29 research outputs found
Seasonal and Diurnal Patterns of Behavior Exhibited by Atlantic Bottlenose Dolphins (\u3ci\u3eTursiops truncatus\u3c/i\u3e) in the Mississippi Sound
Many of the threats to bottlenose dolphins are anthropogenic factors including overfishing, high-speed boats, chemical runoff, and noise pollution. Having a thorough understanding of the behavior and behavioral patterns of these animals can help with conservation plans to protect this species. This study examined the behavioral states and behavioral events of Atlantic bottlenose dolphins (Tursiops truncatus) in the Mississippi Sound. The behavioral states exhibited by dolphins within the Sound were found to vary by both season and time of day. Dolphins socialized more during the spring and spent more time feeding in the fall. Feeding was highest early in the morning and decreased throughout the day, while socializing occurred at low levels in the morning and increased in the early afternoon. Two distinct forms of social behavior and multiple feeding strategies were exhibited by dolphins within the Sound. Results suggest that certain percussive behavioral events may be used to communicate motivation during transitional behavioral states. These results demonstrate the need for a more complete understanding of dolphin behavior that will facilitate the conservation of this species
Recommended from our members
Recognition and Discrimination of Human Actions Across the Senses of Echolocation and Vision in the Bottlenose Dolphin: Evidence for Dolphin Cross-modal Integration of Dynamic Information
The ability of cetaceans to explore and interpret their world via echolocation has receivedconsiderable attention during recent years, and the resulting body of work has revealed asophisticated cetacean echolocation system. In addition, a number of recent studies suggest thatdolphins can relate information that they receive from vision with information that they obtainfrom echolocation when this information concerns stationary objects. However, the present studyis the first test of the cetacean ability to integrate dynamic information about movement acrossthe two senses. Three adult female bottlenose dolphins that had previously learned to interpretvisible movements produced by humans stationed on floating docks were asked to interpret a setof these movements produced by an underwater human located behind a visually opaque screen.Although each dolphin had previously demonstrated its ability to reliably interpret movementsproduced by a human in the air above the surface of the water, none of the dolphins had anyprevious experience with underwater humans producing movements that the dolphins could seeor with underwater humans producing movements behind an opaque screen that prevented thedolphins from using visual information to interpret these signals. The dolphins quickly learned tocorrectly respond to signals that they could not see but could observe via echolocation. Theseresults demonstrate that dolphins can relate visual and echoic representations of actions,although the amount of experience necessary for such integration has yet to be determined
Immediate Response of Atlantic Bottlenose Dolphins to High-Speed Personal Watercraft in the Mississippi Sound
Measuring the impact of anthropogenic factors on marine mammals is critical to the conservation of these species. Recently, the effect of personal watercraft on marine mammal behaviour and well-being has become a topic of increasing concern. 7 lie purpose of this study was to examine the immediate effects of high-speed personal watercraft on Atlantic bottlenose dolphin (Tursiops truncatus) behaviour. Opportunistic surveys were conducted front a research vessel in the Mississippi Sound (30 degrees 13 \u27 22.6 \u27\u27 N 89 degrees 0.1 \u27 36.5 \u27\u27 W)from September 2003 through to August 2005. The passing of a high-speed personal watercraft significantly increased dolphin dive duration, dolphin group cohesion and dolphin breathing synchrony. Additionally, in 47% of the encounters a dolphin groups behaviour changed within one minute of the presence of a high-speed personal watercraft. The most notable changes were tin increase in dolphin travelling behaviour and a decrease in feeding behaviour following the boat\u27s presence. The results demonstrated an immediate, short-term change in dolphin behaviour, suggesting that all increase in the frequency of high-speed personal watercraft in this area could produce long-term detrimental effects. Research on the long-term effects of boat traffic on marine mammals is clearly needed to assess and hopefully mediate any potential long-term effects
Time and Frequency Parameters of Bottlenose Dolphin Whistles as Predictors of Surface Behavior in the Mississippi Sound
Acoustic characteristics related to contour of the whistle (such as highest and lowest frequency, beginning and ending frequency, whistle duration, and number of turns) of bottlenose dolphin (Tursiops truncatus) whistles were measured to test whether any of the measurements were related to the behavioral state of the dolphins when the whistle was recorded (coded as mill, travel, mill/travel, feed, or social). Objective measures of time and frequency were obtained using Raven, while number of turns in a whistle was determined by human raters. In all a series of discriminant function analyses using the acoustic characteristics to predict the behavioral state, the highest standardized canonical discriminant function coefficients were: lowest frequency, number of turns, and duration. The models that incorporated these variables performed significantly better than chance at correctly assigning the whistles into the surface behavior category in which they were recorded. The rate of whistling was related to group size, surface behavior and season via a series of two-way ANOVAs (analysis of variance). (C) 2010 Acoustical Society of America. [DOI: 10.1121/1.3365254
Recommended from our members
Seasonal, Diel, and Age Differences in Activity Budgets of a Group of Bottlenose Dolphins (Tursiops truncatus) Under Professional Care
