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Tag: landscape

Reawakening at very early spring

Morning mist

Forest in the morning, tree stems covered by a foggy most, borderless steam wraps slowly rising in the air and disappearing there tracelessly.

Forests as moisture reservoir, being released in the morning due to the awakening warmth. Morning mist is nothing else than a fog, only some meters over the ground. Consisting like each fog of numerous water bodies in gas conditions, which condensate due to the cold night and seem to have springled all plants and even insects and other sleeping animals with tiny water drops.

Especially in arid environments, that morning mist watering is most wanted and essential for surviving.

With the rising sun, warmth moves the misty clouds up, where they cover the forests in a mysterious light, before the fog disappears.

Sunlight

Consisting of all rainbow colors, each color of the spectrum being defined by a specific wave length. But sunlight also consists of physical components, particles, called solar wind.
Light as essential source for life on earth, sunlight as energizer, basis for the production of oxygen. Warmer sun beams as reawakener of a sleeping forest.

Blooming

They bloom most early in the year, do not avoid to attract early insects inmidst of snow layers: snowdrops, winter aconites and crocuses.

Snowdrops (genus Galanthus) generate thermal energy due to the absorption of sunlight. This energy is essential for growth processes in cold environments.

Winter aconites (Eranthis hyemalis) have their blossoms only opened in the sunlight. Blossoms are closed over night. Opening and closing are temperature dependent growth processes. The blossoms themselves are resistant against cold. When temperatures rise to 10 – 12 degrees, first honey bee visits can be observed.

In crocuses (genus Crocus) blooming depends on the availability of moisture and warmth. Some species bloom in autumn, others in the late winter period.

All early blooming plants save nutrients as energy resources in tubers or bulbs.

Blue hour

When the sun disappears behind the horizon, an explosion of colors in red or yellowish cover the sky. In fact indicating the end of a day, in some cultures even officially a new day was dawning, when the sun disappeared, such as in Judaism, Islam or ancient Germanic peoples.

Saying „the sun is setting“ is a relict of a geocentric model of perspective. Not the sun is moving, but the observer.

When the sun is far enough underneath the horizon, the blue light spectrum dominates and creates a shiny blue sky, forming a photogenic contrast to the silhouettes of trees and landscape structures.

Moon

The only recent Trabant of our earth, presumably sirvivor of two or even several natural earth satellites in early times of our solar system.

Reflecting sunlight at night, lightening up the sky in the dark. Orientation aid for nocturnal animals, especially insects. Rhythm generator for the reproduction periods of numerous organisms.

The only extraterrestrial body that was so far ever visited by human beings. The first, which might be colonized before Mars.

All copyrights Stefan F. Wirth, Berlin March 2021

The details about snow

Misty

In former times, when people lived in a mystic world, where elves, dwarfs, leprechauns and talking wolves did their dreadful state of affairs in the midst of dark and impenetrable huge forests, people thought that even the old trees in the woods had their own thoughts.

Park Rehberge in Berlin

Uncontrollable, sounds, the snorting of the deer, a mysterious hidden, permanently changing shades in a cold and misty twilight.

Biology

A forest is only then a forest, when a high concentration of trees is given. Woods bear a great number of species, produce a majority of oxygen in our world; they are huge reservoirs of water and stabilize the ground with their tangles of roots.

Snow

Snow consists of ice crystals. Their formation within clouds depends on the presence of ice nucleating particles and temperatures lower – 12°C.

Crystals possess a hexagonal symmetry, being prism-shaped at lower temperatures and dendrite-shaped at higher temperatures.

Temperate deciduous forests hibernate without functional leaves. Most trees throw off all leaves already in autumn to be protected from desiccation in winter frost periods.

Layers of snow are excellent thermal conductors and additionally protect all life underneath from frost damages in the cold season.

Waiting for the spring time

Most life forms hibernate together with their leafless trees. Especially accumulations of deadwood contain remarkable numbers of species, such as insects, spiders, mites or nematodes. Some already begin under their snow cover to prepare themselves for the warmer season.

