Boto ( Inia geoffrensis —Cetacea: Iniidae) aggregations in two provisioning sites in the lower Negro River—Amazonas, Brazil: are they related?

PeerJ

article

Waleska Gravena¹  Tomas Hrbek²  Vera Maria Ferreira da Silva³  Izeni Pires Farias² 

[1] Instituto de Saúde e Biotecnologia ,(ISB), Universidade Federal do Amazonas;Laboratório de Evolução e Genética Animal ,(LEGAL), Universidade Federal do Amazonas;Laboratório de Mamíferos Aquáticos ,(LMA), Instituto Nacional de Pesquisas da Amazônia

关键词: River dolphins;    Microsatellite markers;    Sex markers;    Human interactions;   

DOI  :  10.7717/peerj.6692

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

The Negro River currently has seven floating houses where tourists can feed and interact with botos, each with its own history of how these aggregations were formed. Some keepers say these groups are familial, even reporting individuals being born into the group. However, behavioral studies have shown that botos are solitary, only forming groups at feeding areas and during the mating season. In the present study we used 12 microsatellite and molecular sex markers to characterize relationships within and between two boto aggregations (ten and seven botos each) in the lower Negro River. Molecular sexing revealed that all botos sampled from both aggregations were males. This may be explained by habitat preference, as male botos are primarily found in the main channels of large rivers, whereas females prefer more protected areas, such as flooded forests and its channels and lakes. Most of the animals were unrelated within each aggregation, demonstrating that these aggregations are not normally formed due to kinship bonds, but are exclusively for feeding, as botos learn that these places provide easy access to food. This study provides important information that helps us understand how human interaction is affecting the social structure and behavior of these animals.

【 授权许可】

CC BY