The Swimming Head
December 14, 2022
Turtles have survived dinosaurs, continent shifts and ice ages. But whether they survive humans is still unclear
December 18, 2022
A short window of agreeable weather emerged within the many stormy days this week and our team decided to use it. We travelled on seas as silver as the overcast sky all the way to the waters outside Camâra do Lobos to meet a small group of Bottlenose dolphins (Tursiops truncatus). The animals were moving in their usual tightly knit formation and the pod even contained some calves and curious juveniles. The latter even swam up to the bow of our Stenella to glide through the waves at our bow.
Bottlenose dolphins are the best researched cetaceans worldwide and also belong to the best documented species here in Madeira. Using Photo-ID local researchers were able to identify several individuals within the large population and discovered a few island-associated animals that use a large habitat that encompasses both Madeira and Canary Islands. This close relationship to Madeira as a habitat makes Bottlenose dolphins potential ecological indicators, species that researchers use to track any changes in ecosystems by monitoring changes in their population and population dynamics. Today we know that natural systems are changing at a very fast rate as a result of anthropogenic activity, so understanding and measuring these processes is extremely important.
Our team recently attended a workshop where researchers from the Madeira Whale Museum explained their current research about the effects of whale-watching on cetacean populations in Madeira. The focus of this research is monitoring the well-documented populations of Bottlenose dolphins and Short-finned pilot whales (Globicephala macrorhychus) and measuring their stress levels. This is done using pho-Id data and collecting samples, such a water samples from the blowhole and blubber samples to measure cortisol levels. While demographic research has shown little change due to an increase in whale-watching, results from the sampling are still pending.
Such research underlines the importance of learning more about these populations and how our activity affects them so we can find better ways in future to protect them.
By Paula Thake
Sightings of the day
Stenella
10:00 Bottlenose dolphins
