Evidence map›Paper›PMID 41862657›Full record

ArticleScientific reports2026

Identification and classification of repeated whistle types from free-ranging rough-toothed dolphins (Steno bredanensis).

Laura Redaelli, Vincent M Janik, Filipe Alves, Julie N Oswald, Marc Fernandez, Eliette Hamard, Laela S Sayigh, Manuel E Dos Santos, Ana Dinis, Francesco Caruso

Abstract read
In one paragraph

Article in Scientific reports, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors.

Laura RedaelliMARE - Marine and Environmental Sciences Centre, ARNET - Aquatic Research Network, Regional Agency for The Development of Research, Technology and Innovation (ARDITI), Funchal, Madeira, Portugal. laura.redaelli@mare.arditi.pt.
Vincent M JanikSea Mammal Research Unit, Scottish Oceans Institute, School of Biology, University of St. Andrews, Fife, UK.
Filipe AlvesMARE - Marine and Environmental Sciences Centre, ARNET - Aquatic Research Network, Regional Agency for The Development of Research, Technology and Innovation (ARDITI), Funchal, Madeira, Portugal.
Julie N OswaldSea Mammal Research Unit, Scottish Oceans Institute, School of Biology, University of St. Andrews, Fife, UK.
Marc FernandezMARE - Marine and Environmental Sciences Centre, ARNET - Aquatic Research Network, Regional Agency for The Development of Research, Technology and Innovation (ARDITI), Funchal, Madeira, Portugal.
Eliette HamardMARE - Marine and Environmental Sciences Centre, ARNET - Aquatic Research Network, Regional Agency for The Development of Research, Technology and Innovation (ARDITI), Funchal, Madeira, Portugal.
Laela S SayighBiology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA.
Manuel E Dos SantosMARE - Marine and Environmental Sciences Centre, ISPA - Instituto Universitário, Lisbon, Portugal.
Ana DinisMARE - Marine and Environmental Sciences Centre, ARNET - Aquatic Research Network, Regional Agency for The Development of Research, Technology and Innovation (ARDITI), Funchal, Madeira, Portugal.
Francesco CarusoDepartment of Marine Animal Conservation and Public Engagement, Stazione Zoologica Anton Dohrn, Naples, Italy.

Funding

Fundação para a Ciência e a Tecnologia 2023.08949.CEECIND/CP2851/CT0001 ((https://doi.org/10.54499/2023.08949.CEECIND/CP2851/CT0001)Fundação para a Ciência e a Tecnologia UI/BD/154079/2022 (https://doi.org/10.54499/UI/BD/154079/2022)Fundação para a Ciência e a Tecnologia UIDB/04292/2020Interreg Atlantic Area EAPA\_0004/2022
6 · The paper itself

Abstract

Acoustic communication is vital for marine mammals. Many delphinids rely on frequency-modulated tonal signals – known as whistles – used during social communication. Among these, individually distinctive “signature whistles” have been extensively studied in bottlenose dolphins (Tursiops truncatus) over the past 60 years. These stereotyped whistles convey individual identity and motivational information. Recent studies have identified similar stereotyped whistles in other delphinids, including a rehabilitated rough-toothed dolphin (Steno bredanensis). However, the function, occurrence, time–frequency characteristics, and degree of stereotypy of whistles in free-ranging individuals of this species remain unexplored. This study analysed acoustic recordings from three encounters with rough-toothed dolphins in summer 2023 off Madeira Island (Eastern North Atlantic). Of 4928 whistles analysed, 1015 were identified as repeated whistles and classified into 25 categories based on frequency modulation contours using visual inspection. Visual classification was verified using an inter-observer reliability test and compared to results from an unsupervised neural network (ARTwarp), employing both sequential and global analyses. The results revealed repeated contour types, with the degree of stereotypy varying across categories and generally lower than that reported for other well-studied delphinid species. Like other delphinids, rough-toothed dolphins exhibit a fission–fusion social structure, where repeated signals may help maintain group cohesion, potentially functioning as individual- or group-level calls. Future research incorporating detailed contextual and behavioral information will be crucial to investigate the function, occurrence and social relevance of repeated calls in rough-toothed dolphin whistle repertoires.

Indexed as

Bottle-Nosed DolphinDolphinsVocalization, AnimalAcousticsAnimalsSocial BehaviorSound SpectrographyStereotyped BehaviorAcousticCommunicationDelphinidMadeira IslandMarine mammalNeural network

Identifiers

PMID41862657
PMCPMC13144356

What OpenQuestion holds

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.