18 September 2012

CSR_18 (September 10th - 16th)

The final week of the season. As the summer draws to a close, the weather becomes more unpredictable. We were able to venture out the first day and soon found a sperm whale which we acoustically tracked and took pictures of for our photo-identification catalogue. This animal bore marks which looked like they were due to a collision with a ship. The afternoon brought striped dolphins, that rode the bow wave made by Pelagos, before heading back to Sanremo to avoid the forecasted bad weather conditions.
We were unable to leave the harbour for the next two days due to high winds and waves. The group was able to fully appreciate the ferocity of the sea from the roof of the Oceanographic Museum of Monaco. The next day, we had lectures about the cetacean species found in the Mediterranean, and using our photo-ID techniques we found a match for the sperm whale we had sighted earlier in the week. He was called ‘Cut’ presumably because of the collision mark in front of his dorsal fin.
We left the harbour early the next day and transited along the coast. The sea was alive with feeding tuna – quite a sight to see so many jumping fish from the water. At the time we were above the slope of the ocean floor, a productive area favoured by many cetaceans. However, we did not expect to see a fin whale which usually feeds on krill - which are generally found in the pelagic area, further out to sea. But, sure enough, we saw the distinctive tall vertical blow of the largest cetacean found in the Mediterranean. We followed the fin whale on a ‘zigzag’ route, commonly associated with feeding behaviour in this species.
The sighting conditions were tough, with periods of the day spent in ‘negative sighting conditions’ – when waves are breaking and it becomes increasingly difficult to see cetaceans. We spent the night in Saint Jean, sheltered from the wind.
The final day of the week proved to be our most exciting, providing a glorious end to the 2012 CSR season. The day ended with four sperm whales synchronously vocalising, surfacing within minutes of each other. We raced between animals, attempting to get photo identification pictures and photogrammetry data for each whale. While the whales were diving, we were treated to a symphony of clicks, including codas, chirrups and clangs, which are sounds usually associated with social behaviour among sperm whales. The final encounter involved a sperm whale swimming upside down under Pelagos, and then spy-hopping at the stern so that it could get a better look at us. What a way to finish the season!

Viridiana, Eva, Martina and Luke

Following link is for participants of this week's expedition, showing the ship's route, pictures of some of the sightings and of some moments of the cruise which were memorable (or even not so...)

Ai partecipanti al turno è dedicato uno spazio con il percorso effettuato durante la settimana, le foto di alcuni avvistamenti e qualche immagine dei momenti da ricordare - importanti e non