Skip to main content

IMIS

A new integrated search interface will become available in the next phase of marineinfo.org.
For the time being, please use IMIS to search available data

 

[ report an error in this record ]basket (0): add | show Print this page

Residency patterns, abundance, and social composition of Bottlenose Dolphins (Tursiops truncatus) in Bahía San Antonio, Patagonia, Argentina
Vermeulen, E.; Cammareri, A. (2009). Residency patterns, abundance, and social composition of Bottlenose Dolphins (Tursiops truncatus) in Bahía San Antonio, Patagonia, Argentina. Aquat. Mamm. 35(3): 379-386. http://dx.doi.org/10.1578/AM.35.3.2009.378
In: Aquatic Mammals. European Association for Aquatic Mammals: Harderwijk. ISSN 0167-5427; e-ISSN 1996-7292, more
Peer reviewed article  

Available in  Authors 

Keywords
    Tursiops truncatus (Montagu, 1821) [WoRMS]
    Marine/Coastal
Author keywords
    bottlenose dolphins, Tursiops truncatus, photo-identification, residency, abundance, social composition, Patagonia, Argentina

Authors  Top 

Abstract
    Residency patterns, abundance, and social composition of bottlenose dolphins (Tursiops truncatus) were assessed from 2006 to 2008 in Bahía San Antonio (BSA), Patagonia, Argentina. A total of 714 survey hours resulted in 132 contact hours with 224 bottlenose dolphin groups. Results indicated that dolphins can be seen year-round on average every 4 h, with sighting periods lasting an average of 45 min. A total of 57 bottlenose dolphins were positively identified in the bay, of which 56% showed a degree of residency, including almost all mother and calf pairs. Using the closed time heterogeneity model (Mth), and accounting for the proportion of unidentifiable individuals, calculations resulted in a corrected abundance estimate of 83 individuals for the study area. Further analysis revealed that individual dolphins associated at random and that the entire community exhibits rapid disassociations and two levels of casual acquaintances. Data suggest that the shallow waters of BSA support a relatively resident community of bottlenose dolphins, living in a fission-fusion society in which companionships frequently change. The relative constant presence of calves in more than 50% of the dolphin groups and the observed presence of neonates might furthermore indicate that dolphins specifically use this area, among others, to give birth and nurse their young. In addition, a reported decline in bottlenose dolphin sightings in the larger area of the Argentinean coast might indicate that BSA is one of the last remaining refuges of the species in the country. Further research seems vital for their conservation.

All data in the Integrated Marine Information System (IMIS) is subject to the VLIZ privacy policy Top | Authors