Circulation and feeding in blue whales

A study finds extreme ranges of heart rates in blue whales during diving, feeding, and surfacing. Examining the biology of animals at the extremes of body size can reveal the effect of size on physiological function. Blue whales slow their heart rate for deep dives but expend energy to lunge forward and engulf water for filtering and feeding, providing an opportunity to observe the relationship between cardiac function and energetic demand. Jeremy A. Goldbogen and colleagues attached a noninvasive suction cup electrocardiogram to a blue whale and monitored its heart rate during 8.5 hours of diving. Foraging dives lasted as long as 16.5 minutes and reached a maximum depth of 184 m, whereas surface intervals were typically less than 4 minutes. Heart rates during dives reached a minimum of 2 beats per minute, well below the predicted resting heart rate of 15 beats per minute, and surged to 2.5 times the minimum heart rate during lunge feeding. During surface intervals, the heart rate reached 37 beats per minute after very deep dives, near the blue whale’s maximum heart rate, as the whale worked to reoxygenate its tissues. According to the authors, the results show how the circulatory system of whales adapts to accommodate diving and feeding.

Article #19-14273: “Extreme bradycardia and tachycardia in the world’s largest animal,” by Jeremy A. Goldbogen et al.

MEDIA CONTACT: Jeremy A. Goldbogen, Stanford University, Pacific Grove, CA; e-mail:

[email protected]

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