Unique sightings #2
Updated: Jul 29
2 years ago I made a post of the unique sightings of the field-season 2021 so here we are again, before our 2023 field-season starts, I wanted to summarize our unique sightings of last year's super successful fieldwork season, 2022! The focus is on all the other species that we have seen last summer that were not our study species, the common dolphins.
Sei whales On one of our surveys we also saw blows. When our drone flew over them we realized that it was a Sei whale (Balaenoptera borealis) mother and calf pair! We recognized them from the head, where only 1 ridge is visible, and the dorsal fin was almost entirely erect and upright. These two individuals were so calm and relaxed that we could leave the engine in neutral and simply fly slowly over them with the drone. It was a wonderful sighting!
Brydes whale foraging with spotted dolphins
On this particular sighting one drone pilot (me) was surveying resting common dolphins, and not even 100m next to this pod we saw a blow. So the other drone pilot (Lorenzo) decided to check them out with the second drone. At first we thought it was a Sei whale (they can look quite similar at first glance). But the dorsal fin looked smaller. So did the individual. Upon checking the images later we saw 3 ridges on the head, which pointed towards a Brydes whale (Balaenoptera brydei)! Next to the Brydes whale were spotted dolphins. They were foraging together and we filmed the Brydes whale surface foraging 3 times!
Short-fin Mako shark
On a very calm glassy water day whilst waiting for the right time to film the common dolphins we suddenly saw a dorsal fin gliding at the sea surface. It was coming right toward us. The gopro was ready so we immediately put it in the water, facing the short fin mako shark (Isurus oxyrinchus), hoping it was in the frame. It came very close and indeed, it was perfectly in frame. This individual was not scared of us! (they usually are but we were calm enough to keep it at the surface :))
Ever since we started a new collaboration with Sperm whale Scale, we have been able to also collect some sperm whale (Physeter macrocephalus) data when we encounter them. Sean O'Callaghan, who started off as a team member with us, then set up his own PhD in Norway and made part of his fieldwork here in the Azores! On our last field-work day we had no more common dolphins in the afternoon so decided to spend some time collecting sperm whale data for Sean on the South coast of Sao Miguel, while he was on the North coast of the island, collecting data on another sperm whale social unit. Now that's team work!
Last year one of our teammates from 2021, Luana Clementino, joined us on board for a day! It was a morning and afternoon trip, and in the afternoon the waves started to break and become foamy. The whale watching boats were also still with the dolphins, so we waited at a distance until it was our turn to survey the dolphins. Suddenly we saw a brown coloured shadow pass us next to the boat. It was a mobula ray (Mobula tarapacana)! Due to the waves and bad visibility, this was the best shot we got.
Striped dolphins relaxing
You can tell by the color of the water that we were still in the springtime here. The plankton was still present in the Azorean water making the colour of the water more greenish. We encountered a pod of striped dolphins that day and they appeared calm. In the Azores these species are often very high speed and skittish. Since they were calm at the distance that we kept, we decided to send the drone over to them and not interact with this pod with our boat. We sent the drone to about 1km distance so we could still keep the drone in the Visual Line of Sight (VLOS) and not disturb this reactive species. The result was that we could follow them with the drone and they did not even dive (which usually happens when approached by boats).
This was possibly the best sighting we had of common dolphins. However, this blog is about other species, so I will focus on the tuna! They were foraging together with the common dolphins. If you look closely, you can even see that the tuna is much larger than the dolphins! We believe that this day the tuna species were the Bluefin tuna (Thunnus thynnus), considering they were between 3.5 and 4 meters. That is almost double the size of the common dolphin! (max 2.5m). However we are unsure about the species, since Big Eye tunas (Thunnus obesus) are more likely to be in the Azores in that time of the year and can become very large too!
A whaling boat!
Last but not least, we also filmed humans in a whaling boat! Our co-founder Laura Gonzalez and logo creator Anxo Cao were rowing at sea in the renovated boat that was used to hunt sperm whales when it was still legal (whaling has been halted in 1986).
So that's it! What can we say, we became so efficient that our focus of common dolphins was very spot-on this summer! So our special sightings list is not very high. We also started our season later than last year, in July, so we missed baleen whale season (although we could not complain about the Sei whale and Brydes whale sightings).
2022 fieldwork season was funded by KNAW and INREF
Author: Fadia Al Abbar