Monday 24 July 2017

Rare birds & summer flowers

Summer is a quite slow and relaxed time and so is the processing of photos from field trips. In the last ten days or so we have been visiting some of the regular places, not far from home, without any great expectations or tagrets. In such a calm season like summer, you have to be happy with the small things: a few birds, lots of flowers, some insects and that's it. In this post we will again present a mixture of widlife encountered during our recent birding/botanising/butterflying. Areas we visited include: Snežnik, Trnovski gozd, Vipava valley and mostly the Karst.
We will start with our most interesting observation involving Lesser Grey Shrikes Lanius minor. This attractive songbird can be observed in just a few places in Slovenia. Unfortunately it is a very rare and endangered species, with less than 10 breeding pairs recorded in 2016 in the country. The majority are found in the Vipava valley where they form small breeding colonies in agricultural areas, on tall poplar trees Populus sp. Recently we visited the site and observed two birds - an adult and a juvenile (above). They were readily using the poles which have been placed by DOPPS's volunteers to encourage the species at the site. The poles, about 3 m high, are used as hunting perches by the shrikes, which feed mostly on grasshoppers, beetles, caterpillars and large insects. Let's hope this small population will in the future still resist at its traditional breeding site.
Another high quality observation involved Black Storks Ciconia nigra. Since 2010 we have been observing single birds or a pair during the summertime in a large forested area in the region of Ilirska Bistrica in western Slovenia. Given our numerous observations during the breeding season and the fact that the habitat looks appropriate, we suppose a pair must breed in the area. Moreover, last week we observed three individuals soaring together (photo above) indicating a possible successfull breeding. Unfortunately we were unable to notice enough details to confirm the bird's age, but it is quite probable that some were juveniles. Observations of Black Stork from western Slovenia, especially those in the breeding season, are very interesting. The species is a rare breeder and usually found in the lowland, eastern part of the country. Few other pairs are known outside its Pannonian strongholds. It is even rarer in the west of the country, where large undisturbed forests in the vicinity of lowland rivers and forest streams are lacking.
Our wandering took us to some forests as well, on the Snežnik plateau, where we had a daylight encounter with this Ural Owl Strix uralensis. Although it was perched high up in the canopy, the bird was very calm and allowed us to approach right under its tree.
This Tawny Owl Strix aluco, a common species throughout Slovenia, was hunting along a forest road at night, on the slopes of the Snežnik plateau. It is interesting to notice that the presence of Ural Owl usually excludes Tawny Owl because of competition for prey. Ural Owls usually inhabit more montane forests above a certain altitude, for example on plateaus like Snežnik, Trnovski gozd, Kočevski rog ect. On lower altitudes and the slopes of those plateaus, Ural is replaced by Tawny.
In the Snežnik forests we also stumbled across two Nutcrackers Nucifraga caryocatactes feeding on spruce seeds. This species can be seen in Dinaric and Alpine forests, but is nowhere very common. Moreover, in our experience, it is quite shy and can be located mostly thanks to its loud calls. Late summer and autumn is usually a good time to see one, as birds wander around more frequently.
Golden Orioles Oriolus oriolus are common birds, but most often heard than seen. The above bird is unfortunately not an attractive adult male, but rather a female/immature male (those that often pose for photos!). The species can be found in different types of broadleaved forests and fledged juveniles and families are quite noisy at this time of year. Enjoy them while you can, as in late August they will depart for Africa.
We thought we would publish another post dedicated to butterflies in the near future, but Lepidopteras seem quite thin on the ground at the moment. The butterfly diversity climax was in June, while now in mid summer we have to concentrate just on certain interesting species. One of them is the Scarce Large Blue Phengaris telejus (also Maculinea telejus) which we found on a wet meadow near Ilirska Bistrica. The species' life cycle is linked to a specific plant - great burnet Sanguisorba officinalis and to an interesting relationship with ants. Adult butterflies deposit the eggs on burnet and the caterpillars first feed on it. Later the caterpillars are taken by ants (Myrmica spp.) into their nests, where the caterpillar predates the ant's larvae. At end of their development, the adult butterflies emerge and leave the ant's nest. Due to this intricate relationship with ants and host plant, the Scarce Large Blue and other species from the genus Phengaris are some of the most endangered butterflies in Europe.
And now to botany! We will start with Gentiana cruciata, a scarce species growing on dry mountain meadows. It is the host plant of the Mountain Alcon Blue Phengaris alcon f. rebeli, an ecotype of the Alcon Blue Phengaris alcon. Photographed on the Slovenian Karst; we have recently seen it also on grasslands of the Snežnik plateau, where wasn't in flower yet.
The beautiful Gentiana lutea ssp. symphyandra on the southern edge of Trnovski gozd, where grasslands at this time of year are still nicely coloured and varied. In the Alps, the morphologically different subspecies vardjanii is found. The root of this imposing plant was once used to produce the "encijan", an alcoholic drink with a bitter flavour. Nowadays most of the species from the genus Gentiana are protected and collecting is prohibited.
Echinops ritro ssp. ruthenicus is a very attractive (and very spiky!) plant of karstic grasslands. The above where photographed on the southern edge of Trnovski gozd (in the first pic with Scabiosa graminifolia). In Slovenia it is only found in the west of the country, in the sub-Mediterannean region. Two similar, but taller species, Echinops exaltatus and Echinops sphaerocephalus also grow in Slovenia. Recently we have seen E. exaltatus near Ilirska Bistrica, where it is very common.  
Phyteuma scheuzcheri is common on rocky cliffs and slopes on the southern edge of Trnovski gozd. The most similar species to this is Phyteuma orbiculare, but for the sake of the reader, we'll avoid plant ID details!
Mid summer is the time of pinks Dianthus. In the Karst region, the most impressive is Dianthus monspessulanus (D. hyssopifolius), sporting the most elaborate petals. All pinks in Slovenia are protected. In western Slovenia most species are found on dry grassland. In the next photos are some other species that can be admired at this time of year around the Karst...
Dianthus sanguineus (also D. carthusianorum ssp. sanguineus)
Dianthus balbisii ssp. liburnicus is only found in the sub-Mediterranean region of western Slovenia. It is quite scarce and not so commonly seen as the two previous species.
Dianthus sylvestris can be found throughout Slovenia, usually more commonly on higher altitudes. In the Karst is only found on high-karst plateaus and mountains.
Dianthus tergestinus (D. sylvestris ssp. tergestinus), named after the town of Trieste (old name: Tergeste) and mostly found in the Classical Karst around the city, but also in some areas of Slovenia.
Two views on a patch of old conifer forest in Trnovski gozd, with large amount of standing and fallen dead trees. Crossbills Loxia curvirostra seem to be in a feeding frenzy at the moment as flocks assault Norway spruce Picea abies cones. Quite frequently some cones are "thrown" to the ground and we have risked several times to be hit by such spruce bullets!
Telekia speciosa is a large plant of the family Asteraceae (Compositae) that can grow two meters tall. It can be found in some forests of the Dinaric and Alpine region, usually favouring forest margins and clearings. The above photo was taken in Trnovski gozd, where the species is widespread, but nowhere very common.
Potentilla caulescens is an Alpine species growing also in Trnovski gozd, quite commonly on the wet rocky cliffs on the southern edge of the forest. 
Cyclamen purpurascens is a very common woodland flower. The first appear in mid summer and by autumn all are in bloom, colouring the forest floor. It is widespread in all regions of Slovenia. Some say it is a "harbinger of autumn"...