{"title":"Spatial segregation and interspecific killing of common dolphins (Delphinus delphis) by bottlenose dolphins (Tursiops truncatus)","authors":"Séverine Methion, Bruno Díaz López","doi":"10.1007/s10211-021-00363-0","DOIUrl":null,"url":null,"abstract":"<div><p>We described the spatial segregation of two species of cetaceans, the common dolphin and the bottlenose dolphin. We also document the first direct observation of interspecific killing of a common dolphin by bottlenose dolphins and of interspecific necrophilia in cetaceans. The study was conducted from 2014 to 2019 in the Ría de Arousa (Northwest Spain). This study highlights that both species use this area as a foraging ground, although they show different patterns of occurrence (bottlenose dolphins were always observed in the ria and common dolphins were mostly observed outside). During the study period, bottlenose dolphins and common dolphins were only observed on five occasions at the same time and in the same area, including three occasions which led to the displacement of the common dolphin(s), and one lethal interaction. In this event, several bottlenose dolphins, including adults and calves, and males and females, aggressively herded, chased, and assaulted a common dolphin. After approximatively 10 min, the common dolphin corpse appeared floating at the surface, and several adult male bottlenose dolphins repeatedly pushed the body underneath the water surface and an (attempted) copulation was witnessed. We suggest that the common dolphin could have been killed for competition for food resources or practice for infanticide, and sexual arousal might have been triggered by expression of dominance. Further information about the occurrence of such behaviors, and the outcomes through specific studies on fitness would be crucial to further understand the implication of such events.</p></div>","PeriodicalId":6879,"journal":{"name":"acta ethologica","volume":null,"pages":null},"PeriodicalIF":1.1000,"publicationDate":"2021-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10211-021-00363-0","citationCount":"6","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"acta ethologica","FirstCategoryId":"99","ListUrlMain":"https://link.springer.com/article/10.1007/s10211-021-00363-0","RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"BEHAVIORAL SCIENCES","Score":null,"Total":0}
引用次数: 6
Abstract
We described the spatial segregation of two species of cetaceans, the common dolphin and the bottlenose dolphin. We also document the first direct observation of interspecific killing of a common dolphin by bottlenose dolphins and of interspecific necrophilia in cetaceans. The study was conducted from 2014 to 2019 in the Ría de Arousa (Northwest Spain). This study highlights that both species use this area as a foraging ground, although they show different patterns of occurrence (bottlenose dolphins were always observed in the ria and common dolphins were mostly observed outside). During the study period, bottlenose dolphins and common dolphins were only observed on five occasions at the same time and in the same area, including three occasions which led to the displacement of the common dolphin(s), and one lethal interaction. In this event, several bottlenose dolphins, including adults and calves, and males and females, aggressively herded, chased, and assaulted a common dolphin. After approximatively 10 min, the common dolphin corpse appeared floating at the surface, and several adult male bottlenose dolphins repeatedly pushed the body underneath the water surface and an (attempted) copulation was witnessed. We suggest that the common dolphin could have been killed for competition for food resources or practice for infanticide, and sexual arousal might have been triggered by expression of dominance. Further information about the occurrence of such behaviors, and the outcomes through specific studies on fitness would be crucial to further understand the implication of such events.
期刊介绍:
acta ethologica publishes empirical and theoretical research papers, short communications, commentaries, reviews and book reviews as well as methods papers in the field of ethology and related disciplines, with a strong concentration on the behavior biology of humans and other animals.
The journal places special emphasis on studies integrating proximate (mechanisms, development) and ultimate (function, evolution) levels in the analysis of behavior. Aspects of particular interest include: adaptive plasticity of behavior, inter-individual and geographic variations in behavior, mechanisms underlying behavior, evolutionary processes and functions of behavior, and many other topics.
acta ethologica is an official journal of ISPA, CRL and the Portuguese Ethological Society (SPE)