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Asian elephant (Elephas maximus) and African savanna elephant (Loxodonta africana) populations collectively managed by ex‐situ facilities accredited by the Association of Zoos and Aquariums (AZA) face sustainability challenges. Among the priorities to strengthen animal wellbeing and population sustainability is male elephant management. We conducted a survey of AZA facilities currently housing male elephants to assess the status, challenges, and priorities in three areas of male elephant management: musth, socialization, and semen collection. Surveys were administered to elephant care teams at AZA‐accredited institutions between November 2022 and February 2023, and we received responses from 34 institutions (91.9% of AZA‐accredited facilities holding adult male elephants), housing 32 adult male Asians and 26 adult male Africans. Most facilities prioritized breeding and male socialization over musth management and semen collection (although most facilities acknowledged that all these efforts are important), citing leadership support and staffing as most important to achieve male management goals. Behaviors most commonly accompanying musth included reduced appetite, difficulty training or shifting, human‐directed aggression, and interest in females. Musth timing was variable between males and facilities. Most males were well‐socialized with females and/or other males, though elephant compatibility and facility design were limiting factors in managing socialization. Although 60.6% of facilities collected semen or were training for semen collection, very few male elephants could reliably provide viable semen samples, challenging assisted reproductive efforts that could bolster population sustainability in both species. Together, our results provide a better understanding of the state of male elephant management, offering specific areas deserving of research and development to enhance wellbeing and sustainability. Research Highlights: We surveyed 34 AZA institutions to measure status, priorities, and challenges of major components of male elephant management (musth, socialization, and semen collection).Musth management and socialization practices widely varied between institutions, and additional research is needed to characterize implications of this variation for wellbeing and sustainability.Further capacity building is needed to enhance semen collection efforts at the population level. [ABSTRACT FROM AUTHOR]

Introduction: Monitoring overnight behavior is important in assessing the overall wellbeing of ex-situ elephant populations, with recumbent rest and stereotypy as key indicators of welfare. However, there have been few studies that address the overnight behavior of singly housed male elephants with a history of stereotypy. We conducted an opportunistic case study of the overnight behavior (i.e., rest and stereotypy) of a singly housed geriatric male Asian elephant at the Oklahoma City Zoo to identify his overnight behavioral rhythms in response to physiological (musth) and environmental changes (habitat access, automatic timed feeders) and guide management strategies. Methods: Infrared cameras were utilized to conduct continuous focal-animal sampling of the elephant's behavior between 20:00 and 08:00 in indoor and outdoor habitats. Sampling occurred from January 2023 to October 2023, with a total of 179 overnight observations. Results: The elephant exhibited recumbent rest for 175.66 ± 6.80 (mean ± SE) minutes per night and was engaged in stereotypy for 175.88 ± 9.68 minutes per night. While there was no significant relationship between stereotypy and the sexual state of musth, musth was associated with reduced durations of recumbent rest. Access to both indoor and outdoor habitats was significantly related to decreased stereotypy compared to indoor-only treatments. Recumbent rest occurred most frequently between 02:00 and 05:00, and stereotypic behavior was most common between 06:00 and 08:00. Contrary to our expectations, automatic feeders did not significantly reduce stereotypy. Discussion: The results of this study provide insight into the behavioral patterns of a geriatric male Asian elephant, demonstrating the importance of implementing an animal-centered approach to enhance animal wellbeing. As the zoo-housed Asian elephant population grows and continues to age, this case study emphasizes the importance of developing comprehensive welfare strategies for the elephants in our care. [ABSTRACT FROM AUTHOR]

