Friday 20 November 2020

Preparing for the winter

As autumn slowly turns into winter, the mountain forests of the Dinaric region fall incredibly silent and empty. Above 1000 metres most of the deciduous trees already shed their leaves by the end of October, leaving the forest to a dull grey colour. However wildlife is still around and can be observed with a bit of luck and knowledge. At this time of year the conifer stands are usually richer with birds, whereas in the beech forests, total silence is broken only by the occasional mixed flock of birds that appear as if by magic and quickly vanish again. During recent fieldwork in the Snežnik mountain range we came across several of the (usual) interesting birds inhabiting the altitude between 1000 and 1400 metres a.s.l.. In a karstic dolina (sinkhole) covered by Norway spruce Picea abies we tracked down a confiding male Three-toed Woodpecker Picoides tridactylus feeding on fallen conifer trunks (see video below). This type of feeding behaviour seems to be common especially in males which like to feed very low down, sometimes even on the ground. Interestingly, we noted the same type of behaviour in male White-backed Woodpeckers Dendrocopos leucotos, whilst females tend to feed higher up on trees and on side branches. The latter species was (is) actually our main survey target and this time we managed to track down and observe a rather mobile female White-back, feeding on contorted beech trees close to a Great Spotted Woodpecker D. major and within a mixed flock of small forest birds. In the same area a surprisingly large flock of Bramblings Fringilla montifringilla was feeding on the ground on fallen beech mast, a particularly abundant source of food this year. Several hundred Bramblings were "streaming" through a small ridge in the forest for several minutes. Overall this autumn the species seems to be very numerous in mountain beech forests. Given the abundant beech crops, another winter invasion such as the one in 2019 wouldn't be surprising. Finally among interesting birds we also heard several hooting Ural Owls Strix uralensis among which we also observed a male at close quarters.

Three-toed Woodpecker Picoides tridactylus, male.
The edge of a forest reserve, marked with a double blue line.
White-backed Woodpecker Dendrocopos leucotos, female.
Ural Owl Strix uralensis
Brambling Fringilla montifringilla, male (above) & female (below).

Other forest animals are also still active, especially in the conifers, such as the several Red Squirrels Sciurus vulgaris we observed gathering food on the woodland floor or the noisy herd of Wild Boars Sus scrofa that we surprised rustling in the leaf litter. Red Deer Cervus elaphus are basically everywhere although their presence can be noticed only by their signs. Brown Bears Ursus arctos are also still active, as the numerous droppings and feeding signs testify, although some of them might have already moved to their winter dens.

Red Squirrel Sciurus vulgaris

A Brown Bear Ursus arctos has been digging hard and turning stones.
A probable bear's den, under a rocky block, with signs of turned stones and dug up earth.
Brown Bear's claw signs on a trunk crossing a wildlife "corridor".
A wildlife "corridor" where deer, boars and bears have "consumed" a fallen trunk by passing over it (and through it) repeatedly.


Meanwhile lower down in the Karst around Sežana we've been visiting our usual circuits within short reach from home. Given the fine and sunny autumn weather with northeasterly winds we expected to see some good migration of Common Cranes Grus grus. However the migration of this species over western Slovenia has been very weak so far. Nevertheless on the 8th of November we saw a flock of 4 individuals arriving from the Razdrto area and migrating above the Divača-Sežana area. Next, on the 17th we saw 3 small flocks, all from the top of a small panoramic hill behind our house: 6 passed low above our head, 16 flew above Lipica and about 20 were seen very distantly, somewhere above Dutovlje-Komen. All flocks were heading westwards as typical for this season. Hopefully more larger flocks will follow in the coming weeks.

As lately we've been spending so much time indoors in front of the pc (smart working ect.), we've also been out on walks around home more often than usual. The discovering of hidden wild places that we initiated during the spring lockdown therefore continues. After our fantastic encounter with the Golden Jackal Canis aureus (see previous posts) we had several more sightings of this species. One day as we were setting a camera trap in the vicinity of the site where we saw this, a Jackal appeared out of nowhere and approached us, down to 10 metres, before realising our presence and fleeing. The camera trap results have been of course very productive. Another Jackal was seen some days earlier, while we were scanning a scrubby hill, where we also spotted two male Red Deer Cervus elaphus - another increasingly common mammal in the Karst, but more typical of montane forests. Among birds there were the usual multiple encounters with Middle Spotted Woodpeckers Dendrocopos medius as well as all the other commoner woodpeckers and Common Treecreeper Certhia familiaris (always an interesting find in the Karst). During a short vis migging session we also had the first Hen Harrier Circus cyaneus of the season (a nice male), migrating over the Karst. 

