scholarly journals Preliminary Evaluation of Potential Impacts Associated with Small Cetacean Remote Biopsy Sampling by Controlled Testing on Stranded Common Bottlenose Dolphins (Tursiops truncatus)

2021 ◽  
Vol 2 (4) ◽  
pp. 544-558
Author(s):  
Errol I. Ronje ◽  
Casey Brechtel
Keyword(s):  
Tursiops Truncatus ◽  
Bottlenose Dolphins ◽  
The Body ◽  
Preliminary Evaluation ◽  
Target Area ◽  
Sample Length ◽  
Adult Age ◽  
The Individual ◽  
Tools And Techniques ◽  
Body Condition Scores

To explore the potential macroscopic tissue effects of select remote biopsy tools to common bottlenose dolphins (Tursiops truncatus), carcasses were darted and their traumatic effects on the anatomy in target and non-target areas of the body were described. In total, 87 samples were collected (target area, n = 19; non-target area, n = 68) within standardized grid partitions from five carcasses of sub-adult to adult age classes with a range of body condition scores. We broadly classified impacts penetrating completely through the blubber into muscle or deeper internal tissues as over-penetrations (n = 51/87, 59%). For samples collected in the defined target area, there was a low number of over-penetrations (n = 5/51; 10%). However, for samples collected in the defined, non-target areas, a much higher number of over-penetrations occurred (n = 45/51 88%). A visual examination of some samples indicated that sample length and appearance may not be reliable guides to assess the penetration depth of the wounds. These preliminary results suggest samples collected in non-targeted areas could pose much higher risk to the individual. We encourage other researchers considering the use of remote biopsy tools to conduct similar assessments prior to field sampling to better understand the potential consequences of misplaced samples with a view towards continually improving remote biopsy tools and techniques for the benefit of cetacean welfare.

scholarly journals POWER OUTPUT AND PROPULSIVE EFFICIENCY OF SWIMMING BOTTLENOSE DOLPHINS (TURSIOPS TRUNCATUS)

1993 ◽  
Vol 185 (1) ◽  
pp. 179-193 ◽  
Author(s):  
F. E. Fish
Keyword(s):  
Power Output ◽  
Tursiops Truncatus ◽  
High Performance ◽  
Bottlenose Dolphins ◽  
The Body ◽  
Hydrodynamic Performance ◽  
Propulsive Efficiency ◽  
Velocity Amplitude ◽  
Swimming Depth ◽  
Maximum Angle

The power output and propulsive efficiency of swimming bottlenose dolphins (Tursiops truncatus) were determined from a hydromechanical model. The propulsive movements were filmed as dolphins swam in large pools. Dolphins swam at velocities of 1.2-6.0 m s-1. Propulsion was provided by dorsoventral oscillations of the posterior body and flukes. The maximum angle of attack of the flukes showed a linear decrease with velocity, whereas the frequency of the propulsive cycle increased linearly with increasing velocity. Amplitude was 20 % of body length and remained constant with velocity. Propulsive efficiency was 0.81. The thrust power computed was within physiological limits. After correction for effects due to swimming depth, the coefficient of drag was found to be 3.2 times higher than the theoretical minimum assuming turbulent boundary conditions. The motions of the body and flukes are primarily responsible for the increased drag. This analysis supports other studies that indicate that bottlenose dolphins, although well adapted for efficient high- performance swimming, show no unusual hydrodynamic performance.

scholarly journals Bottlenose dolphins (Tursiops truncatus, Montagu 1821) in central-northern coast of Rio de Janeiro State, Brazil: stranding patterns and insights into feeding habits

10.5597/00228 ◽  
2017 ◽  
Vol 11 (1-2) ◽  
pp. 191-198 ◽  
Author(s):  
Jailson Moura ◽  
Davi Castro Tavares ◽  
Helio K.C. Secco ◽  
Salvatore Siciliano
Keyword(s):  
Body Length ◽  
Bottlenose Dolphin ◽  
Tursiops Truncatus ◽  
Rio De Janeiro ◽  
Prey Species ◽  
Bottlenose Dolphins ◽  
Stomach Contents ◽  
The Body ◽  
Northern Coast ◽  
Janeiro State

