Supporting conservationists' mental health through better working conditions.

Biodiversity conservation work can be challenging but rewarding, and both aspects have potential consequences for conservationists' mental health. Yet, little is known about patterns of mental health among conservationists and its associated workplace protective and risk factors. A better understanding might help improve working conditions, supporting conservationists' job satisfaction, productivity, and engagement, while reducing costs from staff turnover, absenteeism, and presenteeism. We surveyed 2311 conservation professionals working in 122 countries through an internet survey shared via mailing lists, social media, and other channels. We asked them about experiences of psychological distress, working conditions, and personal characteristics. Over half were from and worked in Europe and North America, and most had a university-level education, were in desk-based academic and practitioner roles, and responded in English. Heavy workload, job demands, and organizational instability were linked to higher distress, but job stability and satisfaction with one's contributions to conservation were associated with lower distress. Respondents with low dispositional and conservation-specific optimism, poor physical health, and limited social support, women, and early-career professionals were most at risk of distress in our sample. Our results flag important risk factors that employers could consider, although further research is needed among groups underrepresented in our sample. Drawing on evidence-based occupational health interventions, we suggest measures that could promote better working conditions and thus may improve conservationists' mental health and abilities to protect nature.

Mejores condiciones de trabajo para apoyar la salud mental de los conservacionistas Resumen La conservación de la biodiversidad puede ser difícil pero gratificante y ambos aspectos pueden tener consecuencias en la salud mental de los conservacionistas. Sin embargo, sabemos poco sobre la salud mental de los conservacionistas, sus patrones y los factores de protección y riesgo asociados al lugar de trabajo. Un mayor conocimiento ayudaría a mejorar las condiciones de trabajo, pues impulsaría la satisfacción laboral, la productividad y el compromiso de los conservacionistas, mientras se reducen los costos derivados de la rotación de personal, el ausentismo y el presentismo. Encuestamos a 2,311 profesionales de la conservación de 122 países con una encuesta virtual compartida por listas de correo, redes sociales y otros medios. Les preguntamos a los profesionales sobre sus experiencias de estrés psicológico, condiciones de trabajo y características personales. Más de la mitad trabajaban y procedían de Europa y Norteamérica; la mayoría respondió en inglés, contaba con estudios universitarios y actualmente desempeña funciones académicas y profesionales. La carga de trabajo excesiva, las exigencias laborales y la inestabilidad organizacional se relacionaron con un mayor estrés, mientras la estabilidad laboral y la satisfacción con la contribución propia a la conservación se asociaron con un menor estrés. En nuestra muestra, los encuestados con baja disposición y un optimismo específico hacia la conservación, mala salud física, apoyo social limitado, las mujeres y los profesionales que inician su carrera son los que corren un mayor riesgo de sufrir estrés. Nuestros resultados señalan importantes factores de riesgo que los empresarios podrían considerar, aunque es necesario seguir investigando entre los grupos menos representados en nuestra muestra. Con base en las intervenciones de salud laboral respaldadas con pruebas, sugerimos medidas que podrían promover mejores condiciones de trabajo y, así mejorar la salud mental de los conservacionistas y su capacidad para proteger la naturaleza.

Little Evidence to Support the Risk-Disturbance Hypothesis as an Explanation for Responses to Anthropogenic Noise by Pygmy Marmosets (Cebuella niveiventris) at a Tourism site in the Peruvian Amazon.

The risk-disturbance hypothesis states that animals react to human stressors in the same way as they do to natural predators. Given increasing human-wildlife contact, understanding whether animals perceive anthropogenic sounds as a threat is important for assessing the long-term sustainability of wildlife tourism and proposing appropriate mitigation strategies. A study of pygmy marmoset (Cebuella niveiventris) responses to human speech found marmosets fled, decreased feeding and resting, and increased alert behaviors in response to human speech. Following this study, we investigated pygmy marmoset reactions to playbacks of different acoustic stimuli: controls (no playback, white noise and cicadas), anthropogenic noise (human speech and motorboats), and avian predators. For each playback condition, we recorded the behavior of a marmoset and looked at how the behaviors changed during and after the playback relative to behaviors before. We repeated this on ten different marmoset groups, playing each condition once to each group. The results did not replicate a previous study on the same species, at the same site, demonstrating the importance of replication in primate research, particularly when results are used to inform conservation policy. The results showed increased scanning during playbacks of the cicadas and predators compared with before the playback, and an increase in resting after playbacks of avian predators, but no evidence of behavior change in response to playbacks of human speech. There was no effect of ambient sound levels or distance between the playback source and focal animals on their behavior for all playback conditions. Although we find that noise can change the behavior of pygmy marmosets, we did not find evidence to support the risk-disturbance hypothesis. Supplementary Information: The online version contains supplementary material available at 10.1007/s10764-022-00297-9.

