Archipelagos

  • English
  • Ελληνικα
Who We Are
About UsAbout Us
The TeamThe Team
Research BasesResearch Bases
Research BoatsResearch Boats
Our EquipmentOur Equipment
PartnersPartners
Fields of Action
Marine ConservationMarine Conservation Fisheries Shipping Risks Coraligene & Seagrass Littoral Ecosystems Invasive Species Jellyfish Sea Turtles
Marine MammalsMarine Mammals Dolphins Whales Seals
Terrestrial ConservationTerrestrial Conservation Island Fauna Forests & Flora Freshwater Ecosystems Aegean Seed Bank
Laboratory ResearchLaboratory Research Microplastics Water Analysis Soil Quality
What We Do
Aegean Marine Life Sanctuary
Eco Navigation
Intern Experience
Projects
Videos
Awareness Material
Publications
News
Sea4all Online Educational Platform on Marine Pollution
Sea4all Online Educational Platform on Marine Pollution
he completion of the Mediterranean Symposium on Marine Key Habitats and Non-Indigenous Species, that was organised by UNEP/MAP – SPA RAC
he completion of the Mediterranean Symposium on Marine Key Habitats and Non-Indigenous Species, that was organised by UNEP/MAP – SPA RAC
Happy ending to the rescue of a golden jackal!
Happy ending to the rescue of a golden jackal!
OPEN CALL: for memorable stories of Greek children, aged 6-16, taking action for environmental change!
OPEN CALL: for memorable stories of Greek children, aged 6-16, taking action for environmental change!
View All...
Join Us
Traineeships & Internships
FAQ
Field Courses
Contact
Donate
Menu

Common Dolphin (D. delphis) Bioacoustics Project, Winter 2018

Common Dolphin (D. delphis) Bioacoustics Project, Winter 2018

by Kleopatra Delaveri / Thursday, 15 March 2018 / Published in Marine Conservation Team, Work Journal

Common dolphin (D. delphis) bioacoustics project – a study about vocalization and sociality of the common dolphin population in the Aegean Sea, February-March 2018.

Figure 1 – Common dolphin (Delphinus delphis).

Common dolphins often live in pods consisting of around 12-20 individuals in the Mediterranean Sea (Murphy et al., 2008). The population of this particular species has been declining at an alarming rate in the Mediterranean Sea. Common dolphins get benefits from living in large groups including things such as aid in finding food, defense against predators and access to reproductive members (Evans, 1987). Because of this behavioural tendency towards group dependency and sociality, obtaining Common dolphin bioacoustics recordings is more feasible than when working with a more reclusive species (Roch et al., 2007). Common dolphins produce a number of vocalizations, including whistles, clicks, and burst pulse calls, some of which can be used to identify an individual  (Soldevilla et al., 2008).

OBJECTIVES

The purpose of this study is to explore the vocal repertoire of the Common dolphin in the eastern Aegean Sea. The objectives set for this project are:

  • record common dolphins vocalizations, including whistles, clicks, and burst pulse calls;
  • measure certain parameters for each individual whistle recorded;
  • classify recorded whistles according to shape and contour;
  • compare whistle characteristics to the behaviour assumed by individuals during the sighting;
  • use whistles to identify individuals and pairing with photo-ID for better identification

METHODS

For each recording, the Marine Mammal Bioacoustics Team will classify the types of vocalizations: whistles with and without harmonics, clicks and pulsed calls (Figure 2). In order to gather this data an AS-1 Aquarian hydrophone is used to record sound data. Raven software is then used to analyze the recorded data.

 

The whistle parameters that will be measured by the Team include: duration, start frequency, end frequency, minimum frequency, maximum frequency and more. Whistle shape and contour used can be found in the chart below (Figure 3).

