Pair of Fin whales (finnhval) surfacing in stormy weather. ©George McCallum
One part of Ecosystem survey is to estimate the numbers and species of whales and other marine mammals seen from G.O.Sars during the transects between stations. How do we do this?
Two observers are on the bridge, one watching the port side, the other watching the starboard side. Each has an angle board and a microphone which is connected to a laptop computer. When they see a whale, they key the microphone and read in the relative angle to the whale as well as estimating the distance to the animal in metres. When they key the microphone, the laptop computer automatically records the exact time and position of the ship via GPS and also records the details and data read into the microphone. The observers search for whales using only their eyes - binoculars are only used to identify which species of whale if the sighting is distant.
The weather plays an important part for the whale observers, the better the weather, the easier it is to spot and identify the animals seen. Minke whales for example are very difficult to spot in anything above Beaufort 4, whilst larger baleen whales can be spotted in weather and wind up to Beaufort 6 to 7.
ID photograph of humpback whale tail showing markings on underside. ©George McCallum.
Pair of white beaked dolphins (kvitnos). ©George McCallum.
What have we seen so far?
The first days of the survey had good weather and we spotted over 20 Sperm whales as we travelled up the continental shelf as well as 3 minke whales. Since then the weather has´nt been too great for spotting whales, with winds between Beaufort 5-7 and with many thick fogbanks on other days. However, we still have managed to see various groups of white beaked dolphins, some minkies and on the 11th of August, we passed numbers of fin and humpback whales that were feeding on lodde in a concentrated area. We also saw a very rare sight, a breaching Fin whale about 700m from the ship - unfortunately the camera was about 10 feet away at the time and the Fin only jumped the once - better luck next time.
G.O.Sars is heading east now and the weather is good so we hope to be able to report many more whale sightings in the coming weeks.
Another part of the whale observers job is to try and take photo identification images of certain whale species if they are close enough to the ship. For example, when Humpback whales dive, they usually lift their tails above the surface, enabling us to photgraph the underside of the tail. The various marks, pigmentation and scars on the tail form a unique pattern enabling us to identify indivual whales, it´s very similar to fingerprints in humans - no two tails are exactly the same, just like no two fingerprints are the same. The IMR has been photographing Humpback whale tails for many years now and has built up a catalogue of many "whale tail " images. Some of these animals have been photographed many times in the last years, one has been seen in the Bjornoya area for almost 17 years now. There has also been a match between a humpback photographed near Bjornoya with a humpback photographed in the caribbean sea many thousands of kilometres away at a different time, showing that at least some of "our" Bjornoya whales migrate between both areas. Other whales such as Blue whales, Killer whales and Sperm whales can also be tracked over the years using this photographic method.
Written by George McCollum, whalecounter on board G.O.Sars. Photographer at Whalephoto