Thursday 29 March 2018

Awakening forests

Spring is making a slow appearence in the Slovenian forests. The Karst, in western Slovenia, being rather termophilous, is quite alive with woodland flowers and bird songs. On the other hand, the season in the Dinaric forests of the Notranjska region is very late, with a layer of up to 30 cm of snow in the areas above 700 m.a.s.l. However, some animals and flowers are waking up in this cold region too. Last week we've visited the Cerknica lake and surrounding areas as well as completed a few more transects for the census of Middle Spotted Woodpecker Dendrocopos medius in the Karst.

Brown Bears Ursus arctos are waking up from the winter sleep and are wandering around the snow-covered forests of Notranjska. We found the above tracks, of at least two bears, on a small glade by the forest road that circles lake Cerknica. This video shows the season's first Brown Bear at the bear-watching hides in Loška dolina.

Whilst driving around lake Cerknica this fantastic Black Stork Ciconia nigra was spotted circling above the road. The species has just returned from Africa and will stay in Slovenia throughout summer to breed in some quiet forests. There's at least one pair breeding somewhere around lake Cerknica and birds are regularly seen feeding on the lake in spring and summer. Their commoner cousins, White Storks Ciconia ciconia have returned too - we observed one pair in the fields by the lake.

The forest floor in the Dinaric mountains is still snow-covered and vernal blooms are still quite poor. But one species in particular, the Christmas Rose Hellebrous niger, is very prominent in patches of snow-free leaf litter, especially close to the roads.

The temporary, karstic lake of Cerknica is full of water in this season. The lake's surface area now covers almost completely the Cerknica plain (polje) and the dozens of sinkholes spread around the lake are delivering a heavy load of water (second pic). Melting snow in the Javorniki hills and heavy spring rains are the main source of water to this intermittent lake. By mid-summer the lake will (should) be almost completely dry as the water will have flowed back into the same sinkholes. In the meanitime, many migrant waterbirds are exploiting the vast water bodies.

This small but very showy group of Garganeys Anas querquedula was in a feeding frenzy in a puddle on the Cerknica plain. On the lake itself there were several tens of other Garganeys, as well as Pintails Anas acuta, Shovelers A. clypeata, Wigeons A. penelope and still some wintering Goldeneyes Bucephala clangula.

The beautiful Dog's-tooth Violets Erythronium dens-canis are now in full bloom. The above were photographed in the Karst, where the species is not very frequent as elsewhere in Slovenia. However densities are quite high in some karstic oak woodlands with acidic soils.

Hacquetia epipactis is also carpeting the forest floor at the moment. It is found in woodlands throughout Slovenia, but more commonly in those with oaks Quercus sp. and hornbeam Carpinus betulus. Its "flower" is actually a pseudanthium - a group of many small flowers (the yellow ones) forming a single flower-like structure.
Mezereon Daphne mezereum is quite scarce in Karst's woodlands, but widespread elsewhere in Slovenia. The small pinkish flowers appear well before the leaves and grow directly out of the stem. The whole plant, including flowers and berries, is very toxic.

This short video was filmed in the Karst yesterday and shows a male Black Woodpecker Dryocopus martius entering a roost hole in the evening. Turn on the volume and listen for the bird's drumming at the beginning. Video also on our YouTube.

And for the end, yet another karstic Middle Spotted Woodpecker Dendrocopos medius during a recent census. We simply can't get enough of them! Can you? :-)

Tuesday 20 March 2018

Middle Spotted Woodpecker census

March is the time of year when the forests come alive with the sounds of territorial woodpeckers. Calm and sunny days are excellent for doing censuses, especially in the lowland snow-free areas of Slovenia. One such census is that for Middle Spotted Woodpecker Dendrocopos medius, a Natura 2000 qualification species at several sites in eastern Slovenia. As such it is monitored by DOPPS - BirdLife Slovenia on a yearly basis, in the lowland forests of Krakovski gozd and along the river Mura. Since the species was (is?) considered rare in western Slovenia, a few years ago, we began with some "investigation monitoring" in the wider area of the Karst. With the help of DOPPS we prepare the census transects and then, with the help of volunteers, carry out the playback-method census (playing the species' calls on tape and awaiting for response). Since 2016 our knowledge of the species' distribution in western Slovenia has widened. Now we can say that the Middle Spotted Woodpecker in the Karst is more widely distributed than we previously thought.
This year's census is still being carried out, but for now we have already confirmed 7 Middle Spotted Woodpeckers, 4 of them in a new, previously uncensused area. Males at this time of year are very territorial and frequently "sing" spontaneously. Listen for their typical spring "mewing" song in this short VIDEO we made recently. For more about Middle Spots in the Karst see this posts and this video (watch HD).

