Serious Insect Crisis

 When do we wake up?

Queen of Spain Fritillary/Storplettet Perlemorsommerfugl/ photo GB

Butterflies and other insects are rapidly declining everywhere in Europe - and not least in Denmark. Scientists point, among other things, to pesticides, monoculture and lack of space as reasons.
 
A new investigation published in the prestigious journal Science shows that the insects of Europe disappear -  this is even a talk about an ecological collapse. The German scientists have examined the insect occurrence in more than 100 nature reserves in western Europe - and the insects are extinct even in the nature reserves. The biomass of insects have fallen with more than 80 %.

The drastic decline for the insects of Europe could mean a decline in the number of birds, which has already been identified in Denmark, where since the 1970s four out of five partridges, three out of four lapwings and more than half the skylarks have disappeared. Huge areas - which earlier was nature- were ploughed without putting something else instead -  and at the same time we experience the climate changes.

Sad but true -many Danish politicians apparently do not care, on the contrary there is a support for that Denmark - as one of few countries of EU - fights against a ban on pesticides, ( because the Danish agriculture demands it), which could represent a risc both to ourselves and the wild bees.

It is said that the approval of spraying in Denmark is tough, but in the approval is alone considered if a substance is representing a risc for the ground water or if it is exceeding limits in our food. It is not  evaluated what happens upon the ground and it is not taken into account that herbicides like Roundup, which is the most used in Denmark,  simply removes all plant growth where it hits -  or that 2.500 tons various active substances are spread over 60 % of Denmarks area each year -  or that the agriculture is allowed to use almost 1.000 various products.

This means that organisms in the earth, the wild plants of the fields and the insects upon the plants and the birds who live by the insects are being pushed more and more in the intensive Danish farm land. This happens in a degree where we are the witness of a slow collapse of ecological balances in the whole open countryside. This also applies to nature reserves.

 


Source: Excerpt of article by Ella Maria Bisschop-Larsen, Præsident for Danmarks Naturfredningsforening, Journal "Natur og Miljø",  September 2017. 

Bumblebee/ photo:GB

An ecological study in Western Germany. 
The amount of insects collected by monitoring of traps in Orbroicher Bruch nature reserve in north west germany decreased by 78% in 24 years.


Each spring since 1989 insect traps have been set up in meadows and woodlands in Orbroicher Bruch nature reserve and 87 other nature areas in the West German state Nordrhein-Westfalen.

Recently the scientists presented alarming results: The average biomass of insects caught during summer was decreased from 1,6 kilo pr. trap in 1989 till only 300 gram pr. trap in 2014.

"The decline is dramatic and depressing and this applies to all kinds of insects, including butterflies, wild bees and hoverflies ", says Martin Sorg, who is entomologist from  Krefeld Entomological Society, which is responsible for the monitoring project.

Several other studies from the western part of the world support the results from Germany.

The insects disappear everywhere.






Grethe Bachmann
Source/ Natur og Miljø, September 2017 

Brown Hairstreak / Guldhale

Thecla betulae



The Brown Hairstreak has a wing span of 33-41 mm. It is easy to recognize by the golden colours of the underside and the marked black/white lines. From the upperside the female is recognizable by the large, orange spot on the front wing. The male can - seen from the upperside - look like the Satyrum-species, but these always keep their wings folded during rest.

The flying period is from first August til mid September and sometimes even later. The flying period starts later than any other Danish butterfly. Brown Hairstreak lives in pastures and light-open thickets and glades with a large growth of blackthorn or cherry plum. It overwinters as egg upon the branches of the fodderplant, and the caterpillar first develops inside the egg in spring. The caterpillar's fodderplant are blackthorn (Prunus spinosus), cherry plum (P. ceracifera) and sometimes plum (P. domestica), wild cherry (P. avium) or other Prunus-species.

The flight of this butterfly is fast and restless, but the species spend much time in the treetops, where they sit in the sun with half spread wings or seek food like honey dew. They also seek to thistle, yarrow, goldenrod, hemp-agrimony, heather or other flowers or to overripe fruit (i.e. fermenting blackberry still on the vines). Females, who need much energy by the oviposition, are seen more often on flowers and fruit than males.

