Why do sea turtles swim slowly? A metabolic and mechanical approach [RESEARCH ARTICLE]

This study measured the resting metabolic rates and drag coefficients of sea turtles to answer two questions: (1) do turtles swim at the optimal swim speed? and (2) what factors control the optimal swim speed of turtles? The resting metabolic rates of 13 loggerhead and 12 green turtles were measured. Then, the cruising swim speeds of 15 loggerhead and 9 green turtles were measured and their drag coefficients were estimated under natural conditions. The measured cruising swim speeds (0.27–0.50 m s–1) agreed with predicted optimal swim speeds (0.19–0.32 m s–1). The resting metabolic rates of turtles were approximately one-twentieth those of penguins, and the products of the drag coefficient and frontal area of turtles were 8.6 times higher than those of penguins. Therefore, our results suggest that both low resting metabolic rate and high drag coefficient of turtles determine their slow cruising speed.

Source: Journal of Experimental Biology - January 12, 2021 Category: Biology Authors: Kinoshita, C., Fukuoka, T., Narazaki, T., Niizuma, Y., Sato, K. Tags: RESEARCH ARTICLE Source Type: research