Sunday 27 March 2016

Krakovski gozd - alluvial forest

Fritillaria meleagris (Snake's head fritillary), Krakovski gozd, 25th March 2016. A beautiful flower of wet meadows and alluvial forest that has become rare and threatened by the drainage of wetlands. Krakovski gozd, together with Ljubljansko barje (Ljubljana marsh) is one of the Slovene strongholds of this species.
Black Stork Ciconia nigra, Krakovski gozd, 25th March 2016. This bird was resting and preening in the middle of the main forest road through Krakovo forest. The area supports 2 to 4 breeding pairs of this rare species.
Pulmonaria dacica, Krakovski gozd, 25 March 2016. Very common flower in the Krakovo forest - a specialty of the area. In Slovenia inhabiting only alluvial forests of Quercus robur such as Krakovski gozd and a few others.
Gagea spathacea, Krakovski gozd, 25 March 2016. Another specialty of the area, inhabiting alluvial forests and wet woodlands.
Caltha palustris, Krakovski gozd, 25 March 2016. A common species in water ditches throughout the forest.
Lowland alluvial forest of English oak Quercus robur and European hornbeam Carpinus betulus (Pseudostellario-Quercetum & Pseudostellario-Carpinetum), Krakovski gozd, 25 March 2016. A large amount of dead and decaying trees is present in the forest, thus supporting a thriving population of woodpeckers and other cavity-nesting birds.
Middle Spotted Woodpecker Dendrocopos medius, Krakovski gozd, 25 March 2016. One of the largest breeding populations in Slovenia is found in the Krakovo forest. I had up to 6-7 individuals. Nearby the above bird was also a Ural Owl Strix uralensis!
Alluvial forest with English oak Quercus robur, Krakovski gozd, 25 March 2016.
Ranunculus ficaria, Krakovski gozd, 25 March 2016.
Pulmonaria dacica & Anemone nemorosa, Krakovski gozd, 25 March 2016. These species create vast white & blue carpets all over the forest's floor.
Ranunculus auricomus, Krakovski gozd, 25 March 2016. Another very common flower in the Krakovo forest, loving wet forest and water margins.
Veratrum album & Anemone nemorosa, Krakovski gozd, 25 March 2016.
Chrysosplenium alternifolium (with Pulmonaria dacica), Krakovski gozd, 25 March 2016.
Anemone nemorosa, Krakovski gozd, 25 March 2016.
Green sprouts of Iris pseudacorus, with Caltha palustris (in the back), Krakovski gozd, 25 March 2016. The forest is full of flowering Irises later in the season - see this post.
Oxalis acetosella, Krakovski gozd, 25 March 2016.
Leucojum vernum, Krakovski gozd, 25 March 2016.
Alluvial forest with Caltha palustris, Krakovski gozd, 25 March 2016.
White Stork Ciconia ciconia, Dobrava pri Škocjanu (Krakovski gozd area), 25th March 2016. The first storks of the year!

On Friday I visited the fabulous Krakovski gozd (Krakovo forest), east of Novo Mesto in south-eastern Slovenia. Krakovski gozd is the largest area of uninterrupted lowland alluvial forest in Slovenia. It has a special conservation value due to the rarity of this kind of habitat in Slovenia. 
The most important bird species are Middle Spotted Woodpecker Dendrocopos medius, Collared Flycatcher Ficedula albicollis, Black Stork Ciconia nigra, White-tailed Eagle Haliaeetus albicilla, Ural Owl Strix uralensis and Lesser Grey Shrike Lanius minor (in the nearby farmlands). The first two species have very high breeding densities in the forest, thus they are quite easy to observe.
On the botanical front, the most characteristic (and rare on a national level) plants include: Fritillaria meleagris, Pulmonaria dacica, Gagea spathacea, Viola uliginosa, Epipactis nordeniorum.
For more about Krakovski gozd see this post.

Monday 21 March 2016

Middle Spotted Woodpecker census

Middle Spotted Woodpecker Dendrocopos medius on sessile oak Quercus petraea; Slovenian Karst, February 2015.

Yesterday, together with a couple of friends and colleagues from DOPPS (BirdLife Slovenia), I carried out an organised census of Middle Spotted Woodpecker Dendrocopos medius on the Slovenian Karst. We accurately investigated the wider area where I usually observe this species and tried to find new breeding areas. Using the playback method, along trasects, we counted 8 territorial Middle Spotted Woodpeckers on a relatively small area. The results show that, as expected, this species is commoner than thought in some higher parts of the Karst. It mostly inhabits hills covered with older oak stands (Quercus petraea, Q. cerris) on sunny locations. A few other trasects are to be censused in the coming weeks, so perhaps we'll add new locations to the distribution of this species.
Most of the population of Middle Spotted Woodpecker in Slovenia is concentrated in the eastern and south-eastern part of the country. It is a common species in lowland oak forests such as Krakovski gozd or the alluvial forests by the river Mura (at both sites it is a qualifying species for Natura 2000). Part of the Slovenian population also inhabits the Dinaric forests of Kočevje, where oddly there are few oak stands, on which the species greatly depends. In western Slovenia the species is rare and the population we discovered is quite localised to just a suitable area of oak forest. Perhaps in the future, with the aging of the woodlands and scrubland now covering the Karst, the species will colonise new areas of mature forest. A major threat to Middle Spotted Woodpecker is the cutting of large oak trees (usually older than 80-100 years) on which the species depends for foraging and nesting. Tree logging in some Slovenian forests have already affected populations in the east of the country.

