White-beaked dolphins have been a focus species of our research since 2007, just like the humpback whales and minke whales. We mainly collect our data for them in Faxaflói, Reykjavík, but whenever they surprise us up in the northern Eyjafjörður of Akureyri, we also collect as much data as possible. But that is not always easy, as the white-beaked dolphins can be so fast in their movements that getting a photo of their dorsal fin at the right angle and at the right time requires quite a bit of practice.
The white-beaked dolphins (Lagenorhynchus albirostris) get their name simply from their appearance. They have a beautiful colouration pattern with a white belly colouration that extends to their face, making it appear like they have a white “beak”. Younger individuals sometimes lack this feature, but their colouration changes as they get older and then most of them acquire this distinctive characteristic. They are amongst the larger of the dolphin species, with a length of up to 3 meters and weighing up to 350 kg. This is not just beneficial, it is necessary for survival in sub-arctic waters like we have here in Iceland. A bigger body can produce more body heat and also have a thicker layer of blubber ( this is what the fat of cetaceans is called ) to isolate their inner body organs from the cold surrounding waters. Their diet consists of a variety of fish, even squid and stingray. They are not very picky eaters and excellent, very quick and agile hunters.
When we encounter white-beaked dolphins on our tours, we never know which one of their many behaviours to expect. They can be anything from elusive or resting to extremely playful and interactive with our boats. When they show off their jumping skills it becomes clear how strong they are as they can jump very high out of the water and this numerous times in a row! They also enjoy bow-riding of surfing in the wake of the boat which is as much fun for them as it is for us to watch. And as they are endemic to Icelandic waters, they can be seen all year round and even reproduce and give birth here. Seeing calves is an amazing experience and also the best sign any scientist/ conservationist could hope for, as it means the population is feeling well, comfortable and healthy.
Seeing the white-beaked dolphins is always something to consider as very special, because their distribution is only in the northern parts of the North Atlantic and Iceland can be considered the best country to see them!
White-beaked dolphins acquire nicks and notches, which are parts missing out of their dorsal fins, throughout their live. Alongside with these come scars, different pigmentations or even malformations. All these are visual features that are unique to each individual and help us identify them simply through taking photos whenever we encounter them.
Nicks and notches can have numerous causes: interactions with other dolphins, for example. Even when playing, they can be quite rough with one another, not hesitating to use their teeth on each other. That is also how scars which we call tooth rakes, happen.
These could of course also have a more aggressive nature. Other pods or other species of dolphins, like the Orca, the world's largest dolphin species, may fight the white-beaked dolphins when they are in their hunting area. As dolphins do not have claws, they simply use their teeth and bite each other, aside from using their strong tails at times, when these kind of food competition fights happen.
Sadly, nicks and notches can also have anthropogenic ( human induced ) causes. Mainly these are entanglements in fishing gear, boat propeller strikes or boat collisions. Through numerous studies around the world, scientists have been able to link certain patterns of nicks and notches to certain causes. For example if there is one nick on either side of the dorsal fin and they are opposing each other it most likely was caused by a fishing line wrapped around the fin. By being able to make these links, it is even possible to see how much, or how little, dolphins are influenced by human actions.
Nicks and notches are not only valuable to tell us about the life history of a dolphin, but also to identify it. As described before, they are unique to each individual and stay over their lifetime, thus serving us like a fingerprint. In our research, we have created catalogues for all identifiable white-beaked dolphins, so ones that actually have nicks and notches, we have taken photos of since 2007. Using these and comparing photos we are taking on current tours, we can, for example count how often we have seen certain individuals. This can be great fun, as it clearly shows some dolphins just love our boats and seem to even seek us out if they hear our boats engines from far away.
Since 2007 we have recorded a total of 471 white-beaked dolphins in our catalogue. These have been identified from 2007 until April 2018 and we are eagerly working to get to the rest of our collected data and process it, as surely we will find quite a few new dolphins within that data.
Some examples of these dolphins are Large Nick, Puzzle, Sophie and Ventiquattro.
Ventiquattro is a dolphin we know since the beginning of our research on 2007 and we have seen him nearly every year since. In 2012, Puzzle joined our data base and was given this name due to the shape of the nick in the upper part of its dorsal fin resembling a hole for a puzzle piece. Large Nick we know since 2012 and this dolphin simply seems to love the bay, as it is around very often, no matter if summer or winter. It is similar with Sophie, whom we have known since 2013. This dolphins dorsal fin is so distinctive, many of us at Elding recognise it at first sight.
All four of them have already been seen on several tours this summer season! And we hope to see them on many more. If you have already come out on a tour with us, or you are still planning to, why not see if you recognise one of them?!
Article by head research coordinator Sabrina Voswinkel