When all snow is gone, winter colors in red, yellow, brown and some green reappear. Early blossoming plants are already germinating.

Aerial photography

It’s a new approach to photography for a photohrapher, when using a drone. Before starting for the flight, the photographer should at least have an idea about the possible perspectives, from which his copter shall capture the photos. This requires the ability of a three dimensional imagination. Unlike in the regular photography, the drone pilot does not see the scenery with his own eyes. Only a stepwise experience allows him to guess, how a forest and meadow landscape might look in a bird perspective at a level of 50 or even 100 m.

But despite of all three dimensional imagination abilities and experiences, much photography or videography is based on spontaneous shooting reactions, based on the transmitted live picture.

Edited landscape Drone photography, Berlin 2020, copyrights Stefan F. Wirth

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If full automatic camera modi shall be avoided, manual presettings can already be made before starting the flight according to the general light conditions, finer adjustments can then follow in each specific case, when the drone is in the air.

An aerial photographer needs to resist to the danger of perceiving the environment in top-down view after some time with the drone camera only. The German laws define that a drone is only allowed to be flown in a distance of a direct visual contact. One reason is that one otherwise losses the feeling for a safe controllable space limit.

Before drones as flying cameras became commercially available for everybody, aerial photos or videos needed to be captured under more risky and also more costly conditions. Smaller planes, manned helicopters or cameras on balloons needed to take over the same function.

Being able to fly like a bird under remote control conditions is freedom for the spirit and at the same time freedom for an incredible creative flexibility.

Landscape

All aspects of our world deserve being considered as drone photography motifs (respecting laws of course) . Whether a settling, a city, a street construction, people, architecture or nature sceneries, the drone technology enables new options and aesthetic experiences. I made experiences in different photo object types (the respectation of laws has always a priority). But for my own projects I prefer landscape, weather, season and art photography.

Drone photography mostly in Northern Berlin and adjacent regions in Brandenburg, copyrights Stefan F. Wirth

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Flying in more or less remote areas with natural landscapes reduces the probability that a drone accident might harm people or architecture. But it is of course additionally important to bring no animals or plants in danger.

Landscape photos are the more interesting the more complex their composition is. But a forest with adjacent meadows is per se no guarantor for an impressive photographic piece of art.

Drone photography mostly in Northern Berlin and adjacent regions in Brandenburg, copyrights Stefan F. Wirth

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Only the contrasts of colors, shapes and different landscape elements can under optimal conditions create complexity and a fulfilling picture composition. More or less sharp edges between for example forest areas and adjacent meadows might built up an impressive and even seemingly abstract pattern, making the shot to a fascinating piece of art.

Drone photography mostly in Northern Berlin and adjacent regions in Brandenburg, copyrights Stefan F. Wirth

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Season

City structures, such as architecture, streets or walkways, seem not to underlay bigger seasonal changes (in times withoug snow or rain) . Is that true? It of course is not, the seasonal different light conditions always cause different photographic or videovraphic looks of the same location. The lack of intense green or colorful vegetation spots in between creates additionally sceneries with very different moods.

Of course the effect of different seasons is especially distinct in the nature photography. Even in case that black and white photos would be preferred, leafless trees of a winter forest usually look remarkably more interesting than an amorphic mass of grey leaves. In the colored drone photography, nobody would doubt that the diversity of autumn colors allows a much more impressive composition of structures, shapes and lights.

But also in summer or spring, when only slightly differing green nuances dominate the sceneries, eye catching drone photography can be performed.

Drone photography mostly in Northern Berlin and adjacent regions in Brandenburg, copyrights Stefan F. Wirth

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In case the greenish landscape sculpture itself does not allow a photographic highlight, then a dynamic sky can prevent the whole photo from getting lost in a boring piece of sadness.

One needs to keep in mind that a positioning of the drone camera with being for a longer time straightly directed into the sun might harm the camera sensor. Against the light photography can look stirring, but it’s often of advantage to avoid the sun body itself completely. Against the light photos usually lead to dark landscape elements in the foreground, almost consisting of silhouettes only. To receive more details on the photo it is recommended to record a higher amount of information. Raw files can be the best choice in this context, as they allow to develop details during editing, which were not visible before.

