28.11.2018 – Suddenly
December 7, 2018
30.11.2018 – In flow
December 11, 2018
During todays afternoon tour, our spotter directed us to a mixed group of Bottlenose dolphins (Tursiops truncatus) and Short-finned pilot whales (Globicephala macrorhynchus) who were travelling very fast and engaging in several dives. We soon found out what may have lured the animals into the depths; a half-bitten deep-sea squid was drifting dead at the surface, indicating that the cetaceans may have been hunting. Luckily, cetaceans must resurface to breathe so we waited patiently to see some dispersed blow-sprays at the surface for a longer period of time.
Apart from indicating the obvious presence of cetaceans at the surface and often enabling us to identify a species from afar, the spray from the blow-hole is literally full of vital information. Sampling the exhaled spraywater from blowholes has evolved as a new non-ivasive method amongst scientists studying cetaceans, granting them insight into the health status of the animal as well as enabling them to obtain real-time hormonal data. Blowhole water also contains DNA samples of the animal itself as well as from the mircobial flora inhabiting its airways. Some of these „hitchhiking“ bacterial communities inhabit the lungs of cetaceans before being projected out of the blowhole during exhalation, allowing them to further infect another host.
The sampling procedure is very delicate as the water sample can easily be contaminated with seawater if conditions aren’t ideal. However, if successful, the procedure may aid scientists assess the genetic diversity and health of marine mammal communities.
After some time, these dispersed mini-fountains of information soon appeared at the surface after the animals finished hunting. This allowed our guests to not only admire these remarkable creatures but also to respect the fantastic work of our spotter, who was able to locate the blowhole-sprays depite the misleadinfg white foam from the heaving Atlantic ocean.
By Paula Thake
Sightings of the day
Stenella
10:00 Bottlenose dolphins, Short-finned pilot whales