The bottlenose dolphin (Tursiops truncatus) may be one of the best known dolphin species worldwide, principally due to its coastal distribution in many regions. However, few studies about ecology, biology and threats have been conducted on the Brazilian coast. The aim of the present work is to analyze the stranding pattern and stomach contents of bottlenose dolphins in the central-north coast of the Rio de Janeiro State, from Saquarema to São Francisco de Itabapoana (~300km of coast line). Forty nine stranding events were recorded through regular beach surveys from 1999 to 2012 and also through access to previous published studies conducted since 1984. The strandings were distributed throughout the study area, but there was a trend of occurrence in the extreme southern and northern regions. Nine specimens showed evidence of accidental mortality in fishing nets. The strandings were more frequently recorded during autumn and winter (χ2; p < 0.05). Male bottlenose dolphins stranded more often than females, showing significant differences in this relationship (χ2; p < 0.05). Most stranded dolphins were classified as adults (> 230cm of body length) (χ2; p < 0.05). The body length varied from 106 to 335cm. Four prey species were found in the stomach contents from the three specimens of bottlenose dolphin analyzed. The most representative prey species was the cutlassfish (Trichiurus lepturus). This study showed that bottlenose dolphins are frequently found dead along the Rio de Janeiro State where they feed mainly on coastal fish. Future studies need to be conducted to improve the knowledge on this poorly known cetacean in Brazil.

scholarly journals Cranial Morphometrics of a Stranded Common Bottlenose Dolphin Tursiops truncatus (Montagu, 1821) in Mersin Bay (Northeastern Mediterranean, Turkey)

2020 ◽  
Vol 8 (1) ◽  
pp. 59
Author(s):  
Deniz Ayas ◽  
Deniz Ergüden ◽  
Nuray Çiftçi ◽  
Mustafa Dogangün ◽  
Hasan Deniz Akbora ◽  
...  
Keyword(s):  
Bottlenose Dolphin ◽  
Tursiops Truncatus ◽  
Bottlenose Dolphins ◽  
National Level ◽  
Young Male ◽  
Marine Species ◽  
Mediterranean Coast ◽  
Common Bottlenose Dolphin ◽  
The Individual ◽  
Taxonomic Studies

On 10 November 2017, a young male common bottlenose dolphin Tursiops truncatus (Montagu, 1821), 185 cm in total length (TL), was found dead on the Mersin Marina (36°46'065"N, 34°34'212"E) in Northeastern Mediterranean coast of Turkey. Measurements of the sample performed and documented. The specimen buried to obtain the skeleton of the individual. At the end of this process, the sample was deposited in the Museum of the Systematic, Faculty of Fisheries, Mersin University, (Catalogue no: MEUMC-17- 11-001). The morphometric measurements can contribute to ongoing fisheries biology and taxonomic studies of T. truncatus from Mediterranean Sea waters. During routine fishing activities, common bottlenose dolphins can be caught in fishing nets and drowned. This issue leads to an extra population loss in addition to environmental factors that cause dolphin deaths. At the national level, measures should be implemented to protect dolphins and other marine species caught off -target.

scholarly journals Ultrasonographic imaging of the reproductive organs of the female bottlenose dolphin, Tursiops truncatus aduncas

Reproduction ◽  
2001 ◽  
pp. 419-428 ◽  
Author(s):  
FM Brook
Keyword(s):  
Tursiops Truncatus ◽  
Reproductive Tract ◽  
Bottlenose Dolphins ◽  
Reproductive Organs ◽  
The Body ◽  
Corpora Lutea ◽  
Age Related ◽  
Close Relationship ◽  
Poorly Differentiated ◽  
Reproductive Events