The good thing about spring censuses is that generally, in a good Middle Spot habitat there are also all the other woodpecker species: from the very common Great Spotted Dendrocpos major and Green Picus viridis, to scarcer Lesser Spotted D. minor, Grey-headed Picus canus and Black Woodpecker Dryocopus martius (above - a male).
To our great surprise, during a census on the 14th of March we also flushed this Hoopoe Upupa epops from a gravel road in some vineyards. This colourful bird usually returns from its wintering in Africa at the beginning of April. However in recent years the first Hoopoes are sometimes seen much earlier, like the individual we observed. It was certainly our earliest Hoopoe ever and an unexpected surprise.
The beautiful Dog's-tooth Violets Erythronium dens-canis are adorning the leaf litter in some woodlands around the Karst. This overall scarce flower can grow quite numerously on deep, wet soils in the flysch hills of western Slovenia. Their peak flowering time is usually the end of March, but this year, due to heavy snowfalls and low temperatures, the blooming season of many plants will be postponed.

Fire Salamanders Salamandra salamandra take advantage of the early spring rains and melting snow to emerge from hibernation. They are common throughout Slovenia, but usually seen only in wet weather or in permanently damp places. This individual was about 8 cm long.

On sunny days, hibernating butterflies emerge too. This Large Tortoiseshell Nymphalis polychloros is one of the typical early-spring Lepidoptera on the wings. At the same location there were also several Brimstones Gonepteryx rhamni and Admirals Vanessa atalanta.

Tuesday 13 March 2018

"Uu-h" - it's spring!

Early March is the best time of the year to catch up with Eagle Owls Bubo bubo as the males are very vocal and easily detected. The species is considered rare in Slovenia, with about 100-150 known breeding localities. Most of the sites are found in the karstic region of western Slovenia, while smaller numbers also live in northern and eastern Slovenia. The breeding habitat is usually represented by limestone cliffs with a southerly exposition, rocky slopes and quarries. During the last 20 years DOPPS - BirdLife Slovenia has been organising a traditional spring census of Eagle Owls in the Karst, aimed at counting as many singing males as possible. In one single evening, up to 100 or more people, divided in groups, check the owl's presence at around 40 locations across the Karst. The count is made at dusk, when the volunteers wait quietly for the very characteristic "uu-h", uttered by the male Eagle Owl. Last weekend we attended the census and were lucky to confirm the presence of the owl at our site...

The male Eagle Owl was holding a territory in a quarry and was singing in full view on the top of a pine. Later also its female joined with the singing, but for a short time. The whole singing is usually quite short, lasting only some minutes or maybe half an hour. On the census evening only 9 other sites had singing Eagle Owls.

A few days later we were again watching a male Eagle Owl at dusk, this time at the Karst edge. This bird was even more showy than the previous as it sang in full view for no less than 45 minutes. The light was fading fast, so taking proper photos was very tricky. In the second photo (above) note the white throat-patch, visible when the bird sings and puffs its throat feathers. 

Apart from Eagle Owls, in the previous days we also enjoyed some early-spring birdwatching at the Škocjanski zatok Nature Reserve (above), seeing among other things, our year's first Swallows Hirundo rustica and an Alpine Swift Apus melba. A noisy flock of Common Cranes Grus grus passed high above our heds, while other interesting birds included Garganey Anas querquedula, Little Ringed Plover Charadrius dubius, Mediterranean Gull Larus melanocephalus, Ruff Philomachus pugnax, Crested Tit Lophophanes cristatus (new species for the site!) and a Ferruginous Duck Aythya nyroca x Pochard Aythya ferina hybrid. The above drake Shoveler Anas clypeata was feeding a few meters in front of a hide.

Warmer temperatures are slowly melting the snow-covered woodland floor and vernal flowers are starting to emerge at large. Some woodlands in the Karst are already carpeted with colourful blooms. Here are some that we found recently...

Hepatica Hepatica nobilis (with Primrose Primula vulgaris in the lower pic)

Snowdrop Galanthus nivalis

Hacquetia epipactis

Alpine Squill Scilla bifolia

Isopyrum thalictroides

Wood Anemone Anemome nemorosa

Lungwort Pulmonaria officinalis

Spring Crocus Crocus vernus

Crocus reticulatus

Honey Bee Apis mellifera collecting nectar on willow Salix flowers.

