Search Results (16)

The assessment of animal welfare in rehabilitation settings is a critical aspect of effective care, yet typical metrics often fail to fully capture rehabilitating animals’ emotional experiences in a non-invasive way. Anticipatory behavior has emerged as a promising animal welfare indicator, reflecting an animal’s perceived need for rewards based on available opportunities in their environment. By tracking anticipatory responses, caretakers can gain insight into an animal’s reward sensitivity and use this information to guide management interventions. This study investigated the effects of enrichment type on anticipatory behavior in fourteen, rehabilitating harbor seal pups (Phoca vitulina richardii). We provided pups with daily sessions of either structural or cognitive enrichment and recorded their behavioral responses. During scheduled feeding sessions, we identified behaviors that emerged as anticipatory, then measured the frequency and duration of anticipatory behavior prior to the feeds to assess how enrichment types influenced the seals’ reward sensitivity, and thus their welfare. While enrichment interaction did not directly modulate anticipatory behavior, we observed a trend suggesting that exposure to cognitive enrichment reduced anticipatory behavior duration compared to structural enrichment. These findings align with previous research in zoo settings, where cognitive enrichment has been linked to improved welfare through reduced anticipatory behavior, though this effect has not been explored in a wildlife rehabilitation context. This study highlights the value of anticipatory behavior as a practical welfare assessment tool in rehabilitation settings and underscores the potential for enrichment, particularly cognitive, to improve welfare in rehabilitating marine mammals. Full article

Cognitive enrichment is increasingly recognized as an important component of marine mammal welfare, offering animals opportunities for choice, problem solving, and sustained engagement. Personality research has also shown that stable individual differences can influence how animals interact with enrichment, training, and their environment. This study examined how trainer-assessed personality traits related to interaction patterns with a computerized enrichment system in California sea lions (Zalophus californianus). Using validated personality surveys, reliability testing, and hierarchical clustering, trait structures were derived and compared with objective, system-generated gameplay measures. Analyses revealed meaningful associations that emphasize the value of considering temperament when designing enrichment and welfare programs. By integrating personality assessment with technology-based enrichment systems, this work demonstrates how individualized approaches can enhance welfare and provide new insights into enrichment design and animal cognition. Although limited in scope and sample size, the findings suggest that computerized enrichment has potential as both a welfare tool and a research platform, with value in considering personality and individual variation for broader applications across species and settings. Full article

Animal protein production represents a complex system of lives transformed into nutrition, with profound ethical and environmental implications. This study provides a quantitative analysis of animal lives required to produce human-consumable protein across major food production systems. Categorizing animal lives based on cognitive complexity and accounting for all lives involved in production, including direct harvests, reproductive animals, and feed species, reveals dramatic variations in protein efficiency. The analysis considers two categories of animal life: complex-cognitive lives (e.g., mammals, birds, cephalopods) and pain-capable lives (e.g., fish, crustaceans). Calculating protein yield per life demonstrates efficiency differences spanning more than five orders of magnitude, from 2 g per complex-cognitive life for baby octopus to 390,000 g per life for bovine dairy systems. Key findings expose disparities between terrestrial and marine protein production. Terrestrial systems involving mammals and birds show higher protein yields and exclusively involve complex-cognitive lives, while marine systems rely predominantly on pain-capable lives across complex food chains. Dairy production emerges as the most efficient system. Aquaculture systems reveal complex dynamics, with farmed carnivorous fish requiring hundreds of feed fish lives to produce protein, compared to omnivorous species that demonstrate improved efficiency. Beyond quantitative analysis, this research provides a framework for understanding the ethical and ecological dimensions of protein production, offering insights for potential systemic innovations. Full article

Cetaceans are highly adapted to the underwater environment, which is very different from the terrestrial environment. For cetaceans with neither high visual acuity nor color vision, contrast may be an important cue for visual object recognition, even in the underwater environment. Contrast is defined as the difference in luminance between an object and its background and is known to be perceived as enhanced by the luminance contrast illusion in humans. The aim of this study was to experimentally investigate whether the enhancement of contrast by the luminance contrast illusion could be observed in killer whales. Luminance discrimination tasks were performed on two captive killer whales, which were required to compare the luminance of two targets presented in monitors through an underwater window and to choose the brighter one. After baseline training, in which the target areas were surrounded by black or white inducer areas, the test condition of gray inducer areas was added. Although there were some individual differences, both individuals showed higher correct response rates for gray inducer conditions than for black and white. The results suggest that contrast was perceived as enhanced by the illusion also in killer whales and may help them to extract the contours of objects. Full article

