What exactly is going on in this photo? Certainly, it is intriguing scientists as well as people of all kinds who are fascinated by whales and dolphins.
According to the American Museum of Natural History’s Science Bulletin:
Many species interact in the wild, most often as predator and prey. But recent encounters between humpback whales and bottlenose dolphins reveal a playful side to interspecies interaction. In two different locations in Hawaii, scientists watched as dolphins “rode” the heads of whales: the whales lifted the dolphins out of the water, and then the dolphins slid back in. The two species seemed to cooperate in the activity, and neither displayed signs of aggression or distress. Whales and dolphins in Hawaiian waters often interact, but playful social activity such as this is extremely rare between species. These are the first recorded examples of this type of behavior.
Mark Deakos describes two particular interactions in the journal Aquatic Mammals:
Two separate, unusual interactions are described in which a humpback whale (Megaptera novaeangliae) lifted a bottlenose dolphin (Tursiops truncatus) completely out of the water. Both incidents occurred in Hawaiian waters. Based on reports of object play by humpback whales, and the apparent initiation and cooperation of each dolphin being lifted, object (i.e., the dolphin) play by the whale and social play by
the dolphin seem to be the most plausible explanations for the interaction.
Here are more of the photos, all taken from a distance off the shores of Kauai and Maui, Hawaii:
In one observation the scientists noted:
The dolphins positioned themselves directly in front of one humpback still at the surface and appeared to surf the pressure wave created by the whale’s head as it swam. The two dolphins could be differentiated since one of them had a distinctive cookie cutter shark bite on the right side of the body and a notched dorsal fin.
During the next two breaths by the same whale, each dolphin independently was seen lying across the whale’s rostrum as it surfaced, oriented perpendicular to the whale’s body. At 1430 h, the whale stopped and slowly raised its rostrum upward while lifting the well-marked dolphin out of the water. Once completely clear of the water, the dolphin remained arched, on its side, balanced over the end of the whale’s rostrum. The dolphin appeared to cooperate, with no discernible effort to free itself or escape. When the whale was nearly vertical, with its eye nearly breaking the water surface, the dolphin slid down the dorsal side of the rostrum while swinging its flukes upward.
And this is excerpted from the conclusions drawn by the scientists:
Play is considered important in the social and physical development of mammals and birds (Fagen, 1981). However, defining what constitutes play in animals is an ongoing topic of considerable debate (Fagen, 1981; Burghardt, 2005). Burghardt (2005) identified five criteria for characterizing play in animals:
(1) incompletely functional in the context expressed and the behavioral sequence does not produce its usual outcome (e.g., play fighting);
(2) voluntary, pleasurable, or self-rewarding;
(3) different structurally or temporally from related serious behavior systems (behaviors are incomplete, exaggerated, or precocious);
(4) expressed repeatedly during at least some part of an animal’s life span; and
(5) initiated in relatively benign situations (i.e., when the animal is healthy and free from stress or hunger). The behavior of the bottlenose dolphin in each encounter seems to fit all five of these play criteria.
Animal play can be further differentiated into three types:
(1) locomotor play (running, leaping, sliding, and brachiating),
(2) object play (activity directed toward an inanimate object such as manipulating, pulling, pushing, or chewing), and
(3) social play (activity directed toward another living object such as rough and tumble behavior or chasing) (Bekoff & Byers, 1981; Fagen, 1981; Burghardt, 2005).
Social play is play directed at conspecifics or toward other animals taking on the role of proxy for a conspecific (Burghardt, 2005). Burghardt also notes that social play, while generally considered dyadic and reciprocal, can be onesided when it is playful for only one participant (e.g., teasing and harassing).
… The bottlenose dolphin in each encounter appeared to be playing socially and submissively as it allowed the humpback whale to repeatedly lift it out of the water. Submissive social play was documented in two captive bottlenose dolphins that took turns pushing each other around the tank (Kuczaj & Highfill, 2005). Herzing & Johnson (1997) reported interspecific social play by two adult female bottlenose dolphins that propelled two juvenile male Atlantic spotted dolphins (Stenella frontalis) through the water by pushing forward on their tail flukes with their rostra.
In conclusion, these observations suggest that the two encounters described herein were interspecific play by the bottlenose dolphins and humpback whales. The dolphins in both cases seemed in good health and capable of fleeing the humpbacks at any time; therefore, they likely initiated what appeared to be social play with the humpbacks. Reports of object play in humpback whales supports the likelihood that both humpbacks observed lifting the dolphin out of the water were engaged in object (i.e., the dolphin) play.
However, if both participating whales were female, the maternal instinct to lift a small animal resting on its rostrum cannot be ruled out as an alternative explanation. While the bottlenose dolphin and humpback whale regularly associate in Hawaiian waters, this is the first published account of the unique and unusual behavior of a humpback repeatedly lifting bottlenose dolphins out of the water.
For the complete paper, go here.