scholarly journals Vocal correlates of arousal in bottlenose dolphins (Tursiops spp.) in human care

PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0250913
Author(s):  
Rachel Probert ◽  
Anna Bastian ◽  
Simon H. Elwen ◽  
Bridget S. James ◽  
Tess Gridley

Human-controlled regimes can entrain behavioural responses and may impact animal welfare. Therefore, understanding the influence of schedules on animal behaviour can be a valuable tool to improve welfare, however information on behaviour overnight and in the absence of husbandry staff remains rare. Bottlenose dolphins (Tursiops spp.) are highly social marine mammals and the most common cetacean found in captivity. They communicate using frequency modulated signature whistles, a whistle type that is individually distinctive and used as a contact call. We investigated the vocalisations of ten dolphins housed in three social groups at uShaka Sea World dolphinarium to determine how patterns in acoustic behaviour link to dolphinarium routines. Investigation focused on overnight behaviour, housing decisions, weekly patterns, and transitional periods between the presence and absence of husbandry staff. Recordings were made from 17h00 – 07h00 over 24 nights, spanning May to August 2018. Whistle (including signature whistle) presence and production rate decreased soon after husbandry staff left the facility, was low over night, and increased upon staff arrival. Results indicated elevated arousal states particularly associated with the morning feeding regime. Housing in the pool configuration that allowed observation of staff activities from all social groups was characterised by an increase in whistle presence and rates. Heightened arousal associated with staff presence was reflected in the structural characteristics of signature whistles, particularly maximum frequency, frequency range and number of whistle loops. We identified individual differences in both production rate and the structural modification of signature whistles under different contexts. Overall, these results revealed a link between scheduled activity and associated behavioural responses, which can be used as a baseline for future welfare monitoring where changes from normal behaviour may reflect shifts in welfare state.

2021 ◽  
Author(s):  
Rachel Probert ◽  
Anna Bastian ◽  
Simon Elwen ◽  
Bridget James ◽  
Tess Gridley

Human-controlled regimes can entrain behavioural responses and may impact animal welfare. Therefore, understanding the impact of schedules on animal behaviour can be a valuable tool to improve welfare, however information on overnight behaviour and behaviour in the absence of husbandry staff remains rare. Bottlenose dolphins ( Tursiops spp.) are highly social marine mammals and the most common cetacean found in captivity. They communicate using frequency modulated signature whistles which are individually distinctive and used as a contact call. We investigated the vocal behaviour of ten dolphins housed in three social groups at uShaka Sea World dolphinarium to determine how acoustic behavioural patterns link to dolphinarium routines. Investigation focused on overnight behaviour, housing decisions, weekly patterns, and transitional periods between presence and absence of husbandry staff. Recordings were made from 17h00 – 07h00 over 24 nights, spanning May to August 2018. Whistle production rate decreased soon after husbandry staff left the facility, was low over night, and increased upon arrival. Results indicated elevate arousal states associated with the morning arrival and presence of husbandry staff and heightened excitement associated with feeding. Housing in pool configurations which limited visual contact between certain groups were characterised by lower vocal production rates. Production of signature whistles was greater over the weekends compared to weekdays however total whistle production did not differ between weekends and weekdays. Heightened arousal associated with staff arrival was reflected in the structural characteristics of signature whistles, particularly maximum frequency, frequency range and number of whistle loops. Overall, these results revealed a link between scheduled activity and associated behavioural responses, which can be used as a baseline for future welfare monitoring where changes in normal behaviour may reflect shifts in welfare state.


2020 ◽  
Vol 181 ◽  
pp. 104255
Author(s):  
Juliana Lopez-Marulanda ◽  
Heiko G. Rödel ◽  
Nikolaas Colpaert ◽  
Sander Vanderheul ◽  
Olivier Adam ◽  
...  

2020 ◽  
Vol 21 (7) ◽  
Author(s):  
Aryani Sismin Satyaningtijas ◽  
AGUSTIN INDRAWATI ◽  
RIZKA F. SYARAFINA ◽  
TALITA F. MILANI ◽  
M. SURYAPUTRA ◽  
...  

Abstract. Satyaningtijas AS, Indrawati A, Syarafina RF, Milani TF, Saleema AK. 2020. Short Communication: Erythrocytes and leukocytes profiles of bottlenose dolphins (Tursiops aduncus) at conservation site. Biodiversitas 21: 3359-3363. Health monitoring of dolphins to ensure optimal welfare in human care is important. This study measured erythrocytes and leukocytes in seven bottlenose dolphins (Tursiops aduncus) as a parameter to assess physiological status in PT. Wersut Seguni Indonesia (WSI) Marine Mammals Conservation. Blood was sampled through the superficial veins of each tail fin for examination of erythrocytes and leukocytes using hemocytometer method. Differential leukocytes were observed using thin blood smears stained by Giemza. The purpose of this study to collect hematological value of captive bottlenose dolphins. The results showed values of erythrocytes was (5.14±0.56) x 106/mm3, (13.86±1.68) gr/dl for hemoglobin, and (44.29±2.69)% for hematocrit. The value for leukocytes were  (4.2 ± 0,82) x 103/mm3 , 63.14 ± 9.77% for lymphocytes, 3.57 ± 1.72% for monocytes, 31.57 ± 8.43% for neutrophils, 1.29 ± 1.60% for eosinophils and 0.14 ± 0.38% for basophils. The average of the seven bottlenose dolphins Neutrophil to Lymphocyte ratio (N/L) was 0.53.