Cognitive enrichment is becoming more prevalent in professional marine mammal facilities. Research with dolphins has suggested that such enrichment provides more welfare benefits than enrichment that does not incorporate cognitive challenge. However, there is little research supporting the use of cognitive enrichment as a means to improve the welfare of sea lions. Recently, a novel form of technological cognitive enrichment, the Enclosure Video Enrichment (EVE) system, was introduced to a population of California sea lions at the US Navy’s Marine Mammal Program as a means to enhance welfare. Two of the initial focal animals introduced to EVE were selected based on their health history and the possible benefits of cognitive enrichment in improving health measures. To evaluate this, information regarding the animals’ consumption of their offered diet was compared to other animals in the population of similar age and the absence of a similar health history. Subsequently, the total diet consumption of the targeted animals was evaluated in the two years prior to the introduction to EVE and compared to the total diet consumption during the initial 2 years of regular EVE sessions. There was a significant decrease in the number of days in which the sea lions did not consume their entire offered diet in the two years after implementing regular EVE sessions, an increase in participation and performance of voluntary husbandry behaviors, and a reduction in the number of days animals were clinically ill. This study provides evidence of cognitive enrichment as a management tool to improve animal health and welfare as well as performance in training sessions. Full article

The past several decades have witnessed significant improvement in the physical welfare of marine mammals in zoos and aquariums. Over that same time period, research has revealed complex cognitive abilities in at least some of these species, yet there has been comparatively little attention paid to addressing their cognitive welfare per se. Studies primarily conducted with terrestrial animals have suggested that providing appropriate cognitive challenges in managed care settings can improve animal well-being. As a step toward facilitating this practice with marine mammals, this paper discusses factors relevant for creating appropriate cognitive challenges, outlines the three major categories of cognitive challenge that have been utilized with marine mammals, along with the logistical pros and cons of each, and calls on organizations that care for marine mammals to cultivate a bias for action with respect to providing cognitive care. Full article

Matching-to-sample tasks have been a useful method in visual cognitive studies on non-human animals. The use of touch panels in matching-to-sample tasks has contributed to cognitive studies on terrestrial animals; however, there has been a difficulty in using these devices underwater, which is one of the factors that has slowed the progress of visual studies on underwater animals. Cetaceans (e.g., dolphins and whales) are highly adapted to underwater environments, and further studies on their cognitive abilities are needed to advance our understanding of the interactions between environmental factors and the evolution of cognitive abilities. In this study, we aimed to develop a new experimental method in which a captive killer whale performed a matching-to-sample task using a monitor shown through an underwater window as if a touch panel were used. In order to confirm the usefulness of this method, one simple experiment on mirror image discrimination was conducted, and the pairs with mirror images were shown to be more difficult to identify than the pairs with other normal images. The advantages of using this method include (1) simplicity in the devices and stimuli used in the experiments, (2) appropriate and rigorous experimental control, (3) the possibility of increasing the number of individuals to be tested and interspecies comparisons, and (4) contributions to animal welfare. The use of this method solves some of the problems in previous visual cognitive studies on cetaceans, and it suggests the further possibility of future comparative cognitive studies. It is also expected to contribute to animal welfare in terms of cognitive enrichment, and it could help with the proposal of new exhibition methods in zoos and aquariums. Full article

Cetaceans are well known for their unique behavioral habits, such as calls and tactics. The possibility that these are acquired through social learning continues to be explored. This study investigates the ability of a young beluga whale to imitate novel behaviors. Using a do-as-other-does paradigm, the subject observed the performance of a conspecific demonstrator involving familiar and novel behaviors. The subject: (1) learned a specific ‘copy’ command; (2) copied 100% of the demonstrator’s familiar behaviors and accurately reproduced two out of three novel actions; (3) achieved full matches on the first trial for a subset of familiar behaviors; and (4) demonstrated proficiency in coping with each familiar behavior as well as the two novel behaviors. This study provides the first experimental evidence of a beluga whale’s ability to imitate novel intransitive (non-object-oriented) body movements on command. These results contribute to our understanding of the remarkable ability of cetaceans, including dolphins, orcas, and now beluga whales, to engage in multimodal imitation involving sounds and movements. This ability, rarely documented in non-human animals, has significant implications for the development of survival strategies, such as the acquisition of knowledge about natal philopatry, migration routes, and traditional feeding areas, among these marine mammals. Full article