Drone photography mostly in Northern Berlin and adjacent regions in Brandenburg, copyrights Stefan F. Wirth

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Editing

To become able for an improving editing of a photo, a minimum resolution of details should be available. A resolution of 20 megapixles or more offers enough buffer for art filters or manual changes of light, color, contrast etc. The Mavic 2 Zoom for example unlike its sibling brother Mavic 2 pro with a high quality 20 megapixles camera, offers different panorama modes. One of them is created as composition of several 12 megapixle photos, which the camera automatically puts together to a 45 megapixle piece. In case drone cameras allow a raw mode and additionally a high resolution, both of these options should be chosen.

Drone photography mostly in Northern Berlin and adjacent regions in Brandenburg, copyrights Stefan F. Wirth

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Editing can have different functions combined with different intentions of the photographer. An almost perfect photo sometimes needs being only slightly digitally improved. Alternatively the entire photo might need to be stronger modified for aestethic and creative reasons to create the planned piece of art. The creativity of the photographer and editor at this has no limits, but it should be tried to avoid the ‚killing‘ of too much picture information.

Not every editing tool has a modern high quality level. Lightroom, Photoshop, pixlr and similar software of other developers must be recommended.

Drone pilot and service offering

I have more than three years of experience in the fields of drone photography and drone videography. I herewith offer my videographic dronepilot service for documentary projects, smaller movie projects, such as film – students- projects, image movie purposes or the videographic documentation of important private events, such as marriages.

I additionally offer my drone photography abilities for all kinds of fields and purposes. Preferably in and around Berlin. Please contact me via Instagram or Facebook ‚Stefan F. Wirth‘. I fly a Mavic 2 Zoom. Flying license (Kenntnisnachweis) and insurance for commercial Drone flights existant.

Ich biete mich als freiberuflicher Dienstleister der Drohnen- Videographie und Drohnen-Fotografie in allen Bereichen wie Dokumentarfilmproduktionen, kleineren Spielfilmproduktionen, zum Beispiel Studenten-Filmprjekten, Image-Filmen und Ähnlichem an. Kontaktaufnahme bitte via Facebook oder Instagram unter ‚Stefan F. Wirth‘. Ich fliege eine Mavic 2 Zoom. Kenntnisnachweis und Haftpflichtversicherung zur kommerziellen Nutzung vorhanden.

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Some photo examples in higher resolution. Copyrights Stefan F. Wirth

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Berlin January 2020, copyrights Stefan F. Wirth

Ancient villa of Pollius Felix in Sorrento/ Italy: a nature refuge

Ancient ruins around the Gulf of Naples

 

The area of the Gulf of Naples (Italy) is full of ancient Roman ruins. Besides famous excavation sites such as Pompeii or Herculaneum, also not so famous, but nevertheless very fascinating buildings from around the first century are preserved. An example is the (originally) huge villa of Pollius Felix nearby Sorrento.

 

Pollius Felix and his eccentric extended villa in Sorrento

 

Pollius Felix was a rich man and build several villas around the Gulf of Naples. But the one nearby Sorrento surely was his biggest and most eccentric domicil. He intended to unite the four elements water (sea), air, earth (rocks) and fire (artificial heating system? lava rocks?) in his architecture. Unfortunately only a part of the very extended villa is preserved. But impressively shows, how the Mediterranean Sea was made to a part of a private building. What the natives call „I Bagni della Regina Giovanna“ is a sea water bassin (may be of natural origin) that was connected via stairs and bridges with the ancient super house. A reconstruction of the whole villa by the way can be seen in the second floor of the Georges Vallet Archeological museum.

 

 

 

How to visit the ruins?

 

The ruins are accessible for free, but visitors need to have good walking and climbing conditions. First an about 20 minuts walk downwards to the sea through an old tight walkway is required. To access the major parts of the ruins themselves small pathways through mediterranean seaside vegetation is necessary. The sea water bassin can be reached via stairs. In summer, it is a popular place for (mostly native) swimmers.