2021 ◽  
Vol 13 (1) ◽  
pp. 156
Author(s):  
Joana Castro ◽  
Francisco O. Borges ◽  
André Cid ◽  
Marina I. Laborde ◽  
Rui Rosa ◽  
...  

Unmanned Aerial Vehicles (UAVs), or drones, have recently emerged as a relatively affordable and accessible method for studying wildlife. Vertical Take-off and Landing (VTOL) UAVs are appropriate for morphometric, behavioural, abundance and demographic studies of marine mammals, providing a stable, nonintrusive and highly manoeuvrable platform. Previous studies using VTOL UAVs have been conducted on various marine mammal species, but specific studies regarding behavioural responses to these devices are limited and scarce. The aim of this study was to evaluate the immediate behavioural responses of common (Delphinus delphis) and bottlenose (Tursiops truncatus) dolphins to a VTOL UAV flown at different altitudes. A multirotor (quadcopter) UAV with an attached GoPro camera was used. Once a dolphin group was located, the UAV was flown at a starting height of 50 m directly above the group, subsequently descending 5 m every 30 s until reaching 5 m. We assessed three behavioural responses to a VTOL UAV at different heights: (i) direction changes, (ii) swimming speed and (iii) diving. Responses by D. delphis (n = 15) and T. truncatus (n = 10) groups were analysed separately. There were no significant responses of T. truncatus to any of the studied variables. For D. delphis, however, there were statistically significant changes in direction when the UAV was flown at a height of 5 m. Our results indicate that UAVs do not induce immediate behavioural responses in common or bottlenose dolphins when flown at heights > 5 m, demonstrating that the use of VTOL UAVs to study dolphins has minimal impact on the animals. However, we advise the use of the precautionary principle when interpreting these results as characteristics of this study site (e.g., high whale-watching activity) may have habituated dolphins to anthropogenic disturbance.


Animals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 2107
Author(s):  
Tim Huettner ◽  
Sandra Dollhaeupl ◽  
Ralph Simon ◽  
Katrin Baumgartner ◽  
Lorenzo von Fersen

Zoos and aquaria must provide optimal husbandry conditions and the highest welfare standards for their animals. How the welfare state of an animal or a group of animals can be precisely assessed is currently under debate, and new approaches are necessary to reliably evaluate changes in welfare. One particular measure that is easily applicable is behavioral observations. However, for dolphins and other cetaceans under human care, reliable behavior-based measures are rare. Using long-term observations of a group of bottlenose dolphins, we investigate how their activity budgets and different behaviors changed over time and are impacted by construction noise. Additionally, we investigate whether behavioral differences are also reflected in changes in the dolphins’ performance during daily training sessions. Our results show that construction noise significantly alters the dolphins’ behavior. Play behavior decreases during construction periods; most importantly, the frequency of fast swimming activities significantly increased, and at the same time, a decrease in training performance is found. Additionally, inter- and intraindividual behavioral differences are attributed to factors, such as age or weaning. Significant changes in a dolphin’s activity budget can also pose potential welfare concerns. Thus, this study highlights the importance of regularly assessing and analyzing the behavior of dolphins under human care. Behavioral observations are essential welfare indicators and can—when complemented with other measures, such as assessment of training performance—provide zoo staff with important information about each individual’s state of welfare.


AJIL Unbound ◽  
2017 ◽  
Vol 111 ◽  
pp. 272-276
Author(s):  
Jérôme de Hemptinne

In times of war, the first instinct is to relieve the suffering of human beings. Environmental and animal interests are always pushed into the background. However, warfare strongly affects natural resources, including animals, which makes animal issues a matter of great concern. Certain species have been vanishing at a rapid rate because of wars, often with disastrous effects on the food chain and on the ecological balance. Indeed, belligerents rarely take into account the adverse consequences of their military operations on animals. They even take advantage of the chaotic circumstances of war in order to poach protected species and to engage in the trafficking of expensive animal products. While generating billions of dollars each year, such poaching and trafficking allows armed groups to grow and to reinforce their authority over disputed territory. States have also trained, and continue to train, certain animals—principally marine mammals such as bottlenose dolphins and California sea lions—to perform military tasks, like ship and harbor protection, or mine detection and clearance. Millions of horses, mules, donkeys, camels, dogs, and birds are obliged to serve on various fronts (transport, logistics, or communications) and become particularly vulnerable targets.