Figure 3 Constant frequency (A); upsweep (B); downsweep (C); convex (D); concave (E); sine (F). Each general contour classification represents the overall whistle contour while the minor contour classifications, or subcategories, considered frequency modulations at the beginning (2), at the end (3), at both ends (4) of the whistle or no modulation at all (1) (Ansmann et al., 2007). F4-F8 are examples of signature whistles.

Figure 2 – Spectrograms of common dolphin vocalizations: distinct individual whistles with no harmonics (A); whistles with harmonics that are still individually distinct from each other (B); overlapped whistle bouts, with whistles that cannot to be uniquely identified (C and D). Clicks are also visible as vertical lines in (A), (C), and (D), and pulsed calls are visible in (D) (Henderson et al., 2012).

RESULTS

Whistle parameters change with the animal’s behaviour, an example of social situation adaptation in the vocal repertoire of common dolphins. Outside of behaviour, Recordings can also give insight to individual identifications, as signature whistles can be used alongside Photo-ID. The Marine Mammal Bioacoustics Team will compare the shape of the whistles with the behaviour of the dolphins at that time in order to understand if there is a relationship between shape and behaviour also in Aegean Common dolphin population as well as to identify individuals among the populations found in the Aegean Sea.

 

Chelsea Gragg
M.A. Anthrozoology
University of Exeter
England

Simone Antichi
Masters in Marine Biology,
Marche Polytechnic University
Italy

0
0
0
0
0

What you can read next

Ocean acidification effects on Venus casina shells: A Preliminary Experimental Project, Summer 2017
Marine Mammals, July 2017
Herpetofauna monitoring in the south-east of Samos Island, Fall 2018

Recent Posts

  • Sea4all Online Educational Platform on Marine Pollution

    Sea4all Online Educational Platform on Marine Pollution

    14 February 2019
    This morning, a working group meeting was launched in Arad, …
  • he completion of the Mediterranean Symposium on Marine Key Habitats and Non-Indigenous Species, that was organised by UNEP/MAP – SPA RAC

    he completion of the Mediterranean Symposium on Marine Key Habitats and Non-Indigenous Species, that was organised by UNEP/MAP – SPA RAC

    20 January 2019
    The completion of the Mediterranean Symposium on Marine Key Habitats …
  • Happy ending to the rescue of a golden jackal!

    Happy ending to the rescue of a golden jackal!

    18 January 2019
    A juvenile jackal was found on the roadside, in the …
  • OPEN CALL: for memorable stories of Greek children, aged 6-16, taking action for environmental change!

    OPEN CALL: for memorable stories of Greek children, aged 6-16, taking action for environmental change!

    15 January 2019
    One of the biggest broadcasters in Europe, are working in …
  • The “Interactions between Marine Mammals and Fisheries, case studies from the Eastern Aegean and the Levantine Sea”

    The “Interactions between Marine Mammals and Fisheries, case studies from the Eastern Aegean and the Levantine Sea”

    11 January 2019
    The “Interactions between Marine Mammals and Fisheries, case studies from …
  • Ethology of Cetaceans in the Eastern Aegean, Winter 2019

    Ethology of Cetaceans in the Eastern Aegean, Winter 2019

    21 December 2018
    Ethology, the study of animal behavior, is essential for assessing …
  • 35 European Environmental Organizations Demand ‘Clean, healthy and abundant seas by 2020’ from the European Council of Environment Ministers, today the 20th of December 2018 in Brussels.

    35 European Environmental Organizations Demand ‘Clean, healthy and abundant seas by 2020’ from the European Council of Environment Ministers, today the 20th of December 2018 in Brussels.

    20 December 2018
    Clean, healthy and abundant seas by 2020. This is what …
  • enEnglish
  • elΕλληνικα

Subscribe to Our Newsletter

Archipelagos Institute of Marine Conservation is committed to researching and defending the biodiversity of the Greek seas and islands.

Our action is possible only with your help!

donate

Archipelagos - Institute of Marine Conservation © All Rights Reserved

TOP