Brown Hairstreak is in some years seen in large numbers, but as a rule it is few in number and difficult to find. It is in decline in the agricultural areas. It is very susceptible to pesticides and is never seen in sprayed areas. It has disappeared from some places on the Danish islands during the 1950s.

Source: Michael Stoltze, Dagsommerfugle i Danmark, 1997.


Black Hairstreak/Slåensommerfugl , Satyrum pruni,  - is a very rare butterfly, today seen in Midwest- England. It might be extinct in Denmark. Not seen since 1987.

White-letter Hairstreak/ Det hvide W/ Satyrum w-album, ccommon in most of Denmark but might be diminish because of the sick elm-trees.  

The Ilex Hairstreak /  Egesommerfugl / Satyrum ilicis, is  close to extinction  in Denmark, only known from one place.

The Purple Hairstreak/ Blåhale  (Neozephyrus quercus) common in Denmark

text and photo: grethe bachmann
photo of Brown Hairstreak, Sletterhage, Helgenæs August 2007: grethe bachmann

Grass Snake/ Snog

Natrix natrix

grass snake, photo: stig bachmann nielsen, naturplan.dk

The grass snake ( also called the ringed snake or water snake) is a Eurasian non-venomous snake - and the name natrix is probably derived from the Latin nare or natare "to swim". It is widely distributed in mainland Europe, ranging from mid Scandinavia to southern Italy. It is also found in Middle East and northwestern Africa. British grass snakes belong to the subspecies N. n. helvetica. This species is one of only three snakes to occur in Great Britain, and is distributed throughout lowland areas of England and Wales, it is almost absent from Scotland and is not found in Ireland, which has no native snakes.

The grass snake (Natrix natrix) is one of few snakes in Denmark. The Danish name is: Snog. It is usually black with a lighter underside, the two yellow neck spots are its most important characteristics, but the yellow spots might be absent in some rare cases. The grass snake is recognized from the viper by that its head is evenly into the body and that it has a circular pupil. In Denmark are found grass snakes of ab. 132 cm lenght. The female is averagely longer than the male. (average 100 cm)  The newly hatched young ones look like the adults, but some young snakes might have a zigzag stripe down the front part of the back, and thereby be mistaken for vipers. The grass snake can bite, but it is not poisonous and is usualy not aggresive towards humans.

Not being venomous, the snake's only defence is to produce a garlic-smelling fluid from the anal glands, or to feign death by becoming completely limp.The snake may also perform an aggressive display in defence, hissing and striking without actually opening the mouth. It rarely bites in defence. It may also secrete blood from the mouth and nose whilst playing dead. Its enemies are various predator species, including corvids, storks, owls and perhaps other birds of prey, and foxes.


The grass snake is protected in Denmark and many of its habitats are protected according to law. It lives in most of the country, but is rare north of Limfjorden and is not seen on some of the Isles. During the latest 100 years the grass snake has declined considerably in Denmark. In Europe the grass snake is protected by the Bern-convention. 

grass snake hunting, Sweden, photo; wikipedia.

The young grass snake eats earthworms, snails without house, insects, fish fry and tadpoles. The adult snake hunts especially frogs and toads and it swims elegantly out into the water for frogs, but is also seen hunting along the edge of a lake. When the snake is close to the prey it uses its sense of smell to catch it. The adult grass snake feeds almost exclusively on amphibians, although they occassionally eat lesser mammals and fish. A grass snake in captivity can eat earthworms, but it never feeds on carrion. Contrarily to the python the grass snake consumes the prey while it is alive and is not influenced by the poison from amphibians.

