trademarks in various countries are not perfect, they can be shown in the strict requirements for registrable trademarks regarding the representation of odor, the distinctiveness of trademark registration, and the functional of marks. Countries should pay more attention to them. The study suggests that it is necessary to improve the scent trademark legislation, which is conducive to better protection of intellectual property rights, encourage innovation of enterprises, and safeguard the interests of enterprises.

Sprayed Urine Emits a Pungent Odor due to its Increased Adhesion to Vertical Objects via Urinary Proteins Rather Than to Changes in its Volatile Chemical Profile in Domestic Cats.

Spraying urine on vertical objects by raising the tail is a commonly observed functional behavior for chemical communication in Felidae species, including domestic cats (Felis silvestris catus). The sprayed urine is recognized as a chemical signal for territorial ownership of their habitats. Previous studies reported that sprayed urine emits a more pungent odor than urine excreted from a squatting position. However, little is known about how sprayed urine acts as a strong scent mark in the environment. Here, we showed that sprayed urine originates only from bladder urine without any secretions, such as anal sac secretions, but it can effectively emit volatile organic compounds (VOCs) when smeared on vertical objects due to its strong adhesion. Chemical profiles of VOCs and odor qualities were similar between fresh sprayed urine and bladder urine sampled immediately after spraying from the same individuals. Meanwhile, feline-specific proteinuria arising from excretion of a carboxylesterase that produces a precursor of cat-specific odorants resulted in reduced surface tension of the urine and increased adhesion to vertical surfaces, which kept sprayed urine on the surfaces and led to the emission of large amounts of VOCs. In conclusion, proteinuria contributes to the emission of a strong odor through its enhanced adhesion to vertical objects without other secretions containing malodorous substances. These findings improve our understanding of the mechanism of scent marking via the spraying of urine for chemical communication in cats.

Size matters: Natural experiments suggest the dear enemy effect is moderated by pack size in African wild dogs.

Remote monitoring of communal marking sites, or latrines, provides a unique opportunity to observe undisturbed scent marking behaviour of African wild dogs (Lycaon pictus). We used remote camera trap observations in a natural experiment to test behavioural scent mark responses to rivals (either familiar neighbours or unfamiliar strangers), to determine whether wild dogs exhibit the "dear enemy" or "nasty neighbour" response. Given that larger groups of wild dogs represent a greater threat to smaller groups, including for established residents, we predicted that the overarching categories "dear enemy" vs. "nasty neighbour" may be confounded by varying social statuses that exists between individual dyads interacting. Using the number of overmarks as a metric, results revealed an interaction between sender and receiver group size irrespective of familiarity consistent with this prediction: in general, individuals from large resident packs overmarked large groups more than they overmarked smaller groups, whereas individuals from smaller packs avoided overmarking larger groups, possibly to avoid detection. Monitoring a natural system highlights variables such as pack size that may be either overlooked or controlled during scent presentation experiments, influencing our ability to gain insights into the factors determining territorial responses to rivals.

Treat Yourself: Pilot Testing a New Method to Treat Mange in Wild Carnivores.

Mange is a skin disease caused by mites that parasitize an animal's skin, often yielding inflamed immune responses and hair loss. At a population level, mange may reduce survival and cause population declines. Many forms of mange can be treated quite effectively when an animal is in hand; however, this is not often feasible for many free-ranging wildlife populations. Some animals, particularly territorial carnivores, will rub or roll to scent mark and transmit information about their presence to other individuals. We posited that rub stations comprised, in part, of anthelmintic medication and foreign scents that induce rubbing could be used to remotely treat mange in the wild. We deployed 39 rub stations containing lure and dye in Santa Monica Mountains National Recreation Area, Southern California, USA, October-November 2022. Carnivores rubbed or rolled at >97% of rub stations, with coyotes (Canis latrans), gray foxes (Urocyon cinereoargenteus), and bobcats (Lynx rufus) being the most abundant species. Time to first rub or roll was generally <1 wk. Several sympatric species (e.g., mule deer, Odocoileus hemionus) were detected at rub stations but did not rub. Our pilot test provides strong evidence that treating mange in wild carnivores may be possible using the remote medicinal rub stations we describe. Future efforts to add medicine to rub stations and monitor for a change in mange prevalence are a logical next step.

Blind date: female fossorial amphisbaenians prefer scent marks of large and healthy males.

