Tuesday 27 August 2019

Late summer in the Dinaric forests

Late August marks the start of the autumn season in the forest. After the mid summer, post-breeding calm, there's a sudden increase in animal activity. Birds become again more prominent as flocks of juvenile tits, crests, warblers and finches wander around the forest. Woodpeckers become more vocal, as do owls, which start to advertise their territories again, especially in the evenings. Passerine migration is also well underway and species like Pied Flycatcher Ficedula hypoleuca and Wood Warbler Phylloscopus sibilatrix are quite numerous in the forest. Although we don't follow migration much as we once did, some days ago we observed a Collared Flycatcher Ficedula albicollis in a city park in Ljubljana. This is a locally common breeder in lowland eastern Slovenia, but a rare migrant in the west, where we live. In Škocjanski zatok we've also observed the first Bluethroats Luscinia svecica of the season - their peak migration time is the last week of August and the first week of September.
In the past ten days we visited the Cerknica area and Javorniki forests once and the forests of mount Snežnik twice. During an evening session for mammals on mount Snežnik we were lucky with a close-by sighting of a mother Brown Bear Ursus arctos and her three cubs, walking through a forest glade in the evening mist. There wasn't enough light to take any photos, so this time the scene will remain impressed in our memories instead. The same evening we also observed Wild Boar Sus scrofa, Fox Vulpes vulpes, Red Deer Cervus elaphus and heard a female Ural Owl Strix uralensis singing nearby.
Last Sunday we went walking again in the forests of Snežnik, with the main intent to see some birds. Three-toed Woodpecker Picoides tridactylus was our main target, which eluded us, despite searching hard in an excellent old conifer stand, where we usually see this rare species. Instead we were quite surprised to find an even rarer White-backed Woodpecker Dendrocopos leucotos (a female), fearlessly feeding a few meters away from us. Background sound effects were provided by Black Woodpecker Dryocopus martius and Grey-headed Woodpecker Picus canus, plus the usual mix of forest songbirds. Additional interest was provided by a nice Alpine Salamander Salamandra atra, a viviparous species of salamander, living away from water (although requiring a lot of moisture) that is rather widespread in the mountains of Slovenia. Red Squirrels Sciurus vulgaris, in both their red and black morph, seem to be very common this year.
White-backed Woodpecker Dendrocopos leucotos (female).
Large amounts of dead Silver firs Abies alba in a forest reserve on mt. Snežnik. 
Ideal habitat for Three-toed and other woodpeckers.
Alpine Salamander Salamandra atra
Long Beech Fern Phegopteris connectilis
Willow Gentian Gentiana asclepiadea
Red Squirrel Sciurus vulgaris (red morph).
Red Squirrel Sciurus vulgaris (dark morph).
Purple Cyclamen Cyclamen purpurascens
Heart-leaved Oxeye Telekia speciosa
Probable Butter Bolete Boletus appendiculatus
Apricot Jelly Guepinia helvelloides
Coral mushroom Ramaria sp.
Jersey Tiger Euplagia quadripunctaria
Common Toad Bufo bufo
Fox Vulpes vulpes
Red Deer Cervus elaphus
Brown Bear's footprints.
Forest glade on the Snežnik plateau.
Beehive in the forest with electric fence (anti-bear measures).

Saturday 24 August 2019

A new species of alien fish in the Gulf of Trieste

Lately we've been doing regular snorkeling sessions in the Gulf of Trieste and very few other field trips, so here's another, short post to notify a recent interesting find. At the very beginning of this week we observed and photographed a Sergeant Abudefduf sp. (above) in the sea near Tanki rtič/Punta Sottile, right on the border between Slovenia and Italy. This tropical fish, belonging to the family Pomacentridae (damselfish) is usually observed in shoals along coral reefs. In the Mediterranean sea it's an alien fish, already recorded in several places (Gulf of Naples, Gulf of Genoa, Malta, Israel, Lebanon). However our find is extremely interesting as it represents the first record for the Gulf of Trieste (and maybe for the entire Northern Adriatic?), The identification to species level isn't sure yet as two sister species have been reported in the Mediterranean: the Indo-Pacific Sergeant A. vaigiensis (native to the Pacific ocean, seas of Eastern Africa and the Red Sea) and the Sergeant-major A. saxatilis (native to the central Atlantic ocean). Both species are apparently very difficult to distinguish and DNA is usually needed for a final confirmation. Our record has already been submitted to local marine biologists both in Slovenia and Italy, who are officializing the record. What is sure is that no environment is free from alien and invasive species. The last photo above sums up quite well the current situation in the Gulf of Trieste, showing the newest recorded alien, the Abudefduf, together with a Sea Walnut Mnemiopsis leydi, a very abundant and invasive comb jelly in our sea in recent years.
For those of you who would like to read more about the occurrence of Abudefduf in the Mediterranean, see this article from Malta.

Thursday 15 August 2019

Snorkeling in the Adriatic

In the last weeks we've been visiting the sea and enjoying snorkeling in the Adriatic on a regular basis. We've been usually around Debeli and Tanki rtič near Ankaran, where the seabed is a mixture of rock and sand that supports a rather biodiverse marine community. Here are some of the species of fish and other marine organisms we managed to photograph with our underwater camera. We still need to improve our underwater photography, but for the moment we're quite satisfied with the results.
Mediterranean Jellyfish Cotylorhiza tuberculata - a rather common species in the Mediterranean, whose stings have little or no effect on humans. This specimen was about 10 cm in diameter.
Greater Weever Trachinus draco - regarded as the most venomous fish in the Mediterranean; typical of the sandy coast where it buries itself under the sand, becoming invisible.
Black Goby Gobius niger
Striped Red Mullet Mullus surmuletus
Sharp-snout Seabream Diplodus puntazzo
Red-black Triplefin Tripterygion tripteronotus
Sphinx Blenny Aidablennius sphynx
Dalmatian Blenny Lipophrys dalmatinus - a Mediterranean endemic, common in the Adriatic sea.
Caneva's Blenny Lipophrys canevae
Mystery Blenny Parablennius incognitus
Tompot Blenny Parablennius gattorugine
Rusty Blenny Parablennius sanguinolentus
Salema or Goldline Sarpa salpa
Mullet Mugil sp. feeding from a Noble Pen Shell Pinna nobilis
East Atlantic Peacock Wrasse Symphodus tinca
Grey Wrasse Symphodus cinereus
Mediterranean Sand Smelt Atherina hepsetus