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

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.

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Taxonomy and distribution of bottlenose dolphins (genus Tursiops) in Australian waters: an osteological clarification

Canadian Journal of Zoology ◽

10.1139/cjz-2018-0270 ◽

2020 ◽

Vol 98 (7) ◽

pp. 461-479 ◽

Cited By ~ 1

Author(s):

M. Jedensjö ◽

C.M. Kemper ◽

M. Milella ◽

E.P. Willems ◽

M. Krützen

Keyword(s):

Bottlenose Dolphin ◽

Bottlenose Dolphins ◽

Three Dimensional ◽

Large Sample Size ◽

Type Specimens ◽

Tursiops Aduncus ◽

Common Bottlenose Dolphin ◽

Intermediate Size ◽

The Common ◽

Taxonomic Studies

Species relationships in the bottlenose dolphin (genus Tursiops Gervais, 1855) are controversial. We carried out a comprehensive osteological study of 264 skulls, including type specimens, and 90 postcranial skeletons of Tursiops spp. to address taxonomic uncertainties in Australia using two-dimensional (2D) measurements, and three-dimensional geometric morphometrics (3DGM), tooth and vertebral counts, and categorical data. Analyses provided support for the presence of two forms, aligned to the Indo-Pacific bottlenose dolphin (Tursiops aduncus (Ehrenberg, 1832)) and the common bottlenose dolphin (Tursiops truncatus (Montagu, 1821)), including type specimens. The Burrunan dolphin (Tursiops australis Charlton-Robb, Gershwin, Thompson, Austin, Owen and McKechnie, 2011) fell well within T. truncatus for both 2D and 3DGM methods. Thirteen Tursiops spp. specimens, no T. australis specimens, were of intermediate size (2D) and could not be assigned to either species. For 3DGM data, there was a strong allometric influence and few non-allometric differences between species. Length and width of the cranium and rostrum were important discriminating variables. Tursiops aduncus was smaller, had more teeth, fewer vertebrae, and more erosion on the pterygoids and frontals than T. truncatus. Overall cranium shape was round in T. aduncus and angular in T. truncatus. Skull length of T. aduncus was smaller in low than in high latitudes. This study highlights the importance of large sample size, multiple analytical methods, and extensive geographical coverage when undertaking taxonomic studies.

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Development and Validation of Monoclonal and Polyclonal Antibodies for the Detection of Immunoglobulin G of Bottlenose Dolphins (Tursiops Truncatus)

Journal of Veterinary Diagnostic Investigation ◽

10.1177/104063870701900502 ◽

2007 ◽

Vol 19 (5) ◽

pp. 465-470 ◽

Cited By ~ 12

Author(s):

Hendrik H. Nollens ◽

Linda G. Green ◽

Diane Duke ◽

Michael T. Walsh ◽

Beth Chittick ◽

...

Keyword(s):

Monoclonal Antibodies ◽

Polyclonal Antibody ◽

Immunoglobulin G ◽

Bottlenose Dolphin ◽

Tursiops Truncatus ◽

Bottlenose Dolphins ◽

Enzyme Linked Immunosorbent Assay ◽

Common Bottlenose Dolphin ◽

Circulating Antibodies ◽

The Common

Antibodies directed against species-specific immunoglobulin G (IgG) have a broad range of applications in serologic and immunologic research and in the development of clinical assays. Validated anti-IgG antibodies for marine mammal species are in short supply. The objective of this study was to produce and validate antibodies with specificity for IgG of the common bottlenose dolphin ( Tursiops truncatus). Bottlenose dolphin IgG was purified using protein G. Two mouse monoclonal antibodies and a rabbit polyclonal antibody were developed from mice and rabbits immunized with bottlenose dolphin IgG. The specificity of the monoclonal antibodies and the polyclonal antibody for bottlenose dolphin IgG was first verified by Western blot analysis and enzyme-linked immunosorbent assay (ELISA). For further validation, both monoclonal antibodies and the polyclonal antibody were incorporated in an indirect ELISA for the detection of the immune response of bottlenose dolphins to a vaccine antigen. Three bottlenose dolphins were immunized with a commercial Erysipelothrix rhusiopathiae vaccine, and serial blood samples were collected from all dolphins for measurement of levels of circulating antibodies. Seroconversion was observed in all 3 dolphins by use of both monoclonal antibodies and the polyclonal antibody. Circulating antibodies were detectable as early as 6 days after immunization in 1 dolphin. Peak antibody levels were detected 14 days after the immunization. The ability to detect seroconversion in all 3 immunized bottlenose dolphins firmly establishes the specificity of the monoclonal antibodies and the polyclonal antibody for IgG of the common bottlenose dolphin.

