Development of an automated method of detecting stereotyped feeding events in multisensor data from tagged rorqual whales

The introduction of animal‐borne, multisensor tags has opened up many opportunities for ecological research, making previously inaccessible species and behaviors observable. The advancement of tag technology and the increasingly widespread use of bio‐logging tags are leading to large volumes of sometimes extremely detailed data. With the increasing quantity and duration of tag deployments, a set of tools needs to be developed to aid in facilitating and standardizing the analysis of movement sensor data. Here, we developed an observation‐based decision tree method to detect feeding events in data from multisensor movement tags attached to fin whales (Balaenoptera physalus). Fin whales exhibit an energetically costly and kinematically complex foraging behavior called lunge feeding, an intermittent ram filtration mechanism. Using this automated system, we identified feeding lunges in 19 fin whales tagged with multisensor tags, during a total of over 100 h of continuously sampled data. Using movement sensor and hydrophone data, the automated lunge detector correctly identified an average of 92.8% of all lunges, with a false‐positive rate of 9.5%. The strong performance of our automated feeding detector demonstrates an effective, straightforward method of activity identification in animal‐borne movement tag data. Our method employs a detection algorithm that utilizes a hierarchy of simple thresholds based on knowledge of observed features of feeding behavior, a technique that is readily modifiable to fit a variety of species and behaviors. Using automated methods to detect behavioral events in tag records will significantly decrease data analysis time and aid in standardizing analysis methods, crucial objectives with the rapidly increasing quantity and variety of on‐animal tag data. Furthermore, our results have implications for next‐generation tag design, especially long‐term tags that can be outfitted with on‐board processing algorithms that automatically detect kinematic events and transmit ethograms via acoustic or satellite telemetry.     

Changes in relationships of nulliparous and parous females of Japanese monkeys at arashiyama with some aspects of troop organization

Social interactions of the adult females (nulliparous, primiparous, multiparous young, and multiparous old) of the Arashiyama-B troop of Japanese monkeys were studied. Using focal-animal and instantaneous sampling techniques, specifically identified social interactions involving allogrooming, social play, and agonism, nonspecific body-contact with and proximity to other animals were recorded from 1975 to 1978. By identifying the animals who had the above mentioned social interactions with the focal females, an attempt has been made to analyze the changes in relationships between the females of different classes and their closest kins, distant kins, and non-kins. Multiparous young females spend more time in social interactions involving allogrooming, nonspecific body-contact, and proximity than do females of the other classes and most of their social interactions are centered around their own offspring. Social interactions of the nulliparous females are fewer than those of the young mothers. But, the social interactions of the nulliparous females with their kins are much more frequent than those of the other females, i.e., once a female bears offspring, she concentrates her efforts in raising it and her social life becomes closed than before. Social interactions of the old mothers decrease and their social life is also centered more around their own young offspring. However, the social interactions of the females with non-kins, the interactions which strengthen troop integration, are independent of the class of the females. This report constitutes one part of the thesis submitted by the author to the Faculty of Science of Kyoto University in 1979 for the award of degree of Doctor of Science.     

Coevolution of Facial Expression and Social Tolerance in Macaques

The purpose of this study is to test the hypothesis that social tolerance drives the evolution of facial expression in macaques. Macaque species exhibit a range of social styles that reflect a continuum of social tolerance. Social interactions in more tolerant taxa tend to be less constrained by rank and kinship than in less‐tolerant macaques. I predicted that macaques that are more tolerant would exhibit a wider range of facial displays than less‐tolerant species because interactions that are open to negotiation are characterized by greater uncertainty than interactions that are constrained by rank or kinship. To test this hypothesis, I conducted a phylogenetically informed regression analysis (N = 11) using previously published data on repertoire size and two quantitative measures of social tolerance (conciliatory tendency and counter‐aggression). As predicted, macaques with more tolerant social styles tended to have larger repertoires than less‐tolerant species. These results support the hypothesis that increased social tolerance favors the elaboration of communication to mitigate uncertainty.     

Reconciling community ecology with evidence of animal culture: Socially-adapted,localized community dynamics?

A growing body of empirical research suggests many animal species are capable of social learning and even have cultural behavioral traditions. Social learning has implications for community ecology; changes in behavior can lead to changes in inter- and intra-specific (between and within species) interactions. The paper explores possible implications of social learning for ecological community dynamics. Four arguments are made: (1) social learning can result in locally-specific ecological relationships; (2) socially-mediated, locally-specific ecological relationships can have localized indirect interspecific population effects; (3) the involvement of multiple co-existing species in socially learned, locally-specific behavior has the potential to create community-wide effects, including varying levels of stability and instability; and (4) social learning can create new intra- and inter-specific selection pressures on local taxa, potentially resulting in rapid evolution. Implications of all four arguments are discussed in relation to community ecology research and modeling.     

