Home
IEEE MetroSea 2021
MetroSea2021-S23

Technical Session

2021 IEEE International Workshop on Metrology for the Sea

IEEE MetroSea 2021

CONFERENCE HOME SCHEDULE TRACKS SPONSORS

Special Session LIVE SESSION

Current Challenges and new Technological Approaches Applied to Marine Mammals and Sea Turtles Conservation - PART 2

5 October, 202112:20 - 13:40 CEST

Not Authorized

You don't have privileges to see this content.

Learn more about how to register for an individual account.

GET ACCESS

Please Login

You should be logged in to see this content.

Don't you have an account?
Learn more about how to register for an individual account.

GET ACCESS

PRESENTATIONS
SESSION DETAILS

12:20 - 12:40

Bottlenose dolphins of Montenegro: Abundance Estimation and Residency Patterns

Kenn Papadopoulo - DMAD - Marine Mammals Research Association, France

PRESENTATION

Bottlenose dolphins of Montenegro: Abundance Estimation and Residency Patterns

ABSTRACT

The Bottlenose dolphin (Tursiops truncatus) suffers from the lack of research in the Southern Adriatic Sea. In 2012, a decline of 50% of bottlenose dolphins population in the Mediterranean Sea was reported. To further our understanding of the spatial ecology of bottlenose dolphins in the southern Adriatic Sea, a four-year photo-identification study (starting in 2016) was carried out in Montenegro. Our results showed no permanent residency in Montenegro of any identified individual. Despite the low site fidelity, certain individuals were sighted each year throughout the survey. Key natural habitats for bottlenose dolphins were found all along the Montenegrin coast with notable preferences for Ulcinj, Bar and the Boka Kotorska Bay. Although the lack of data in the previous decade prevented us from inferring population trends, annual abundance estimation revealed a constant decline from 116±17 in 2017 to 79±21 in 2019. Current study provides critical information on the population status of bottlenose dolphins in Montenegro, with a worrying decline recorded between 2016 and 2019 which could be attributed to the natural causes and/or increased human activities in Montenegro, ranging from coastal destruction to oil and gas explorations. Future research has to assess the present threats on the species while following a transboundary approach to understand the home range of species and to investigate the presence of possible habitat shifts.

12:40 -13:00

The decline of common bottlenose dolphin (Tursiops truncatus) presence and group size in Montenegrin waters

Sian McGuinness - DMAD

PRESENTATION

The decline of common bottlenose dolphin (Tursiops truncatus) presence and group size in Montenegrin waters

ABSTRACT

The Mediterranean subpopulation of common bottlenose dolphins (Tursiops truncatus) is classed as vulnerable with a decreasing population trend. Yet, research effort in the Mediterranean varies with relatively little being known of the Southern Adriatic Sea’s bottlenose dolphins, which face increasing numbers of anthropogenic threats, mainly marine traffic, tourism, fishing and seismic activity. To investigate trends in bottlenose dolphin presence, group size and sub-adult presence in Montenegrin waters, 576 land and boat surveys were conducted from September 2016 to August 2020. Chi-squared tests showed a significant decline in bottlenose dolphin presence over the four years. Changes in group size over the four-year period were also assessed using Chi-squared tests, and results showed that in Year 1 (September 2016 to August 2017) significantly more medium (3-4 individuals) and large (over 5 individuals) groups were observed than expected. Whereas, in the following three years more small groups were observed (1-2 individuals). Neither bottlenose dolphin presence nor group size was found to be associated with season. Multinomial logistic regression was used to assess the relationship of sub-adult presence with year, season and group size. Sub-adults were most likely to be present in the summer (June, July and August) and when group size was large. Montenegrin waters are of significant importance to the wider Adriatic. Therefore, urgent action is required to identify the cause of the declining trends and to protect Montenegro’s bottlenose dolphin population from anthropogenic pressures. A dedicated management strategy must be quickly and effectively implemented, while continuous study is required to monitor and assess trends moving forward.