 

Landscape and biodiversity

 

The whole area is covered with natural wild vegetation, private and non private gardens and olive groves. A remarkable biodiversity is present, and – depending from the season – alwas shows different faces. In spring, early summer and autumn, everything is greening and blooming, while in the hot summer season drought predominates. The area is a home for interesting Opiliones (harvestmen), Diplopodes, rose chafers, snails or lizards (Podarcis) and snakes (rarely). I visited „Villa Pollio Felice“ (also named Villa Limona) this time in spring/ early summer: April 2019. Unlike in autumn, when I mostl visited the Gulf of Naples in the past, different flowers covered the region. The most abundant species was Allium triquetrum, decorating lush meadows with their almost bell-shaped white blossoms.

 

Villa Pollio Felice/ Berlin April/June 2019 Copyrights Stefan F. Wirth

Months passing, but where has all the life gone?

I am standing in Berlin. The sky is a grey monotony. And while tiny waves gently wash around the little sandy beaches, tree skeletons surround the hidden bays on the Havel river. A semi-lucid vapor is covering the branchage of leafless treetops, already early in the afternoon. It is December in Berlin. The entire spectrum of bright summer colors is overlaid by muddy shades. Only larger groups of pine trees gleam in a greenish-black out of a giant cemetery of seemingly inanimate bodies of beeches, oaks, birches and maples. The cry of a heron in a far distance, but where has all the colorful and manifold life gone?

T. S. Eliot (1888-1965) wrote („Journey of the Magi“):

„A cold coming we had of it, just the worst time of the year  For a journey, and such a long journey: the ways deep and the weather sharp, The very dead of winter…“

Shakespeare (1564-1616) on Sonnet  97:

„…What freezings have I felt, what dark days seen! What old December’s bareness everywhere!…“

Seeming emptyness of a Forest-waterside landscape in winter, copyrights Stefan F. Wirth, Berlin December 2018. Please like my video also on Youtube, in case you really like it.

 

Bareness, emptyness, death, attributes being combined with winter since mankind exists. From the evolutionary point of view a serious problem that early humans  had to master. The seemingly emptyness was for them a very real lack of sources. They needed to prepare the winter time, food needed to be stored and protecting clothes to be stiched. There was no well organized international trade of goods, no fresh apples and pears in winter, no cheap winter jackets made in China. Winter meant to fear for the basic survival.

Today we live a different life, being independent from the seasons. Life today means for us to fear for the basic survival of our environment. What are the effects of a global climatic change? What the effects of our environmental pollution? What changes are independent from all that and just represent natural processess as they happened again and again since about 470 millions of years, when the first plants appeared on shore?

 

Most life does not disappear in winter, it just hibernates – alive!

 

The Berlin nature refuges around the forest Grunewald-terrain are interesting due to their complex mosaics of different habitats close to each other. Forest Grunewald in Berlin and the sandy beaches and bays along the Havel river offer space for lizards, an interstitial insect fauna, dry grassland visitors such as butterflies, wetland animals like frogs and newts, aquatic inhabitants like river lampreys, numerous bird species and inhabitants of wood in all kinds of decomposition stages such as bark beetles, longhorn beetles or hermit beetles.

 

Migration

 

Some animal inhabitants of the Grunewald/ Havel-area in summer migrate during the winter season, but most species stay. They hibernate and are even now in December still there.

 

Birds

 

Many birds show a strict migration behavior to avoid northern winters, others migrate in greater numbers, while some specimens stay, and some migrate only over smaller distances. Which of those migration behaviors is exactly performed by which bird species might depend on climatic conditions and is object of scientific research. NABU for example regularly starts projects, to which the general public can contribute with own observations. One of them takes place in early January and is named „Stunde der Wintervögel“ („the moment of winter birds“).

Common cranes Grus grus and greylag geese Anser anser normally migrate over bigger distances and numerous bigger routes towards southern winter refuges. Especially cranes are in summer for examples inhabitants of the Havelland Luch, thus prefer areas more western of Berlin. A trend was observed by ornithologists that more and more often, obviously corresponding with a global warming, troops of crane specimens stay instead of migrating southward.