The grass snake is especially found along rivers, lakes and bogs, but also in heaths, in forest clearings, in field borders and stone dikes. It demands a varied terrain, and its preferred habitat is lakes and bogs where the sun shines - and which is surrounded by forest. If you see many frogs somewhere, you'll probably also find grass snakes. The chance to see them is especially in the afternoon where they are most active, since the water is warmest at that time.The grass snake has declined in Denmark since its prey, frogs and toads have declined in numbers and spread. Their habitats have disappeared or they are destroyed. The landscapes are more uniform and the snake needs stone dikes, field borders and alike in order to find a suitable place for laying eggs. The manure by the farms where the grass snake can lay its egss have become rare.

grass snake swimming, photo: wikipedia

Grass snakes, as with most reptiles, are at the mercy of the thermal environment and need to overwinter in areas which are not subject to freezing. Thus, they typically spend the winter underground where the temperature is relatively stable. The males appear in the end of March after hibernating in winter, and they start to sunbathe near the winter-quarter. They are ready to mate at the end of April after they have been moulting which occurs at least once during the active season. As the outer skin wears and the snake grows, the skin loosens from the body, including from the eyes, which may turn a milky white colour at this time. This presumably affects the eyesight of the snakes and they do not move or hunt during this time. The outer skin is eventually sloughed in one piece (inside-out) and normal movement activity is resumed.

bog lake Rebild Forest 2012, gb

At this point the females appear and the mating happens in the beginning of May. The females lay their eggs in mid-summer. The eggs have to be placed where it is moist and warm in a landscape like in Denmark, where the grass snake uses manures, compost piles, and piles with garden waste. Laying eggs might happen in a compost pile at least 15 cm inside the pile. The litter of the grass snake is averagely 13 eggs.The eggs are hatched in the middle of or the end of September, and  the young ones can take food at once.

If the weather is cold, the grass snake hibernates without having eaten. The young ones live very hidden and grow 10-15 cm each year. The males are mature after the third winter, the females after the fourth winter. Some grass snakes can reach an age of 23 years. In August-September the animals return to their winter quarter. If it is hot enough the snakes might mate once again. They hibernate in late September or in the beginning of October. When overwintering they demand a place which is not too moist, like a southfacing hill in the edge of a bog area, but they might also overwinter among stones in ruins, in stoneworks at old bridges, in abandoned fox graves or hollows under trees.


Folklore

fairy tale  folklore

In Danish folklore the snakes are both large and very varied. The stories about the house snake is a lesser group and those stories mostly belong to Jutland.

The country people were very familiar with its presence and they rarely hurt the grass snake, which almost belonged to the livestock like the stork did. The snake was considered as a protector of the house and a good spirit. The grass snakes liked to go into the houses and they were allowed to do so in many places, since they repaid this freedom by cleaning the house from mice and insects. And people accepted that the snake drank the cream and the milk from the milk jug and lived in and under the beds.

The beds were in "the old days" mostly alcoves with curtains or wooden doors. In the bottom of the bed were placed heather bundles as close as possible and above this was spread the bedstraw. Such a bed bottom was a popular place for the grass snake. It loved the heat, and the goodnatured animal became easily domesticated with people, who did not hurt them. The snake often resided in houses and stables.
 

There are many stories about children sharing their porridge and milk with a grass snake, and the parents thought it meant great luck for a child to eat together with a snake. An old man told about his childhood in the late 1890s: "When our parents were out working in the field,  and while we children were sitting eating, the grass snakes came and began to lap up the milk, but we thought it was exciting. "

alcove bed, wikipedia

In a village Hesselholt, Mammen parish were so many grass snakes that they walked across the floors when there was silence in the house. In many villages and parishes are told about grass snakes living in the bottom of the beds. In Kragelund, Mid-Jutland someone told that there was a big number of snakes in the manure and in the heather bundles of the beds, and the snakes milked the cows! This was a constant rumour everywhere. An old woman told about Vissing kloster. Here were so many grass snakes that they walked into the houses and resided in the alcove beds. There are lots of stories about the grass snakes living in the bedstraw and lapping the milk from the porridge.