Selecting a good mate is a decision with important fitness consequences. For this reason, mate choice has promoted the evolution of sexual ornaments signaling the quality of an individual. In fossorial animals, inhabiting visually restricted underground environments, chemical senses should be very important for mate choice. We examined whether sexual chemical signals (substrate scent marks) produced by males of the Iberian worm lizard, Blanus cinereus, a strictly fossorial blind amphisbaenian, provide information to females on morphological traits and health state. We administered corticosterone (CORT) to males simulating a continuous stressor affecting their health. Females preferred settling at sites scent-marked by males in comparison with similar sites with female scent or unmarked sites, but the attractiveness of males' scent differed between individuals. Females preferred scent marks of larger/older males and with a higher immune response, while their body condition and CORT treatment were unrelated to female preferences. Chemical analyses showed that proportions of some compounds in precloacal secretions of males (used to produce scent marks) were correlated with the morphological (body size) and health state (immune response and body condition, but not CORT treatment) of these males. These results suggest that females may make site-selection decisions based on assessing the chemical characteristics of males' scent marks, which were reliably related to some of the traits of the male that produced the scent. Therefore, females might use chemical senses to increase the opportunities to find and mate with males of high quality, coping with the restrictions of the subterranean environment.

Latrine site selection by African clawless otters, Aonyx capensis, and their behavior during latrine visitations.

Latrine sites are used as areas for the deposition of scent-containing excretions and play important roles in intraspecific olfactory communication, territoriality, sexual attraction, and defense behaviors of many mammals. African clawless otters (Aonyx capensis) likely use latrine sites as primary areas for scent marking and scent communication but no studies to date have investigated their potential role or site selection. We assessed latrine site selection at 2 spatial scales (micro- and macroscale) and recorded behaviors via camera trap recordings. Thirty-eight latrine sites were identified and assessed at 2 locations in Mtunzini on the north coast of KwaZulu-Natal, South Africa (uMlalazi Nature Reserve and Zini Fish Farm) during the months of August to November 2021. Latrine sites were identified through several intensive surveys, while we characterized nonselected sites through a systematic sampling approach. Latrine and control sites were inventoried along a 52-m buffer around all water bodies in both study areas. At each site we measured a series of potential environmental predictors, including horizontal and vertical vegetation cover, surface slope, and averaged wind speeds for days classified as relatively wind-still and relatively windy. To assess the relative role of various environmental predictors, we used a binomial generalized linear model resource selection function to model both spatial scales of latrine site selection. The majority of latrine sites were located at the ecotone between 2 vegetation units or between a vegetation unit and a water source. At a macroscale, latrine sites were associated with areas containing little vegetative substrate cover and minimal canopy cover. The top-ranked models at the microscale also indicated that latrine sites were characterized as occurring in open areas with less canopy and horizontal cover and on flatter areas that are relatively protected against wind. The most common behaviors recorded at 3 latrine sites were the "jiggle dance" (42%) and sniffing (29%). We hypothesize that otters evaluate numerous environmental parameters to enhance the functionality of latrine sites. For example, sites with little vegetative cover may increase the conspicuousness of latrines to conspecifics, while areas exposed to less wind likely aid in the retention of scent. Ongoing research is characterizing the behaviors of otters around latrines and chemical signatures of latrine sites in an effort to facilitate interpretation of their social function to African clawless otters.

Patterns of scent marking by African wild dogs, Lycaon pictus, at shared marking sites

Patterns of scent marking by African wild dogs, Lycaon pictus, at shared marking sites

Nonlocal Mechanistic Models in Ecology: Numerical Methods and Parameter Inferences

Animals utilize their surroundings to make decisions on how to navigate and establish their territories. Some species gather information about competing groups by observing them from a distance, detecting scent markings, or relying on memories of encounters with rival populations. Gathering such information involves a nonlocal process, prompting the development of mechanistic models that incorporate nonlocal terms to explore species movement. These models, however, pose analytical and computational challenges. In this study, we focus on a multi-species advection–diffusion model that incorporates nonlocal advection. To efficiently compute solutions for this system involving a large number of interacting species, we introduce a numerical scheme using spectral methods. Additionally, we examine the influence of various parameters and interaction potentials on population densities. Our investigation aims to provide a method to identify the primary factors driving species movements, and we validate our approach using synthetic data.

Methanethiol: A Scent Mark of Dysregulated Sulfur Metabolism in Cancer.

