The first week of sampling
The first days of mountain fieldwork are always a challenge, as after a long winter the muscles need to wake up again to let you climb up the steep slopes of the French Pyrenees. Always making me nervous to see in how much time I can get to the known sites in comparison to the end of last years season....
A student in tow, several sites at altitudes of 1500 – 1800 m have been visited and unfortunately the days were extremely hot, with more than 30°C and hardly any shade along the climb. However, arriving up on the sites is always a pleasure, paying back for the effort by a fantastic view on a wonderful landscape. The tree lake was this years first site and apart of 3 other hikers, we met no one on the way. Arriving up there, we had the pleasant surprise of a large population of Rana temporaria tadpoles, which we had not observed in previous years. After more than 3hrs of sampling we hopped down the steep path, enjoying each brise of wind to cool us down.
The second and third site were easier, as closer to a road. Doing the sampling always attracts the views of others and questions about what we do. Explaining the P³ project always makes me ask the anglers the questions: „Which species of fish occur naturally in mountain lakes?“. At that site I got the right answer:“I guess, none?!“. The fellow anglers were surprised, as they did not realize this until then.
The following day, lakes in another Ariege valley were on the agenda. A very steep slope again, but this time in the shade mainly. Then a first wonderful view when getting above the clouds and after 1h we arrived at the first lake, not yet the end point of this mornings hike.
45 min later, we arrived at a yet higher lake. Hundreds of thousands of R. temporaria tadpoles there and much less tadpoles of the midwife toad. Still, always an amazing site, quiet and beautiful. However, a few dead adult R. temporaria were observed in the lake, either died of exhaustion or when frost caught them at the wrong moment. Now, they mainly served as food for the tadpoles.
Taking a quick lunch in the shade of a rock, we went down to the first lake. Three species of amphibians live there, Bufo bufo, R. temporaria, and A. obstetricans. The latter in steady decline since 2008. Likely the large amount of introduced fish causing difficulties to this sensitive species. During sampling, the clouds started to climb and quickly covered us. The heat of the day gone in a few minutes, leaving us cooled down for the descent.
