Conference Paper

Is the Bay of Bizerte a school ground for juvenile bottlenose dolphins to learn hunting techniques

Conference: This work reports the unusual distribution of fin whales and its correlated high mortality along the coast of northwestern Mediterranean, in particular in the Pelagos sanctuary in 2007. Of the 20 sightings occurred along the shore, 6 were juveniles unpair


Autumnal visual cetacean monitoring was conducted in the bay of Bizerte (northern
Tunisia) inboard a 4m length boat. Of the 1,000 Km covered by the three months survey
(September to November 2008) a total of 12 sightings were recorded corresponding at least to
75 bottlenose dolphin. All groups were composed by calves more or less 1.5 m length,
manifesting feeding activity. This behaviour adopted using synchronic collaboration in shallow
waters displayed learning techniques for calves. Usually dolphins were divided into small
groups of five to six individuals composed by a mixture of adults and calves. The number of
calves never exceed adults one. They turned around shoal fishes close together in a tight circle,
round them up and dive into the middle to swallow them. Calves follow exactly adult
movements. Sometimes adults kicked fishes with their fluke, launched them into the air and
calves hunted them easily out of water. Due to lack of materials, we haven‟t the opportunity to
make the photo identification protocol, but based on visual sighting with naked eyes, one group
was recognised as seen before one week before using the same feeding techniques.

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Available from: Mehdi Aissi, Oct 01, 2015
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    ABSTRACT: Behavioral scientists have developed methods for sampling behavior in order to reduce observational biases and to facilitate comparisons between studies. A review of 74 cetacean behavioral field studies published from 1989 to 1995 in Marine Mammal Science and The Canadian Journal of Zoology suggests that cetacean researchers have not made optimal use of available methodology. The survey revealed that a large proportion of studies did not use reliable sampling methods. Ad libitum sampling was used most often (59%). When anecdotal studies were excluded, 45% of 53 behavioral studies used ad libitum as the predominant method. Other sampling methods were continuous, onezero, incident, point, sequence, or scan sampling. Recommendations for sampling methods are made, depending on identifiability of animals, group sizes, dive durations, and change in group membership.
    Marine Mammal Science 08/2006; 15(1):102 - 122. DOI:10.1111/j.1748-7692.1999.tb00784.x · 1.94 Impact Factor