Standard Presentation Australian Marine Sciences Association Annual Meeting 2023

Sandy bottom contact behaviour of humpback whales   (#282)

Olaf Meynecke 1 2 , Johan Gustafson 2 , Dave Cade 3
  1. Whales and Climate Research Program, Griffith University, Gold Coast, Qld, Australia
  2. Coastal and Marine Research Centre, Griffith University, Gold Coast, QLd, Australia
  3. Stanford University's Hopkins Marine Station, Stanford University, Monterey Bay, USA

Cetaceans are known for their complex behaviours, intelligence and object use. For example, Bowhead whales (Balaena mysticetus) are known to rub on rocks and lateral bottom feeding of humpback whales (Megaptera novaeangliae) has been documented in some populations. Such underwater behaviour is difficult to observe but can play a critical role in the whales’ survival and well-being. Distinguishing between behaviours that are simply playful and those which serve a specific function remains challenging due to a lack of direct observations and detailed descriptions of such behaviors. A CATS (Customized Animal Tracking Solutions) suction cup tag for whales was deployed on 3 different humpback whales to assess their behavior in the Gold Coast bay, Australia. Here, we present first evidence of humpback whales (tagged and untagged individuals) performing bottom contact with prolonged rolling on sandy substrate. In addition, we show that fish were actively feeding from the whales skin during this behaviour. We detail the behaviour and discuss possible drivers, with a focus on cetacean innovation, ectoparasite removal, and importance of fine scale habitat use.