Abstract: On 1 September 2003, a school of about 70 pygmy killer whale (Feresa attenuata) of several sizes (lengths varying form 1 to 2.5 m approximately) was sighted. The sighting was made around the La Plata Island (01º 34' S, 80º 99' W), Machalilla National Park, Ecuador, at a depth of about 47 m. The school of dolphins was traveling at a speed of around 30 km/h. During the whole length of the observation, while the animals were traveling, they conducted running leaps and hard splash with their whole bodies outside of the water. On some occasions, their heads were outside of the water and they were bowriding in the waves produced by the boat. Individuals of about one m in length were observed; these were probably calves. We observed the individuals staying close together in the bow area, and the sounds they produced were audible above the water. The length of the whistles was around 5 s. The species was observed at a 3 km distance from the Isla de la Plata and about 33 km from the continental coast of Ecuador.

Key Words: Feresa attenuata, Pygmy killer whale, behavior, Machalilla National Park, Ecuador, Southeast Tropical Pacific

Document Type: Research article

DOI: 10.1578/AM.30.3.2004.441

Page Numbers: 441-444

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