When marine animals and underwater acoustic sensor networks (UASNs) share spectrum resources, problems such as serious harm caused to marine animals by underwater acoustic systems and scarcity of underwater spectrum resources are encountered. To address these issues, a mammal-friendly underwater acoustic sensor network channel power allocation algorithm is proposed. Firstly, marine animals are treated as authorized users and sensor nodes as unauthorized users. Considering the interference level of sensor nodes on authorized users, this approach improves network service quality and achieves a mammal-friendly underwater communication mechanism. Secondly, to maximize the utility of unauthorized users, the algorithm incorporates a network interference level and node remaining energy into a game-theoretical framework. Using channel allocation and power control, a game model is constructed with a unique Nash equilibrium point. Finally, through simulation, it can be found that the proposed algorithm can obtain a stable optimal power value, and with the increase of network load, the system capacity of the proposed algorithm is significantly improved than that of the traditional cognitive radio technology and the common spectrum allocation algorithm, and the transmitted power of nodes can be controlled according to the size of the residual energy, so as to comprehensively improve the overall performance of the network. Full article

The order Sirenia comprises several species of manatees and one species of dugong. These popular marine mammals are relatively recent acquisitions to zoological parks throughout the world. As far as we know, there are less than 200 manatees, mostly American, a few African, and ever less Amazonian, currently in zoological parks. American manatees are predominantly found in zoos in Europe, North America, and in some Asian countries, while African ones are present exclusively in Asian zoos. The living conditions of captive manatees differ considerably from zoo to zoo (i.e., numbers, sex ratio, outdoor vs. indoor habitats, complex vs. simple habitats). Most research on manatee behaviour has been relatively recent, and studies on cognition, sociality, and ecology have a significant impact on our perception of manatee needs and management, with wider implications for their welfare. In the wild, manatees demonstrated various cognitive capacities; spatial memory and learning abilities play an important role in their daily life in a complex and dynamic environment. Furthermore, there is evidence that these mammals are more social animals than expected. Individuals show various personality traits on the boldness–shyness continuum and their sociality varies. All those parameters are important in terms of animal welfare. Several behavioural studies showed that standardized enrichment programs benefit and ensure the welfare of captive zoo animals. However, obtaining accurate information on the presence of manatees in zoos, living conditions, management, and consequently welfare remains challenging. This study examines the current knowledge on manatee behaviour and cognition and then discusses different approaches to improving the welfare of this charismatic marine mammal in zoological parks. Full article

Environmental pollutants have become quite ubiquitous over the past two centuries; of those, plastics, and in particular, microplastics (<5 mm), are among the most pervasive pollutants. Microplastics (MPs) have found their way into the air, water system, and food chain and are either purposely produced or are derived from the breakdown of larger plastic materials. Despite the societal advancements that plastics have allowed, the mismanagement of plastic waste has become a pressing global issue. Pioneering studies on MPs toxicity have shown that exposure to MPs induces oxidative stress, inflammation, and decreased cell viability in marine organisms. Current research suggests that these MPs are transported throughout the environment and can accumulate in human tissues; however, research on the health effects of MPs, especially in mammals, is still very limited. This has led our group to explore the biological and cognitive consequences of exposure to MPs in a rodent model. Following a three-week exposure to water treated with fluorescently-labeled pristine polystyrene MPs, young and old C57BL/6J mice were assessed using behavioral assays, such as open-field and light–dark preference, followed by tissue analyses using fluorescent immunohistochemistry, Western blot, and qPCR. Data from these assays suggest that short-term exposure to MPs induces both behavioral changes as well as alterations in immune markers in liver and brain tissues. Additionally, we noted that these changes differed depending on age, indicating a possible age-dependent effect. These findings suggest the need for further research to better understand the mechanisms by which microplastics may induce physiological and cognitive changes. Full article

