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I recently got back from the usual family vacation to Bulgaria with my wife and daughter. On visiting the in-laws in the town of Etropole, between 30th July and 3rd August I took 2-3 hours per day to walk in the surrounding forest. It was very sunny with temperatures close to 30 C in the shade and above that in the sun. It also hasn't rained for a long time so I was not hoping for much. I'm not going to go into the day to day details of my walks but rather give you a summary of what I found. As usual no great photography from me but I still hope you enjoy it. Here we go:

Just before I climbed the slope to the forest there was a stream full of small fish, mainly chub, and many Pelophylax ridibundus. Just in one spot, under a small bridge both Natrix natrix and Natrix tessellata were present, as well as some Podarcis muralis. I observed a young N. natrix foraging but curiously it was ignoring the easier to catch frogs and going for the faster and more agile fish. Ambitious little guy









Next on my route was the forest situated on a fairly big slope. Originally the forests in this area were beech forests but here these were replaced by a forest of big pines planted long ago for timber. As a result the forest is now more open with plenty of low ground vegetation such as grasses, stinging nettles, bramble, hawthorn bushes and more. Millions of grasshoppers, spiders and other invertebrates inhabit the forest floor. There are also some meadows varying in size. Both on the meadows and in the forest I found three syntopic lizard species - Lacerta viridis, Podarcis muralis and, a species new for me, Darevskia praticola. For some reason only females of L. viridis were seen...





























Continue to Part 2 => http://www.fieldherping.eu/Forum/viewtopic.php?f=13&t=2540&p=25541#p25541

Those unexpected finds are always the best. What you mentioned with the natrix, I have seen before. Interesting why though.

I look forward to the next bit

Thanks Tim. Yes, the unexpected finds are great!

As for the Natrix - I was wondering the same and hoped someone else might have more info on such behaviour.

have observed this behavior in Natrix natrix "often", like on Krk island, where young specimens have been hunting for Gambusia. Although there have been adequate sized ridibundus. Maybe the movements of the fishes are important?
btw, large Natrix started to catch larger ridundus, when the frogs start moving, and didnt react as long as the Pelophylax were resting on the surface.

Mario Schweiger wrote:Maybe the movements of the fishes are important?
btw, large Natrix started to catch larger ridundus, when the frogs start moving, and didnt react as long as the Pelophylax were resting on the surface.

I think you have a point here but I wonder why visual clues would be stronger for Natrix when they can certainly "smell" the frogs and know they are food. I've also seen videos of Natrix catching and eating frogs/toads that were static but only on dry land...Actually when I think about it all the photos, videos and live action of Natrix eating frogs was on dry land. Maybe they don't hunt them in the water at all?