Energetic Effects of Whale-Watching Boats on Humpback Whales on a Breeding Ground

Interactions between whale-watching boats and cetaceans can lead to changes in their behavior. From a management perspective, it is important understand how this type of disturbance be translated into physiological effects, such as energetic metabolism. Humpback whales ( Megaptera novaeangliae ) typically do not feed while breeding grounds, thus they depend on finite energy reserves. The effect the metabolism humpback whales, ground northern Peru (4°10′35″S, 81°08′03″W) was evaluated. Groups were tracked from land, under following scenarios: with, without, before-during-after presence boats. Mass-specific cost transport (COT) used proxy efficiency calculated swimming speed breath frequency estimations. No differences detected frequency, speed, COT when comparing with without However, boats, swim increased, decreased number increased. Exponential increment breathing at higher detected. absence speeds beyond assumed optimal range suggested no shifts metabolic inefficiency. Our results suggest 2 4.05 m/s, representing values 0.020 0.041 J × (kg m) –1 . In light our results, we encourage implementation regulations activity, particularly limiting interacting same group whales.