Migration behavior of common cranes and greylag geese in Linum, autumn 2018, copyrights Stefan F. Wirth

Female of the red-backed shrike in Berlin (Köppchensee). The bird is a typical long-distance migrating animal. Copyrights Stefan F. Wirth, 2018

 

Butterflies

 

The red admiral butterfly Vanessa atalanta is known as a migrating insect. The „normal“ case is that migration from Southern Europe towards Central Europe is performed in spring. There, a summer generation develops and in autumn either tries to migrate back southward or to hibernate as adult butterfly, where it hatched, for example in Germany. But specimens mostly do not survive their tries to hibernate during our cold winters. This makes the admiral to a rare example of our summer-fauna, which over here partly indeed dies out before winter begins. The migration routes of populations throughout Europe is still topic of research. The migration behaviors seem to change corresponding to a global warming.

Admiral butterfly in Berlin, copyrights Stefan F. Wirth, 2018

 

River lamprey

 

Also the river lamprey Lampetra fluviatilis obligatory needs migrations over bigger distances. But these migrations do not correspond primarily with our cold seasons, but instead with the complexity of its life cycle. Larvae, which differ morphologically from adults, hatch in our freshwaters and develop as filter feeders within about three years, in which they  hibernate inside their aquatic freshwater habitats. They then migrate after a morphological metamorphosis towards the Sea. There they live as ectoparasites on fishes until they reach sexual maturity and then return into freshwater-rivers to reproduce and finally die. It is still subject of research, whether they return for their reproduction to the areas of their original larval development.

 

Hibernation

 

Sand lizard

 

The sand lizard Lacerta agilis  hibernates in hideaways, which are able to hold a temperature around 5°C. There they fall into winter numbness due to their unability to regulate their body temperature independently from the environment. Juveniles and adult genders start their hibernations  at different times.

Sand lizard juvenile, found in Berlin Grunewald/ Teufelsberg, copyrights Stefan F. Wirth

 

Frogs

 

Toads and frogs hibernate after finishing their metamorphosis, juvenile and mature specimens spent a diapause as a total numbness such as in lizards. Amphibians and lizards are poikilotherm, thus their body temperature corresponds to their environment (some monitor lizards Varanus were found to have physiological abilities for a limited self regulation of their temperature, which is an exception within the taxon big Squamata).

Marsh frog Pelophylax ridibundus, pool frog Pelophylax lessonae and edible frog Pelophylax kl. esculentus survive the cold season in hideaways, which maintain acceptable environmental temperatures. While pool and edible frog hibernate on land, the marsh frog spends its diapause in aquatic habitats. Skin respiration then plays an even more imortant role, which is why these frogs require a high availability of oxygene. The edible frog is even from the evolutionary point of interest, as it represents a hybride between two closely related species, namely marsh and pool frog. It is in many of its populations non reproductive with other hybrides and needs one of the parental species to reproduce. But interestingly triploid specimens of the edible frog sometimes develop in populations and bear the complete genomic information of one of the parental species. These edible frogs can reproduce with other hybrides They can be found throughout Berlin. Such specimens are difficult to be determined morphologically, as they resemble in their outer appearance either to the marsh or the pool frog.

 

Sand wasps

 

Insects hibernate in different developmental instars, if holometabolic, egg, larva, pupa and adults are options, if hemimetabilic eggs, nymphs or adults perform the winter diapause. Some insects can even hibernate in all of their developmental instars.

The quite common red-banded sand wasp Ammophila sabulosa for example is part of the insect interstitial fauna and does not practise brood care, but maternal care. Females built up several single nests up to 20 centimeters into the soil, each of them containing only one cell for the deposition of always one egg. As food supply they hunt caterpillars preferrably of Noctuidae, stun them with a sting and carry them to their nests, which will be closed with soil particles afterwards. The last brood hibernates as pupa or larva inside the nest.