Routine ultrasonographic examination of the reproductive tract was performed for periods of up to 10 years in ten female bottlenose dolphins (Tursiops truncatus aduncas) in Hong Kong. The ovaries could be reliably and repeatedly identified, lying close to the body surface, in the angle formed by the rectus abdominus and hypaxialis lumborum muscles, and were most easily located by scanning in the transverse plane from the proximal end of the genital slit towards the head. The ovaries are ovoid, with a relatively hypoechoic cortex around a central echogenic mesovarium. The echogenicity of the ovarian parenchyma appeared to increase with increasing age. This may be the result of age-related changes, such as increased fat deposition or fibrosis, or of ovarian 'scars' from multiple ovulations. Small antral follicles, developing follicles and corpora lutea can be identified within the ovarian cortex. Owing to its shape and lack of a definitive border, plus the close relationship to the intestines, the contents of which may obstruct the ultrasound beam, the non-pregnant uterus was not so easily visualized. The endometrium was poorly differentiated and difficult to see. To date, examination of the uterus using ultrasonography has provided little information about endometrial changes during the ovarian cycle in this group of dolphins. Real-time diagnostic ultrasonography provides a means to image the morphology of the reproductive organs in live female dolphins directly and provides a valuable means of assessing reproductive events in this species.

scholarly journals Responses to Familiar and Unfamiliar Humans by Belugas (Delphinapterus leucas), Bottlenose Dolphins (Tursiops truncatus), & Pacific White-Sided Dolphins (Lagenorhynchus obliquidens): A Replication and Extension

2016 ◽  
Vol 29 ◽  
Author(s):  
Heather M. Hill ◽  
Deirdre Yeater ◽  
Sarah Gallup ◽  
Sara Guarino ◽  
Steve Lacy ◽  
...  
Keyword(s):  
Visual Processing ◽  
Tursiops Truncatus ◽  
Bottlenose Dolphins ◽  
Individual Variability ◽  
Activity Level ◽  
Delphinapterus Leucas ◽  
Individual Level ◽  
Video Recordings ◽  
Lagenorhynchus Obliquidens ◽  
The Individual

Previous research has documented that cetaceans can discriminate between humans, but the process used to categorize humans still remains unclear. The goal of the present study was to replicate and extend previous work on the discrimination between familiar and unfamiliar humans by three species of cetaceans. The current study manipulated the familiarity and activity level of humans presented to 12 belugas (Delphinapterus leucas) housed between two facilities, five bottlenose dolphins (Tursiops truncatus), and six Pacific white-sided dolphins (Lagenorhynchus obliquidens) during free-swim conditions. Two measures of discrimination were coded from video recordings of each trial: lateralized visual processing and gaze duration. No clear lateralization effects emerged at the species level, primarily due to extensive individual variability. The results also indicated that activity level influenced gaze durations across species, and for some individuals, the interaction between human familiarity and activity level influenced gaze durations and eye preferences. Unexpectedly, bottlenose dolphins had longer gaze durations for familiar humans whereas belugas and Pacific white-sided dolphins had longer gaze durations for unfamiliar humans. All three groups displayed longer gaze durations for active humans as compared to neutral humans, and belugas and bottlenose dolphins had significantly longer gaze durations than Pacific white-sided dolphins. These results indicate that the cetaceans can discriminate between unfamiliar and familiar humans and preferred active humans. However, discrimination of humans via lateralized visual processing did not appear at the group level, but rather at the individual level which countered previous research. This study is discussed within the contexts of attention and individual differences across animals of different species.

scholarly journals Tough life: the case of a young coastal common bottlenose dolphin repeatedly entangled