Nocturnal behavior in a group of unchained female African elephants

The chaining of elephants at night is a common management strategy in zoos, yet the costs and benefits of such a strategy are relatively unknown. A study of three unchained female African elephants was undertaken to document their nocturnal behavior. The subjects were observed between the hours of 1800 and 0800 for 10 weeks in the summer of 1992 (total of 172 hr) and 14 weeks in the summer of 1994 (total of 153 hr). Scan data were collected every 5 min to gather information on activity budgets, social proximity, and space utilization. All‐occurrence data were collected on social and non‐social behaviors. In each year of the study, the subjects spent equivalent amounts of time eating, lying, standing, and walking. Additionally, subjects spent half of their time within one body length of another animal and utilized all three available enclosures. Social and non‐social behaviors were frequent, and these data plus the activity profiles reveal the animals generally were most active between the hours of 1800 and 2400 and 0600 and 0700. The findings suggest that the use of no restraints is currently an effective strategy for this elephant group. The high activity levels observed during many of the early evening hours suggest that zoos could permit increased activity and social interactions by extending the hours when the elephants are unchained. Zoo Biol 18:101–109, 1999. © 1999 Wiley‐Liss, Inc.     

网络分析法在动物声音通讯及生物声学研究中的应用与前景

动物社会网络分析法(animal social network analysis,ASNA)是一套用于研究动物社会性、量化个体间各种社会关系、揭示个体行为与社会结构动态之间联系的工具,被广泛应用于多种动物类群的行为学研究。该分析方法所提供的一系列指标也非常适用于探究动物的声音交流及鸣声结构。在此,本文首先简要介绍了网络分析法的基本概念及一些常用的指标;然后基于野外和室内研究实例,阐述了如何利用ASNA建立声音通讯网络、量化声音交流,以及将ASNA与被动声学监测技术相结合的应用前景;随后探讨了ASNA在分析鸣声相似性及鸣声地理变异中的优势;最后概述了ASNA在解析鸣声结构和句法规则中的应用。ASNA为研究动物通讯网络以及声音信号的适应性进化提供了新的视角和新的思路。     

Social interaction analysis in captive orcas (Orcinus orca)

The management of socially complex species in captivity is challenging. Research on their social behavior improves our understanding of interactions in captive animals and captive‐group management. We conducted a detailed analysis of social relationships shown by the orcas kept at Loro Parque zoo and their tendency to reconcile after aggressive episodes. Affiliative interactions were the most frequent social activities compared to agonistic or sexual interactions. Within affiliative behaviors, we documented the pattern “gentle tongue bite”, where an animal touches the other's tongue with his teeth but does not bite it. Affiliative interactions between a specific pair of orcas occurred significantly more often than expected by chance, and together with low levels of agonistic interactions, indicated particular affinity between some individuals. The most frequently observed low‐level agonistic relationship was that of the two older males (Tekoa–Keto); however, they also showed frequent sexual and affiliative interactions. Sexual‐like behaviors (pursuit, mount, and penis between males) were found in both sexes. Finally, the observed corrected conciliatory tendency (31.57%) was within the range described for other primate and cetacean species. This study provides a systematic way to assess social interactions as well as conflict management strategies in cetaceans housed in zoos and zoo‐like facilities and may help to improve animal welfare and management of animals in controlled environments.     

Small to modest impact of social group on the gut microbiome of wild Costa Rican capuchins in a seasonal forest

The horizontal transmission of pathogenic and beneficial microbes has implications for health and development of socially living animals. Social group is repeatedly implicated as an important predictor of gut microbiome structure among primates, with individuals in neighboring social groups exhibiting distinct microbiomes. Here we examine whether group membership is a predictor of gut microbiome structure and diversity across three groups of white‐faced capuchins (Cebus capucinus imitator) inhabiting a seasonal Costa Rican forest. We collected 62 fecal samples from 18 adult females during four sampling bouts. Sampling bouts spanned the dry‐to‐wet‐to‐dry seasonal transitions. To investigate gut microbial composition, we sequenced the V4 region of the 16S rRNA gene. We used the DADA2 pipeline to assign amplicon sequence variants and the RDP database to classify taxa. Our findings are: 1) gut microbiomes of capuchins clustered by social group in the late dry season, but this pattern was less evident in other sampling bouts; 2) social group was a significant variable in a PERMANOVA test of beta diversity, but it accounted for less variation than season; 3) social group was not an important predictor of abundance for the ten most abundant microbial taxa in capuchins; 4) when examining log2‐fold abundances of microbes between social groups, there were significant differences in some pairwise comparisons. While this is suggestive of group‐wide differences, individual variation may have a strong impact and should be assessed in future studies. Overall, we found a minor impact of social group membership on the gut microbiota of wild white‐faced capuchins. Future research including home range overlap and resource use, as well as fine‐scale investigation of individual variation, will further elucidate patterns of socially structured microbes.     