The medium over the message: Differential knowledge of conservation outreach activities and implications for threatened species.

Conservation outreach is regularly conducted to increase support for conservation by altering local awareness and attitudes about species or environmental issues. However, there is often little assessment of the effectiveness of these activities. We investigated knowledge of past conservation outreach in 26 villages adjacent to Bawangling National Nature Reserve, Hainan, China, which contains the last population of the Hainan gibbon (Nomascus hainanus). The medium of past outreach activities was reported most frequently by interviewees, followed by who delivered them and the outreach topic, with the fewest interviewees reporting the specific messages being communicated (the consequences of following conservation management policies). Negatively-framed messages, emphasizing prohibited activities and associated punishments, were reported more than positively-framed messages that aimed to foster conservation support. Male interviewees and those with higher education levels reported more aspects of past activities. The Hainan gibbon had higher salience than other threatened native species, and reporting the occurrence (but not necessarily the content) of past outreach was associated with increased likelihood of knowing that gibbons were threatened. These findings highlight the need for conservation outreach to increase both exposure and retention of key messages among target audiences. Meaningful and concrete conservation benefits should be communicated to local communities, and the effectiveness of outreach using a flagship species could be expanded to also improve awareness of other conservation-priority species within the same landscape.

Balancing making a difference with making a living in the conservation sector.

Goals play important roles in people's lives because they focus attention, mobilize effort, and sustain motivation. Understanding conservationists' satisfaction with goal progress may provide insights into real-world environmental trends and flag risks to their well-being and motivation. We asked 2694 conservationists working globally how satisfied they were with progress toward goals important to them. We then explored how this satisfaction varied among groups, including demographic and occupational. Finally, we looked at respondents' experiences associated with goal-progress satisfaction. Many (94.0%) indicated that making a meaningful contribution to conservation was an important goal for them, and over half were satisfied or very satisfied in this area (52.5%). However, respondents were generally dissatisfied with progress on collective conservation goals (e.g., stopping species loss). Some groups were more likely to report dissatisfaction than others. For instance, those in conservation for longer tended to be less satisfied with collective goal progress (log odds -0.21, 95% credibility interval [CI] -0.32 to -0.10), but practitioners reported greater satisfaction (log odds 0.38, 95% CI 0.15-0.60). Likewise, those who were more optimistic in life (log odds 0.24, 95% CI 0.17-0.32), male (log odds 0.25, 95% CI 0.10-0.41), and working in conservation practice (log odds 0.25, 95% CI 0.08-0.43) reported greater satisfaction with individual goal progress. Free-text responses suggested widespread dissatisfaction with livelihood goals, particularly related to job security and adequate compensation. Although contributing to conservation appeared to be a source of satisfaction, slow goal progress in other areas--particularly around making a living--looked to be a source of distress and demotivation. Employers, funders, professional societies, and others should consider ways to help those in the sector make a difference while making a satisfactory living by, for example, prioritizing conservationists' well-being when allocating funding. This support could include avoiding exploitative practices, fostering supportive work environments, and celebrating positive outcomes.