In order to cope with increased demands for energy and metabolites as well as to enhance stress resilience, tumor cells develop various metabolic adaptations, representing a hallmark of cancer. In this regard, the dysregulation of sulfur metabolism that may result in elevated levels of volatile sulfur compounds (VSCs) in body fluids, breath, and/or excretions of cancer patients has recently gained attention. Besides hydrogen sulfide (H2S), methanethiol is the predominant cancer-associated VSC and has been proposed as a promising biomarker for non-invasive cancer diagnosis. Gut bacteria are the major exogenous source of exposure to this foul-smelling toxic gas, with methanethiol-producing strains such as Fusobacterium nucleatum highly abundant in the gut microbiome of colorectal carcinoma (CRC) patients. Physiologically, methanethiol becomes rapidly degraded through the methanethiol oxidase (MTO) activity of selenium-binding protein 1 (SELENBP1). However, SELENBP1, which is considered a tumor suppressor, is often downregulated in tumor tissues, and this has been epidemiologically linked to poor clinical outcomes. In addition to impaired removal, an increase in methanethiol levels may derive from non-enzymatic reactions, such as a Maillard reaction between glucose and methionine, two metabolites enriched in cancer cells. High methionine concentrations in cancer cells may also result in enzymatic methanethiol production in mitochondria. Moreover, enzymatic endogenous methanethiol production may occur through methyltransferase-like protein 7B (METTL7B), which is present at elevated levels in some cancers, including CRC and hepatocellular carcinoma (HCC). In conclusion, methanethiol contributes to the scent of cancer as part of the cancer-associated signature combination of volatile organic compounds (VOCs) that are increasingly being exploited for non-invasive early cancer diagnosis.

Do pied tamarins increase scent-marking in response to urban noise?

Sounds produced by human activities are often loud and may mask acoustic signals used by other species for communication. To circumvent this, some animals use various strategies, including shifting modality completely or complementing acoustic information by using additional modalities to communicate. Here we used pied tamarins (Saguinus bicolor) as models to explore whether shifts in communication modalities occur under increased anthropogenic noise or deploy them complementarily. We predicted that in circumstances where noise could impede acoustic communication the study animals would exhibit more scent-marking behaviour (i.e. olfactory communication) while reducing the emission of long calls (i.e. acoustic communication). We collected information on vocal and scent-marking behaviour in nine groups of wild pied tamarins in urban forests in Manaus, Amazonian Brazil. We found that scent marking occurrence increased with noise amplitude, though long call numbers did not change. Thus, our results do not suggest a complete shift between channels but complementation of information, where scent marking may compensate for the impacts of anthropogenic noise on the acoustic channel. This is an interesting result from a conservation perspective as pied tamarins may be capable of coping with city noise to communicate with conspecifics, a key tenet of species survival.

Signal detection theory applied to giant pandas: Do pandas go out of their way to make sure their scent marks are found?

Inter-animal communication allows signals released by an animal to be perceived by others. Scent-marking is the primary mode of such communication in giant pandas (Ailuropoda melanoleuca). Signal detection theory propounds that animals choose the substrate and location of their scent marks so that the signals released are transmitted more widely and last longer. We believe that pandas trade-off scent-marking because they are an energetically marginal species and it is costly to generate and mark chemical signals. Existing studies only indicate where pandas mark more frequently, but their selection preferences remain unknown. This study investigates whether the marking behavior of pandas is consistent with signal detection theory. Feces count, reflecting habitat use intensity, was combined with mark count to determine the selection preference for marking. The results showed that pandas preferred to mark ridges with animal trails and that most marked tree species were locally dominant. In addition, marked plots and species were selected for lower energy consumption and a higher chance of being detected. Over 90% of the marks used were the longest-surviving anogenital gland secretion marks, and over 80% of the marks were oriented toward animal trails. Our research demonstrates that pandas go out of their way to make sure their marks are found. This study not only sheds light on the mechanisms of scent-marking by pandas but also guides us toward more precise conservation of the panda habitat.

Female rats communicate through scent marks.

Female rats communicate through scent marks.

