Friday 6 September 2019

Closing the snorkeling season

With the arrival of the first autumn rains and cold winds we are now saying goodbye to the summer season. Therefore in this post we'll sum up a few more observations and finds from our latest snorkeling trips in the Adriatic sea, more precisely in the Gulf of Trieste. The Abudefduf we found in August (see here) was observed repeatedly, every time we visited the site at Tanki rtič/Punta Sottile. Our colleague marine biologists identified it as a probable Sergeant-major Abudefduf saxatilis on the basis of close-up photos, but further researches are still underway. As we already mentioned, this find represents a new species for the Gulf of Trieste. 
Among the other highlights of the summer season is certainly a close-up encounter with an Atlantic Bluefin Tuna Thunnus thynnus, a fish you don't usually swim with! The encounter was brief but very exciting as a mid-sized tuna (about 80 cm in length) swam at full speed about half a meter away from us, while we were snorkeling not far from the coast. The fish was obviously in hunting mode, as for a few moments the sea "boiled" and Mullets Mugil sp. were jumping out from the water in all directions. After approaching the shore to knee-deep water, the tuna made a few leaps and disappeared back towards the open sea. Unfortunately the encounter was too brief to take any photos... nevertheless we were also too astonished to attempt any photography. However here is a photo selection of the other marine organisms we managed to observe and photograph (with a Fujifilm Finepix XP 140) during all our recent excursions. Another similar post with more species can be found here. Enjoy!
The impressive and harmless Mediterranean Jellyfish Cotylorhiza tuberculata was seen several times, including up to 9 individuals in one afternoon.
...some were in really shallow water, floating among swimmers. Pity most people didn't even have the chance to admire these beauties from below.
The jellyfish serves as shelter to juvenile fish.
Common Jellyfish Aurelia aurita
The alien Sea Walnut Mnemiopsis leydi is a highly invasive species. It can be present in very large numbers by the end of the summer, when water temperatures are higher. Unfortunately the northern Adriatic is literally packed with them. Fortunately for swimmers and snorkelers, this is a Comb Jelly (Ctenophora) and not a true jellyfish, so it has no stinging cells.
Salp Salpa sp. - a curious floating animal belonging to the tunicates (Tunicata).
Sergeant-major Abudefduf saxatilis - "our" alien friend from the tropical seas.
Mediterranean Chromis or Damselfish Chromis chromis - the closest (and only) relative of the Sergeant-major in the Mediterranean (note the similarity).
Garfish Belone belone
Gilt-head Bream or Orata Sparus aurata
Sand Steenbrass Lithognathus mormyrus
Painted Comber Serranus scriba
Goldline Sarpa salpa
A mix of seabreams: Two-banded Diplodus vulgaris and Sharpsnout D. puntazzo
Sharpsnout Seabream Diplodus puntazzo
Mullet Mugil (Liza) sp.
Adriatic Blenny Microlypophrys adriaticus
Peacock Blenny Lipophrys (Salaria) pavo
Dalmatian Blenny Microlipophrys dalmatinus
Tompot Blenny Parablennius gattorugine
Giant Goby Gobius cobitis
Black Goby Gobius niger
Red-mouthed Goby Gobius cruentatus
East Atlantic Peacock Wrasse Symphodus tinca
Red/Blunt-snouted Mullet Mullus surmuletus/barbatus
Saddled Seabream Oblada melanura
Mediterranean/Big-scale Sand Smelt Atherina hepsetus/boyeri
Yellow Tube Sponge Aplysina aerophoba
Noble Pen Shell Pinna nobilis
Snakelocks Anemone Anemonia viridis
Kidney-shaped Sponge Chondrosia reniformis (left) and 
White Warty Seasquirt Phallusia mammillata (right).