El Balance entre Hacer una Diferencia y Ganarse la Vida en el Sector de la Conservación 21-323 Resumen Los objetivos juegan un papel importante en la vida de las personas porque enfocan la atención, movilizan esfuerzos y mantienen la motivación. El entendimiento de la satisfacción de los conservacionistas con el progreso de sus objetivos podría proporcionar información sobre las tendencias ambientales del mundo real y marcar los riesgos para su bienestar y motivaciones. Les preguntamos a 2694 conservacionistas trabajando alrededor del mundo cuán satisfechos están con el progreso hacia los objetivos que consideran más importantes. Después exploramos cómo esta satisfacción varió entre grupos, incluyendo grupos demográficos y laborales. Finalmente, observamos las experiencias de los respondientes asociadas con la satisfacción con el progreso de los objetivos. Muchos (94%) indicaron que contribuir significativamente a la conservación es un objetivo importante para ellos, y más de la mitad estuvieron satisfechos o muy satisfechos en este campo (52.5%). Sin embargo, los respondientes también mostraron una inconformidad generalizada con el progreso de los objetivos colectivos de conservación (p. ej.: detener la pérdida de especies). Algunos grupos tuvieron una mayor probabilidad de reportar inconformidades que otros grupos. Por ejemplo, aquellos con mayor tiempo en la conservación tendieron a estar menos satisfechos con el progreso de los objetivos colectivos (probabilidad log -0.21, 95% intervalo de credibilidad [IC] -0.32 a -0.10), pero los practicantes reportaron una mayor satisfacción (probabilidad log 0.38, 95% IC 0.15-0.60). De igual manera, quienes cuentan con mayor optimismo cotidiano (probabilidad log 0.24, 95% IC 0.17-0.32), son de sexo masculino (probabilidad log 0.25, 95% IC 0.10-0.41) y trabajan en la práctica de la conservación (probabilidad log 0.25, 95% IC 0.08-0.43) reportaron una mayor satisfacción con el progreso de los objetivos individuales. Las respuestas de texto libre sugirieron una inconformidad generalizada con los objetivos de sustento, particularmente los relacionados con la seguridad laboral y las compensaciones adecuadas. Aunque contribuir a la conservación parece ser una fuente de satisfacción, el progreso lento de los objetivos en otras áreas - particularmente las relacionadas con ganarse la vida - indicaba ser una fuente de angustia y desmotivación. Los empleadores, financiadores, las sociedades profesionales y demás deberían considerar maneras para ayudar a aquellos en el sector de la conservación a lograr una diferencia a la vez que se ganan la vida satisfactoriamente, por ejemplo, mediante la priorización del bienestar de los conservacionistas al momento de asignar financiamientos. Este apoyo podría incluir evitar prácticas explotadoras, fomentar ambientes de trabajo solidarios y celebrar los resultados positivos.

Corrigendum: A Severe Lack of Evidence Limits Effective Conservation of the World's Primates.

[This corrects the article DOI: 10.1093/biosci/biaa082.].

The bean method as a tool to measure sensitive behavior.

Conservationists need to measure human behavior to guide decisions and evaluate their impact. However, activities can be misreported and reporting accuracy may change following conservation interventions, making it hard to verify any apparent changes. Techniques for asking sensitive questions are increasingly integrated into survey designs to improve data quality, but some can be costly or hard for nonexperts to implement. We demonstrate a straightforward, low-cost approach, the bean method in which respondents give anonymous answers by adding a colored bean to a jar to denote a yes or no response. We applied the bean method to measure wild-meat hunting and trading over 2 years at a conservation-project (hunting reduction) site in Gola Forest, Liberia. We extended the technique to accommodate questions about hunting and meat-selling frequency. We compared responses given using the bean method and direct questioning for groups that did and did not participate in conservation interventions. Results from the bean method corresponded to those from direct questioning, and there was no indication of change in question sensitivity following conservation interventions. Estimates from both methods indicated that wild-meat trading decreased in project and nonproject households (from 36% to 20%) and that hunting decreased in 1 project group (38-28%). Where inconsistent answers were given (2-6% of respondents), differences were in both directions and were most likely attributable to measurement error. The bean method was quick and straightforward to administer in a low-literacy setting. We showed how it can be modified for answers of more than 2 categories and consider it a valuable tool that could be adapted for a wide range of conservation settings.

El Método del Frijol como Herramienta para Medir los Comportamientos Sensibles Resumen Los conservacionistas necesitan medir el comportamiento humano para dirigir las decisiones tomadas y evaluar su impacto. Sin embargo, las actividades pueden estar mal reportadas y la fiabilidad de los reportes puede cambiar después de implementadas las intervenciones de conservación, lo cual complica la verificación de cualquier cambio aparente. Las técnicas para realizar preguntas sensibles cada vez se integran más al diseño de los censos y así mejorar la calidad de los datos, aunque algunas pueden ser caras o complicadas de implementar para quienes no son expertos. Demostramos una estrategia directa y de bajo costo, el método del frijol, en el cual los respondientes proporcionan respuestas anónimas al añadir un frijol pintado dentro de un frasco y así indicar una respuesta de sí o no. Aplicamos el método del frijol para medir la cacería y el mercado de carne silvestre durante dos años dentro de un proyecto de conservación (reducción de la cacería) en el bosque Gola, Liberia. Extendimos la técnica para acomodar preguntas sobre la frecuencia de la caza y la venta de carne. Comparamos las respuestas dadas usando el método del frijol y aquellas dadas en el cuestionamiento directo a grupos que participaban o no en las intervenciones de conservación. Los resultados obtenidos con el método del frijol correspondieron a aquellos obtenidos con los cuestionamientos directos y no hubo indicación de cambios en la sensibilidad de las preguntas después de las intervenciones de conservación. Las estimaciones de ambos métodos indicaron que el mercado de carne silvestre disminuyó en los hogares participantes o no en el proyecto (de 36% a 20%) y que la cacería disminuyó en un grupo del proyecto (38% a 28%). En donde se dieron respuestas contradictorias (2-6% de los respondientes), las diferencias fueron en ambas direcciones y en su mayoría probablemente eran atribuibles al error en la medición. El método del frijol fue rápido y directo para administrarlo en un ambiente de bajo alfabetismo. Mostramos cómo puede modificarse para respuestas con más de dos categorías y lo consideramos una herramienta valiosa que podría adaptarse para una gama amplia de escenarios de conservación.