A paper from the Danish sculptor Anne Marie Nielsen in 1918 was a story from her mother. She had told her daughter about a woman who came home and went into her kitchen, where she saw a big grass snake stand up and lap milk from a plate with milk and bread upon a children's table. People on a farm complained that there was an "ugly smell" from the numbers of grass snakes in the stable and elsewhere, but the farmer would not let anyone hurt them - and when a girl and two boys had killed a bunch of grass snakes one day, the farmer punished them with a slap in the face. He meant that the grass snake gave some sort of protection against misfortune, if they were left in peace. From many reports it is obvious that people thought they came into accident if they hurt or annoyed the grass snake.
viking house, Fyrkat, gb The sick girl and the grass snake In a village Randlev, in East Jutland, a couple of parents had a sick daughter who was also slow to speak. She often sat upon a stone near the house. One day her parents saw a big grass snake in her lap. She feeded it while she stroke it along its back and spoke to it. The priest gave her parents the advice to keep the child indoors, but she cried and was very unhappy. They let her go out again and she went to the stone with some food. The snake came back and was being fed. But the priest kept on telling the parents to keep her indoors - but then she died, and when they came out to the stone the snake lay there dead. The little boy and his snake friend.  At the island Langeland a little boy sat by the treshold, when a grass snake came up to him. He scratched the snake upon its back with a hazel twig. And the snake liked it  This happened daily for some time, but when the boy wanted the snake to eat dinner with him his father would not allow this and killed the snake. But then the boy grew insane.  The angler and the viper.  The same advice: stroking the snake on its back was also used on vipers. If someone took the viper and stroke it upon the tail with something woolen, then he could let the snake run upon his body and it would not harm him. In a magazine from 1936 someone gave this advice: "on his way to a small forest lake in Jutland to go fishing the angler met one day a reddish viper upon a tuft of grass, where it was varming itself in the sun. He began to whistle an ingratiating melody, and the snake seemed to like it. The next day he whistled for it again. He found a piece of velvet in his pocket, bound it to a stick and stroke carefully the viper along its back. The viper gave a little twitch, but when it felt the soft velvet it obviously liked to be stroked. Each day the angler he said hello to his little friend, and at last the snake was so affectionate that it stretched out its head to be stroked in the neck. The viper liked best to be stroked in the neck and it never struck out after him. He took care when he came up to the snake not to frigthen it but at last he made the stick shorter and shorter and he could now stroke it with his finger. He knew this snake for two summers but then it did not turn up anymore. It is said that this story is probably tru and many stories report that the viper is not as evil as said. I'll not advice anyone to try this viper-stroking! Folklore is folklore.

The Grass Snake King.
The stories about the king of the grass snake are similar to the stories about the Viper King, which can be read in the article about the viper here on Thyra-blog.

Silver-studded Blue/Argusblåfugl

Plebejus argus



This Blue has a wing span of 20-31 cm. Its characteristic is the strong black spots, clear orange seam band and 4-5 metallic shining eye spots. But else the various Blues are much alike. The male of the Plebejus argus has a broad black seam with a "blurred" border towards the blue. The females are easier to recognize, since they are usually brown with a golden glow, while females of Ida's Blue (Plebejus idas) are more or less blue.



Elsewhere in Europe the argus females have often blue root fields. It is often necessary to use a magnifying glass to see if the argus has a small amber coloured prickle at the tip of the front legs. The Blue species can be difficult to recognize from one another in general, and I haven't used a magnifying glass, but there were many Plebejus argus in Lille Vildmose during this week, and this is one of them. A strong wind was teasing both the Blue and me!



Plebejus argus' flying period is from mid June till late August. Its habitats are heaths and dune-heaths with worn-out vegetation or new sprouts of heather. It overwinters as an egg, which is placed separately at low plants, and the larvae's fodder-plant is low or new sprouts of heather (Calluna vulgaris) and Bell heather ( Erica tetralix), but probably also other low plants.

It is found in spread populations all over Denmark, but is declining everywhere, especially on the islands. Extinct af the island Funen in 1989, but found in isolated populations in a few places on Zealand/Møn/Falster

Source : Michael Stoltze, "Dagsommerfugle i Danmark", 1997.