Tuesday 6 March 2018

Early spring in Istria

After the strong spell of cold weather that hit central Europe recently, most of continental Slovenia is still under a thick layer of snow. Being heavily bored by this year's long and snowy winter, we decided to make a trip to some warmer parts of the northern Adriatic. So on Sunday we set for the Mirna river valley in Istria (NW Croatia) about 10 km from Slovenia's southwestern border. Istria is much warmer than most of Slovenia and has a more Mediterranean climate too. Even winters are mild and usually lots of birds "escape" the cold from areas farther north, to gather at such sites as the Mirna valley. Needles to say, also some of the wildlife found in Istria is typically Mediterranean and is usually rare or absent from Slovenia. Examples among breeding birds include Black-headed Bunting Emberiza melanocephala, Roller Coracias garrulus, Spanish Sparrow Passer hispaniolensis and Red-rumped Swallow Cecropis daurica

Our trip started with a typical winter scene. In the bay at the river Mirna's estuary there was a rough sea with 3 Slavonian Grebes Podiceps auritus, 10 Black-throated Divers Gavia arctica, 15 Common Gulls Larus canus and several Black-necked Grebes Podiceps nigricollis (some in breeding plumage). 
Fortunately some spring sightings followed soon...

Among the very welcome early-spring migrants were several Garganeys Anas querquedula; up to 10, swimming on the river Mirna (above) and in the lagoon at its estuary. The first migrant Garganeys appear at our wetlands in the very first days of March, while larger numbers follow later, till the end of April. Small numbers stay throughout summer to breed at quiet and undisturbed wetlands. 
In the estuary's lagoon there were also several other species of wildfowl, including numerous Wigeons Anas penelope, Teals Anas crecca, some Pintails Anas acuta and about 20 Shelducks Tadorna tadorna. On the flooded fields along the river, some large flocks of Lapwings Vanellus vanellus (several hundreds) contained the first returning Ruffs Philomachus pugnax (some in breeding plumage), two Black-tailed Godwits Limosa limosa and 3 Curlews Numenius arquata.

A brief jump back into winter and we were watching this beautiful male Merlin Falco columbarius, keeping an eye on a nearby flock of Skylarks Alauda arvensis and Meadow Pipits Anthus pratensis. This small, northern falcon is a scarce winter visitor at our latitudes and is usually found in lowland areas where flocks of small birds gather. The extensive fields in the Mirna valley are an excellent place to see this species.
Among other interesting raptors we also observed a female Goshawk Accipiter gentillis, 3 Hen Harriers Circus cyaneus and a Marsh Harrier Circus aeruginosus.

On the limestone cliffs of Istarske Toplice, in the upper part of the Mirna valley, we observed another typical winter bird, a Wallcreeper Tichodroma muraria. It was too distant to take photos, so this time we can only show you its habitat. By the beginning of April most of the wintering Wallcreepers at karstic cliffs will have departed for their alpine breeding grounds.

Among the few plants in flower at this time of year were these beautiful Broad-leaved Anemone Anemone hortensis. We found them on a dry rocky grassland on a limestone hill overlooking the Mirna valley. Being a typical Mediterranean species, this anemone is widespread in Istria (and Croatia in general), but very rare in Slovenia, with only one known locality in the southwest of the country. 

On the dry grasslands some other plants were making an early appearence, including Lesser Celandine Ficaria verna (Ranunculus ficaria) and the leaf-rosettes of an Ophrys species, most probably Early Spider Orchid O. sphegodes.

This small Yellow Star of Betlehem that we found on the dry grassland is probably Gagea pusilla (we are still processing the ID), a relative of the common Gagea lutea, usually found on damp soils in woodlands.

Prickly Juniper Juniperus oxycedrus is a common shrub on the termophilous hills above the Mirna valley and a typically Mediterranean plant. Note that the fruits are not purple-blue as in the Common Juniper J. communis, but rather reddish and quite larger.

The shrub layer in woodlands was adorned by the flowers of Cornelian Cherry Cornus mas, a common shrub throughout Istria and Slovenia. However those in Istria were the first flowering specimens we saw this year; in Slovenia the weather was still too cold to make them bloom.
Spring Crocus Crocus vernus in a wet woodland by the river Mirna, where plants like Lungwort Pulmonaria officinalis, Wood Spurge Euphorbia amygdaloides, Primrose Primula vulgaris and Lesser Periwinkle Vinca minor were also in bloom. 

Among other birds on the fields of the Mirna valley was also this Stonechat Saxicola torquatus, a Great Grey Shrike Lanius excubitor, some Corn Buntings Emberiza calandra and a huge flock of Starlings Sturnus vulgaris (several thousands).
The first singing birds this year included: Blackcap Sylvia atricapilla, Blackbird Turdus merula, Woodlark Lullula arborea, Corn Bunting Miliaria calandra, Green Woodpecker Picus viridis and other woodland species. We also caught a glimpse of two butterflies: a Brimstone Gonepteryx rhamni and an Admiral Vanessa atalanta. Spring at last!

If you'd like to experience a vast array of widlife in Istria this spring, here is a tour we'll be co-guiding with Honeyguide Widlife Holidays. For other tours covering Istria see WildSlovenia - Tours.