A Severe Lack of Evidence Limits Effective Conservation of the World's Primates.

Threats to biodiversity are well documented. However, to effectively conserve species and their habitats, we need to know which conservation interventions do (or do not) work. Evidence-based conservation evaluates interventions within a scientific framework. The Conservation Evidence project has summarized thousands of studies testing conservation interventions and compiled these as synopses for various habitats and taxa. In the present article, we analyzed the interventions assessed in the primate synopsis and compared these with other taxa. We found that despite intensive efforts to study primates and the extensive threats they face, less than 1% of primate studies evaluated conservation effectiveness. The studies often lacked quantitative data, failed to undertake postimplementation monitoring of populations or individuals, or implemented several interventions at once. Furthermore, the studies were biased toward specific taxa, geographic regions, and interventions. We describe barriers for testing primate conservation interventions and propose actions to improve the conservation evidence base to protect this endangered and globally important taxon.

Human speech reduces pygmy marmoset (Cebuella pygmaea) feeding and resting at a Peruvian tourist site, with louder volumes decreasing visibility.

Although potentially beneficial in terms of raising awareness and conservation funding, tourist visitation of wild primates can have negative impacts on visited groups. Tourism-generated noise is a relatively understudied facet of ecotourism research, and the effects of tourist-generated speech on free-ranging, wild primates has never been explored previously. This study investigates the behavioral responses of 10 groups of pygmy marmosets (Cebuella pygmaea) to human speech. Through the use of an experimental playback study using recorded human speech, we show that pygmy marmosets within the Tamshiyacu-Tahuayo Reserve, Peru, are significantly less visible, and often move completely out of sight after louder playbacks. Although no consistent differences were found in other behaviors with playback duration and volume, playbacks of human speech tended to increase the amount of time individuals were alert and decrease feeding and resting behaviors. Our results demonstrate that human speech can alter the behavior of visited primates, and identifies a decrease in primate visibility within the increasing volume. As all trials in this study took place near a marmoset group's feeding tree, moving out of sight from the visible study area is a particularly energetically costly behavior, and also has a negative effect on visitor enjoyment as it limits the time that they are able to view the target species. This response was not observed (nor was any other consistent behavior change) in control trials where the marmosets were exposed to human presence but not to speech, suggesting that negative tourist impacts can be reduced by encouraging tourists to refrain from speaking in the presence of visited primate groups.

Audience segmentation to improve targeting of conservation interventions for hunters.

Audience segmentation could help improve the effectiveness of conservation interventions. Marketers use audience segmentation to define the target audience of a campaign. The technique involves subdividing a general population into groups that share similar profiles, such as sociodemographic or behavioral characteristics. Interventions are then designed to target the group or groups of interest. We explored the potential of audience segmentation for use in defining conservation target groups with a case study of hunters in Liberia. Using 2 data sets describing households (n = 476) and hunters (n = 205), we applied a clustering method in which infinite binomial mixture models group hunters and households according to livelihood and behavior variables and a simple method to define target groups based on hunting impact (hunting households and high-impact hunters). Clusters of hunters and households differed in their experiences with confiscation of catch at roadblocks and participation in livelihood-support programs, indicating that these interventions operate unevenly across subsets of the population. By contrast, the simple method masked these insights because profiles of hunting households and high-impact hunters were similar to those of the general population. Clustering results could be used to guide the development of livelihood and regulatory interventions. For example, a commonly promoted agricultural activity, cocoa farming, was practiced by only 2% (out of 87) of the largest hunter cluster of nonlocal gun hunters but was prevalent among local trappers, suggesting that assistance aimed at cocoa farmers is less appropriate for the former group. Our results support the use of audience segmentation across multiple variables to improve targeted intervention designs in conservation.