Photo Lille Vildmose 26 June 2010: grethe bachmann.

The Green Frog/ Pelophylax esculentus

The frog lake in late May 2010.


Green Frog, Mid Jutland, May 2010.
photo: stig bachmann nielsen, Naturplan foto

The Green Frog/Edible Frog (Pelophylax kl. esculentus) is a name for a common European Frog, also known as the common water frog or green frog (however, this latter term is also used for the North American species Lithobates clamitans. It is used for food, particularly in France for the delicacy frog's legs. It is a large green frog with black spots and often with a light stripe along the back. It jumps out into the water with a big splash when you come near. It's about 11 cm long and found in the eastern part of Denmark and a few places in Jutland. It stays all summer by water holes close to a forest.


The frog lake lies close to the forest

The green frog has declined since its waterholes have been destroyed or reduced. It is listed and must not be gathered or killed. Eggs and tadpoles may be gathered in limited numbers and the grown frog may be gathered in limited numbers for education and research. Its waterholes are listed according to the Nature Protection Law if they are over 100m2. The green frog quickly finds new-digged waterholes, since it is moving much about.

The green frog has various sounds, both males and females croak, but only the males have "croak-bags". The grown frog takes everything which moves and which it is able to swallow. Small insects, hornets, small birds like swallows, wagtails and young birds of grebes. The green frog eats all sorts of frogs - also green frogs.

The green frog started as a cross between the shortlegged green frog and marsh frog, but has turned into an independent species via some special conditions of its heredity. The green frog lays eggs latest of all other frogs in spring and demands the warmest water. Therefore the sun has to shine on each corner of its water hole. The water has to be clean with many water plants.

It lays its eggs in the end of May in lumps of 20 up to 1000 eggs - in all about two thousand eggs. They vary much in size, which indicates that the eggs come from a green frog. The tadpoles are very shy - and this might be the reason, why the green frog can survive in water holes with fish.

When the eggs have been laid, the frogs stay at the places where they have been breeding. Some frogs walk out to larger bogs and lakes. They begin their hibernation in September, both on land and in water. Their enemies are grass snake, grey heron, otter, badger and polecat.

The green frog was earlier a common frog in many places in Denmark, but has declined much and has become rare in large parts of Funen and Zealand. This is a result of that the water holes have been filled up or been overgrown or polluted. The green frog is listed as opmærksomhedskrævende (demanding attention) on the Danish gulliste 1997 (yellow list) - and it is covered by Habitatsdirectives, Listed and Natura 2000.

Superstition: It is wellknown that to kill a frog is bad, as you are killing the soul of a little boy or girl, who died in childhood. A frog that croaks in the middle of the day means that rain is due. A frog that jumps into your home is a sign of good luck to all in the household. It is also wellknown in fairy tales that frogs have been used for love spells. And if you rub the frog over your warts then they will disappear.

Or the famous fairy tale of the Brother's Grimm about the Frog Prince. The princess has to kiss a frog which then transforms into a handsome prince.

