Monday 20 September 2021

Back to the forest

After spending ten days in Dalmatia (Croatia) at the beginning of September (hopefully more on that soon in a trip report), we're now back in Slovenia, making the most of what autumn has to offer. In the past weekend we went looking for Three-toed Woodpecker Picoides tridactylus on the Snežnik plateau and also explored new areas we haven't been before. Forest reserves (where logging is prohibited) offer excellent possibilities for finding rare woodpeckers, as they hold larger amounts of dead wood compared to commercial forests. However most of these reserves are so small that birds are not always where one might expect. In the morning, despite working a nice mixed forest of beech Fagus sylvatica and silver fir Abies alba, with lots of woodpecker's signs, we only came across Grey-headed Picus canus and Black Woodpecker Dryocopus martius, while Three-toed eluded us. Nevertheless we were pleased to find a pair of Ural Owls Strix uralensis thanks to the insistent mobbing calls of Jays Garrulus glandarius that revealed the owls' location.

Forest reserves are marked with blue lines.
Red-belted Conk Fomitopsis pinicola - thriving on rotting conifers.
Pholiota sp.
Woodpecker's feeding signs on a dying silver fir Abies alba.
Ural Owl Strix uralensis

Around midday we changed location and worked the edge of another forest reserve, rich with silver firs and Norway spruces Pice abies that have been hit by several consecutive wind storms. Upon arrival some distressed behaviour by the local tits (Coal, Willow, Crested) caught our attention - they were alarming at something. We investigated and soon realised the source of all the panic was a beautiful Pygmy Owl Glaucidium passerinum sat nicely on a low branch in front of us! The tiny predator allowed some excellent views for a minute or so, before flying off in the thick conifers and starting to call. Later we heard a second Pygmy Owl in the same area, while a third was singing in the late afternoon in a managed forest in the Javorniki mountains. In autumn, at the time when leaves start to fall from the trees, Pygmy Owls have a distinct peak in vocal activity and sing even during the day. Thus, the end of September and beginning of October is perhaps the best time to observe & census this rare species of forest owl.

Pygmy Owl Glaucidium passerinum - Domen's point of view.
Pygmy Owl Glaucidium passerinum - Sara's perspective.

After the short Pygmy Owl intermezzo we were finally again on the search for our target species of the day - Three-toed Woodpecker. We began working the nice stand of decaying conifers, finding some interesting wildlife on the way. An accidental kick at a log on the ground resulted in a lovely discovery - under the piece of wood was curled a beautiful Alpine Salamander Salamandra atra. This is a moist-loving species and in places like Snežnik, where surface water is literally absent, this animal relies on the moisture it finds under logs, among rocks, in tree's cracks and in the moss. 

September is the peak time of Red Deer's Cervus elaphus rutting activity and the forests were echoing with the stag's rutting "calls". On a steep rocky slope we even spotted a nice stag with well-developed antlers that allowed some short views, before fleeing upslope. On a moss-covered trunk we also found some plucked feathers belonging to a Long-eared Owl Asio otus - it most probably fell victim to a Ural Owl.

Forest reserve with large amounts of dead conifer wood.
Moist forest full of moss, covering fallen trunks.
Alpine Salamander Salamandra atra
Red Deer Cervus elaphus
Feathers of Long-eared Owl Asio otus, probably preyed by a Ural Owl Strix uralensis.


Finally we were listening to some insistent "ciuk" calls delivered by an unknown woodpecker. Despite being in some perfect Three-toed Woodpecker habitat, we were once again surprised that the source of the sound was instead a female White-backed Woodpecker Dendrocopos leucostos ssp. lilfordi. As the two species have rather similar calls, we compared them on the phone and realised the female we were observing was sounding perfectly Three-toed-ish. In fact upon playing the Three-toed's calls, the bird reacted intensively, while it didn't care much about the White-back's playback. We already observed this behaviour a couple of other times, while playback-censusing Three-toed Woodpeckers in spring. In habitats that are good for Three-toed and where beech is also found, White-back is always a possibility. As we have observed many times, White-backs, despite being broadleaved-tree specialists, frequently use silver fir Abies alba for feeding (see pic below). In the end we also managed to locate a Three-toed Woodpecker in the same area: it was a rather dark-coloured and quite skulky female, feeding on a distant tree and not allowing a closer approach. But still, better than nothing!

White-backed Woodpecker Dendrocopos leucotos ssp. lilfordi
Three-toed Woodpecker Picoides tridactylus
Perfect decay stage of a silver fir for the needs of a hungry Three-toed Woodpecker.
Three-toed Woodpecker habitat with dead & decaying conifers.
An old stand of dead conifers, but unsuitable for Three-toed Woodpecker at the current stage (absence of bark).

Broad-leaved Spindle Euonymus latifolia
Warty-barked Spindle Euonymus verrucosa

Recently we also spent some time more locally in the Karst's woodlands & meadows around our home. In the last decades Red Deer Cervus elaphus have colonised much of the Karst (open areas scrubbing over and giving way to woodland) and nowadays we can actually enjoy the rutting season quite close to home. The other day we had a nice "wilderness stroll" with 6 species of woodpeckers and a Red Deer stag in full rut. Meanwhile the dry karstic meadows on the edge of the forest offered the year's last orchids - the tiny Autumn Lady's-tresses Spiranthe spiralis, as well as carpets of Autumn Crocus Colchicum autumnale. In the sky above we watched what was probably the last Short-toed Eagle Circaetus gallicus of the season - soon all will be heading to Africa, not returning before March next year.

Broadleaved woodlands on the edge of the Karst turning to autumn colours.
A window on the Karst.
Autumn Lady's-tresses Spiranthes spiralis
Autumn Crocus Colchicum autumnale
Short-toed Eagle Circaetus gallicus