Segmentación del Público para Mejorar la Focalización de las Intervenciones de Conservación para los Cazadores Resumen La segmentación del público podría ayudar a mejorar la efectividad de las intervenciones de conservación. Los publicistas utilizan la segmentación del público para definir al público focal de una campaña. La técnica incluye la subdivisión de una población general en grupos que comparten perfiles similares, como las características socio-demográficas o de comportamiento. Después se diseñan las intervenciones para enfocarse en el grupo o los grupos de interés. Exploramos el potencial de la segmentación del público en el uso de la definición de grupos con objetivos de conservación usando el estudio de caso de los cazadores en Liberia. Con dos conjuntos de datos de descripciones de los hogares (n = 476) y de los cazadores (n = 205) aplicamos un método de agrupación en el cual los modelos de mezcla binomial infinita agruparon a los cazadores y a los hogares de acuerdo a las variables de sustento y de comportamiento. También aplicamos un método simple para definir los grupos focales con base en el impacto de la caza (hogares de cazadores y cazadores de alto impacto). Los grupos de cazadores y de hogares difirieron en experiencias con la confiscación de la caza en retenes y en participación dentro de programas de apoyo al sustento, lo que indica que estas intervenciones operan disparejamente en los subconjuntos de la población. En contraste, el método simple enmascaró estas percepciones ya que los perfiles de los hogares de cazadores y de los cazadores de alto impacto fueron similares a los de la población general. La agrupación de los resultados podría usarse para guiar el desarrollo del sustento y de las intervenciones regulatorias. Por ejemplo, el cultivo de cacao, una actividad agrícola que se promueve frecuentemente, sólo lo practicaba el 2% (de 87) del mayor grupo de cazadores de los cazadores armados no locales, pero fue prevaleciente entre los trampeadores locales, lo que sugiere que la asistencia enfocada hacia los cultivadores de cacao es menos apropiada para el primer grupo. Nuestros resultados respaldan el uso de la segmentación del público en múltiples variables para mejorar los diseños de intervenciones focalizadas en la conservación.

Imminent extinction in the wild of the world's largest amphibian.

Species with large geographic ranges are considered resilient to global decline [1]. However, human pressures on biodiversity affect increasingly large areas, in particular across Asia, where market forces drive overexploitation of species [2]. Range-wide threat assessments are often costly and thus extrapolated from non-representative local studies [3]. The Chinese giant salamander (Andrias davidianus), the world's largest amphibian, is thought to occur across much of China, but populations are harvested for farming as luxury food [4]. Between 2013 and 2016, we conducted field surveys and 2,872 interviews in possibly the largest wildlife survey conducted in China. This extensive effort revealed that populations of this once-widespread species are now critically depleted or extirpated across all surveyed areas of their range, and illegal poaching is widespread.

The impact of gold mining and agricultural concessions on the tree cover and local communities in northern Myanmar.

Myanmar offers unique opportunities for both biodiversity conservation and foreign direct investment due to projected economic growth linked to natural resource exploitation. Industrial-scale development introduces new land uses into the landscape, with unknown repercussions for local communities and biodiversity conservation. We use participatory mapping of 31 communities, focus groups in 28 communities, and analyses of forest cover change during 2000-2010 using MODIS vegetation continuous fields images, to understand the social and environmental impacts of gold mining and agricultural concessions in Myanmar's Hukaung Valley (~21,800 km2). Local communities, particularly the poorest households, benefit from work and trade opportunities offered by gold mining and agricultural companies but continue to depend on forests for house construction materials, food, and income from the sale of forest resources. However, gold mining and agricultural concessions reduce tree cover, potentially reducing access to forest resources and further marginalizing these households. Our analyses do not provide evidence that long-term resident communities contributed to forest cover loss between 2000 and 2010. We argue that landscape management, which recognizes local community rights to customary community use areas, and appropriate zoning for commercial land uses and protected areas could contribute to both local livelihoods and protect biodiversity throughout Myanmar during economic growth.

Analysis of the Capacity of Google Trends to Measure Interest in Conservation Topics and the Role of Online News.

