scholarly journals Nautical tourism affects common bottlenose dolphin (Tursiops truncatus M.) foraging success in a NATURA 2000 site, North-Eastern Adriatic Sea

2021 ◽  
Author(s):  
DARJA RIBARIC ◽  
JACK CLARKSON
Keyword(s):  
West Coast ◽  
Tursiops Truncatus ◽  
Best Practice ◽  
Bottlenose Dolphins ◽  
Descriptive Analysis ◽  
Natura 2000 ◽  
Common Bottlenose Dolphin ◽  
Key Species ◽  
Natura 2000 Site ◽  
Dolphin Watching

Several studies indicate that unregulated nautical tourism can have negative implications on cetacean behaviour. In recent years, dolphin watching activities (DWA) have increased off the West coast of Istria, Croatia, a region in which the NATURA 2000 site: ‘Akvatorij zapadne Istre’ has been proposed to be designated for bottlenose dolphins (Tursiops truncatus M.). For data collected between 2016 and 2019, we compared dolphin group behaviours from this region during impact (presence of nautical tourism boats (NTBs)) and control (absence of NTBs) scenarios, as well as providing descriptive analysis on the displacement of individuals in the presence of NTBs. Throughout the study years, 48.5 % of NTBs were observed within 15m of the dolphin focal groups and 97 % were observed within 50 m distance. The greatest rates of displacement in dolphin focal groups occurred when NTB numbers were greatest per individual dolphin. Markov chain analysis were used to quantify the short-term effects of NTB presence on dolphin behaviour. In the presence of NTBs, dolphins were more likely to spend time milling and less time foraging. Cumulative behavioural budgets, derived by accounting for the time bottlenose dolphins spent in the presence or absence of NTBs, indicated that vessel exposure levels of 14 % and 25 % were enough to statistically affect milling and foraging behaviours respectively. To lessen the lack of sustainable DWA, the implementation of relevant guidelines, e.g. Global Best Practice Guidance for Responsible Whale and Dolphin Watching (50 m no approach and 300 m caution zone) is therefore crucial to mitigate any long-term consequences the actions of NTBs may have on this key species. To date, 162 bottlenose dolphins have been photo-identified off West coast of Istria and cumulative interference to this population could affect direct ecosystem functioning.

First report on abundance and distribution of common bottlenose dolphins (Tursiops truncatus) in the NATURA 2000 area, Istria, North-eastern Adriatic Sea

2017 ◽  
Vol 98 (5) ◽  
pp. 1039-1053
Author(s):  
Darja Ribarič
Keyword(s):  
Tursiops Truncatus ◽  
Bottlenose Dolphins ◽  
Marine Ecosystem ◽  
Local Population ◽  
Natura 2000 ◽  
The West ◽  
Photo Identification ◽  
Key Species ◽  
North Eastern ◽  
Abundance And Distribution

The bottlenose dolphin (Tursiops truncatus M.) local population off west Istria in the North-eastern Adriatic has received no prior study of abundance and distribution despite the habitat's relevance for the preservation of this key species in the marine ecosystem. The research area comprises part of the NATURA 2000 network which was predominantly established here for these dolphins. Official data regarding the local population's status in the region are currently marked as deficient. Thus, the aim of the present study was to provide the first population data for the area. Boat-based survey work was carried out from April to September 2012–2015 using a mark–recapture photo-identification method. Prior to this period a random data collection was used to study distribution, since 2001, to cover the area of 927 km2 lying between Umag to lighthouse Albanež in the south. 143 bottlenose dolphins were photo-identified to date with the average group size of 9.27 ± 6.53 animals. Several abundance models were used, from which the Markovian robust model proved the best fit and predicted between 47–142 dolphins along the west Istria coast. A few individuals were also identified in Slovenia, indicating a bigger home range along the 98 km length of the studied area. There is an indication of a regular year round presence of dolphins. The west Istria coast constitutes an important feeding and breeding ground. The region should develop a sustainable plan to manage those human activities negatively impacting the dolphins. Therefore the present study is of relevance for the implementation of management directives for their conservation.

scholarly journals 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

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. 

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

2007 ◽  
Vol 19 (5) ◽  
pp. 465-470 ◽  
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.