Anticipated effects of abiotic environmental change on intraspecific social interactions

Social interactions are ubiquitous across the animal kingdom. A variety of ecological and evolutionary processes are dependent on social interactions, such as movement, disease spread, information transmission, and density-dependent reproduction and survival. Social interactions, like any behaviour, are context dependent, varying with environmental conditions. Currently, environments are changing rapidly across multiple dimensions, becoming warmer and more variable, while habitats are increasingly fragmented and contaminated with pollutants. Social interactions are expected to change in response to these stressors and to continue to change into the future. However, a comprehensive understanding of the form and magnitude of the effects of these environmental changes on social interactions is currently lacking. Focusing on four major forms of rapid environmental change currently occurring, we review how these changing environmental gradients are expected to have immediate effects on social interactions such as communication, agonistic behaviours, and group formation, which will thereby induce changes in social organisation including mating systems, dominance hierarchies, and collective behaviour. Our review covers intraspecific variation in social interactions across environments, including studies in both the wild and in laboratory settings, and across a range of taxa. The expected responses of social behaviour to environmental change are diverse, but we identify several general themes. First, very dry, variable, fragmented, or polluted environments are likely to destabilise existing social systems. This occurs as these conditions limit the energy available for complex social interactions and affect dissimilar phenotypes differently. Second, a given environmental change can lead to opposite responses in social behaviour, and the direction of the response often hinges on the natural history of the organism in question. Third, our review highlights the fact that changes in environmental factors are not occurring in isolation: multiple factors are changing simultaneously, which may have antagonistic or synergistic effects, and more work should be done to understand these combined effects. We close by identifying methodological and analytical techniques that might help to study the response of social interactions to changing environments, highlight consistent patterns among taxa, and predict subsequent evolutionary change. We expect that the changes in social interactions that we document here will have consequences for individuals, groups, and for the ecology and evolution of populations, and therefore warrant a central place in the study of animal populations, particularly in an era of rapid environmental change.     

Social network modeling: a powerful tool for the study of group scale phenomena in primates

Social Network Analysis is now a valuable tool to study social complexity in many animal species, including primates. However, this framework has rarely been used to implement quantitative data on the social structure of a group within computer models. Such approaches allow the investigation of how social organization constrains other traits and also how these traits can impact the social organization in return. In this commentary, we discuss the powerful potential of social network modeling as a way to study group scale phenomena in primates. We describe the advantages of using such a method and we focus on the specificity of this approach in primates, given the particularities of their social networks compared with those of other taxa. We also give practical considerations and a list of examples as for the choice of parameters that can be used to implement the social layer within the models.     

Associations between adult spectral tarsiers

While anecdotal observations of gregarious behavior in nocturnal prosimian primates are common, most anthropologists continue to refer to them as solitary, perhaps based on the assumption that the occasional social interactions observed via ad libitum methods represent random chance encounters and not patterned social interactions. In this paper, I test the null hypothesis that nocturnal encounters between spectral tarsier (Tarsius spectrum) group members, outside of the sleeping tree, are the result of chance. Three male‐female pairs were radio‐collared and observed over a 4‐month period, using continuous focal animal sampling at the Tangkoko Nature Reserve (Sulawesi, Indonesia). Using Waser's random gas model, I found that spectral tarsiers spent more time in proximity to other group members than expected by chance, given the size of their home range and nightly path length. Adult group members spent 11% of the night in physical contact and an additional 17% of the night within a 10‐m radius of one another. Spectral tarsiers were also observed to significantly increase the amount of time spent foraging when located less than 10 m from another group member. Individuals foraging in proximity to another adult group member had lower insect capture rates compared to individuals who were not foraging in proximity to another adult group member. If living in a group is costly to these tarsiers' foraging efficiency, then why don't they actively avoid one another when foraging? One situation in which it might benefit tarsiers to be gregarious is high predation pressure. Preliminary results suggest that predation pressure by snakes may be the most likely factor selecting for the tarsiers to forage in proximity. Am J Phys Anthropol 128:74‐83, 2005. © 2005 Wiley‐Liss, Inc.     