With the continuous growth of internet usage, Google Trends has emerged as a source of information to investigate how social trends evolve over time. Knowing how the level of interest in conservation topics--approximated using Google search volume--varies over time can help support targeted conservation science communication. However, the evolution of search volume over time and the mechanisms that drive peaks in searches are poorly understood. We conducted time series analyses on Google search data from 2004 to 2013 to investigate: (i) whether interests in selected conservation topics have declined and (ii) the effect of news reporting and academic publishing on search volume. Although trends were sensitive to the term used as benchmark, we did not find that public interest towards conservation topics such as climate change, ecosystem services, deforestation, orangutan, invasive species and habitat loss was declining. We found, however, a robust downward trend for endangered species and an upward trend for ecosystem services. The quantity of news articles was related to patterns in Google search volume, whereas the number of research articles was not a good predictor but lagged behind Google search volume, indicating the role of news in the transfer of conservation science to the public.

The natural place to begin: the ethnoprimatology of the Waorani.

Ethnoprimatology is an important and growing discipline, studying the diverse relationships between humans and primates. However there is a danger that too great a focus on primates as important to humans may obscure the importance of other animal groups to local people. The Waorani of Amazonian Ecuador were described by Sponsel [Sponsel (1997) New World Primates: Ecology, evolution and behavior. New York: Aldine de Gruyter. p 143-165] as the "natural place" for ethnoprimatology, because of their close relationship to primates, including primates forming a substantial part of their diet. Therefore they are an ideal group in which to examine contemporary perceptions of primates in comparison to other types of animal. We examine how Waorani living in Yasuní National Park name and categorize primates and other common mammals. Although there is some evidence that the Waorani consider primates a unique group, the non-primate kinkajou and olingo are also included as part of the group "monkeys," and no evidence was found that primates were more important than other mammals to Waorani culture. Instead, a small number of key species, in particular the woolly monkey (Lagothrix poeppigii) and white-lipped peccary (Tayassu pecari), were found to be both important in the diet and highly culturally salient. These results have implications for both ethnoprimatologists and those working with local communities towards broader conservation goals. Firstly, researchers should ensure that they and local communities are referring to the same animals when they use broad terms such as "monkey," and secondly the results caution ethnoprimatologists against imposing western taxonomic groups on indigenous peoples, rather than allowing them to define themselves which species are important.

Hunted woolly monkeys (Lagothrix poeppigii) show threat-sensitive responses to human presence.

Responding only to individuals of a predator species which display threatening behaviour allows prey species to minimise energy expenditure and other costs of predator avoidance, such as disruption of feeding. The threat sensitivity hypothesis predicts such behaviour in prey species. If hunted animals are unable to distinguish dangerous humans from non-dangerous humans, human hunting is likely to have a greater effect on prey populations as all human encounters should lead to predator avoidance, increasing stress and creating opportunity costs for exploited populations. We test the threat sensitivity hypothesis in wild Poeppigi's woolly monkeys (Lagothrix poeppigii) in Yasuní National Park, Ecuador, by presenting human models engaging in one of three behaviours "hunting", "gathering" or "researching". These experiments were conducted at two sites with differing hunting pressures. Visibility, movement and vocalisations were recorded and results from two sites showed that groups changed their behaviours after being exposed to humans, and did so in different ways depending on the behaviour of the human model. Results at the site with higher hunting pressure were consistent with predictions based on the threat sensitivity hypothesis. Although results at the site with lower hunting pressure were not consistent with the results at the site with higher hunting pressure, groups at this site also showed differential responses to different human behaviours. These results provide evidence of threat-sensitive predator avoidance in hunted primates, which may allow them to conserve both time and energy when encountering humans which pose no threat.

Male blue monkeys alarm call in response to danger experienced by others.

Male blue monkeys (Cercopithecus mitis stuhlmanni) of Budongo Forest, Uganda, produce two acoustically distinct alarm calls: hacks to crowned eagles (Stephanoaetus coronatus) and pyows to leopards (Panthera pardus) and a range of other disturbances. In playback experiments, males responded to leopard growls exclusively with a series of pyows and to eagle shrieks predominantly with hacks. Responses to playbacks of these alarm call series matched the responses to the corresponding predators, suggesting that the calls conveyed something about the nature of the threat. When responding to a series of hacks, indicating an eagle, males responded predominately with hacks, but produced significantly more calls if their group members were close to the playback stimulus than far away, regardless of their own position. When responding to a series of pyows, indicating a range of disturbances, males responded with pyows, but call rates were independent of the distance of other group members. The results suggest that males took into account the degree of danger experienced by other group members.