Consequences of injuries on survival and reproduction of common bottlenose dolphins (Tursiops truncatus) along the west coast of Florida

2008 ◽  
pp. ???-??? ◽  
Author(s):  
Randall S. Wells ◽  
Jason B. Allen ◽  
Suzanne Hofmann ◽  
Kim Bassos-Hull ◽  
Deborah A. Fauquier ◽  
...  
Keyword(s):  
West Coast ◽  
Tursiops Truncatus ◽  
Bottlenose Dolphins ◽  
The West ◽  
Survival And Reproduction

scholarly journals Aspectos etnoecológicos e implicações para a conservação de Tursiops truncatus (Cetartiodactyla: Delphinidae) no Arquipélago das Cagarras, Rio de Janeiro, Brasil

2013 ◽  
Vol 13 ◽  
Author(s):  
Liliane Lodi ◽  
Camilah Antunes Zappes ◽  
Álvaro Samuel Guimarães dos Santos
Keyword(s):  
Tursiops Truncatus ◽  
Rio De Janeiro ◽  
Anthropogenic Impacts ◽  
Participant Observation ◽  
Bottlenose Dolphins ◽  
Morphological Characteristics ◽  
Small Scale ◽  
Common Bottlenose Dolphin ◽  
Significant Difference ◽  
The Common

The objectives of this study were to understand the ecological aspects of the common bottlenose dolphin (Tursiops truncatus) in the Cagarras Archipelago, Rio de Janeiro, Brazil, and possible anthropogenic impacts by comparing the knowledge of local small-scale fishermen (GA) and the regulars in the archipelago (GB). The data obtained were compared with those available in the literature to propose strategies for monitoring and preservation. Between August and December 2010, we applied the methods of participant observation, interviews-questionnaires and use of illustrative posters. Sixty-one interviews were conducted, from which 83.6% were selected by considering correct answers about the identification of the species on posters (morphological characteristics) and description of time of occurrence in the archipelago (July to December) as reported for the species in the literature. Regarding the seven questions analyzed statistically, a significant difference was found between the accounts of the two groups with respect to anthropic threats to T. truncatus. Gill-nets and the decrease of fishing resources were the main causes identified by the GA group whereas the GB group pointed to the disorganized use of space, pollution and predatory fishing as the factors that have threatened the common bottlenose dolphins. The use of ethnobiological data in conservation programs brings opportunities for the collaboration and participation of the community that is directly inserted into the ecosystem as well as a chance for locals to get involved in issues concerning the sustainability of the archipelago.

scholarly journals Differences in the Spatial Structure of Two Pinus cembra L. Populations in the Carpathian Mountains

Forests ◽  
2019 ◽  
Vol 10 (4) ◽  
pp. 326
Author(s):  
Mirela Beloiu ◽  
Carl Beierkuhnlein
Keyword(s):  
Spatial Structure ◽  
National Park ◽  
Pattern Analysis ◽  
Natura 2000 ◽  
Pinus Cembra ◽  
Carpathian Mountains ◽  
Size Classes ◽  
Adult Trees ◽  
Key Species ◽  
Natura 2000 Site

Pinus cembra L. is a key species of high elevation forest ecosystems in Europe. However, in most mountain ranges, its importance has declined considerably. Remnant populations are often isolated and their dynamics and functioning are not well understood. Here, we apply novel approaches in pattern analysis to two P. cembra populations in the Carpathian Mountains in order to identify commonalities and divergences in their spatial structure and dynamics. Four study sites (1.2 ha each) were investigated within the treeline ecotone in two protected areas that differ in terms of protection status. Based on height and diameter, the individuals were classified into three size-classes: sapling, intermediate and adult trees. Spatial distribution and interactions between tree sizes were analyzed using point pattern analysis. The overall structure of all trees was aggregated at a small distance and regular at a greater distance in the population from the Natura 2000 site (p = 0.002), while in the National Park population it was a random pattern. However, the general patterns do not apply to tree size classes and the relationship among them. In the Natura 2000 site, there was no correlation, all the trees were mixed, regardless of their size. In the National Park, the sapling and intermediate were strongly clustered (p = 0.001), but the adult trees were spatially separated from all juveniles, forming patches at a lower elevation. In both areas, spatial patterns indicate the dynamics of the P. cembra population. Whereas in the National Park population, there is evidence of an upward shift, which cannot be confirmed in Natura 2000, where size classes are completely mixed and the dynamic does not translate into an expansion of the population area. The spatial differences between the two populations indicate that conservation strategies need to be developed more individually to support the regeneration of these isolated populations.