Simple Summary: African elephants commonly enter farmlands across their ranges and trample or consume crops, creating conflicts with farmers and challenges for conservation priorities. Farmers may retaliate and injure elephants, but the extent to which this occurs is relatively unknown. However, scars found on elephants may be evidence of past negative interactions. The objective of our study was to describe the presence of scars in an elephant population in the Greater Tsavo Ecosystem, a region of high human–elephant conflict in Kenya. We monitored and catalogued a population in the Kasigau Wildlife Corridor from 2017 to 2021, noting the number of scars and their placement on individuals. Presumably, evidence of conflict between elephants is more likely to be found on the head or rump areas of elephants, whereas humans are most likely to injure the body of elephants. We found that adult males were much more likely to have scars than adult females, older males were more likely to have scars than younger males, and more scars were located on the body as opposed to the rump and head. Understanding how many elephants in a population have scars and the location of scars can describe the potential level of human–elephant conflict in a population. This valuable information can be used to better understand the level of conflict in a community and aid in management recommendations. Human–elephant conflict (HEC) compromises crop security and threatens elephant conservation. Most commonly, HEC manifests as crop-foraging as elephants modify natural foraging strategies to incorporate crops. Farmers may retaliate by frightening or harming elephants, leaving scars from inflicted wounds. We assessed the prevalence and distribution of scars on the bodies of African savanna elephants (Loxodonta africana) observed in the Kasigau Wildlife Corridor (KWC), part of the Greater Tsavo Ecosystem of Kenya, where conflict is prevalent. We surmised that scars on the body are largely a result of HEC as opposed to scars on the rump or head, which we attributed primarily to elephant–elephant conflict. We hypothesized that: (1) male elephants would have more scars than females; (2) older males would be more likely to have scars than younger males; and (3) most scars would be located on the bodies of elephants. We assessed scars from a photographic catalogue of elephants from the KWC. In line with our hypotheses, male elephants were more likely to have scars than females (32% of males compared to 6% of females); older males had significantly more scars than younger males (61% compared to 24%); and the majority of scars (89%) were located on the body. Scar presence may be useful as an animal-centered indicator to estimate the prevalence and demographic patterns of HEC. [ABSTRACT FROM AUTHOR]

The sustainability of endangered Asian elephants in human care is threatened in part by low breeding success and concerns over individual animal wellbeing. Male elephants have received less research attention compared to females, yet males deserve special consideration due to their unique reproductive biology (particularly the sexual state of "musth") and the complex interaction of physiological, environmental, and social pressures they face. We measured fecal androgen metabolites (FAMs), fecal glucocorticoid metabolites (FGMs), and fecal triiodothyronine metabolites (FT3s) collected weekly over approximately 12 months from 26 male Asian elephants housed in zoos across the US, hypothesizing that FAM, FGM, and FT3 concentrations would be associated with temporal correlates of musth and would vary further with intrinsic (musth status, age, body condition) and extrinsic (social environment) factors. The duration of each musth episode was positively associated with exposure to male conspecifics and negatively associated with body condition. Further, elevated FAM concentrations were associated with social exposure, age, and body condition, and FGM concentrations also varied with age and body condition. FT3 concentrations were not associated with any factor we measured. We also identified periods of lower FAM concentration than confirmed musth episodes (but still higher than baseline FAM concentrations) that we termed "elevated FAM episodes." The durations of these episodes were negatively correlated with exposure to other male elephants. Together, these results provide evidence that hormone profiles (including those that are predicted to change around musth) vary significantly between male Asian elephants in a way that may be attributed to intrinsic and extrinsic factors. Studies like these serve to enhance the sustainability of ex-situ populations by providing wildlife managers with information to enhance the health, welfare, and reproduction of threatened species like Asian elephants. [ABSTRACT FROM AUTHOR]