A couple of days ago we also made an afternoon walk on the hill called Veliki Medvedjak (473 m), very close to Sežana and right on the border with Italy, where we enjoyed a superb view over most of the Karst, the western part of Slovenia and north-east Italy. Walking back in the evening, a hooting Eagle Owl Bubo bubo rounded up our walk perfectly. We certainly can't complain about our local patch!

Common Crane Grus grus
Golden Jackal Canis aureus in the field (above) and on camera trap (below).

Red Deer Cervus elaphus - young male; above together with a stag (in the right corner).

Thermophilous woodland with limestone screes - habitat of Golden Jackal and Red Deer in the Karst.
Beech Fagus sylvatica
Basket Stinkhorn Clathrus ruber
Cool deciduous woodland on flysch in the Karst - from the outside...
...and inside.
View over the town of Sežana from Veliki Medvedjak (473 m), looking east.
Mt. Snežnik with its plateau is visible in the background.
Snežnik's summit (1796 m) sticking from behind the Sedovnik hill (575 m) above Sežana.
The "Sežana plain" with the villages of Orlek (far right) and Lipica (far left). The large hill in the centre is Kokoš (670 m), while the mountain in the distance is Slavnik (1028 m).
View east from Veliki Medvedjak hill.
A look towards Primorska's main landmark - Mt. Nanos (1262 m) with the village of Štorje in the foreground.
View north over the Karst of Komen (foreground) and the Trnovo forest plateau in the background.
The iconic village of Štanjel on the edge of the Karst and the mountains on the Trnovo plateau: Mt. Čaven-Mala Gora (1032 m) and the Golaki Mts. (1495 m).
Another look north, behind the Trnovo plateau with the imposing mount Krn (2244 m) in the Julian Alps.
Mt. Triglav (2864 m) - Slovenia's "father", this time seen from Strunjan on the Adriatic coast.
Sunset from Medvedjak, over the Trieste Karst and towards the Adriatic sea.

Thursday 5 November 2020

Karstic Golden Jackal

The Golden Jackal Canis aureus is a quite recent and spontaneous coloniser of central Europe, originally spreading west from SE Europe and the Black Sea area (check this article). As in several other countries, the species is becoming increasingly common also in Slovenia, where strong populations are already well-established, especially in the Primorska region in the west of the country (see the species' distribution in Slovenia). The Karst is one of its main strongholds and howling "packs" can be frequently heard around villages in the evenings. Apparently we also have several nuclei in our home area in the Karst around Sežana as there are some places where we hear them on a regular basis. Some weeks ago, while driving on the motorway near Sežana, Sara spotted a Jackal in a small clearing by the motorway's fence. The meadow happens to be a few hundred metres from the nearest motorway exit and has an easy access through a gravel road. On that occasion Sara rushed to check if the Jackal was still there, but with no luck. Today around 11.30 am the same scene repeted to Domen: he spotted a (the?) Jackal from the motorway, roving on the very same meadow. Shortly afterwards he was on the gravel road overlooking the meadow; this time the Jackal was still there and allowed about two minutes of observation from the car, at a distance of about 100 metres, before it disappeared in the karstic scrubland. It was enough to take a few shots and record the short video above. An added bonus to the amazing scene was the beautiful backdrop of autumn-coloured Smoke-bushes Cotinus coggygria, so typical of the karstic scrubland at this time of year. 
Back in 2019 Domen had another close encounter with the species in the Karst (see blog) and given the rapid expansion and great adaptability of the species, we can probably expect such encounters to become a regular event in the near future.

