The Indo-Pacific bottlenose dolphin (Tursiops aduncus) in Tañon Strait, central Philippines

published_or_final_versio

Spinner dolphins off tropical East Africa: group dynamics, daily occurrence, and 'unusual' pattern of behaviour

postprintThe Indian Ocean Cetacean Symposium (IOCS 2009), North Malé Atoll, Maldives, 18-20 July 2009

Group size and seasonal pattern of occurrence of humpback dolphins sousa chinensis in Algoa Bay, South Africa

The occurrence of humpback dolphins Sousa chinensis and their group size in Algoa Bay, South Africa, are described for the period May 1991–May 1994. The mean group size of dolphins was seven (ranging between 3 and 24). Group size was not affected by diurnal, tidal or lunar variability. Solitary, large individuals were commonly observed and they occasionally joined groups of other humpback dolphins. The number of sightings of humpback dolphins per unit effort and their group size varied seasonally, increasing in summer and again in late winter. These observations follow a regular seasonal fluctuation in water temperature, coincide with the dolphins’ reproductive seasonal cycle and could be related to seasonal changes in the abundance and distribution of their prey

Indo-Pacific humpback dolphins (Sousa chinensis) in Hong Kong: Modelling demographic parameters with mark-recapture techniques

published_or_final_versio

Increased human occupation and agricultural development accelerates the population contraction of an estuarine delphinid

published_or_final_versio

Echolocation signals of Heaviside's dolphins (Cephalorhynchus heavisidii)

Field recordings of echolocation signals produced by Heaviside's dolphins (Cephalorhynchus heavisidii) were made off the coast of South Africa using a hydrophone array system. The system consisted of three hydrophones and an A-tag (miniature stereo acoustic data-logger). The mean centroid frequency was 125 kHz, with a -3 dB bandwidth of 15 kHz and -10 dB duration of 74 s. The mean back-calculated apparent source level was 173 dB re 1 Pa p.-p.. These characteristics are very similar to those found in other Cephalorhynchus species, and such narrow-band high-frequency echolocation clicks appear to be a defining characteristic of the Cephalorhynchus genus. Click bursts with very short inter-click intervals (up to 2 ms) were also recorded, which produced the cry sound reported in other Cephalorhynchus species. Since inter-click intervals correlated positively to click duration and negatively to bandwidth, Heaviside's dolphins may adjust their click duration and bandwidth based on detection range. The bimodal distribution of the peak frequency and stable bimodal peaks in spectra of individual click suggest a slight asymmetry in the click production mechanism. © 2011 Acoustical Society of America.published_or_final_versio

Threshold of long-term survival of a coastal delphinid in anthropogenically degraded environment: Indo-Pacific humpback dolphins in Pearl River Delta

published_or_final_versio

DISCOVERY: A Photo-Identification Data Management System

Session: Monitoring animals and plantspublished_or_final_versio

How to move around and where to settle: environmental determinants of spatial behaviour in reintroduced lions (Panthera leo)

Session - Predation and Predators: Predator reintroduction in small enclosed reserves and associated prey responsespostprin