My first swabs!
I had the opportunity to leave Toulouse and spend some days in the beautiful Ariège to assist in P³ field work. Being hydrologist, I was in my element: water not only from below (lakes), but a lot of it also from above. Before, I had pictured myself sweating in the August heat while climbing up the mountains – it turned out I was very lucky to have packed my rain coats and pants. But despite three days of rain, I had a great time.
Our first sites are famous among geologists for the Lherzolith, a type of rock which was named after the place. It is also a popular fishing spot and during sampling we can observe a couple of fishermen appearing in the rainy fog along the shore of the lake. One of the fishermen approaches us to ask us what we are doing. From him we learn about a relatively new fishing technique that leads to little polystyrene balls appearing here and there in the littoral zone. He is not very happy about this new threat of pollution, nor are we. We collect some of the little plastics in order to show it to our colleagues later. “You can find these now along the shoreline of lakes and in the brooks, as they often detach when a fish bites”, says the fisherman.
The next day we hiked up to a shallow lake at 1800 m, populated with makrophytes. It is away from the GR10 path, so we don’t see any hikers here. Nevertheless, we meet a lot of tadpoles – and I have my first-time-ever tadpole-swabbing experience! During our two hours of sampling, we fight against freezing hands, wind and rain. The water is cold, not like the day before where we could almost warm up our hands in the lake. After a careful hike back down to the parking over slippery rocks and mud, we have fun taking selfies before warming up in the car on our way back home.
The third day starts with a long drive up to the most eastern part of the Parc National des Pyrenees, one of the most beautiful spots of the mountains I have yet been to. With its colorful granite rocks and breathtaking views, it is a tourist attraction. We meet many visitors already heading down escaping the bad weather before our field day even started. After 3 hours through rain and some snow Dirk, Judit and I reach our first sampling site, a lake where livestock was reassembled in former times. The little cabin next to it is crowded with a family who stayed overnight as well as some hikers taking a break from the rain. Our hands just won’t get warm this time which makes labelling our samples very difficult. A hint of sun makes us hope for more as we head upwards again, but not much of luck. We arrived back at the next lakes as cold and wet as we left it.
Dirk tells me how he witnessed the disappearing of tadpoles from the lake by the year 2013. I feel frustrated. I get a new rush of motivation to save the frogs and start thinking about the many unknowns there are when it comes to amphibian extinctions and the spread of the pathogen Bd. Considering the phenomenon from a hydrological point of view, it would be important to know which kind of hydro-climatic regime is important for pathogen spread, as well as if or how the different water bodies are connected through the landscape. I have seen different lakes in a variety of landscape settings and degree of human influence, factors that are able to shape water quality as well.
It is getting late when we finally finish our day and soaking wet, cold and hungry we warm up in the car on our way back. My field week was a very welcome escape from the city life in Toulouse. I come home with new inspirations and knowledge. I also learned that the Pyrenees can be very rainy in August, but even when wet and cold, they are no less beautiful.