07.01.2020 – Grey zone

One of the many beautiful things about the variety of life surrounding the island of Madeira is the fact that all the different organisms that can be encountered here nurture a different relationship to the archipelago’s waters. In the last days we had the pleasure of meeting the familiar faces of Bottlenose dolphins (Tursiops truncatus) and Short-finned pilot whales (Globicephala macrorhynchus), two species that are thought to show distinct residency patterns to the islands waters. They can be seen all year round, irrespective of season or water temperature. Then there are the seasonal visitors which include the Atlantic spotted dolphins (Stenella frontalis) and the Short-beaked common dolphins (Delphinus delphis) whose presence is largely dependent on a number of different factors. 

Water temperature is assumed to be the decisive factor in the case of these two dolphin species. The spotted dolphins are more abundant in summer where the waters around the island heat up while the common dolphins prefer the cooler waters during the winter season. While the two seem antagonistic in their relationship to the islands waters and thus should occur separately, the lengthening of the transition seasons, the grey zone periods of the year, allow us to witness these seasonal visitors almost as an ensemble in one tour. The was the case today and such sightings are definitely rewarding since both species are incredibly interactive and beautiful to encounter. Despite the advantages this may have for whale-watching this may also be proof of the reality of climate change and how we can expect this phenomenon to surface in our oceans in future. What matters is that these charismatic creatures only motivate us more to protect our oceans and unite in the fight for a healthy natural world which we and these creatures so dearly depend on. 

By Paula Thake

Sightings of the day

Stenella

15:00 Atlantic spotted dolphins, Short-beaked common dolphins, Loggerhead turtle