Sand wasp Ammophila sabulosa in Berlin, copyrights Stefan F. Wirth, 2018

 

 

Grasshoppers

 

The grasshopper Sphingonotus caerulans is a thermophilic species, which is a typical inhabitant of sandy areas in Southern Europe. It also appears in Berlin. Its eggs are deposited into deeper soil layers and hibernate there.

Grasshopper Sphingonotus caerulans, male, found in Berlin (Köppchensee). Copyrights Stefan F. Wirth, 2018

 

terrestrial Isopods

 

The common woodlouse Oniscus asellus for example hibernates as nymph or mature adult in hideaways inside deeper soil layers, dead wood or compost. These terrestrial curustaceans become inactive, when colder temperatures appear. Specimens can live over several years (usually about two years).

An example for a woodlouse, in this case a mediterranean species of genus Porcellio, copyrights Stefan F. Wirth, 2018

 

Hibernating animal communities

 

Communities of different animal species often hibernate altogether. I focus here on inhabitants of micro habitats. Especially long living insect nests can bear greater numbers of cohabitants. But also deadwood or compost bear many different animal species side by side.

 

Ant nests

 

Nests of the red wood ant Formica rufa represent complex animal communities, as it is typical for ant nests generally. Besides ants and their brood noumerous nematode and mite species inhabit nest mounts of F. rufa. Additionally different larvae of other insect taxa can be members of the ant community, I even discovered the larvae of the green rose chafer sometimes inside red wood ant nests in the area of the Berlin forest Grunewald. Also several species of pseudoscorpions are known to science to be adapted for a survival in nests of F. rufa in Europe: commonly found are for example the species Allochernes wideri and Pselaphochernes scorpioides. Pseudoscorpion species of genus Allochernes are known to practice a dispersal strategy named phoresy. They use bigger and better motile insects as carriers and that way are transferred to new habitats. Besides ants, their suitable phoretic carriers seem to be dipterans. Also different mite and nematode taxa inside nests of the wood ant perform phoresy. A mite example is the species Histiostoma myrmicarum (Acariformes, Histiostomatidae), which seems to be carried by ants and eventually additionally also by other arthropodes.

The larva of the green rose chafer inside a nest of Formica rufa, copyrights Stefan F. Wirth, 2011

Mite Histiostoma myrmicarum (Astigmata) collected from its hibernation habitat in the soil underneath an old oak in Berlin forest Grunewald, copyrights Stefan F. Wirth, 2018

 

Formica rufa itself hibernates inside its nest in absence of eggs, larvae or pupae. Only the queen and workers remain during the cold season. Not much is known about other nest inhabitants. More research is needed.

Typical ant cohabitants (with Formica rufa) do not necessarily need to hibernate inside their ant nests. I collected deutonymphs of the mite Histiostoma myrmicarum in winter 2017/18 from soil (some centimeters deep) underneath an old oak in the absence of ants and their nest. The well scleotized deutonymph (phoretic dispersal juvenile stage) might represent the hibernation stage.

The advantage for organisms, living in ant nests, is a higher and constant temperature due to the ant worker’s nest-care-activities. Additionally the defensive behaviors of ants offer protection for those organisms being adapted (based on evolution) to survive inside ant nests.

Due to suitable temperatures, many organisms inside nests of the red wood ant might stay even active in winter. Interactions between ant nest-cohabitants can be very complex. An example is the Alcon large blue butterfly Phengaris alcon, being adapted to other ant species: Myrmica rudinodis and M. rubra. The caterpillar resembles an ant worker due to the morphology of its cuticle and the production of ant-similar pheromones. Ant workers fail for this imitation, carry the caterpillar into their nests and feed it. The butterfly’s larva hibernates inside the ant nest as larva, molts into pupa in the subsequent spring season and finally leaves the nest as adult butterfly. Still inside the ant nest, the caterpillar can become a victim of the parasitic wasp Ichneumon eumerus. Its female invades the ant nest, only after recognizing that caterpillars of the blue butterfly are indeed inside. It then confuses the antworkers due to the release of different chemicals and then attaches its eggs to the caterpillar. The wasp’s larva hibernates there and molts into its pupa inside the host’s pupa. The adult wasp afterwards leaves the ant nest.