10.5597/00243 ◽  
2019 ◽  
Vol 13 (1-2) ◽  
pp. 9-14
Author(s):  
Fernando Félix ◽  
Oscar Vázcones ◽  
Ruby Centeno ◽  
Juan Romero
Keyword(s):  
Bottlenose Dolphin ◽  
Tursiops Truncatus ◽  
Healing Process ◽  
The Body ◽  
Fishing Gear ◽  
Artisanal Fishing ◽  
Common Bottlenose Dolphin ◽  
Gulf Of Guayaquil ◽  
The Individual

We report the case of a young coastal bottlenose dolphin (Tursiops truncatus) hooked and entangled in artisanal fishing gear on two occasions in a period of six months. In both occasions the animal managed to get rid of the gear by itself. The case occurred in the inner estuary of Gulf of Guayaquil, Ecuador. The animal survived both events, but scars remained in various parts of the body and missed fluke tips. Photographs of the individual after the events allowed to evaluate the healing process. This case demonstrated that longlines represents a threat for this population.

scholarly journals Object Manipulation and Play Behaviour in Bottlenose Dolphins (Tursiops truncatus) under Human Care

2017 ◽  
Vol 30 ◽  
Author(s):  
Fabienne Delfour ◽  
Carly Faulkner ◽  
Toby Carter
Keyword(s):  
Bottlenose Dolphin ◽  
Tursiops Truncatus ◽  
Environmental Enrichment ◽  
Bottlenose Dolphins ◽  
The Body ◽  
Body Parts ◽  
Scientific Papers ◽  
Enrichment Program ◽  
Human Care ◽  
Head Area

Cetaceans are well-known to display various play activities: numerous scientific papers have documented this phenomenon in wild populations and for delphinids under human care. The present study describes analyses of bottlenose dolphin (Tursiops truncatus) interactions with man-made objects introduced to their habitat as part of an environmental enrichment program. At Parc Asterix Delphinarium (France), 9 bottlenose dolphins were presented with 21 different objects. During 17 hours and using object-focal follows, we studied the dolphins’ behaviors directed toward the objects, according to the objects physical properties (i.e. complexity and buoyancy). We also documented the body parts the animals used to manipulate the objects. The results show that young dolphins displayed more playful actions towards the introduced objects than their older conspecifics. In general, subjects preferred the objects classified as simple and floating, they displayed a larger variety of behaviours, they spent more time and were more creative with them than with other types of objects. Finally, there was significantly more contact and “manipulation” with the dolphin head area than with the fins, fluke or other body parts. By analyzing the dolphins’ behaviors and actions they directed towards the introduced objects, the present study discusses meanings dolphins might give to their surroundings and the relevance of play behavior to their welfare.

Movements and habitat use of bottlenose dolphins, Tursiops truncatus, in south-eastern Brazil

2020 ◽  
Vol 100 (4) ◽  
pp. 651-662
Author(s):  
Victor Uber Paschoalini ◽  
Marcos César de Oliveira Santos
Keyword(s):  
Habitat Use ◽  
Tursiops Truncatus ◽  
Bottlenose Dolphins ◽  
Eastern Coast ◽  
Brazilian Coast ◽  
Preliminary Evaluation ◽  
The South ◽  
Western Atlantic ◽  
Carbon And Nitrogen ◽  
South Eastern

AbstractBottlenose dolphins (Tursiops truncatus) have been surveyed for at least two decades on the southern Brazilian coast. However, little is known about their distribution and habitat use in lower latitudes of the South-western Atlantic Ocean. Aiming to study the movements and distribution of the species along the south-eastern Brazilian coast, we made a comparison of photo-identified individuals of the species catalogued in 21 cruises conducted between 2012 and 2015. Additionally, we performed stable isotope analyses of carbon and nitrogen in skin samples (N = 35) to provide some insights of dolphin habitat use and trophic ecology through comparisons among individuals of distinct surveyed sectors (northern and southern) and sex. A total of 177 individuals were identified. Re-sightings (N = 24) occurred at intervals from 82 to 979 days at distances from 7 to 179 km. No individual was sighted in both sectors, suggesting spatial segregation. Isotopic comparisons showed no significant differences in carbon and nitrogen signatures between distinct sectors. However, ecological divergences were found when we divided the samples by gender. Wider isotopic niches were found for the northern bottlenose dolphins vs the southern ones, which could be related to temporal and spatial variation in the availability of resources, as well as possible differences in the home ranges of males and females in each region. This study represents a preliminary evaluation of ecological aspects of bottlenose dolphins along the Brazilian south-eastern coast, however, long-term studies on the feeding ecology and habitat use of this species are important to further improve our knowledge.