photo May 2010 Mid Jutland: grethe bachmann

Yellow Wagtail/Gul Vipstjert

Motacilla flava



The Yellow Wagtail is a small passerine in the wagtail family Motacillidae, which also includes the pipits and longclaws.This species breeds in much of temperate Europe and Asia and has a foothold in North America in Alaska. It is resident in the milder parts of its range, such as western Europe, but northern and eastern populations migrate to Africa and southern Asia.
Yellow wagtail is like the other wagtails characterized byt its long tail, which gave the bird its name. There are various species with very varied looks, but what is shared is the male bird's yellow belly and olive back, the belly of the female birds is light yellow. The head pattern of the male is various in various species. The most common wagtail in Denmark is yellow wagtail (M.flava) with a blue-grey head with a clear white eye and beard-stripe. The male of northern yellow wagtail (M.thunbergi) which is a common migrating bird in Denmark, lacks the white eyestripe, and the head is darker than the common yellow wagtail. The male of yellow-headed yellow wagtail (M. flavissima) which is sporadicly seen in West Jutland, has an olive head with a yellow eye stripe. Neighbouring wagtails differ most, maybe because the female bird prefers the male of their own species with the clearest features - pairs of the same species have a better breeding succes than mixed pairs.
In Denmark the wagtail mostly breeds in meadows with a low grass growth, mainly along the coast and at fjorde with beach meadows. It also breeds in inland moors. The largest population in Denmark is at the birds' sanctuaries Vejlerne and Tipperne in North Jutland and at coast areas near Copenhagen and along the bay of Køge. The Danish breeding birds mainly belong to common Yellow Wagtail.
In migrations time the northern Yellow Wagtail is a common guest in Denmark. It is seen at the migration areas or resting at meadows and large grass areas, i.e. golf courses all over the country. The European wagtails overwinter in tropical Africa, while the East Asian wagtails overwinter i India and South East Asia.
The yellow wagtail's food is insects which it catches upon the ground or in the air. Lesser flocks can hunt mosquitoes in the morning- and evening hours above waters, while they in the day hours separately hunt manure flies which gets easily started from cow pats. The long tail supports the balance when the bird catches insects in the air or while running on the ground.
The yellow wagtail has declined as a breeding bird in Denmark during the last decades. This is due to that its preferred habitat, grazed moist areas have decreased either by draining, cultivating or overgrowth.
Dansk Ornitologisk Forening

Photo ⓒ Margrethekog, Vadehavet : grethe bachmann

The Elegant Red Kite


photo Bælum, North Jutland, 20. June 2009
stig bachmann nielsen, Naturplan foto


photo Skagen May 2008: grethe bachmann

The red kite is a beautiful bird of prey with its long forked tail, the long wings and the chestnut-red colour. It is about 25% larger than the buzzard. The red kite is a fantastic flyer, it often stops in mid air , then turns around and goes down to the ground to examine a possible prey. When it is marking its nest-territory it hovers like a dragon above the forest for hours, therefore its English name "kite".

The red kite has, contrary to its close relative the black kite, a limited geographical distribution. Almost the whole breeding area of the species is inside Europe. 80 % of the European population is concentrated in 3 countries, Germany, France and Spain. In all three countries the kite is declining. In Denmark the red kite breeds few in number, but it has prospered during the latest years and is now found in all parts of the country. Most pairs of the red kite breed in the eastern part of Jutland.
The red kite breeds in open landscapes with spread forests, mostly close to water streams, lakes and moors. It often takes over other large birds' nests i high trees like the nests of raven or buzzard. The nest is often decorated with paper pieces, coloured plastic, rope etc. The red kite is also few in numbers as a migrating bird in Denmark, although the number of migrating kites in East Denmark is growing in line with the growing population in southern Sweden. The Danish and south Swedish kites overwinter primarily in Spain and France. Winter-feeding in Sweden has caused that more south Swedish kites overwinter close to their breeding area, and the kite is also observed in Denmark in winter in growing numbers.

The red kite is especially known as an expert in finding and eating carrion. It has an important role as "Nature's garbage man". But it is also able to hunt and kill its prey. The young birds are fed with fresh-caught amphibians, reptiles, mice, rats, young hares, little birds, crows and seagulls. The kite takes the prey represented in large numbers at the breeding place.
About two hundred years ago the red kite was a common bird of prey in Denmark, but shooting and poisoning wiped out the population in the beginning of the 1900s. After a Danish helårsfredning (protection all year) in 1922 the species re-immigrated in the beginning of the 1970s from the growing Swedish and German populations and has since spread slowly. The south Swedish kite-population has grown from 20 pair in 1960 to more than 1.200 breeding pair at present. The red kite is still endangered in Europe caused by a direct persecution in the wintering places in Spain, but an international pressure has reduced the problem lately.


Red Kite: Observation and Photo-Gallery


Source:
DOF (Dansk Ornitologisk Forening)
Danmarks Fugle og Natur