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First estimate of common bottlenose dolphin (Tursiops truncatus) (Cetacea, Delphinidae) abundance off Uruguayan Atlantic coast

Latin American Journal of Aquatic Mammals ◽

10.5597/00223 ◽

2017 ◽

Vol 11 (1-2) ◽

pp. 144-154 ◽

Cited By ~ 5

Author(s):

Paula Laporta ◽

Pedro Fruet ◽

Eduardo Secchi

Keyword(s):

Bottlenose Dolphin ◽

Tursiops Truncatus ◽

Bottlenose Dolphins ◽

Atlantic Coast ◽

Coastal Region ◽

Demographic Stochasticity ◽

Southwest Atlantic ◽

Open Population ◽

Common Bottlenose Dolphin ◽

Population Size Estimates

The common bottlenose dolphin Tursiops truncatus is often observed throughout the oceanic coast of Uruguay. Historically, its distribution was wider, including the estuary of the Río de la Plata, but currently its occurrence seems to be restricted mainly to the Uruguayan Atlantic coast (Rocha Department). Conflicting interests and tradeoffs between conservation and development are being generated in Uruguay. On one hand, the establishment of protected areas, responsible tourism and sustainable fisheries are promoted, while on the other hand, foreign exploitation of natural resources and development of mega-infrastructure in coastal zone are facilitated. In this work, we provide the first estimate of bottlenose dolphin’s abundance along the Uruguayan Atlantic coast. These results can be used as baseline information for monitoring population trends and guiding conservation actions for bottlenose dolphins in Uruguay. Mark-recapture models were applied to data of photoidentified animals with long-lasting natural marks. Total population size estimates of 63 individuals (95% CI = 54–74) and 61 (95% CI = 53–73) were obtained from closed and open population models, respectively. Although the estimates are within the range of values obtained for other coastal bottlenose dolphin populations in the Southwest Atlantic Ocean, as well as other regions of the world, it is lower than the values reported for populations inhabiting open habitats. This small population is probably vulnerable to non-natural removals, environmental and demographic stochasticity. Therefore, precautionary actions are recommended given the planned development for this coastal region.

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

Latin American Journal of Aquatic Mammals ◽

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.

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Genetic divergence and fine scale population structure of the common bottlenose dolphin (Tursiops truncatus, Montagu) found in the Gulf of Guayaquil, Ecuador

PeerJ ◽

10.7717/peerj.4589 ◽

2018 ◽

Vol 6 ◽

pp. e4589 ◽

Cited By ~ 6

Author(s):

Rosa de los Ángeles Bayas-Rea ◽

Fernando Félix ◽

Rommel Montufar

Keyword(s):

Population Structure ◽

Bottlenose Dolphin ◽

Tursiops Truncatus ◽

Bottlenose Dolphins ◽

Western Coast ◽

Common Bottlenose Dolphin ◽

Dolphin Population ◽

The Common ◽

Gulf Of Guayaquil ◽

Outer Estuary

The common bottlenose dolphin, Tursiops truncatus, is widely distributed along the western coast of South America. In Ecuador, a resident population of bottlenose dolphins inhabits the inner estuarine area of the Gulf of Guayaquil located in the southwestern part of the country and is under threat from different human activities in the area. Only one genetic study on South American common bottlenose dolphins has been carried out to date, and understanding genetic variation of wildlife populations, especially species that are identified as threatened, is crucial for defining conservation units and developing appropriate conservation strategies. In order to evaluate the evolutionary link of this population, we assessed the phylogenetic relationships, phylogeographic patterns, and population structure using mitochondrial DNA (mtDNA). The sampling comprised: (i) 31 skin samples collected from free-ranging dolphins at three locations in the Gulf of Guayaquil inner estuary, (ii) 38 samples from stranded dolphins available at the collection of the “Museo de Ballenas de Salinas,” (iii) 549 mtDNA control region (mtDNA CR) sequences from GenBank, and (iv) 66 concatenated sequences from 7-mtDNA regions (12S rRNA, 16S rRNA, NADH dehydrogenase subunit I–II, cytochrome oxidase I and II, cytochrome b, and CR) obtained from mitogenomes available in GenBank. Our analyses indicated population structure between both inner and outer estuary dolphin populations as well as with distinct populations of T. truncatus using mtDNA CR. Moreover, the inner estuary bottlenose dolphin (estuarine bottlenose dolphin) population exhibited lower levels of genetic diversity than the outer estuary dolphin population according to the mtDNA CR. Finally, the estuarine bottlenose dolphin population was genetically distinct from other T. truncatus populations based on mtDNA CR and 7-mtDNA regions. From these results, we suggest that the estuarine bottlenose dolphin population should be considered a distinct lineage. This dolphin population faces a variety of anthropogenic threats in this area; thus, we highlight its fragility and urge authorities to issue prompt management and conservation measures.

