Basket star Astrospartus mediterraneus
It looks like a seaweed, a coral, a gorgonian but in reality it is a starfish. We are talking about the Basket starfish, Astrospartus mediterraneus. This starfish lives in close contact with the gorgonians, in particular with the Red gorgonian, Paramuricea clavata, with which it shares its habitat and food. Here where we filmed it we are at a depth of 43 meters, and our submerged reef oscillates from a depth of 42 meters up to 50 meters.
Here where we filmed it we are at a depth of 43 meters, and our submerged reef oscillates from a depth of 42 meters up to 50 meters.
Unfortunately, the strong current and poor visibility due to the turbidity of the water did not allow us to obtain optimal shots, but it is precisely the ideal environment for these marine organisms. In fact, both the Gorgon star and the red Gorgonia seem to find their ideal environment in these conditions, rich in nutrients and plankton which they eat, almost in a symbiotic harmony. Both species are typical of the Mediterranean Sea and now after many years and many dives we see them thrive precisely in these environmental conditions. In fact, where there are the tallest and most prosperous Gorgonians, we almost always find Astrospartus mediterraneus.
Another important factor for these species is the sea temperature. As you can see from the video and photos, our computers recorded a temperature of 17 ° C at about 45 meters in August, therefore in the height of summer. And it is the temperature that one would expect to find at these depths more or less in both winter and summer.
Unfortunately, this is not always the case, the temperature of our sea is warming more and more and changes suddenly throughout the year. Just see what we filmed in a recent article:
relating to a dive in an area not far away made a week before, where we observed a temperature of 25/24 ° from 34 meters up to 40 meters, to find 17 ° C only after 42 meters. This means that the natural thermocline to which these species have adapted over hundreds of years is changing.
If we compare the two dives and take the gorgon star, astrospartus and the red gorgonian as indicators, the differences are substantial, plus this year we have found mucilage throughout the summer in depths over 40 meters. It is not necessary to be a marine biologist or a climatologist to understand that these phenomena are increasingly worrying.