Wednesday 21 April 2021

Slow spring... but spring, at last!

We finished the previous post with snow and we'll start this one also with snow... damn it! It's spring, but winter doesn't seem to loosen its grip, especially in the mountains. The nights and mornings are still surprisingly cold in the Karst and most of continental Slovenia. Last week we started with a raptor migration monitoring near Pivka, only a few days after the last abundant snowfalls hit the area. The 14th of April was the first sunny day after the front, so a good passage of raptors was expected. But there was around 15 cm of snow on the ground and sitting on the top of a hill for most of the day was rather chilly. Nevertheless the birds put on a good show. The first bird heard when we got out of the car was a singing Cuckoo Cuculus canorus surrounded by a completely snowy landscape! As the air warmed two Black Storks Ciconia nigra appeared one after the other, descending from the Javorniki mountains into the Pivka valley. The observation spot had a clear view over a territory of a pair of Golden Eagles Aquila chrysaetos which performed well for most of the day, usually sitting on pines or soaring above their favoured ridge. Of the local raptors there was also a Goshawk Accipiter gentilis and several Buzzards Buteo buteo & Kestrels Falco tinnunculus. Among migrants there was a good north-eastward passage of Marsh Harriers Circus aeruginosus, which numbered 12 individuals at the end of the day, as well as a single Hen Harrier Circus cyaneus seen early in the morning in the Pivka valley. A colleague counting raptors on a nearby spot also observed a couple of Pallid Harriers Circus macrourus (a rare but regular migrant) going north. Other migrant raptors included a Black Kite Milvus migrans and a Hobby Falco subbuteo. Today (April 21st) we repeated the monitoring, but the migration was rather weak and we had similar species, however we added a Griffon Vulture Gyps fulvus.

A promising spring raptor-watching session?
Mt. Nanos covered with fresh April snow.
Marsh Harriers Circus aeruginosus heading north-east.
Golden Eagle Aquila chrysaetos - the local pair nesting in front of the watchpoint.
Goshwak Accipiter gentilis
Touty joined in for some afternoon entertainment.
 
 
Last week we also checked the Black Storks Ciconia nigra in the territory where we recently found a nest (the only known nesting site in western Slovenia) - it seems breeding is going well as the female is incubating, while the male is frequently seen feeding in the meadows and soaring around the territory. Meanwhile at home, we are following the nesting of the species on some excellent live cams from Estonia (here & here) and Poland (here and here). Similarly, most Slovenian birdwatchers are now glued to their PC screens, following nesting Eagle Owls from the Karst edge. The female on the first cam is incubating one egg, while on the second cam all three eggs have hatched and the chicks are being regularly fed - do take a look, it's fun!
Black Stork Ciconia nigra
 
 
Our local Short-toed Eagles Circaetus gallicus in the Karst around Sežana are also extremely active and showy. Actually we still need to figure out how many pairs there are in our area, as we keep seeing up to 4 birds together in what usually seems like an interaction between two different pairs. The area where we see them is apparently excellent for the species and probably represents a shared hunting territory. In the photos below, a Short-toed Eagle, probably male, was observed carrying a snake in its beak for at least two hours, while soaring and chasing another individual.
Short-toed Eagle Circaetus gallicus
 
 
Mid April is also the time when we begin with farmland bird censuses in the Karst. We usually cover three transects that run through excellent areas of typical dry limestone grasslands near the villages of Rakitovec, Petrinje and Osp. The main protagonists of this habitat are Woodlark Lululla arborea, Skylark Alauda arvensis, Corn Emberiza calandra and Cirl Bunting Emberiza cirlus, Hoopoe Upupa epops, Wryneck Jynx torquilla, Linnet Linaria cannabina and Stonechat Saxicola torquatus. Among rare breeders we have already found the year's first Tawny Pipit Anthus campestris (a lot earlier than usual) and Short-toed Eagle Circaetus gallicus, while (the few remaining) Ortolan Buntings Emberiza hortulana haven't returned yet. The open areas of stony meadows with sparse bushes offer an excellent habitat also for migrant passerines like Wheatears Oenanthe oenanthe, Whinchats Saxicola rubetra and the occasional Common Redstart Phoenicurus phoenicurus. It is usually good to check carefully such "groups" of migrants as rarer surprises are possible. Last year for example we found this Black-eared Wheatear Oenanthe hispanica. This time the welcome surprise was in the form of two stunning male Rock Thrushes Monticola saxatilis: one on April 16 near Rakitovec and the other on April 19 near Osp. Although this species does breed locally along the Karst edge, our observations probably involved migrants. Rock Thrush is an otherwise scarce breeder of rocky grasslands in the mountains and hills of western Slovenia.
In the thermophilous scrub of some areas along the Karst edge it is also possible to see Subalpine Warbler Sylvia cantillans, a rare breeder in Slovenia, confined to the SW of the country. We were lucky with a nice pair showing well by the side of the road, while a large flock of Alpine Swifts Apus melba and Common Swifts Apus apus swirled overhead. Although the first Nightingales Luscinia megarhynchos arrived in the Karst already on the first days of April, they kept quiet (probably due to the cold) and only now they can be heard singing more vigorously. Spring has finally arrived... at last!