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Persistent Effects of Begging on Common Bottlenose Dolphin (Tursiops truncatus) Behavior in an Estuarine Population

Aquatic Mammals ◽

10.1578/am.42.4.2016.531 ◽

2016 ◽

Vol 42 (4) ◽

pp. 531-541 ◽

Cited By ~ 3

Author(s):

Rebeccah A. Hazelkorn ◽

Bruce A. Schulte ◽

Tara M. Cox

Keyword(s):

Bottlenose Dolphin ◽

Tursiops Truncatus ◽

Common Bottlenose Dolphin

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Involution and Cystic Transformation of the Thymus in the Bottlenose Dolphin, Tursiops truncatus

Veterinary Pathology ◽

10.1177/030098589403100603 ◽

1994 ◽

Vol 31 (6) ◽

pp. 648-653 ◽

Cited By ~ 23

Author(s):

D. F. Cowan

Keyword(s):

Body Size ◽

Bottlenose Dolphin ◽

Tursiops Truncatus ◽

Squamous Epithelium ◽

Gulf Coast ◽

Bottlenose Dolphins ◽

Adult Life ◽

Lymphoid Cells ◽

Texas Gulf Coast ◽

Thymic Cysts

The thymus glands of 10 bottlenose dolphins, Tursiops truncatus, collected along the Texas Gulf coast were examined using standard histologic and immunocytochemical methods. The thymus gland of Tursiops persists into adult life, represented by medulla and progressively thinning cortex. A network of epithelial cells, including Hassal bodies, is demonstrable using polyclonal anti-cytokeratin antibody. The network condenses, with loss of lymphoid cells as involution progresses. Cysts arise within the condensed network. These cysts, found in eight of 10 animals, increase in number and size with increasing body size. Body size tends to reflect age. Thymic cysts typically have an irregular shape when small but tend to become spherical as they enlarge. Theey may be lined by squamous epithelium of variable thickness. Eventually, the cysts become macroscopic and filled with a colloidlike material and may largely replace the thymus, which may be identified by noncystic remnants adjacent to the cysts.

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Long-term monitoring for the surveillance of the conservation status of Tursiops truncatus in an EU Natura2000 site in the Mediterranean Sea. A pilot study in the Tuscan Archipelago

Mediterranean Marine Science ◽

10.12681/mms.24562 ◽

2021 ◽

Author(s):

ANTONELLA ARCANGELI ◽

ROBERTO CROSTI ◽

ILARIA CAMPANA ◽

LARA CAROSSO ◽

MARTINA GREGORIETTI ◽

...

Keyword(s):

Pilot Study ◽

Mediterranean Sea ◽

Bottlenose Dolphin ◽

Tursiops Truncatus ◽

Conservation Status ◽

Natura 2000 ◽

Research Network ◽

Habitats Directive ◽

Common Bottlenose Dolphin ◽

The Mediterranean

A pilot study, using the dataset from the research network ‘FLT Med Net’, which regularly monitors transborder regions in the Mediterranean Sea using ferries as platform for systematic surveys, was undertaken to assess common bottlenose dolphin range and population trends within the Natura 2000 EU marine site “Tutela del Tursiops truncatus”. The site was recently designated by the Tuscany Region (Italy) within the requirement of the EU Habitats Directive. In order to evaluate the conservation status of bottlenose dolphin according to the surveillance scheme of the Directive, two six-year periods (2007-2012; 2013-2018) were compared to assess trends in distribution-occurrence (range); Sightings Per Unit of Effort and Density (population). In total, 18146 NM were surveyed along two fixed transects, recording 90 sightings of Tursiops truncatus and a total of 268 specimens. Between the two periods, slight but not statistically significant differences were assessed, with decreasing trend in range and population of the species; no variation was detected in mean group sizes. Travelling was the most common behaviour, and juveniles were present in 20% of the sightings, concentrated during spring and summer. The consistent FLT Med Net dataset was found to be appropriate to evaluate important parameters for the assessment of trends in the conservation status of Tursiops truncatus at the Natura2000 site scale.

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