11.11.2019 – Middle sea

After spending a week on my little Mediterranean home island, Malta, I returned to Madeira with eagerness and excitement to encounter cetaceans once again out on the vast Atlantic Ocean. When you spend even a small amount of time on another very different archipelago, making comparisons is pretty much inevitable. The two differ in their culture, their geological history, their landscape but also in the diversity of their associated flora and fauna. Madeira, for instance, boasts a much larger diversity in marine macro-fauna, such as whales and dolphins, than the Mediterranean.

There are, however, some similarities as there are differences in the diversity of life around the two archipelagos. The Strait of Gibraltar connects both water bodies, enabling marine species that inhabit the temperate waters of the Mediterranean to migrate into the Atlantic and vice versa. Many of the fish species that we encounter in the Mediterranean such as the Dusky Grouper (Epinephelus marginatus), the Rainbow wrasse (Coris julis) and the Parrot fish (Sparisoma cretense) can also be seen on coastal reefs here in Madeira. The same goes for certain cetacean species like the Short-beaked common dolphins (Delphinus delphis) we saw today. These seasonal visitors are frequently sighted during the winter months in Madeira but are unfortunately a rare sighting in the Med. The reason for this significant decrease in the population is the massive overfishing and the resulting depletion of their prey in the middle sea. Thankfully the effects of overfishing are more diluted in the vast Atlantic Ocean but scientists are still carefully monitoring populations.

The highly vulnerable Loggerhead turtles (Caretta caretta) are an expected sighting during sunny days on the Atlantic and come to the Portuguese archipelago to rest and feed during their long journeys through the oceans. Malta is more particular as a habitat for these animals with several sandy beaches officially dubbed as nesting beaches. Although Loggerheads have been observed laying their clutch of roughly 90-110 ping pong sized eggs in these specific sites, the beaches have still not been converted into protected areas and are flooded with people in summer. In Madeira more intensive research and monitoring is conducted on the species and injured individuals are also brought to a much better financed rescue centre (a must for all places with turtle sightings) here on the island than in Malta. 

My home island is also a nesting area for other philopatric animals; marine birds enjoy laying their nests in the crevices of our soft limestone cliffs, particularly on the islets Filfla and Cominotto. One of these species, the Scopoli’s shearwaters (Calonectris diomedea), is considered the Mediterranean cousin of the Cory’s Shearwater (Calonectris borealis). The two species are in fact so closely related that until fairly recently they were considered as a single species (Calonectris diomedea borealis). Again, Malta can learn a lot from Madeira. In Portugal the establishment of terrestrial and marine protected areas has allowed populations of previously endangered species of marine birds to recover. Controlling light pollution and the habitat destruction is the next anticipated step in the nationwide attempt to protect migrating and nesting marine bird species. In Malta we have badly monitored protected areas for these animals and unregulated hunting, where several endangered species are often shot from the sky. 

Don’t get me wrong; my intention here isn’t to put anyone off Malta and promote Madeira. I love my home island and am proud to be Maltese. I am especially proud of all the people who dedicate time and effort to fight for the environment back home. There is, however, plenty of room for improvement on several fronts and regarding the management of and approach to environmental issues Madeira simply sets a brilliant example.

By Paula Thake

Sightings of the day

Stenella

15:00 Short-beaked common dolphins, Loggerhead turtle