Comportement De Territorialité De Propithecus Deckenii Dans Les Aires Protégées Complexe Tsimembo Manambolomaty Et Mandrozo

This study aims to understand the behavior territoriality of the lemur Decken's Sifaka Propithecus deckenii in the Protected Areas (PAs) Complexe Tsimembo Manambolomaty and Mandrozo in the central-west of Madagascar between November 2017 and April 2018, and between July and October 2018. The continuous focal animal sampling method was used to monitor eight groups of Sifakas, two groups of the intact habitat and two groups from the disturbed habitat in each PA. Scent marking frequencies per focal groups differs between the two habitats types and is influenced by sex in favor of males. Season does not impacted this activity. The home range (define by MCP and 95% Kernel density estimate) and core area varies between monitored groups and the daily path length can reach 234 ± 98 m to 362 ± 110 m. These parameters are not influenced by season and habitat types. However, the intensity of territory use does not have any variation among the studied groups. The mean average « defensibility index » value for P. deckenii is 1.74 ± 0.70 (n = 8). The studied species has ability to adjust their territorial behavior, despite the degradation of habitat in sustainable use zones

Identifying social behaviours related to disease transmission in banded mongoose from accelerometer data

Abstract Current methods for identifying and predicting infectious disease dynamics in wildlife populations are limited. Pathogen transmission dynamics can be complex, influenced by behavioural interactions between and among hosts, pathogens and their environments. These behaviours may also be influenced directly by observers, with observational research methods being limited to habituated species. Banded mongoose Mungos mungo are social, medium size carnivores infected with the novel tuberculosis pathogen Mycobacterium mungi. This pathogen is principally transmitted during normal olfactory communication behaviours. Banded mongoose behavioural responses to humans change over the landscape, limiting the use of direct observational approaches in areas where mongoose are threatened and flee. The accelerometers in bio‐logging devices have been used previously to identify distinct behaviours in wildlife species, providing a tool to quantifying specific behaviours in ecological studies. We deployed Axy‐5X model accelerometers (TechnoSmArt) on captive mongoose to determine whether accelerometers could be used to identify key mongoose behavioural activities previously associated with M. mungi transmission. After two collaring periods, we determined that three distinct behavioural activities could be identified in the accelerometer data: bipedal vertical vigilance, running and scent marking activity; behaviours that have been shown to vary across land type in the banded mongoose. Results from this work advance current data analytics and provide modifications to data analysis works flows, updating and expanding upon current methodologies. We also provide preliminary evidence of successful mathematical classification of the target behaviours, supporting the future use of these devices. Methods applied here may allow model estimates of M. mungi transmission in free‐ranging mongoose to be refined with possible application to other systems where direct observation approaches have limited application.

Nest-associated scent marks help bumblebees localizing their nest in visually ambiguous situations.

Social insects such as ants and bees are excellent navigators. To manage their daily routines bumblebees, as an example, must learn multiple locations in their environment, like flower patches and their nest. While navigating from one location to another, they mainly rely on vision. Although the environment in which bumblebees live, be it a meadow or a garden, is visually stable overall, it may be prone to changes such as moving shadows or the displacement of an object in the scenery. Therefore, bees might not solely rely on visual cues, but use additional sources of information, forming a multimodal guidance system to ensure their return home to their nest. Here we show that the home-finding behavior of bumblebees, when confronted with a visually ambiguous scenario, is strongly influenced by natural scent marks they deposit at the inconspicuous nest hole when leaving their nest. Bumblebees search for a longer time and target their search with precision at potential nest locations that are visually familiar, if also marked with their natural scent. This finding sheds light on the crucial role of odor in helping bees find their way back to their inconspicuous nest.

Unraveling female communication through scent marks in the Norway rat

Chemical communication by females remains poorly understood, with most attention focused on female advertisement of sexual receptivity to males or mother-offspring communication. However, in social species, scents are likely to be important for mediating competition and cooperation between females determining individual reproductive success. Here, we explore chemical signaling by female laboratory rats (Rattus norvegicus) to test i) whether females target their deployment of scent information differentially according to their sexual receptivity and the genetic identity of both female and male conspecifics signaling in the local environment and ii) whether females are attracted to gain the same or different information from female scents compared to males. Consistent with targeting of scent information to colony members of similar genetic background, female rats increased scent marking in response to scents from females of the same strain. Females also suppressed scent marking in response to male scent from a genetically foreign strain while sexually receptive. Proteomic analysis of female scent deposits revealed a complex protein profile, contributed from several sources but dominated by clitoral gland secretion. In particular, female scent marks contained a series of clitoral-derived hydrolases and proteolytically truncated major urinary proteins (MUPs). Manipulated blends of clitoral secretion and urine from estrus females were strongly attractive to both sexes, while voided urine alone stimulated no interest. Our study reveals that information about female receptive status is shared between females as well as with males, while clitoral secretions containing a complex set of truncated MUPs and other proteins play a key role in female communication.