Secondarily solitary: the evolutionary loss of social behavior

Studies of social behavior frequently assume that evolution proceeds from a solitary state to a social one, and social to social lineages give rise to line are also social, excluding parasitic taxa. Recent phylogenetic studies of some bees contradict this assumption, and more examples are known or hypothesized in other animals. Social behaviour can be lost to give rise to species that are secondarily solitary. Studies of the conditions to the suppression or loss of social behavior can help to illuminate those factors that lead to its origins and maintenance.     

Social Interactions and the Circadian Rhythm in Locomotor Activity in the Cockroach Leucophaea maderae

The role of social interactions in entrainment has not been extensively studied in the invertebrates. Leucophaea maderae is a gregarious species of cockroach that exhibits extensive social interactions. Social interactions associated with copulation between the sexes have been shown to be regulated by the circadian system. We show here that social interactions between males are also under circadian control. We examined the question of whether or not these rhythmic social contacts could function as zeitgebers capable of regulating circadian phase and period. Animals initially in phase that were housed as groups or pairs of single sex or mixed sex in constant darkness for 2–7 weeks were found to drift out of phase. Their behavior was not significantly different from individual animals maintained in isolation. Further, animals that were initially out of phase by 12 h housed as groups or pairs were not significantly different in phase from animals that were isolated. The results show the circadian clocks of cockroaches are remarkably insensitive to the extensive social interactions that occur between individuals.     

Global positioning system and associated technologies in animal behaviour and ecological research

Biologists can equip animals with global positioning system (GPS) technology to obtain accurate (less than or equal to 30 m) locations that can be combined with sensor data to study animal behaviour and ecology. We provide the background of GPS techniques that have been used to gather data for wildlife studies. We review how GPS has been integrated into functional systems with data storage, data transfer, power supplies, packaging and sensor technologies to collect temperature, activity, proximity and mortality data from terrestrial species and birds. GPS ‘rapid fixing’ technologies combined with sensors provide location, dive frequency and duration profiles, and underwater acoustic information for the study of marine species. We examine how these rapid fixing technologies may be applied to terrestrial and avian applications. We discuss positional data quality and the capability for high-frequency sampling associated with GPS locations. We present alternatives for storing and retrieving data by using dataloggers (biologging), radio-frequency download systems (e.g. very high frequency, spread spectrum), integration of GPS with other satellite systems (e.g. Argos, Globalstar) and potential new data recovery technologies (e.g. network nodes). GPS is one component among many rapidly evolving technologies. Therefore, we recommend that users and suppliers interact to ensure the availability of appropriate equipment to meet animal research objectives.     

Bring your own camera to the trap: An inexpensive,versatile, and portable triggering system tested on wild hummingbirds

The study of animals in the wild offers opportunities to collect relevant information on their natural behavior and abilities to perform ecologically relevant tasks. However, it also poses challenges such as accounting for observer effects, human sensory limitations, and the time intensiveness of this type of research. To meet these challenges, field biologists have deployed camera traps to remotely record animal behavior in the wild. Despite their ubiquity in research, many commercial camera traps have limitations, and the species and behavior of interest may present unique challenges. For example, no camera traps support high‐speed video recording. We present a new and inexpensive camera trap system that increases versatility by separating the camera from the triggering mechanism. Our system design can pair with virtually any camera and allows for independent positioning of a variety of sensors, all while being low‐cost, lightweight, weatherproof, and energy efficient. By using our specialized trigger and customized sensor configurations, many limitations of commercial camera traps can be overcome. We use this system to study hummingbird feeding behavior using high‐speed video cameras to capture fast movements and multiple sensors placed away from the camera to detect small body sizes. While designed for hummingbirds, our application can be extended to any system where specialized camera or sensor features are required, or commercial camera traps are cost‐prohibitive, allowing camera trap use in more research avenues and by more researchers.     

