Monday, 27 April 2015

Cerkniško jezero & Javorniki forest

Some days ago I was on a pleasant trip to the Cerknica lake (Cerkniško jezero) with a group of university students. Our main subject was botany, but in a place like this, it was hard to stick only to plants. I must say that early in the morning I had a good feeling for the day: I woke up at home, to the sound of a singing Cuckoo Cuculus canorus and a trilling Wood Warbler Phylloscopus sibilatrix.
And it actually proved to be a very good day bird-wise. The wetland habitats of the lake itself produced the typical exciting mix that Cerkniško has to offer. A booming BITTERN Botaurus stellaris was heard for most of the day, while from the same reedbed habitat a LITTLE CRAKE Porzana parva was delivering its song. We also managed to see a RED-NECKED GREBE Podiceps grisegena in perfect breeding plumage. Cerkniško jezero is the only place in Slovenia where this species breeds.
Red-necked Grebe Podiceps grisegena

The water bodies held a nice big flock of Shovelers Anas clypeata and Garganeys Anas querquedula, while a male Goldeneye Bucephala clangula looked a bit out of place in this season. The reedbeds were quartered by several Marsh Harriers Circus aeruginosus, but most interestingly by tens of RED-FOOTED FALCONS Falco vespertinus. All over the lake and surrounding areas I've counted about 30-40 Red-footed Falcons. Cerkniško jezero is an important stop-over site for this species during migration. "Good days" in late April and May can produce flocks of several hundred birds.
Migrants were also represented with a few waders specie: Black-winged Stilt Himantopus himantopus, Wood Sandpiper Tringa glareola, Ruff Philomachus pugnax, Greenshank Tringa nebularia. Of the breeding birds we also had Sedge Warblers Acrocephalus schoenobaenus, Yellow Wagtails Motacilla flava, White Stork Ciconia ciconia, Peregrine Falco peregrinus, Fieldfare Turdus pilaris, Yellowhammer Emberiza citrinella and a Short-toed Eagle Circaetus gallicus hovering above the grasslands.

Botanising was mainly restricted to the forest edge, grassland and small woodlands, so the plants were mainly the typical representatives of the Dinaric forests of silver fir and beech (Abieti-Fagetum). I didn't have time to take many photos, so here are just some of the +60 species we had:
Aremonia agrimonoides
Paris quadrifolia
Cardamine bulbifera
Asarum europaeum - leaves (above) and the odd flower (below).
Myosotis sp.
Omphalodes verna
Beech Fagus sylvatica

In the late afternoon we made a small incursion into the mixed forests of Javorniki, above the lake. We heard two drumming THREE-TOED WOODPECKERS Picoides tridactylus and at the same time "flushed" a URAL OWL Strix uralensis while walking on a forest road. The owl was then seen two more times, once perched, once in flight (briefly), while a female Three-toed was observed drumming on a broken beech tree. It's the first time I see a Three-toed on a deciduous tree. It looked odd!
Watching the Three-toed Woodpecker
Supporting cast in the Dinaric forest included Grey-headed Woodpecker Picus canus, Bullfinch Pyrrhula pyrrhula, Cuckoo Cuculus canorus, Firecrest Regulus ignicapillus & Goldcrest R. regulus and a singing Tawny Owl Strix aluco in the evening. All in all an excellent day in the field!