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bioRxiv · 10.1101/2022.05.29.493883

Behavior of cetaceans in the waters south of Pico Island (Azores, Portugal) - data obtained during whale-watching 2020

Zahn, P.·Bloechl, A.
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Abstract

Land-based and boat-based surveys were conducted to collect data during whale-watching excursions in July/August and October 2020. Occurrence and behavior of cetaceans south of Pico Island (Azores) were determined. 10 species were sighted. The most frequently sighted species were: Sperm whale (Physeter macrocephalus), Sei whale (Balaenoptera borealis), Atlantic spotted dolphin (Stenella frontalis), Common bottlenose dolphin (Tursiops truncatus), and Rissos dolphin (Grampus griseus). 51 different behaviour patterns were recorded. The majority, 32 behavior, were observed from two or more species. 19 behavioral patterns were observed only once from a single species, Atlantic spotted dolphins showed nine and Sperm whale showed six. The most behavioral patterns were displayed by Stenella frontalis with 26 and Pseudorca crassidens with 22. Interspecific cooperative hunting and intraspecific food sharing were observed, for the latter there were no known observations in the Azores so far.

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Zahn, P., Bloechl, A.. 2022-05-31. Behavior of cetaceans in the waters south of Pico Island (Azores, Portugal) - data obtained during whale-watching 2020. https://doi.org/10.1101/2022.05.29.493883

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