Tuesday 3 November 2020

Forests of the high & low Karst

Autumn is a beautiful time to enjoy the tranquility of the vast Slovenian forests. In the last two weeks and following our super-exciting trip to Snežnik, we visited this mountain's forests two more times. The main aim was to explore some seldom-visited areas, checking for potential good habitats & territories of White-backed Woodpecker Dendrocopos leucotos, for a forthcoming study we'll be doing on the species next spring. While trekking through remote areas of beech forest (between 1100 and 1400 metres a.s.l.) we found some amazingly wild places and came across some excellent habitat for this rare woodpecker. On both visits we had several White-backs (2-3 individuals per visit), however all proved pretty elusive, shy and extremely mobile. The most common give-away of their presence was their characteristic soft call, however, difficult to follow due to the extremely rocky and sometimes steep terrain. On one occasion we also came across an odd Lesser Spotted Woodpecker Dendrocopos minor, an extremely unusual bird in a beech forest at 1400 metres. Given the fact we saw it arriving in flight over a forest clearing on a mountain top, the bird might have been on migration. We don't really remember ever seeing a Lesser Spotted so high up in the mountains. Another interesting and casual find was a female Three-toed Woodpecker Picoides tridactylus that awaited us at the end of the day, in a conifer stand where we parked the car. The moment was too brief for any photos. On both visits we also heard several singing Ural Owls Strix uralensis (2-3 individuals per visit), but all proved elusive. Now that beech trees have already lost their leaves, it has become increasingly difficult to find and see birds at higher elevations. Mountain forests are somehow emptying and falling silent, except for the odd flock of roving birds, that sometimes hosts more interesting species. Bramblings Fringilla montifringilla in particular seem to be common this autumn. Despite the general silence and absence of animals, their signs are everywhere, especially Red Deer's Cervus elaphus tracks and droppings. Brown Bears Ursus arctos (such as this one :-)) are also still active and signs of their presence are frequently encountered in the form of droppings on the path, footprints in the mud or even claw scratchings on trees. We found some interesting scratches on the wooden walls of a small forest hut - a young bear was probably trying to break in, looking for food.

The beautiful spectacle of autumn colours is now visible only in beech forests at lower elevations (below 1000 metres).
Where managed forest gives way to a forest reserve, dead trees stand out.
White-backed Woodpecker Dendrocopos leucotos ssp. lilfordi (male).
A White-back's characteristic sign - a "shaved" tree.
Lesser Spotted Woodpecker Dendrocopos minor, an anusual sight in mountain forests.
Typical habitat of White-backed Woodpecker in Slovenia.
Ural Owl Strix uralensis
Large quantities of dead beech timber in a forest reserve.
Tinder Fungus Fomes fomentarius
Fresh feeding signs of Black Woodpecker Dryocopus martius.
One of the several drinking and bathing puddles in the forest. We found signs of Red Deer and Brown Bear on this one.
This impressive centenary Sycamore Acer pseudoplatanus had a completely hollow trunk.
Rocky outcrops such as these are a common feature in Snežnik's forests.
The karstic terrain on Snežnik is dotted with a multitude of larger and smaller dolinas, some of them inaccessible and forgotten - excellent places for finding bears during the day!
A dolina with the typical temperature inversion, with Norway Spruce Picea abies and Mountain Pine Pinus mugo growing on the bottom.
On top of one of the panoramic summits in the forest.
Mt. Snežnik (1796 m) is always within reach.
A forgotten forest hut in a remote area.
Brown Bear's scratches on the hut's walls.

Given the recent sanitary restrictions (now in act over most European countries), in the free time we've been concentrating more on our local area, the Karst around Sežana. A few days ago the autumn colours were still in full swing in the thermophilous oak woodland that we call our local patch. Logically oak trees (and the odd beech) at lower elevations loose their leaves a few weeks later than higher up in the Dinaric forests. We were glad to catch up with a pair of Middle Spotted Woodpeckers Dendrocopos medius, after several months from our last encounter with this lovely (and one of our favourite) species. An individual showed really well when feeding in the sun-drenched golden canopies of oaks. Minutes later we were surprised by a Griffon Vulture Gyps fulvus catching a thermal above a small clearing on the top of a wooded hill and passing a few ten metres above our heads. One late afternoon we also checked the site of our local Ural Owls Strix uralensis and were very happy to spot the pair exactly where we expected. Apparrently they didn't move much since spring.

Middle Spotted Woodpecker Dendrocopos medius
In the habitat of Middle Spotted Woodpecker.
Ural Owl Strix uralensis
The "forest gate", with the Turkey Oak Quercus cerris on the right, probably being the largest specimen of this species in the Karst.
A sunny panoramic paradise in the middle of the forest.
Griffon Vulture Gyps fulvus
European Smoke-bush Cotinus coggygria
Wild Service Tree Sorbus torminalis
Bosnian Maple Acer obtusatum, a locally common (Balkan) species in the Primorska region.
European Spindle Euonymus europaeus
Wild Peony Paeonia mascula, seedheads of a plant featured in this post.
Moon rising behind Mt. Nanos in the late afternoon.
Among northern migrants, some days ago we had the season's first RedwingsTurdus iliacus, while now we're waiting to see the first Cranes Grus grus moving south. Today some larger flocks have been spotted over Slovenia, so we expect a major passage in the coming days. Stay tuned.