Simple Summary: The conservation of wild and zoo-housed Asian elephants partly depends on developing our understanding of male elephant social behavior. Once thought to be solitary, we now know that male elephants can display rich social exchanges with both males and females. However, these interactions are expected to change with age and around the sexually active state of "musth." We used behavioral data from wild and zoo-housed elephant populations to investigate how age, musth, and environmental factors influence how male elephants socialize and associate with group members. In Sri Lanka, only male elephants of older age (>20 years) exhibited signs of musth, but even some of the youngest zoo-housed elephants underwent musth (as young as 11 years). Additionally, we found that age and musth status predicted whether a wild male elephant associated with females, other males or was alone, as well as the number of conspecifics (males and females) in the same group with which a male was observed. Finally, rates of aggression, prosocial behavior (affiliative behaviors that promote positive social bonds between elephants), and submissive behavior exhibited by wild and zoo-housed male elephants were associated with age, musth status, the number of elephants presented, and group type (all-male or mixed sex). These results provide motivation for future studies of social behavior in male Asian elephants, as they will contribute to the reproduction and conservation of this endangered species. Asian elephants are endangered, and the long-term viability of the species depends on integrative approaches to address the sustainability of in-situ and ex-situ populations. Growing evidence shows that male elephants exhibit extensive and flexible social behavior that rivals the complexity of that of females. Male elephant sociality is expected to change dramatically around the unique sexual state of musth. However, data related to male Asian elephant sociality is lacking. Here, we conducted complementary observations in Wasgamuwa National Park, Sri Lanka, and North American zoos of male Asian elephant social behavior. Age and musth status, along with other factors, were associated with variation in social behavior and group formation of males. In wild male elephants, both musth status and age impacted elephant associations within all-male and mixed-sex groups: non-musth elephants were generally sighted less often in mixed-sex groups as they aged, while the inverse occurred with musth elephants. Musth status interacted with age to predict the number of conspecifics with which a wild male elephant associated: younger males were observed with more females during non-musth (but the opposite was true during musth), and male elephants between 20 and 30 years were observed with the highest number of male conspecifics except during musth. Finally, we found variation in aggression, prosocial behavior, and submissive behavior was influenced by intrinsic (age and musth status) and extrinsic factors (group size and type) in similar ways in both populations; prosocial behavior was most common and was influenced by the number of conspecifics present (both populations), and age, group type, and musth status (zoo population), while aggression was rare, especially among older elephants. We suggest that longitudinal studies of this threatened species will be particularly helpful to promote the reproduction and conservation of Asian elephants in in-situ and ex-situ environments. [ABSTRACT FROM AUTHOR]

Sexual selection mediated by multimodal signals is common among polygynous species, including seasonally breeding mammals. Indirect benefit models provide plausible explanations for how and why mate selection can occur in the absence of direct benefits. Musth — an asynchronous reproductive state in male elephants — facilitates both inter- and intrasexual selection via indirect benefits, and it is further communicated through a multimodal signal. In this review, we synthesise existing evidence that supports the hypothesis that musth is a multimodal signal subject to sexual selection and that male elephants increase their direct fitness by propagating this signal while females accrue indirect benefits. Musth is characterised by a suite of physiological and behavioural changes, serving to facilitate copulation between the sexes, and via multisensory modalities musth conveys honest information about the condition of a male. Female elephants mate preferentially with musth males, increasing their own fitness in the absence of direct benefits. In addition, musth resolves dynamic dominance hierarchies among male elephants and often eliminates the need for costly physical combat. Future work in this field should investigate potential postcopulatory selection mechanisms in elephants, including sperm competition and cryptic female choice. These topics join other fundamental questions related to sexual selection, signalling, and indirect benefits that are still unanswered in elephants. [ABSTRACT FROM AUTHOR]

