A post by our guest blogger Katrin, a Master's student on the "Biotechnology and Applied Ecology" course.As every year, the ecology and environmental protection students at Zittau/Görlitz University of Applied Sciences are offered a marine biology field trip. From 23.08. - 30.08.2015 they went to the Adriatic Sea, to Croatia. The purpose of this wonderful experience is to get to know the sensitive ecosystems of the sea. In addition to researching the flora and fauna visible to the naked eye, the smaller creatures, the plankton, are also studied. As an ecology student, I had to go on an excursion like this at least once and I can tell you that it was definitely worth it! We spent a week on the trip in total, with two days planned for arrival and departure by coach. Sounds terrible at first, but it wasn't. Of course, the journey was very long, but on the journey towards the Mediterranean, crossing the Czech Republic, Austria, Slovenia and finally Croatia, you could already see a wonderful, slowly changing landscape. To pass the time, everyone was given a topic to talk about beforehand, which had to do with the Mediterranean. From about Prague onwards, everyone was allowed to give their presentation at the front of the bus with a microphone and video transmission via TV - it was kind of funny. We made a stopover in Vienna with an overnight stay: a beautiful city - I would have liked to stay longer![caption id="attachment_427" align="alignnone" width="459"] St. Stephen's Cathedral on Stephansplatz[/caption][caption id="attachment_435" align="alignnone" width="440"] Natural History Museum on Maria-Theresien-Platz[/caption][caption id="attachment_425" align="alignnone" width="469"] Volksgarten Vienna[/caption][caption id="attachment_423" align="alignnone" width="469"] Vienna and its beautiful alleyways[/caption]After we ecologists of all ages had made the city unsafe, we continued on to Pula the next morning. If you hadn't missed the whole journey, you could see a vast forest landscape from Slovenia onwards at the latest, and it became increasingly mountainous. The huge agricultural fields were increasingly replaced by smaller polycultures, which is more pleasing to the eye of the critical ecologist, and we made a short stop at the border between Slovenia and Croatia to exchange money. We could already smell the sea and a little later, as we crossed the Dinaric Mountains, we could finally see it. When we arrived in Pula and were looking for the sea school, we were greeted warmly by the small narrow streets - they almost didn't want to give us and the large coach away. Thank goodness we had an experienced bus driver at the wheel who maneuvered us - no idea how - out of the clutches of Tommaseova ulica.[caption id="attachment_444" align="alignnone" width="469"] First view of the bay after arrival[/caption]The youth hostel was conveniently located right next to the sea school in the bay. We were able to marvel at some beautiful sunsets here. Some beautiful sunsets could be admired here. Like this one, for example:The journey to Pula had taken a little longer than planned and so we "only" had free time that evening, which consisted of quickly grabbing dinner, moving into our rooms and clearing the coach of the binos, microscopes and identification books we had brought with us. The marine school also welcomed us with a short presentation and we discussed the next day's plans. The program included: Theory - what we might see in the water; of course active snorkeling - so what we actually see and finally the evaluation in the form of species lists - after all, everything has to be documented!For two days we were accompanied by the nice staff of the marine school. They were out in the water with us in small groups. On the first day (day 3), they showed us the "in-house" bay, where we also "snorkeled in" first. When we saw something, they enthusiastically explained everything we wanted to know, and we were able to see this (and much more):[caption id="attachment_429" align="alignleft" width="692"] Black sea urchins[/caption][caption id="attachment_433" align="alignnone" width="610"] Ringed seabream[/caption] In the afternoon we looked at the seagrass meadows in another bay. At first glance, seagrass beds might seem a little boring, because if you really want to see something, you need a trained eye and a healthy lung volume to stay underwater long enough. Here you can discover sea needles and seahorses, among other things, and of course you need a bit of luck... Seagrass meadows are only found in a few coastal areas around the world, including the Adriatic Sea off the Croatian coast. They form very special ecosystems on a sandy substrate. They also provide excellent food and hiding places and are the nursery of many species of fish, crustaceans and molluscs. Unfortunately, these wonderful ecosystems are in serious decline. Today, only remnants of the vast grass carpets remain. Eutrophication and water pollution