For the twenty-fifth year (or more) in a row I visited the Biebrza marshes and surroundings in Poland. In contrast to previous years, there was still enough water left in the area and I was able to use my floating hut once. That was also limited to one time because the water level dropped rapidly. One reason for the faster disappearance of the water could be that there is very little snow these days. As a result, the frost penetrates further into the ground and the meltwater flows away over the ice, as it were. With a thick layer of snow, the frost penetrates significantly less deeply into the ground and the meltwater therefore sinks into the same ground sooner. And then it flows out of the area less quickly. If winter also continues until later in the year, the melting starts later and therefore also the drainage of the water. Until recently, the end of April/beginning of May was the period in which this took place, now it is, to say, the beginning of April. It is therefore important to assess the situation immediately upon arrival and to make use of perhaps the only day that appears to be suitable.
As can be seen in the previous news items, there are of course plenty of other subjects available. But usually the focus is on the Lepidoptera, the group of butterflies and caterpillars. And despite the many times that I have now visited the area, we keep finding new species of caterpillars. There is also a big difference between one year and the next. Species that are suddenly present in good numbers are not or hardly found the following year. What is clear is that the variety of butterfly species (day and night) is still very large in this area. Searching for caterpillars is a fairly time-consuming activity. That search is not only limited to the daytime hours, but if you use a UV lamp, the nighttime hours are also included. Many caterpillar species hide during the day and only come out when it is dark. And if I am completely honest, that is actually my favorite way of searching. The finds I make, I pass on to a database called “biomap.pl”. This is a database, set up by various Polish nature institutes and aims, among other things, to map the biodiversity of the country. And that is information that can be used again when, for example, large-scale construction projects are planned and one wants to know the presence of scarce or rare species. Where it is of course to be hoped that this is used to the benefit of nature! And, unfortunately, this information also makes clear what the influence of the development of the country is. May the Polish government have the wisdom to preserve the natural state of the country as much as possible. After all, there is more then enough space in this country!