Phoretic mites of the taxon Astigmata inside a nest of Myrmica rudinodis, found on island Usedom, copyrights Stefan F. Wirth

 

Bark beetle galleries

 

Numerous mite and nematode species live inside the galleries of bark beetles. Such a complex fauna is known for many bark beetle species. Additionally the larvae of different other insects can be cohabitants. Depending on the species, they can perform all kinds of life-strategies: being predators of adult bark beetles or their offspring or of other gallery cohabitants, they can also be microorganism feeders and prefer the bark beetle galleries due to its ideal warmth-isolation or due to the specific micro-climate that is created there by the activities of all different inhabitant activities. Besides animals, also fungi and bacteria contribute to that climate.

Bark beetle Hylurgops ligniperda and phoretic mites, copyrights Stefan F. Wirth, 2016

Wood associated nematode Diplogaster sp. found in the tree fungus Laetiporus sulphureus in Berlin, copyrights Stefan F. Wirth, 2016

Mite deutonymphs of the Histiostomatidae mites inside the galleries of the bark beetle Tomicus destruens in Italy, Vesuvio National Forest, copyrights Stefan F. Wirth, 2016

Bark beetle Ips typographus with some of its gallery-cohabitants, such as phoretic mites, found in SW-Germany (Saarland), copyrights Stefan F. Wirth, 2015

 

Furthermore the composition of species in a bark beetle gallery changes with an increasing age of a gallery. Secondary infections are often performed by other wood parasiting beetles, after the bark beetle brood finished its development and left the gallery. A secondary parasitism can for example be performed by longhorned beetles.

The bark beetle Dendroctonus micans for example infests several conifer species: Picea, Abies, Larix and Pinus. This bark beetle can hibernate in all its instars: eggs, larvae or adults. Adults can in spring sometimes be found in specific hibernation-chambers. In a research project with russian collegues, I isolated beetles of that species in the early spring season in Siberia (Russia) out of such a chamber on Pinus silvestris. Adjacent to attached substrate particles, I found nymphal stages of the phoretic mite Bonomoia opuniae, a species of the Histiostomatidae (Astigmata), which was even new to science at that time. I described this species, which I so far only know from those siberian samples. It is still unknown, whether it also appears in Central Europe.

The nymphal stages (protonymphs and tritonymphs) of that mite species might represent the hibernating instars. They were not fallen into a numbness after the collection and even remained active in a refrigerator, where my samples were stored subsequently for a while. I doubt that the mite in winter can pass through different generations as it would happen in a warmer climate, because the found mite nymphs appeared -also active- still rather weak in their cold environment. Thus I assume these nymphs to hibernate throughout the winter season. But there is still much research missing about the ecology/biology of bark inhabiting mites.

Adult beetles of Dendroctonus micans with deutonymphs of Bonomoia sibirica, Tyumen/ Siberia, copyrights Stefan F. Wirth, 2017

 

 

Berlin, December 2018. Copyrights Stefan F. Wirth

 

 

 

 

 

The mite Histiostoma blomquisti and creationism in Louisiana/ USA

New Orleans is a dynamic and a very lively city, a city full of freedom and tolerance, a city of life style and of a unique cuisine. A mix-up of ethic groups and cultures, New Orleans, the modern city, a world metropolis.

But this is not Louisiana, it is an island, an exception, New Orleans is not even the capital of this Southern Federal State. The rest of Louisiana is landscape, swamps, wetlands, pine woods, red sand, even a Red River, harmless snakes and a touch of music, not any kind of music, Louisiana is the birthplace of Jazz.

LA is unfortunately also home land of a strict two class society, with the white race in a top position and the native Americans and the blacks on a level much further below. The latter inhabit usually the so called „no go-areas“. That’s where poverty lives, where a permanent existential emergency dominates the daily routine, and yes, where based on all this distress also criminality finds a new home again and again.

It’s a land, where racism is still alive, where colored people take over the minor jobs, while the whites reign over in high positions. A land of injustice, of inconsistency, a land of religious fanaticism.

