It seems like a bucket list item, to go for an idyllic boat ride and see dolphins playing in the wake or riding the bow wave at the front of the boat. But what inspires this behavior in these curious cetaceans? Are they simply enjoying themselves, or is there more to this behavior than meets the eye?
According to the Encyclopaedia of Marine Mammals, dolphins have been bow-riding ever since there were swift boats on the oceans – even the Greeks wrote about bow-riding in the Mediterranean seas. In modern times, it refers to dolphins exploiting the pressure wave caused by the boat at the front of the vessel.
Bottlenose dolphins (Tursiops truncatus) in particular are famous for riding these bow waves and are perhaps the most common species seen when it comes to dolphin-watching tourist activities and boat trips. A 2009 study investigated this species and its encounters with various vessels.
The authors found that between 2003 and 2006, 201 groups of dolphins were encountered, though only 44 showed interactive behaviors with the boats. They suggest that bow-riding might be used to reduce the energetic cost of swimming for the dolphins, though they doubt that it is solely for that purpose and most likely has an element of play.
The study further suggests that factors like the type of vessel, the vessel’s activity, and the engine status are all likely to influence the level of activity and interaction the dolphins had with the boats.
In another study, presented at the 28th Annual Conference of the European Cetacean Society, researchers found that the region of the sea may matter, with dolphins in the Istanbul Strait more likely to bow in the southern entrance to the strait. The authors suggest that the dolphins did this because the area contained more favorable fishing, linking the bow-riding sightings with feeding activities and foraging strategy, though they also suggested an element of play.
Dolphins have been observed not just bow-riding waves caused by boats, but also bow-riding basking sharks (Cetorhinus maximus). Between 2012 and 2019, dolphins were seen interacting with basking sharks on six occasions off the southwest coast of Ireland, and the team recorded 94 bow rides. While there was some suggestion the dolphins could be using this as a kind of mutually beneficial feeding strategy, the more likely reason, the authors suggest, is the dolphins playing.
All of this research indicates multiple reasons why dolphins might bow-ride: it might provide an energetic advantage for a swimming dolphin; help them gain access to preferred feeding grounds; or provide them with more opportunities to hunt prey, as boats may have disturbed the fish in the areas.
However, let’s not forget the element of play. Dolphins are highly intelligent, social, and curious animals, so it may well be they are riding the bow waves just for fun.
Source Link: Why Do Dolphins Swim In Front Of Ships?