Context: Human–elephant conflict (HEC) is a major threat to Asian elephants as humans and elephants are forced to share common resources. In Sri Lanka, human-dominated landscapes adjacent to protected areas promote high rates of HEC, especially in the form of crop-foraging by elephants. Crop-foraging can be dangerous to both elephants and humans involved in the conflict. Gunfire is a common way for human communities to deter crop-foraging elephants, and gunshot wounds are commonly described in this elephant population on necropsy. Aims: We sought to quantify and describe unique scar patterns among Asian elephants in a protected area, Wasgamuwa National Park, attributed to HEC. Methods: We identified 38 adult female and 64 adult male elephants and recorded the age class and body condition of each with established standards. Using photographs, we counted the number, position, and relative size of all scars on each animal. Key results: Male elephants had significantly more scars than did females, and for males, the number of scars increased progressively with age. Additionally, male elephants with higher body conditions had more scars. Finally, males tended to have more scars towards the head, especially at older ages. Conclusions: Differences in total scar counts between the sexes in this population imply that male elephants in this area more frequently engage in HEC than do females, following observations previously described in the literature. Furthermore, the fact that male elephants acquired progressively more scars as they aged, and that fatter elephants had more scars, indicates that previous exposure to HEC may not have been a deterrent for future events among these males, and potentially, crops served as valuable food sources for these animals. Finally, the changing body locations of these scars with age in males possibly shows plastic behavioural responses during crop-foraging or lower tolerance by farmers towards habitual crop foragers. Implications: These results emphasise the need for animal-based approaches to HEC mitigation. Similarly, conservation managers in Sri Lanka and other elephant range countries should investigate similar methods that estimate patterns of HEC to develop effective management strategies directly targeting animals most likely to engage in conflict. Human–elephant conflict (HEC) threatens the long-term survival of Asian elephants. The present study described unique scars incurred by elephants during HEC incidents adjacent to a protected area in Sri Lanka, and we described differences in scar patterns on the basis of age, sex, and body condition. These results illustrated the need for adaptive conservation strategies to address HEC in Sri Lanka and elsewhere, and these scar patterns may be useful for monitoring HEC in this elephant population. Photograph by Chase LaDue. [ABSTRACT FROM AUTHOR]

Population‐level analyses suggest that habitat complexity, but not necessarily space availability, has important welfare outcomes for elephants in human care. At the Dallas Zoo, the opening of a new exhibit complex allowed us to measure the behavior of two female African elephants across three treatments to evaluate the independent effects of complexity and space. Preoccupancy observations were conducted in the elephants' older exhibit, which consisted of a smaller, more simple yard (630 m2). Subsequent postoccupancy observations measured behavior in two different spaces in the new exhibit: a larger, complex yard (15,000 m2), and a smaller, but complex yard (1,520 m2). The elephants' overall activity levels were greater in complex habitats, regardless of their size. Similar effects of habitat complexity oversize were observed with greater rates of foraging and lower rates of being stationary. Furthermore, elephants were out of view of visitors significantly more in the small, simple yard compared to either of the more complex habitats. However, exhibit size affected the incidence of stereotypic behavior (with lower rates of stereotypy in the larger exhibit compared to the smaller yards) and investigatory behavior (elephants investigated their environments more with increasing size and complexity). Behavioral diversity also increased with exhibit size and complexity. These results indicate that space availability alone is not sufficient to enhance the behavioral welfare of zoo elephants. Therefore, facilities with limited space can still encourage species‐appropriate behaviors and improved welfare for the elephants in their care by converting a small, simple area into a more complex habitat. HIGHLIGHTS: Overall activity and behavioral diversity of African elephants increased with exhibit size and complexity. These results are important for zoos with limited space and/or those that are considering renovating or replacing their elephant exhibits. [ABSTRACT FROM AUTHOR]