are the main culprits, clouding the water so that the light-requiring plants can no longer grow. But large-scale trawling, anchoring and construction work also lead to the death and permanent disappearance of the seagrass meadows, and of course after our snorkeling trip in the seagrass meadows we got a few samples for the microscope from the marine school, so that even the smallest organisms living in the Neptune grass can be observed. It's funny to see a small turban snail(Monodonta turbinata) or seagrass shrimp(Hippolyte inermis) up close. In total, we were able to identify over twenty different species - both animals and algae - under the microscope. (Afterwards, by the way, all the specimens were released back into the seawater in good health.)Day 4 and the program included cave snorkelling and plankton identification. We went out in two boats for this. Cave snorkeling was primarily intended to show us the changing fauna of sessile filter feeders, whirlpools and tentacle catchers depending on the water current and light conditions. Sponges and barnacles, for example, tend to occur as filter feeders at the grotto entrance. However, the yellow crust anemone(Parazoanthus axinellae) was also found at the end of the grotto, where no more sponges are to be found. the plankton samples were taken on the way back from the boat. Samples were taken from the surface water and from a depth of 7 meters. The abiotics - i.e. pH value, conductivity, salinity and water temperature - were also measured. Our plankton determinations revealed over 30 different species from the surface water alone. As expected, the species richness at a depth of 7 m was somewhat lower, as the radiation intensity decreases with every meter of depth.[caption id="attachment_424" align="alignnone" width="694"] In front of the entrance to the cave[/caption][caption id="attachment_443" align="alignnone" width="694"] Grotto snorkeling[/caption][caption id="attachment_428" align="alignnone" width="694"] Sea anemone at the back of the cave[/caption] Day 5 of our trip and we went to Cape Kamenjak, the southern tip of Istria. Of course, we snorkeled here again and compiled a species list. Some of the species were already pretty good, so it was twice as much fun. For me personally, this was the most beautiful snorkeling spot we have seen so far. You could see an incredible abundance of species in the clear water, swim through another rock grotto and snorkel over a breathtaking rocky bottom.[caption id="attachment_439" align="alignnone" width="627"] Italian crab[/caption][caption id="attachment_431" align="alignnone" width="592"] Red algae[/caption][caption id="attachment_445" align="alignnone" width="714"] A beautiful fried egg jellyfish[/caption][caption id="attachment_431" align="alignnone" width="592"] Red algae[/caption]Cape Kamenjak is considered a protected natural landscape in Croatia and thus enjoys legal protection; however, it is freely accessible for vacationers - even accessible by car for a small fee (of course). After the snorkeling trip, it was time for us to explore the predominant Mediterranean garrigue vegetation here; incidentally, one or two of us also concentrated on the fauna. In addition to what we initially thought was a grasscutter ant, which turned out to be an omnivorous and native Pheidole pallidula (possibly! exact identification was not possible!), we discovered, among other things the Mediterranean grasshopper(Acrida ungarica mediterrane), which was well camouflaged in the dry grass, the nasal grasshopper(Acrida ungarica), theItalian grasshopper(Calliptamus italicus), a sail butterfly(Iphiclides podalirius) and much more, which made the entomologist's heart beat a little faster. The botanists among us (no, actually all of us together) were able to identify almost 40 different plant species on the way from the rocky coast to the parking lot where the coach was waiting for us.[caption id="attachment_451" align="alignnone" width="712"] The Mediterranean vegetation[/caption][caption id="attachment_436" align="alignnone" width="739"] Nose grasshopper[/caption][caption id="attachment_438" align="alignnone" width="658"] Mediterranean grasshopper[/caption][caption id="attachment_434" align="alignnone" width="660"] We ecologists at the identification[/caption]The last day (day 6) in Pula could be freely organized by us. But I think pretty much all of us went snorkeling again. In the evening we went into town together as a group, ate together and had a few last nice memories from this also very interesting town. Our return journey took us back the same way, but with a really worthwhile stopover in Postojna, Slovenia. There we visited a breathtaking cave system. The guided tour through this stalactite cave lasted two hours, passing massive stalagmites and stalactites. many thanks to M. Auerswald and E. Baumgartner for the great underwater pictures! And many thanks to the rest of the group for the wonderful time together.