2021 ◽  
Vol 8 ◽  
Author(s):  
Michael Gilbert Mwango’mbe ◽  
Jane Spilsbury ◽  
Steve Trott ◽  
Judith Nyunja ◽  
Nina Wambiji ◽  
...  

In 2011, several non-governmental and government agencies established the Kenya Marine Mammal Network (KMMN) to provide a platform for the consistent collection of data on marine mammals along the Kenyan coast, identify areas of importance and engage marine users and the general public in marine mammal conservation. Prior to the KMMN, relatively little was known about marine mammals in Kenya, limiting conservation strategies. The KMMN collects data nationwide through dedicated surveys, opportunistic sightings and participative citizen science, currently involving more than 100 contributors. This paper reviews data on sightings and strandings for small cetaceans in Kenya collated by the KMMN. From 2011 to 2019, 792 records of 11 species of small cetaceans were documented. The most frequently reported inshore species were the Indo-Pacific bottlenose dolphin and Indian Ocean humpback dolphin. Offshore species, included killer whales, short-finned pilot whale and long-snouted spinner dolphin. Indo-Pacific bottlenose dolphins, long-snouted spinner dolphins, striped dolphins and Risso’s dolphins were recorded through stranding reports. The efforts of the KMMN were disseminated through international meetings (International Whaling Commission, World Marine Mammal Conference), national status reports, outreach and social media. Data has also supported the identification of three IUCN Important Marine Mammal Areas and one Area of Interest in Kenya. Further research is needed to improve estimates of cetacean abundance and distribution, particularly in unstudied coastal areas, and to assess the extent of anthropogenic threats associated with fisheries, coastal and port development, seismic exercises and unregulated tourism. The expansion of the network should benefit from the participation of remote coastal fishing communities, government research agencies, tourism and seismic operations, among others. The KMMN demonstrated the value of dedicated and citizen science data to enhance marine mammal conservation strategies to boost awareness and eco-tourism and to bring the public and science closer together, promoting research and effective conservation efforts.


PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0251637
Author(s):  
Lauren Kelly Rodriguez ◽  
Amber D. Fandel ◽  
Benjamin R. Colbert ◽  
Jamie C. Testa ◽  
Helen Bailey

Bottlenose dolphins (Tursiops truncatus) are migratory marine mammals that live in both open-ocean and coastal habitats. Although widely studied, little is known about their occurrence patterns in the highly urbanized estuary of the Chesapeake Bay, USA. The goal of this study was to establish the spatial and temporal distribution of bottlenose dolphins throughout this large estuarine system and use statistical modeling techniques to determine how their distribution relates to environmental factors. Three years (April-October 2017–2019) of dolphin sighting reports from a citizen-science database, Chesapeake DolphinWatch, were analyzed. The dolphins had a distinct temporal pattern, most commonly sighted during summer months, peaking in July. This pattern of observed occurrence was confirmed with systematic, passive acoustic detections of dolphin echolocation clicks from local hydrophones. Using spatially-exclusive Generalized Additive Models (GAM), dolphin presence was found to be significantly correlated to spring tidal phase, warm water temperature (24–30°C), and salinities ranging from 6–22 PPT. We were also able to use these GAMs to predict dolphin occurrence in the Bay. These predictions were statistically correlated to the actual number of dolphin sighting reported to Chesapeake DolphinWatch during that time. These models for dolphin presence can be implemented as a predictive tool for species occurrence and inform management of this protected species within the Chesapeake Bay.


PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0242273
Author(s):  
Jean M. Herrman ◽  
Jeanine S. Morey ◽  
Ryan Takeshita ◽  
Sylvain De Guise ◽  
Randall S. Wells ◽  
...  

Age is an important parameter to better understand wildlife populations, and is especially relevant for interpreting data for fecundity, health, and survival assessments. Estimating ages for marine mammals presents a particular challenge due to the environment they inhabit: accessibility is limited and, when temporarily restrained for assessment, the window of opportunity for data collection is relatively short. For wild dolphins, researchers have described a variety of age-determination techniques, but the gold-standard relies upon photo-identification to establish individual observational life histories from birth. However, there are few populations with such long-term data sets, therefore alternative techniques for age estimation are required for individual animals without a known birth period. While there are a variety of methods to estimate ages, each involves some combination of drawbacks, including a lack of precision across all ages, weeks-to-months of analysis time, logistical concerns for field applications, and/or novel techniques still in early development and validation. Here, we describe a non-invasive field technique to determine the age of small cetaceans using periapical dental radiography and subsequent measurement of pulp:tooth area ratios. The technique has been successfully applied for bottlenose dolphins briefly restrained during capture-release heath assessments in various locations in the Gulf of Mexico. Based on our comparisons of dental radiography data to life history ages, the pulp:tooth area ratio method can reliably provide same-day estimates for ages of dolphins up to about 10 years old.


Sign in / Sign up

Export Citation Format

Share Document