Abstract: The physical structure of a signal is not sufficient to determine its meaning. For chemical signals between conspecifics, this concept is termed “pheromonal parsimony.” The function of a compound depends not only on its molecular structure but also on its context, which can include signal concentration and various receiver attributes. We sought to investigate the contextual flexibility of chemosensory responses through bioassays with Asian elephant (Elephas maximus) sex pheromones of various concentrations (frontalin, from males, and (Z)‐7‐dodecenyl acetate [Z7‐12:Ac], from females). We hypothesized that elephants would respond stronger to higher concentrations, especially towards the opposite‐sex pheromone, and that receiver age and sexual experience would modify responses. We examined responses of 73 captive elephants to both compounds. Pheromone concentration impacted the rate of chemosensory response, which was further modified by the sex, age and/or sexual experience of the receiver. Response rates increased with concentration for each compound across both sexes. Experience shaped male responses with older, physiologically primed males responding more often. The interaction between experience and age affected female response to frontalin, but not to Z7‐12:Ac. Furthermore, response thresholds were modified by sexual experience in most cases: experienced animals generally had lower thresholds than inexperienced animals. Elephants responded to each solution according to its perceived relevance, including concentration. These results also indicate that receiver attributes (e.g., sex, age and sexual experience) may modify seemingly fixed chemosensory responses and further emphasize the flexibility of vertebrate communication systems. [ABSTRACT FROM AUTHOR]

Background: Radio and satellite telemetry collars have been used across taxa, including with elephants, in situ for decades to collect data used for various analyses. To quantify the movement patterns of African elephants, Loxodonta africana, in a zoo, we modified a Real-Time Location System using active Radio Frequency Identification tags originally developed for inventory and asset tracking in warehouses. This is the first phase of a multi-phase project that we have termed the Real-Time Observer of Animal Movement. It allows for the continuous data collection and data analytics of elephant movement and space use in a mixed-species African savanna habitat at the Dallas Zoo. This system could prove to be a useful remote welfare tool for a variety of animal species at multiple facilities. Results: We determined that a Real-Time Location System using Radio Frequency Identification tags could be used to continuously monitor elephant movement, social relationships, and exhibit use remotely over several acres in a zoo with a volume of data not otherwise possible to achieve. Real-time visual outputs include current location in the habitat, paths taken around the habitat, habitat preferences, social relationships between the elephants, and data tables with average rate of travel and distance traveled. Conclusions: The pilot system at the Dallas Zoo is the first-ever use of active Radio Frequency Identification technology to observe zoo animal behavior patterns and monitor welfare. It has proven to be an effective tool for efficiently collecting data continuously and remotely throughout the day and night. It represents the first phase of a multifaceted project that will add capabilities and functionality for additional species and other zoos to form a network for sharing data to inform captive animal management strategies. [ABSTRACT FROM AUTHOR]

Complementary studies of wild and zoo-housed animals offer insight into behavioral variation across a range of conditions including the context under which various behaviors evolved in natural settings. This information can be used to improve the sustainability of in-situ and ex-situ populations and enhance the well-being of individuals. Managed ex-situ populations are critical to the long-term existence of Asian elephants, yet relatively little is known about male reproductive behavior compared to females. Male elephants undergo a unique sexual state called "musth" that further complicates in-situ and ex-situ management strategies. The ability to manage musth males to enhance breeding success and overall wellness of elephants is dependent upon better understanding how intrinsic and extrinsic factors influence male behavioral variation around musth. Here, we observed 62 free-ranging male Asian elephants in Sri Lanka and compared their behavior to observations from 26 elephants managed in facilities around the US. We hypothesized that musth is associated with significant behavioral changes that can be used to define distinct stages in the progression of musth. During observations, we quantified environmental variables and recorded musth status of each focal elephant using visual indicators (temporal gland secretions and urine dribbling). We showed that musth's behavioral correlates (including changes in locomotion, foraging, alertness, and chemosensory behavior) were remarkably similar in wild and zoo-housed elephants. We also found that behavioral variation around musth was also associated with intrinsic (e.g., musth stage, age) and extrinsic factors (e.g., space availability, temperature) in zoo-housed, but not wild, elephants, indicating that musth is potentially plastic in changing environments. As musth progressed, we noted distinct behavioral signatures that define four stages of sexual activity in male elephants: non-musth, early musth, full musth, and post-musth. Finally, although we did not observe significant changes in overall social behavior (including aggression) during musth, we found that elephants increased the frequency with which they displayed certain behaviors associated with communication (e.g., alertness, chemosensory behavior, ear-flapping) in both populations. Together, these results indicate the significant behavioral changes that occur during musth in wild and zoo-housed elephants, and that musth progresses in distinct behavioral stages that can be easily distinguished by visual indicators. Studies like these serve to provide wildlife managers with information about a species' unique, evolved behavioral strategies and how these seemingly fixed behaviors may be influenced by intrinsic and extrinsic factors in predictable ways. • We analyzed the behavior of wild and zoo-housed male Asian elephants around musth. • Behavioral changes around musth were similar between wild and zoo-housed elephants. • Behavioral variation was affected by musth stage, age, and extrinsic factors. • We propose four behavioral stages of male elephant sexual activity: non-musth, early musth, full musth, and post-musth. [ABSTRACT FROM AUTHOR]

