To collect information on the animals’ behaviors, Professor Andrew Treitz and his team at the University of British Columbia utilized drone footage and biological data from tags attached to 11 northern and southern resident killer whales in Queen Charlotte Sound, Queen Charlotte Strait, Johnston Strait, and Strait of Juan de Fuca along the British Columbia coast.
Still image from UAV drone video showing data logger placement and breathing. Image credit: McRae et al., doi: 10.1371/journal.pone.0302758.
“Orcas are like sprinters; they lack the endurance for deep and prolonged dives like blue or humpback whales,” Professor Treitz noted.
Research revealed that killer whales predominantly spend their time off the coast of British Columbia, engaging in shallow dives lasting less than a minute.
An adult male recorded the longest dive time of 8.5 minutes.
By determining that the whales took only one breath during the dive, researchers could calculate their oxygen consumption rates per minute for adults and juveniles.
This information contributes to estimating the energy expenditure of killer whales and their daily fish consumption needs.
University of British Columbia student Tess McRae stated, “This will aid in understanding if killer whales, especially the endangered southern population, are obtaining sufficient food. It’s a critical aspect.”
The orcas in the study took 1.2 to 1.3 breaths per minute at rest, increasing to 1.5 to 1.8 breaths per minute while moving or hunting.
For comparison, humans typically take around 15 breaths per minute at rest and 40 to 60 breaths per minute during physical activity.
“It’s akin to holding your breath, rushing to the grocery store, shopping, and returning before being able to breathe again,” explained Dr. Beth Volpoff, a postdoctoral researcher at the University of British Columbia.
Published findings in the online journal PLoS ONE.
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TM McRae et al. 2024. Killer whale breathing rate. PLoS ONE 19 (5): e0302758; doi: 10.1371/journal.pone.0302758
Source: www.sci.news
