12 May 2017
Finally, a sunny and (relatively) warm day!! And a night of catching frogs, although just in one locality, since temperature dropped during the night and frogs gradually stopped their calling activity. Anyway, we managed to collect 13 new frogs from a locality in high radiation area, around 1 km from the nuclear power plant, the same we visited last year during our first day here (“Day 2 At the shadow of Chernobyl reactor 4“).
This is a crucial locality since it’s one of the very few places in which we have found big enough treefrog populations inside highly contaminated areas. As I mentioned in previous days, the areas that still maintain high radiation levels in Chernobyl are small, so not many options when you need to find ponds suitable for treefrog breeding inside there. And that’s why we are so happy with these new 13 frogs, they are essential for estimating the effects that living in high radiation areas has on amphibians genetics and physiology.
Our day started helping again our Ukrainian colleagues in their work checking breeding performance of birds using next boxes in different areas of the Exclusion Zone. It was quite nice to be around on a sunny day, looking for birds. Seeing a warm and sunny day, after all the cold, freezing, ones was a relief, but also put us in a constant stress looking for clouds, wind or anything that could turn the weather into nasty for frog breeding again.
We even had time, after lunch in the field, for “the official photo” of the #ChernobylFrogs17 team.
At the end, temperature cooled dawn a bit. We decided to sample in the locality close to the Nuclear Power Plant, inside highly radioactive area, that we visited last night. For our experience last year, we knew that this was a good place for treefrogs. So, if they were not present, it was because breeding activity has stopped due the cold weather.
As soon as we arrived, fired-bellied toads (Bombina bombina) were calling. This is also a warm sensitive species, so a good sign, a motive for optimism. We waited there for the sun to set, and pretty soon we heard treefrog males calling in the distance. After a couple of hours, and a lot of wanderings through reeds and ponds ( and bios of the dosimeter), we managed to catch 13 males. Today it was specially tricky to find them into the reeds, they were not that exposed in the shore as in other nights. But we did it.
However, as the night advanced, temperature continued to drop, and when we leave the area, calling activity was almost ceased. We looked for frogs in another three localities in medium contaminated areas, but not a single frog was calling there. So, we headed back to our base in Chernobyl, hoping for something better tomorrow.
The plan now is to go back to the lab during the morning and process all the new frogs, and keep on looking to the weather in order to go to the field during the night and try to catch more frogs in three localities that we visited last year in medium radiation areas on the east bank of Pripyat river. Forecast, once again, is not good, cloudy during the day, with chances of rain, and co,d during the night. Just the opposite needed to activate warm depending species. Temperature during the night should be similar to last night, a bit on the limit. We will go anyway…
Apart from all the amphibians and birds, today we saw moose, red deer, probably a raccoon dog (too fast in front of the car to be sure), tons of hares, and a squirrel.
Moving during the day in mid radiation areas and, specially, sampling during the night in highly contaminated locations means that the total accumulated dose also raised today, from 58 microSv to 92, a total of 34 microSv. The plans now, if weather allows, are for moving across mid-low contaminated areas, so no big increases should be expected from now.