13:00 - 13:20

Impact of cetacean watching vessels on Risso’s dolphins behaviour in the Gulf of Taranto: preliminary information to regulate dolphin watching

Stefano Bellomo - Jonian Dolphin Conservation

PRESENTATION

Impact of cetacean watching vessels on Risso’s dolphins behaviour in the Gulf of Taranto: preliminary information to regulate dolphin watching

ABSTRACT

Dolphin and whale watching has become worldwide a popular ecotourism activity. However, it can itself be a source of disturbance/stress to animals. Therefore, it is necessary quantify its impacts on cetacean species and possible behavioural responses to interaction between vessels and cetaceans. This study provided first preliminary information of the possible impact of a research vessel on behavioural activity of the Risso’s dolphin recorded in the Gulf of Taranto from April 2019 to September 2020. Information about positive, neutral and responses of Risso’s dolphins to research vessel was collected according focal-group protocol with instantaneous scan-sampling during 60 sightings, for a total of 300 sampling sessions of 3-min. Travelling resulted the most observed activity state (62%) followed by resting (24%), socializing (7%) and feeding (7%). A neutral response were observed in 81.3% of cases, a negative one in 17% of cases and positive in 1.7% of cases. For each activity state recorded, the most observed behavioural response was neutral, followed by negative reaction. Results provided in this study seems to indicate that Risso’s dolphins displayed a neutral response in the most of sightings. However, further studies are necessary to better understand if the presence of whale watching vessels may induce changes, and to what degree, in the essential behaviour of this and other species occurring in the area.

13:20 - 13:40

Vessel-based surveys as a tool to fill critical knowledge gap on Grampus griseus in the north-eastern Aegean Sea

Guido Pietroluongo - Università degli Studi di Padova

PRESENTATION

Vessel-based surveys as a tool to fill critical knowledge gap on Grampus griseus in the north-eastern Aegean Sea

ABSTRACT

Data on Risso’s dolphin are very scarce, possibly due to its wide-ranging movements in the Mediterranean basin. Available data suggest the presence of this species in deep waters, shelf-break areas where the slope is steepest, around offshore islands and archipelagos. A total of eight sightings were recorded during vessel-based surveys carried out along opportunistic line transects from March 2017 to October 2019. The results of the monitoring activity showed that the occurrence of this species in the water surrounding Samos Island is unpredictable and that the characteristics of the environment of each sighting are various, as already shown by previous Mediterranean studies. Nonetheless, the results of this study are promising concerning Risso’s dolphin presence and conservation in the waters surrounding Samos Island.

SESSION CHAIRS

Rosalia Maglietta

CNR STIIMA, Italy

e-BADGE

Aylin Akkaya

DMAD-Marine Mammals Research Association, Turkey

e-BADGE

Marta Azzolin

Gaia Research Institute Onlus, Italy

e-BADGE

Giulia Cipriano

University of Bari Aldo Moro, Italy

e-BADGE

DATE & TIME

5 October, 2021
12:20 - 13:40 CEST

SPONSORS

Technical Session

2021 IEEE International Workshop on Metrology for the Sea

IEEE MetroSea 2021

Current Challenges and new Technological Approaches Applied to Marine Mammals and Sea Turtles Conservation - PART 2

Bottlenose dolphins of Montenegro: Abundance Estimation and Residency Patterns

The decline of common bottlenose dolphin (Tursiops truncatus) presence and group size in Montenegrin waters

Impact of cetacean watching vessels on Risso’s dolphins behaviour in the Gulf of Taranto: preliminary information to regulate dolphin watching

Vessel-based surveys as a tool to fill critical knowledge gap on Grampus griseus in the north-eastern Aegean Sea

SESSION CHAIRS

Rosalia Maglietta

Aylin Akkaya

Marta Azzolin

Giulia Cipriano

DATE & TIME

SPONSORS