Social cues and hormone levels in male Octodon degus (Rodentia): a field test of the Challenge Hypothesis

Social interactions are important factors determining and regulating individual behaviors. Testosterone has been related to agonistic interactions, while glucocorticoids have been related to social stress, especially during interactions of dominance. We compared testosterone and cortisol concentrations in male degus (Octodon degus, Rodentia) under laboratory conditions without male social interactions, with data from wild males in nature. Under natural conditions, males should present higher levels of testosterone during the breeding season due to social interactions (Challenge Hypothesis). Alternatively, intense social instability could act as a stressing environment, raising glucocorticoids, which inhibit testosterone concentrations. Our results show a significant increase in agonistic interactions between males during the breeding season, and disappearance of non-agonistic male interactions during this period. Hormone levels in breeding season show nonsignificant differences between laboratory groups, but testosterone concentrations in field males were significantly higher than in laboratory males. Testosterone levels were similar among pre-breeding and breeding periods, but in field animals the concentration was approximately 30% higher than in laboratory degus. In field animals, we found two different mating strategies: resident males, with territorial behavior, and transient males, displayed an opportunistic approach to females. Finally, cortisol presents a similar pattern in both laboratory and field animals; pre-breeding values of cortisol are higher than during the breeding season. This suggests that social interactions in O. degus activate a rise in testosterone, supporting the Challenge Hypothesis, and could be considered as partial support of the Social Stress Hypothesis.     

Long‐term monitoring of social behavior in a grouping of six female tigers (Panthera tigris)

Although literature on the reproduction of captive tigers is plentiful, there is little information on other social behaviors, particularly within large social groupings. Here we report on the long‐term monitoring of social behaviors in six female tigers (Panthera tigris). Over a period of 6 years, behavioral data were collected on spraying, vocalizations, non‐contact aggression, and contact aggression during outdoor observations, as well as nearest neighbors in the morning, as a proxy measure of affiliation. Regression analyses showed that non‐contact aggression and vocalizing were increasing, whereas spraying and social proximity were decreasing over the 6 years of the study. Paired t‐tests showed no seasonal differences in aggression, but animals had higher social proximity scores during the mornings of the colder winter months. Correlations showed that spraying was positively related to contact aggression whereas social proximity was negatively correlated with non‐contact aggression. In addition to documenting levels of contact and non‐contact aggression over time, this study showed these behaviors correlated with behaviors that were more easily scored (spraying and social proximity). Behavioral monitoring has played a key role in the management and husbandry of this large social grouping of female tigers. In addition to providing keepers with the opportunity to observe their animals in regularly scheduled sessions, behavioral monitoring has provided baseline information on social relationships in this grouping over time. If future research validates the relationship between aggression and spraying/social proximity, this can be a valuable tool for long‐term monitoring of groups of tigers. Zoo Biol 27:89–99, 2008. © 2007 Wiley‐Liss, Inc.     

Social dominance determines estrous entrainment among female hamsters

In order to study the phenomenon of estrous entrainment and its relation to social behavior two studies were conducted with female hamsters. In the first experiment single females were placed in close proximity, but not in direct contact with three other females whose estrous cycles were already synchronous. The single female was either in phase (control) or out of phase (experimental) with the synchronous females. In the second experiment two females at the same (control) or different (experimental) points in their estrous cycles lived together until entrainment occurred. Their social interactions during the initial 30 min in this shared habitat were observed and a dominance hierarchy established. Estrous stage was determined daily for each animal by vaginal lavage. The major findings of these studies are (1) estrous entrainment occurred in all female hamsters whether living in close proximity (Expt I), or living together (Expt II); (2) regardless of the stage of estrous at the start of cohabitation, hamsters' cycles may be either accelerated or decelerated depending on whether the partner's stage is ahead or behind their own; (3) social interaction appears to accelerate the entrainment process, and (4) when examined in light of social dominance, the behaviorally submissive animals entrained to the behaviorally dominant animals.     

Experimental Validation of Sex Differences in Spatial Behavior Patterns of Free‐Ranging Snakes: Implications for Social Interactions

Social interactions often play a significant role in determining patterns of spatial use. Although snakes are generally thought of as asocial, recent spatial dispersion studies suggest that the spatial ecology of snakes may be more strongly influenced by social interactions than previously thought. We investigated the spatial behavior patterns of a western cottonmouth (Agkistrodon piscivorus) population in east Texas by uniquely combining radio‐telemetry studies on free‐ranging snakes with experimental arena trials with captive individuals from the same population. Observations from the radio‐telemetry study on free‐ranging A. piscivorus indicated that females were more gregarious than males. In the follow‐up study, spatial dispersion data from captive snakes maintained in experimental field arenas yielded similar results to spatial behavior patterns of free‐ranging individuals. When compared to random experimental controls, these data suggest that observed spatial behavior patterns are related to mechanisms associated with both active avoidance among males and conspecific attraction among females. In addition to uniquely combining both free‐ranging and captive observations, this is the first snake study to demonstrate sex differences with both of these divergent (attraction and avoidance) spatial patterns within a single population. Thus, similar to other vertebrate groups, a growing body of literature suggests that social interactions in snakes should be strongly considered in interpretations of spatial ecology and behavior.