10.06.2022 – Sunscreen

What an eventful day out in the sun for our team! The suns rays were already. burning down onto a flat ocean in the morning, but the conditions set a beautiful stage for encounters out on the ocean today both above and below the surface. Both boats managed wonderful encounters with Short-finned pilot whales (Globicephala macrorhynchus) and Atlantic spotted dolphins (Stenella frontalis) in the morning and in the afternoon we enjoyed sightings with more spotted dolphins as well as a pod of Short-beaked common dolphins (Delphinus delphis) and Striped dolphins (Stenella coeruleoalba).

All our sightings were fantastic but the hours in the sun left both our crew and guests a little sunburnt. Some hydration and after-sun can always do the trick with us but what solution do cetaceans have for sun exposure? Our planet has an ever-growing hole in the ozone layer which is meant to protect us from the suns harmful UV rays and some cetaceans can spend up to six hours at the surface!

We know that many species produce melanin, which is the protective pigment against UV rays that humans also have in their skin. To protect their cells from UV damage, Sperm whales have proteins to protect their cells which work in a process similar to how human bodies produce antioxidants in response to the free radicals produced through over-exposure.

Although marine mammals have an in-built defence system against UV-rays from the sun, too much exposure is still harmful and the level of damage poorly studied. Serious skin diseases like cancer may also be possible in cetaceans and the probability is rising in the face of the expanding ozone hole. An increase in sightings of melanistic animals, that have a darker skin coloration through a genetic mutation that results in an overproduction of the skin pigment melanin, may be an indication of how changing conditions are affecting these animals.

So, basically, the same rules apply for all creatures under the sun. We need the suns rays to live but also must protect ourselves from them.

By Paula Thake

Sightings of the day

Ribeira Brava

10:00 Atlantic spotted dolphins, Short-finned pilot whales

14:30 Atlantic spotted dolphins

Stenella

09:00 Atlantic spotted dolphins, Short-finned pilot whales

15:00 Atlantic spotted dolphins, Short-beaked common dolphins, Striped dolphins