28.03.2019 – The shape of water
Our Stenella embarked on a wonderful tour this afternoon, where Short-finned pilot whales (Globicephala macrorhynchus) and Bottlenose dolphins (Tursiops truncatus) practically escorted us away from the rainfall along the coastline. While every tour is alot more comfortable without it, rainfall is absolutely necessary in keeping both the coastline and our oceans healthy.
Despite receiving a substantial amount of nutrients from the cold waters of the canary current, Madeira’s waters are considered oligotrophic, meaning they contain a relatively low concentration of nutrients. The constant movement of water on the island, however, helps maintain a steady inflow of nutrients into the islands coastal waters.
Madeira is an island shaped by water; rainfall and running water through rivers, streams and the flower island’s famous levadas erode and shape the coastline, carrying sediment into the oceans which in turn helps fertilize the phytoplankton that establish the necessary foundation for the marine food web.
Of course sediment entering the ocean doesn’t always favor the environment, particularly one with humans in it. Excess sediment from construction waste often settles on the reefs lining the archipelagos coastline, suffocating the macroalgae. Pesticides used in agriculture along the coastline may also be transported directly into the ocean, contaminating and bioaccumulating in marine organisms. The viscuous element also continuously erodes the basalt surfaces lining the islands cliffs often resulting in rockfall. The works on the rock wall overlooking the marina in Calheta have changed logistics for our company since 3 months now. Workers „cliffhanging“ along these walls are removing loose stones that may pose a danger to the marina and are installing a large net to cover the entire surface.
Of course, the body of water we concern ourselves with at Lobosonda is the mother of all waters here, the Atlantic ocean. She is also responsible for shaping this beautiful island and, of course, for some beautiful cetacean sightings.
By Paula Thake
Sightings of the day
15:00 Bottlenose dolphins, Short-finned pilot whales