Rock Thrush Monticola saxatilis - bird 1 near Rakitovec.
Rock Thrush Monticola saxatilis - bird 2 near Osp.
Woodlark Lullula arborea
Skylark Alauda arvensis
Corn Bunting Emberiza calandra
Wheatear Oenanthe oenanthe
Whinchat Saxicola rubetra
Common Redstart Phoenicurus phoenicurus
Subalpine Warbler Sylvia cantillans
Alpine Swift Apus melba
Nightingale Luscinia megarhynchos
Hoopoe Upupa epops
Wryneck Jynx torquilla

 
On the botanical front, the main attraction of dry karstic grasslands at the moment is the beautiful and rather rare Narrow-leaved Fritillary Fritillaria orientalis (F. tenella). When roving around the meadows we usually find only a few plants here and there, although some sites can be particularly rich with them. It is actually interesting to note that we have a small population of this species in the pine-oak woodland behind our house, which clearly used to be grassland a century ago (like most of the Karst). The few remaining plants are really struggling and only a few manage to bloom every spring. Although today we can find them in woodland, they remind us (along with the occasional Narcissus poeticus, Neotinea tridentata ect.) what most of the Karst used to be in the past. 
Back in the open meadows, the first Green-winged Orchids Anacamptis morio, Poet's Narcissuses Narcissus poeticus, Trieste Gentians Gentiana verna subsp. tergestina and several others are appearing, while the omnipresent Mountain Pasqueflowers Pulsatilla montana are already saying goodbye for this year.
Narrow-leaved Fritillary Fritillaria orientalis - out in the open meadows.
Narrow-leaved Fritillary Fritillaria orientalis - in the woodland (ex pastures) behind our house.
Green-winged Orchid Anacamptis morio
Trieste Gentian Gentiana verna ssp. tergestina
Dry limestone grasslands by the Karst edge.
Active pasture in the Karst's limestone grasslands.
From limestone grasslands to the Adriatic sea.
View NW with the Karst edge on the right and the city of Trieste & Adriatic sea in the far back.


Meanwhile on the coast, Sara has been enjoying spring wildlife at Landscape Park Strunjan, among breeding Kentish Plovers Charadrius alexandrinus and farmland birds, migrants and the first blooming orchids. She actually found two nests of Kentish Plover in the salinas a few weeks ago, but during the recent rainfalls and floods, the birds seemed to have abandoned the nests. Nevertheless the record represented a new breeding (attempt) of the species after 11 years of absence at this site! Strunjan is one of only three sites (together with Sečovlje salinas and Škocjanski zatok) where the species' breeding has been recorded in Slovenia. On the migrant front she managed to photograph a stunning Hobby Falco subbuteo eating its prey on a branch above Strunjan's famous cliffs, with the Adriatic sea as a backdrop! 
Kentish Plover Charadrius alexandrinus (incubating in the 2nd pic).

Hobby Falco subbuteo with prey.
Cirl Bunting Emberiza cirlus
Serin Serinus serinus
Swallow Hirundo rustica
Lady Orchid Orchis purpurea
Early Spider Orchid Ophrys sphegodes

 

Škocjanski zatok also hosted some interesting birds recently, mostly spring migrants stopping on their way to northern Europe. A Bittern Boaturus stellaris has been present for several days, after its strange absence in winter. Glossy Ibis Plegadis falcinellus, White-winged Tern Chlidonias leucopterus and Savi's Warbler Locustella luscinioides were also the major highlights over the past few days. For the complete list of the most recent interesting observations check here.

Bittern Botaurus stellaris
Glossy Ibis Plegadis falcinellus

Last but not least, an interesting botanical find. While roving in the oak-beeck forests of the Brkini hills, Domen stumbled upon a very familiar but highly unexpected plant, the charismatic Henbane Bell Scopolia carniolica. This species, one of the emblems of Slovenian botany (named after the region of Carniola and a plant with a very rich history) is mostly distributed on the Dinaric mountain chain and along its eastern border (central and southern Slovenia). This find in the Brkini region represents a new locality for the species in Slovenia and surely the southwesternmost point of its distribution in the country. The stand containing several hundred plants, in fine bloom at the moment, grows in a small wooded and rather moist gulley, a typical site for this amazing member of the family Solanaceae. The plant is extremely poisonous (it is after all a close relative of the Deadly Nightshade Atropa belladonna) and not even pollinators are immune to its toxic properties. As the last photo shows, bumblebees can be sometimes seen having difficulty taking off after drinking nectar from this plant!

Henbane Bell Scopolia carniolica
Scopolia carniolica - in the habitat.
An intoxicated bumblebee after a drink on Scopolia.