Human–wildlife conflict (HWC) is becoming increasingly prevalent as human activity expands, and monitoring the impact of habitat quality on wildlife mortality related to HWC is critical for the well-being of wildlife and people. Using ten years of necropsies from free-ranging Asian elephants in the Northwestern Wildlife Region (NWR) of Sri Lanka, we quantified the effect of habitat quality on human–elephant conflict (HEC) (i.e., human-caused elephant mortality), hypothesizing that both artificial (e.g., forest cover loss) and natural (e.g., water availability, temperature) changes would be associated with elephant mortality. We collated necropsies from 348 elephants that died due to human activity from 2009 to 2018, comparing the results with data on forest cover loss, perennial water, rainfall, temperature, and human population sizes. Over the study period, we found that forest cover loss was significantly correlated with human-caused mortality in a district-specific manner. Similarly, access to perennial water and precipitation levels appeared to influence mortality, but not temperature, human population density, or percent land cover used for agriculture. We conducted emerging hot spot analyses to identify areas within the NWR that should be prioritized for protection, which included landscapes that are not currently protected (approximately 43% of the hot spots we identified). Similarly, areas that we identified as cold spots included many areas with minimal forest cover loss. Together, our results emphasize the impact that human activity can have on the measurable outcomes of HEC. We suggest that adaptive HWC management strategies that use retrospective analyses should inform any potential changes to the protection of vital wildlife habitats, such as the north central dry zone of Sri Lanka. [ABSTRACT FROM AUTHOR]

Simple Summary: Among all taxa, messages transmitted via chemical signals are the oldest and most universal. For Asian and African elephants, odors convey information between individuals, and between elephants and their environment. Pheromones are chemical signals used within a species and while thousands of pheromones have been identified for insects, only a few dozen have been elucidated in mammals and other vertebrates. Amazingly, two pheromones are known for Asian elephants: one signals receptivity in females and the other a heightened reproductive state in males. The elephant trunk serves numerous functions including detecting airborne odors and transporting chemicals in substrates such as urine to be detected by multiple sensory systems. Obvious trunk behaviors provide clear means to assess the interest of elephants in scent sources. Thus, elephants can serve as a model system for investigating chemical signaling. Prior to the 21st century, research on elephant chemical signaling focused on within species communication. In the 21st century, these studies expanded with increasing fieldwork. Studies also revealed the use of odors to detect threats and forage for food. Chemical signaling in elephants remains a bouquet for further exploration with promising applications for the conservation of wild elephants and the management of elephants in human care. Chemical signals are the oldest and most ubiquitous means of mediating intra- and interspecific interactions. The three extant species of elephants, the Asian elephant and the two African species, savanna and forest share sociobiological patterns in which chemical signals play a vital role. Elephants emit secretions and excretions and display behaviors that reveal the importance of odors in their interactions. In this review, we begin with a brief introduction of research in elephant chemical ecology leading up to the 21st century, and then we summarize the body of work that has built upon it and occurred in the last c. 20 years. The 21st century has expanded our understanding on elephant chemical ecology, revealing their use of odors to detect potential threats and make dietary choices. Furthermore, complementary in situ and ex situ studies have allowed the careful observations of captive elephants to be extended to fieldwork involving their wild counterparts. While important advances have been made in the 21st century, further work should investigate the roles of chemical signaling in elephants and how these signals interact with other sensory modalities. All three elephant species are threatened with extinction, and we suggest that chemical ecology can be applied for targeted conservation efforts. [ABSTRACT FROM AUTHOR]