Middle Spotted Woodpecker habitat on the Slovenian Karst, March 2016. The predominant tree species are Quercus petraea, Q. cerris and Fagus sylvatica.
Signs of woodpecker's nesting holes, Slovenian Karst, February 2015. The area is important for many other species of Picids, including Grey-headed Picus canus, Lesser Spotted Dendrocopos minor and Black Woodpecker Dryocopus martius which are all quite common.
Erythronium dens-canis (dog's tooth violet), Slovenian Karst, 18th March 2016. Now in full bloom all over the woodland floor - an amazing spectacle of pink colours popping out from the leaf litter.

Monday 14 March 2016

Life on the cliffs

Wallcreeper Tichodroma muraria, Osp cliffs, 11th March 2016 (pics by Sara Cernich). The limestone cliffs of Kraški rob (Karst edge) at Osp are perhaps the most reliable site in Slovenia to see this species in winter. Recently I made a collage video of the Wallcreepers on the Karst - see here (watch in HD - 720p). Also present at the Osp cliffs were the resident Peregrine Falco peregrinus and Blue Rock Thrush Monticola solitarius.
Moehringia tommasinii, Osp cliffs, 11th March 2016. This is an endemic plant of Kraški rob (the Karst edge) between the Glinščica valley/Val Rosandra in Italy and Istarske toplice in NW Croatia. In Slovenia, the most reliable site to see it are the cliffs at Osp.
Primula auricula, Škocjanske jame, 11th March 2016. An alpine species, being a glacial relict on the Karst. Here it is found at only two localities: the sinkholes of Škocjanske jame (Škocjan cave - UNESCO site) and Orlek. In such habitats it grows on north-exposed, vertical limestone cliffs, which are wetter and colder than the surrounding habitat and thus resemble the microclimatic conditions in the alpine region. More about Primula auricula in this post.
Two views of Velika dolina sinkhole at Škocjanske jame, 11th March 2016. The microclimatic conditions in this doline support an amazing mix of alpine and mediterranean flora. On the bottom of Velika dolina (formed by the collapse of a cave's roof) flows the river Reka which here sinks underground and continues its way to the Adriatic sea as an underground river. It reappears 33 km further west, near Devin/Duino (Trieste, NE Italy) as the river Timava (same river, different name). After only 2 km, the Timava meets the sea near the wetland of Lisert. What about the river's origin? The Reka/Timava has its springs on the Snežnik plateau!
Adiantum capillus-veneris, Škocjanske jame, 11th March 2016. At the entrance of one of the caves in Velika dolina grows this amazing species. It is a rare fern with a paleotropic, subtropic and mediterranean range, reaching its northernmost distribution edge in Slovenia. It favours wet and warm limestone rocks. The special microclimate of the caves, guarantee a constant air temperature (above freezing) throughout the year and thus supports this species.
Polypodium interjectum, Škocjanske jame, 11th March 2016. This fern (a relative of P. vulgare) is a typical inhabitant of the Karstic dolines, where it grows quite commonly.
Anemone ranunculoides (top) and Hacquetia epipactis, Škocjanske jame, 11th March 2016. The nemoral flora on the bottom of Velika dolina was at its best, with species like Isopyrum thalictroides, Primula vulgaris, Hepatica nobilis, Cardamine enneaphyllos, Corydalis cava, Lathraea squamaria in great numbers.
Scilla bifolia, Škocjanske jame, 11th March 2016.
Hepatica nobilis, Škocjanske jame, 11th March 2016 (pic by Sara Cernich).
Isopyrum thalictroides, Škocjanske jame, 11th March 2016.
Crag Martin Ptyonoprogne rupestris, Monte Grisa (Trieste, Italy), 14th March 2016. One of the 3 Crag Martins seen flying above the limestone cliffs. Only the third record for the area. On Friday 11th March I also had my first 4 House Martins Delichon urbicum of the year in Trieste.
Euphorbia wulfenii, the Adriatic sea and the town of Trieste (in the back); Monte Grisa (Trieste, Italy), 14th March 2016.
Euphorbia wulfenii, Monte Grisa (Trieste, Italy), 14th March 2016. A common species on the limestone cliffs by the coast of Trieste. This amazing plant, which is in bloom at this time of year, has a balkanic range and reaches it north-westernmost edge of distribution right here near Trieste.
Polypodium australe (P. cambricum), Monte Grisa (Trieste, Italy), 14th March 2016. This is another interesting fern, growing on warm, sunny limestone cliffs of southern Europe, however it is never exposed to full sun. Thus it is found in crevices and crags that remain in shade for most of the day.