Nevertheless, beauty can be found everywhere. When the setting sun illuminates the colorful water of the Red river or shines on lying around rusty metal scrap, then a  spectacle of glowing colors blinds the eyes of the audience. When I walked across the fields and forests, then I found an inspiring silence, a flood of harmonic nature impressions, giant millipedes of Polydesmida hiding under freely lying stone chunks, butterflies colonizing rotting fruits and fluttering with a gentle noise in the air, colorful water turtles taking their sun baths around ponds, and under suitable weather conditions I witnessed wedding celebrations of a very special kind: winged ants rose in the air to mate for their first and only time.

The most common ant species is the Red Imported fire Ant, Solenopsis invicta, a fascinating social insect, but far away from being native to Louisiana. It is a so called invasive species, which was transferred to the Southern US via ballast substrate of ships coming from Southern America. The high frequency of ant colonies in Louisiana makes that species to a worthwhile research object, and even especially being an unwelcome invader, which needs to be better understood to successfully be fought.

As most known ant species, also S. invicta is characterized by hosting a remarkable number of non-ant-inhabitants in their nests, for example mites. One mite species attracted a special attention due to its habit to appear in great numbers on winged ant females and rarely also on their males. Nobody was competent to describe it taxonomically, but I was, that’s why I travelled in 2009 to the Southern Research Station of the USDA Forest Service in Pineville, funded by the German DFG (German Research Foundation). I was very friendly and courteously hosted by the 80 years old colleague John C. Moser, who supported my research by providing access to a microscope and preparation equipment. Although he did not participate directly in my taxonomic work, I honored his contributions of ideas and his interest in my work by offering him a co-authorship.

After the species description was already almost finished and the discussion was about the species‘ name, he unexpectedly insisted in the epitheton „blomquisti“, to honor his assistant Stacy Blomquist. Although he surely was depending on her young dynamic power, I was certainly not amused about this choice. Mrs. Blomquist appeared me being too much involved into the kind of spiritual devoutness, which seemed me to be typical for the whole land. But there was no way out, the species was finally named Histiostoma blomquisti Wirth & Moser, 2010. As a consequence, my name would be forever  connected with hers, an immutable fact. But I still have the freedom to emphasize that I until today think that a biological assistant without a high and internationally well known scientific reputation never deserves a species being named after her. I additionally insist in the fact that I unsolicited would never honor somebody I consider a religious activist with my scientific work. Thus I announce herwith my strict distance to Mrs. Blomquist, who accidentally became namesake of my species.

As all Southern US-States, Louisiana is a land dominated by the creationism, being part of the so called bible belt. I was told that the separation between blacks and whites even goes thus far that there exist black and white churches, but I experienced for sure that Chinese inhabitants are priviledged to be considered white, thus visiting the white churches.

Once I was invited to a private video evening. It was organized by a Chinese assistant of the research institute and a white colleague of him, a hobby marathon runner. They presented the 2003 US/ German/ British co-production „Luther“ with Joseph Fiennes in the main role. Directed by the British Eric Till, this very average movie with a Martin Luther, attractive, slim, completely unlike the historical original, fat with a strong penchant for alcohol, was a strange choice for me as a cineaste, but I expected an entertaining popcorn evening with discussions about good and bad movies. But what I then witnessed was very unexpected.

It was so silent that I could hear the air breath, the flies buzzing around, a mysterious expectation filled the room, while my two hosts stared to the screen, awaiting the first appearance of „Martin Luther“ with religious reverence and deistic adoration. I landed in a private divine service, and when Joseph Fiennes appeared for the first time, both raised their arms ecstatically into the air, praising Luther as the great only one. It kept going on like this, no popcorn for me, but very frequent cigarette breaks instead, I fled outside as often as I could.

It is a well known phenomenon that in areas of unjustice worldwide natives tend to protect their own conscience with an unfounded belief to stand under a special supervision by a god. Only a god of immorality and misanthropy claimes to have created the planet and all life on it within six days, only such a god supports the inequality of races and the discrimination of minorities.

Berlin, November 2017

Histiostoma blomquisti on fire ant queens

Copyrights Stefan F. Wirth