scholarly journals Common Bottlenose Dolphin, Tursiops truncatus, Behavioral Response to a Record-Breaking Flood Event in Pensacola Bay, Florida

2021 ◽  
Vol 2 (3) ◽  
pp. 351-369
Author(s):  
Shauna McBride-Kebert ◽  
Christina N. Toms
Keyword(s):  
Tursiops Truncatus ◽  
Bottlenose Dolphins ◽  
Distribution Models ◽  
Density Estimates ◽  
Estuary Mouth ◽  
Low Salinity ◽  
Kernel Density Estimates ◽  
Common Bottlenose Dolphin ◽  
Dolphin Population ◽  
Health Complications

Common bottlenose dolphins, Tursiops truncatus, can suffer health complications from prolonged freshwater exposure; however, little is known about how dolphins behaviorally respond to flood events. We investigated whether dolphins mitigated their freshwater exposure by moving south towards the estuary mouth and/or towards deeper areas with higher salinities in response to a record-breaking flood in Pensacola Bay, Florida. In total, 144 dolphin groups observed during 45 population dynamic surveys were analyzed across two flood-impacted sampling sessions and their respective seasonal control sessions. Kernel density estimates demonstrated southern movement towards the estuary mouth during flood-impacted sessions, but this distribution change was limited. Species distribution models showed that dolphins did not move to deeper areas after the flood and dolphin distribution was not substantially altered by flood-induced salinity changes. The estuary system exhibits strongly stratified waters with broad salinity ranges even during the flood. Dolphins may have mitigated the severity of freshwater exposure by capitalizing on these stratified areas as they continued to use habitat affected by the flood. A lack of avoidance of low salinity could result in this dolphin population being at greater risk for health problems, which should be considered in future population management and conservation.

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

10.5597/00223 ◽  
2017 ◽  
Vol 11 (1-2) ◽  
pp. 144-154 ◽  
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.

scholarly journals New Prey Fishes in Diet of Black Sea Bottlenose Dolphins, Tursiops truncatus (Mammalia, Cetacea)

2014 ◽  
Vol 48 (1) ◽  
pp. 83-92 ◽  
Author(s):  
E. V. Gladilina ◽  
P. E. Gol’din
Keyword(s):  
Black Sea ◽  
Tursiops Truncatus ◽  
Prey Species ◽  
Bottlenose Dolphins ◽  
Population Decline ◽  
Stomach Contents ◽  
Horse Mackerel ◽  
The Black Sea ◽  
Important Prey ◽  
Common Bottlenose Dolphin

Abstract We report 7 new prey fishes in diet of the Black Sea bottlenose dolphins Tursiops truncatus (Montagu, 1821) and the first records of 9 prey items from their stomach contents: herring (Alosa sp.), sand smelt (Atherina sp.), horse mackerel (Trachurus mediterraneus), picarel (Spicara flexuosa), Mediterranean sand eel (Gymnammodytes cicerellus), Atlantic stargazer (Uranoscopus scaber), garfish (Belone belone), gobies (Gobiidae indet.) and blennies (Blenniidae indet.). Th e Atlantic stargazer was recorded as a prey species for the common bottlenose dolphin for the first time. Th e horse mackerel and the picarel, formerly recorded in the diet of Mediterranean bottlenose dolphins, now were frequently found in the examined Black Sea dolphins. Th e list of prey fishes for Black Sea bottlenose dolphins now includes 23 items, with many small pelagic and demersal fishes, and it is similar to that of Mediterranean dolphins. Whiting (Merlangius merlangus) is still an important prey species, as 50-70 years ago, whereas turbot (Psetta maeotica), not recorded by us, could lose its importance due to population decline. As before, red mullet (Mullus barbatus) is recorded in winter feeding. Feeding on mullets (Mugilidae) is not a universal trait, and it is possibly restricted to local geographical areas.

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