The effects of anthropogenic noise continue to threaten marine fauna, yet the impacts of human-produced sound on the broad aspects of cognition in marine mammals remain relatively understudied. The shutdown of non-essential activities due to the COVID-19-related anthropause created an opportunity to determine if reducing levels of oceanic anthropogenic noise on cetaceans affected processes of sensitization and habituation for common human-made sounds in an experimental setting. Dolphins at Dolphin Quest Bermuda were presented with three noises related to human activities (cruise ship, personal watercraft, and Navy low-frequency active sonar) both in 2018 and again during the anthropause in 2021 via an underwater speaker. We found that decreased anthropogenic noise levels altered dolphin responses to noise playbacks. The dolphins spent significantly more time looking towards the playback source, but less time producing burst pulse and echolocation bouts in 2021. The dolphins looked towards the cruise ship sound source significantly more in 2021 than 2018. These data highlight that different sounds may incur different habituation and sensitization profiles and suggest that pauses in anthropogenic noise production may affect future responses to noise stimuli as dolphins dishabituate to sounds over time. Full article

Cognitive enrichment for professionally managed species has become more prevalent in recent years in both zoological and research settings and has been encouraged as a means of welfare enhancement. However, the task’s difficulty must be specifically tailored as it can impact the successful nature of the sessions, as tasks that are too simple or difficult may not be perceived as enriching by the animals. While pinnipeds are common in zoos, aquariums, and research facilities, few studies have explored the use of cognitively challenging enrichment in this species, and the level of difficulty and presence of failure on animal success and engagement in this type of session has not been assessed. In this study, gameplay strategies during computerized enrichment sessions were evaluated before and after a game that introduced failure, or the loss of opportunity to complete a level for a reward after an incorrect movement. Interest in participation during the session, measured as the latency without contact, was also tested as a proxy for this enrichment’s effect on welfare. When incorrect movements resulted in a short pause and removed the opportunity to finish individual levels for a reward, all three sea lions tested significantly reduced the amount of time spent on each of several strategies they employed, but significantly increased the number of button presses per strategy, suggesting the animals focused on more precise movements as their proficiency improved. Two sea lions also showed a significant decline in latency without contact following the introduction of failure in the form of a single opportunity to complete a task for a reward after previously having unlimited opportunities, while one maintained a low latency without contact across both test conditions. The results suggest that more cognitively challenging tasks incorporating failure did not cause a reduction in gameplay performance and session interest in sea lions. Individual variation was also noted in strategy use, emphasizing the importance of evaluating the individual in terms of enrichment provision. Full article

Ecosystems are increasingly involved and influenced by human activities, which are ever-increasing. These activities are mainly due to vehicular, air and sea transportation, thus causing possible repercussions on the fauna that exists there. The aim of this systematic review is to investigate the possible consequences that these activities may have in the field of animal neurobehavior, with special emphasis on the species involved, the most common environment concerned, the noise source and the disturbance that is caused. This research includes articles published in the major databases (PubMed, Cochrane Library, Scopus, Embase, Web of Sciences); the online search yielded 1901 references. After selection, 49 articles (14 reviews and 35 original articles) were finally scrutinized. The main problems that were reported were in relation to movement, reproduction, offspring care and foraging. In live experiments carried out, the repercussions on the marine environment mainly concerned altered swimming, shallower descents, less foraging and an escape reaction for fear of cetaceans and fish. In birds, alterations in foraging, vocalizations and nests were noted; laboratory studies, on the other hand, carried out on small mammals, highlighted spatio-temporal cognitive alterations and memory loss. In conclusion, it appears that greater attention to all ecosystems should be given as soon as possible so as to try to achieve a balance between human activity and the well-being of terrestrial fauna. Full article

Captive mammals respond emotionally toward cognitive challenges, but research has precluded marine mammals. A potential indicator of emotion in toothed cetaceans is a large singular bubble (‘burst’) emitted from the blowhole, previously linked to surprise and excitement. Our study analysed bursts from a published study on dolphin cognitive enrichment. Bursts were only produced by task-engaged (72%) or task-spectating (28%) dolphins (n = 6 males in total). Burst frequency increased with the proportion of task engagement and spectator frequency, but not task progress or success (providing no evidence for an instantaneous ‘Eureka moment’). Bursts were reduced in frequency over three weeks, consistent with a decrease in task-engagement. Bursts were significantly more likely to come at the start of a bout of task-engagement than in the middle or end. We suggest bursts were an emotional response signaling dolphins’ instantaneous judgement of the task, more likely related to positive affect (interest, curiosity) than negative affect (frustration). They appear unrelated to respiration. It was unclear whether bursts were produced consciously and had a social function. We call for further dedicated research on the emotional valence of cetacean bursts. This will require simultaneous behavioural and acoustic measurements under different levels of more controlled challenge. Full article