Wild bottlenose dolphin (Tursiops truncatus) behavior is impacted by a number of factors including season, time of day, and age. However, less is known about how these factors may influence animals under professional care in zoos, aquariums and marine parks. Management practices such as scheduled feeding times, human interactions, lack of predators and show performances may also impact the activity budgets of dolphins. The current study examined the rest, swim and play behavior of seven dolphins (three adults, four calves) at one facility. Data were collected over the entire 24-hour day for a period of one year. Observed behaviors were recorded in mutually exclusive categories including rest, low intensity swim, high intensity swim, low intensity play, high intensity play and social play. Data were analyzed to determine how often dolphins engaged in particular behaviors and if activity budgets varied due to season, time of day and age.  These dolphins spent the majority of their time in low intensity swim and low intensity play. The activity budget varied between observational periods. First, seasonal differences were found in low intensity swim, low intensity play, social play and high intensity play behaviors. In the comparison for time of day, differences were found in rest, low intensity swim, low intensity play and social play. Finally, no significant differences were found in age comparisons. Information gained from this study can help to better understand how different factors influence the behavior of bottlenose dolphins under professional care within zoos, aquariums and marine parks
Seasonal, Diel, and Age Differences In Activity Budgets of a Group of Bottlenose Dolphins (\u3ci\u3eTursiops truncatus\u3c/i\u3e) Under Professional Care
© 2017 International Journal of Comparative Psychology. Wild bottlenose dolphin (Tursiops truncatus) behavior is impacted by a number of factors including season, time of day, and age. However, less is known about how these factors may influence animals under professional care in zoos, aquariums and marine parks. Management practices such as scheduled feeding times, human interactions, lack of predators and show performances may also impact the activity budgets of dolphins. The current study examined the rest, swim and play behavior of seven dolphins (three adults, four calves) at one facility. Data were collected over the entire 24-hour day for a period of one year. Observed behaviors were recorded in mutually exclusive categories including rest, low intensity swim, high intensity swim, low intensity play, high intensity play and social play. Data were analyzed to determine how often dolphins engaged in particular behaviors and if activity budgets varied due to season, time of day and age. These dolphins spent the majority of their time in low intensity swim and low intensity play. The activity budget varied between observational periods. First, seasonal differences were found in low intensity swim, low intensity play, social play and high intensity play behaviors. In the comparison for time of day, differences were found in rest, low intensity swim, low intensity play and social play. Finally, no significant differences were found in age comparisons. Information gained from this study can help to better understand how different factors influence the behavior of bottlenose dolphins under professional care within zoos, aquariums and marine parks
Population Abundance and Habitat Utilization of Bottlenose Dolphins in the Mississippi Sound
Distance sampling principles were utilized to examine population density and abundance for bottlenose dolphins (Tursiops truncatus) in the Mississippi Sound. Information was collected during summer and winter to allow for examination of habitat utilization and abundance during two different seasons.Within the study area of the Mississippi Sound there are approximately 2225 bottlenose dolphins. The population was larger during the summer than during the winter months.Dolphins utilized coastal areas more during the summer, potentially as nursery grounds, as evidenced by larger numbers of calves and percentage of groups containing calves during this time. Bottlenose dolphin densities were lower in this area during the winter suggesting migration to deeper waters potentially in search of prey.As the Mississippi Sound is regularly utilized for a variety of human activities, the monitoring of dolphin populations in this area is critical to determine increasing or decreasing trends in population abundance due to potential anthropogenic factors that may affect animal populations.Similar studies around the world could provide evidence for areas that could be protected to ensure survival of species such as dolphins and other marine mammals
Recommended from our members
Keeping Environmental Enrichment Enriching
The use of novel objects as environmental enrichment devices is a key aspect of many environmental enrichment programs, regardless of whether the animals being enriched are housed in aquaria, zoos, or laboratories. The effectiveness of novel objects as enrichment devices depends on a number of factors, many of which are based on findings from comparative psychology. For example, the literature on habituation predicts that an object that is always in an animal’s environment will be less interesting than a similar object that is available only on an intermittent basis. To test the hypothesis that type of exposure to objects affects the objects’ enriching qualities, we exposed sixteen animals from ten different species to novel objects in two different conditions. In the first condition, animals were exposed to a novel object for a total of 120 min, 60 min at a time on two separate occasions. Approximately three weeks later, the animals were once again given a total of 120 min to interact with the object that they had experienced in the first condition, but the amount of time the object was available per session was much more variable. The results demonstrate that variable presentations are more likely to maintain the enriching qualities of objects, consistent with the literature on habituation
Recommended from our members
All Mothers are Not the Same: Maternal Styles in Bottlenose Dolphins (Tursiops truncatus)
A dolphin calf’s relationship with its mother is crucial for its survival and may be affected by the mother’s preferred mode of interacting with her calf. Mothers from a variety of species exhibit individual differences and stable maternal styles. However, little is known about individual differences in the maternal behaviors of dolphins. We investigated the possibility of maternal styles in dolphins by identifying specific maternal care behaviors in 7 dolphin mothers at two facilities during the first year of each calf’s life. The mothers exhibited different patterns of behavior including proximity maintenance, discipline, and initiation of separations and reunions with calves. These patterns of maternal behaviors suggest that dolphin mothers display a range of maternal styles that appear to be differentiated by level of maternal control. Moreover, a mother may also modify her individual style as her calf matures and as the social context changes