The Ionian coast of Upper Salento, located in Puglia, is particularly fascinating and rich in marine biodiversity. Characterized by a Mediterranean climate and clear waters, this region offers a variety of unique coastal and marine habitats that support a wide range of marine/coastal flora and fauna. In particular, the Pulsano coastal strip is one of the natural wonders of this area of Ionian Puglia. Located along the Ionian Sea, its coastline is characterized by beautiful golden sandy beaches, crystal clear waters, and a variety of breathtaking landscapes that attract visitors from all over the world.
The coastline has an irregular and jagged pattern, causing the wave motion to tend to concentrate its energy on the “overhanging” parts (cliffs) and thus erode them, while along the “recessed” sections (bays) it tends to deposit debris, feeding the beaches. Therefore, the latter predominantly attributable to the type of so-called pocket beaches, i.e., sedimentary “traps” lacking direct terrigenous input from inland and fed exclusively by what arrives by sea. In addition, the absence of rivers along the coastline from Taranto to Santa Maria di Leuca means that there is no input of muds and clays into the sea, making the water transparent and the beaches formed essentially of organogenic sand. This sand is composed mainly of decaying organic material, such as fragments of living organisms and especially shells, crustaceans, bryozoans, algae, plants and other marine organisms belonging to the many Phyla present in the sea.
This type of beach can have a unique appearance and can be particularly interesting for nature lovers as they will enjoy, perhaps with a small magnifying glass, recognizing the marine species that give rise to these wonderful natural miniature sculptures. Organogenic sand is often very soft and can offer a pleasant feeling walking on it barefoot. In addition, organogenic sand can be an important habitat for small marine creatures that feed on decaying organic matter. Beaches formed by organogenic sand are a fascinating example of how nature can create unique and diverse landscapes around the world.
Many are the shells that the sea brings to the beach, to the delight of children as well as collectors. Many of them have a perfectly circular hole cleverly exploited by children of every generation to collect necklaces and bracelets. This hole is nothing more than the trace left by a predatory gastropod mollusk that managed to make the hole, using its tongue, equipped with special teeth, and gastric juices to feed on its owner. On the beach it is also possible to see strange brown vegetable balls, the origin of which is not easily identifiable; these balls, called egagropils, are nothing more than aggregates of Posidonia oceanica fibers compacted by wave motion on shore.
But they can give us indications of what beauties are hiding underwater near the bays. Sometimes in one of the largest and most beautiful bays, known as “Fatamorgana” or for the more nostalgic “Lido Silvana,” long leaves ranging in color from green/brownish to dark brown can be found on the shore. They are indeed leaves of a marine plant, and not of a seaweed, which is very important for the whole marine ecosystem. This plant is Posidonia oceanica, a marine phanerogamous plant that lives completely underwater and produces flowers and seeds. Posidonia is common in the coastal waters of Pulsano, where it forms extensive underwater prairies. These prairies are considered one of the most important and productive habitats in the Mediterranean as they provide oxygen and shelter to numerous species of organisms, contributing to marine biodiversity, such as damselfish, salps, sand mullet, but upon careful observation, among its leaves or rhizomes, one discovers in addition to the now rare Pinna nobilis (castanets), pipefish, seahorses, octopuses, shrimps and fry of all species that find shelter from predators in the dense labyrinth.
Always looking for food on the sand we find many crustaceans, such as the small and numerous Boxer Hagfish, the Pomegranate Crab, and the Drag Crab which has peculiarities of having on the last pair of legs large black spots: these, when the crab is sunken, simulating large eyes, make predators believe that the crab is much larger than it really is. Other predators characteristic of sandy environments are the Echinoderms with the large stars of the genus Astropecten (Astropecten bispinosum and Astropecten irregularis) and the various urchins such as Echinocardium cordatum and Spatangus purpureus, which have short, brittle spines that look like fragile hair. Among the Echinoderms, always present are the holothurians or Sea Cucumbers (Holothuria tubulosa), some of the most important detritivorous organisms of the seabed, as they feed on the organic particles on the seabed and put nutrients back into circulation. They also possess great regenerative capacities: in fact, they are able to eviscerate, that is, expel the long intestine, aquiferous lungs and the one gonad, to distract a possible predator and facilitate escape, except that they then regenerate the organs in a short time. They can emit long, sometimes toxic, sticky filaments from the cloaca with a defensive function, called Cuvier's tubes, with which they entangle predators.
The most common fish include flatfish, such as turbot (Botus podas) and sole (Solea vulgaris), which have adapted to this environment through a drastically laterally flattened body, such that they rest on their sides and move with body undulations.
Often it is easy to observe several tracines (Trachinus araneus, T. radiatus, T. draco), mormoras (Lithognathus mormyrus), some gobies and especially mullet (Mullus barbatus), which incessantly dig with their 2 mustache-like tactile barbs on the bottom in search of prey, often escorted by other fish hoping to take advantage of their work.
The sandy bottoms of the Pulsano bays, as we have seen, have numerous communities, despite the apparent uniformity of the substrate and the absence of those microenvironments that characterize a rocky substrate instead. Therefore, each swim with a mask will be like participating in a treasure hunt, where the prize is to enjoy the wonders that the sea can offer only to those willing to discover.