• We exposed 50 elephants to sexual pheromones and recorded behavioral responses. • Behavioral diversity was dependent upon receiver attributes and social access. • Changes in behavior were noted, including foraging, locomotion, and stereotypy. • Results suggest that targeted pheromones may be enriching for elephants. The use of odors is a popular form of sensory enrichment, yet few studies have investigated the longer lasting effects of biologically relevant chemical signals like pheromones. Asian elephants (Elephas maximus) are unique because they are commonly held in zoos and utilize two single-compounds to synchronize reproduction: frontalin (a pheromone produced by male elephants in musth) and (Z)-7-dodecenyl acetate (Z 7-12:Ac, a pheromone produced by female elephants around ovulation). While Asian elephant chemical signaling dynamics have been well-studied, no reports exist on the broader behavioral effects (i.e., primer effects) of either of these pheromones. The purpose of this study was to describe the primer effects of both frontalin and Z 7-12:Ac for potential enrichment applications. We bioassayed 50 elephants at 10 zoos using synthetic versions of these two pheromones that replicated the concentrations at which they are produced naturally. We found that behavioral diversity in response to these pheromones was influenced both by the degree of exposure to the chemicals and by properties of the receiver, such as sex, sexual experience, age, and social access, with models that included all or most of these factors explaining much of the variation in the bioassay data for frontalin (R 2 (c) = 0.42) and Z 7-12:Ac (R 2 (c) = 0.59). Furthermore, both males and females exhibited distinct changes in activity levels in the presence of frontalin or Z 7-12:Ac, with specific behavioral differences noted. For instance, frontalin stimulated increased activity (and decreased inactivity) among female elephants (P < 0.001). Foraging (P = 0.029) and walking (P = 0.001) increased when males were exposed to frontalin, but it also stimulated increased time spent engaged in stationary stereotypy (P < 0.001). On the other hand, Z 7-12:Ac encouraged greater activity levels in female (P < 0.001) and male (P = 0.010) elephants. These results support the use of pheromones as enrichment opportunities for elephants, and suggest appropriate chemical signals should be considered for other species. Because these compounds hold biological, ecological, and/or evolutionary salience, they can have long-lasting effects and are particularly relevant to long-term management strategies. In conjunction with other forms of sensory enrichment—including biologically novel odors—pheromones have the potential to enhance the wellness of zoo-housed species. [ABSTRACT FROM AUTHOR]

Despite the ubiquity of odours in mammals, few studies have documented the natural olfactory abilities of many 'non-model' species such as the Asian elephant. As Asian elephants are endangered, we may apply odours to more effectively manage threatened populations. We implemented a habituation-discrimination paradigm for the first time in Asian elephants to test the ability of elephants to discriminate between unfamiliar male elephant urine, hypothesizing that elephants would successfully distinguish non-musth from musth urine and also distinguish identity between two closely related individuals. We conducted two bioassay series, exposing three female and three male zoo-housed elephants to the same urine sample (non-musth urine in the first series, and urine from an unfamiliar individual in the second) over 5 days. On the sixth day, we simultaneously presented each elephant with a novel sample (either musth urine or urine from a second unfamiliar individual) alongside the habituated urine sample, comparing rates of chemosensory response to each sample to indicate discrimination. All elephants successfully discriminated non-musth from musth urine, and also urine from two unfamiliar half-brothers. Our results further demonstrate the remarkable olfactory abilities of elephants with promising implications for conservation and management.