Interactions Between Humpback Whales (Megaptera novaeangliae) and Dolphins
It is strongly believed that cetaceans, which consist of whales, dolphins, and porpoises, are some of the more intelligent species that exist alongside human beings on this planet. Naturally, due to this high level of intelligence, they are more likely to have interactions with other individuals. These individuals can be members of their own species, or less commonly, members of other species which is even more telling of the cetaceans high intelligence. Most species with a certain level of intelligence will have some kind of interaction and communication between members of their own species, at least between a mother and their child. Although, it takes a significantly higher level of intelligence to have interactions with members of other species. The species of focus for this article is going to be the humpback whale (Megaptera novaeangliae), a large species of baleen whale which can be found in any ocean around the world and from tropical to nearly polar climates. These massive creatures spend the majority of their lives in migration, sometimes traveling over 8000 km in one direction in order to reach their birthing and mating areas (Horton T, et al. 2011).
A humpback whale breaching out of the water, they may do this for a variety of reasons including as a form of communication as well as a form of entertainment. Photo from 2020 – Cape May Whale Watch and Research Center Database
Naturally along these long, arduous journeys the whales are bound to come into contact with various other creatures that live within the ocean, specifically other cetaceans such as dolphins. Interestingly, whales and dolphins have been known to interact with each other in a variety of ways. The seemingly most common interaction between the whales and dolphins is focused around one of the strongest hunting abilities in the world, which is possessed by the dolphins. Dolphins use an organ in their head called the melon, this organ allows them to send out rapid sound waves into the water, when these waves hit something they bounce back and are processed in the lower jaw of the dolphins. These sound waves allow them to produce a mental image in their brain of exactly what and where the things the objects are. This ability allows them to find their prey over very long distances and can disregard abilities like camouflage. The larger baleen whales, such as the humpback, do not have this echolocation ability which means finding their food is much more difficult. Luckily for them, some dolphins and whales consume the same prey items, because of this whales will actually follow the dolphins as they find the bait fish they both eat using echolocation. In return for helping the whales find the food they need to eat, the massive size of the whales moving with the dolphins will usually deter any predators from trying to attack or prey upon the dolphins. This is known as a symbiotic relationship, which means that both parties in the relationship benefit from it. These relationships are not uncommon in nature but this one does show a high level of intelligence. It requires the humpback whale to understand that the dolphins are able to find food better than they are, as well as requiring the dolphins to understand that prey will be intimidated by the size of the whales.
Humpback whale traveling with dolphins, the whales are likely following the dolphins in order to find food but could also just be staying around them for a little while because they enjoy the company. Photo from 2014 – Cape May Whale Watch and Research Center Database
Whales and dolphins will also interact in different ways which are even more unique and even more telling to both of the species’ high intelligence. For example, in Hawaii there have been multiple instances of a humpback whale lifting dolphins out of the water. While this could be seen as an aggressive behavior by the whale this doesn’t seem to be the case. The reason for this is that the dolphins didn’t resist these behaviors in any way, and if anything seemed to enjoy being lifted by the whale. On top of this the whale displayed no other known signs of aggression towards the dolphins and it even seems that the dolphins were the ones initiating this behavior from the whales. It is suspected that this behavior was purely a form of play between the whales and the dolphins given that humpback whales have a history of playing with and lifting objects, while the dolphins are known to play with and socially interact with various marine creatures (Deakos, M et al. 2010).
A humpback whale raising a dolphin out of the water with its head before letting the dolphin slide down its back and into the water. A behavior that was first documented in Hawaii in 2012 and has been seen occasionally since. Photo taken by L. Mazzuca.
-Brenden Gavaghen, Intern at Cape May Whale Watch and Research Center
Stockton University ’21
Deakos, M. H., Branstetter, B. K., Mazzuca, L., Fertl, D., Mobely Jr, J. R. (2010). Two Unusual Interactions Between a Bottlenose Dolphin (Tursiops truncatus) and a Humpback Whale (Megaptera novaeangliae) in Hawaiian Waters. Aquatic Mammals. 36(2), 121-128, DOI 10.1578/AM.36.2.2010.121
Horton, T. W., Holdaway, R. N., Zerbini, A, N., Hauser, N., Garrigue, C., Andriolo, A., Clapham, P. J. (2011). Straight as an arrow: humpback whales swim constant course tracks during long-distance migration. Biol. Lett. 7:674-679. https://doi.org/10.1098/rsbl.2011.0279