Evaluation of the video-identification technique applied to bottlenose dolphins (Tursiops truncatus) in Cagarras Archipelago, Rio de Janeiro, Brazil

2008 ◽  
Vol 89 (5) ◽  
pp. 1077-1081 ◽  
Author(s):  
Liliane Lodi ◽  
Luiz Cláudio Mayerhofer ◽  
Cassiano Monteiro Neto
Keyword(s):  
Tursiops Truncatus ◽  
Rio De Janeiro ◽  
Bottlenose Dolphins ◽  
Photo Identification ◽  
Dorsal Fin ◽  
Identification Technique ◽  
The Individual ◽  
Sequential Images ◽  
Reliable Methods ◽  
Video Identification

Reliable methods to identify and monitor cetacean individuals are important to assess population behaviour and ecology. We describe and evaluate the application of the digital video-identification technique (DVI) for the acquisition and analysis of dorsal fin images in the study of bottlenose dolphins (Tursiops truncatus) in the Cagarras Archipelago, Rio de Janeiro, Brazil. Between August and November 2004, we identified and catalogued 20 individuals; 80% were re-sighted more than twice. The Individual Residence Index varied between 1.0 (N = 1) and 0.2 (N = 4). Compared with traditional photo-identification methods, DVI offers significant advantages in respect to production of sequential images and speed of editing and processing.

Influence of stable iodine on the uptake of the thyroid – model vs. experiment

2001 ◽  
Vol 40 (01) ◽  
pp. 31-37 ◽  
Author(s):  
U. Wellner ◽  
E. Voth ◽  
H. Schicha ◽  
K. Weber
Keyword(s):  
Time Course ◽  
Compartment Model ◽  
The Body ◽  
Iodine Uptake ◽  
Model Calculations ◽  
Physiological Conditions ◽  
Iodine Supply ◽  
Predicted Values ◽  
The Individual ◽  
Stable Iodine

Summary Aim: The influence of physiological and pharmacological amounts of iodine on the uptake of radioiodine in the thyroid was examined in a 4-compartment model. This model allows equations to be derived describing the distribution of tracer iodine as a function of time. The aim of the study was to compare the predictions of the model with experimental data. Methods: Five euthyroid persons received stable iodine (200 μg, 10 mg). 1-123-uptake into the thyroid was measured with the Nal (Tl)-detector of a body counter under physiological conditions and after application of each dose of additional iodine. Actual measurements and predicted values were compared, taking into account the individual iodine supply as estimated from the thyroid uptake under physiological conditions and data from the literature. Results: Thyroid iodine uptake decreased from 80% under physiological conditions to 50% in individuals with very low iodine supply (15 μg/d) (n = 2). The uptake calculated from the model was 36%. Iodine uptake into the thyroid did not decrease in individuals with typical iodine supply, i.e. for Cologne 65-85 μg/d (n = 3). After application of 10 mg of stable iodine, uptake into the thyroid decreased in all individuals to about 5%, in accordance with the model calculations. Conclusion: Comparison of theoretical predictions with the measured values demonstrated that the model tested is well suited for describing the time course of iodine distribution and uptake within the body. It can now be used to study aspects of iodine metabolism relevant to the pharmacological administration of iodine which cannot be investigated experimentally in humans for ethical and technical reasons.

Sign in / Sign up

Export Citation Format

Share Document