Showing posts with label Insects. Show all posts
Showing posts with label Insects. Show all posts

Monday 5 October 2020

Sexton or Burying beetles in France

 

Our house is full of places where animals live and overall we are happy with that and it rarely causes any actual harm although occasionally something dies which needless to say can smell a bit.

Fortunately, as always, the natural world is well equipped to deal with any small corpses that are inaccessible, (as they invariably are), and Burying or Carrion beetles are one of the insects that make their living from such things. There are some 20 odd species in France with a total of 30 species in Europe although not all are true burying beetles; some of them eat fungi or rotting vegetation.   

This year in September we were finding Nicrophorus vespillo in one part of our house and I would speculate that they had been on a dead Loir, (Edible Dormouse), probably behind the bath or false wall in the downstairs bathroom, one of the places where they frequently live. These amazing beetles can smell a corpse from a vast distance using the highly sensitive hairs on the ends of their club ended antennae. Having found a corpse, usually that of a small mammal, both male and female set about preparing it for use, sometimes excavating below it to bury it or even moving it if it’s small enough. Hairs or feathers are removed as are any eggs or larvae of other species, (flies etc), and the body is shaped into a ball where the beetles eggs are laid around it. Both parents feed and care for the young larvae when they hatch and this can last for up to 10 days before the young can consume the corpse directly. This feeding of the young larvae by adults is very rare in the insect world and is normally associated with social or colony forming species such as honey bees, wasps and ants. In addition to this unusual behaviour the parents are known to regulate the number of larvae in relationship to the quantity of food available on the carcass by removing and killing some larvae if there is a shortage of food or laying more eggs if there is plenty, thus having larvae of different ages on the same corpse. Larvae pupate in the soil or debris under the corpse before emerging between 20 and 30 days later.

 

Nicrophorus vespillo, burying beetle with mites in France
Nicrophorus vespillo with mites

As with some other insects, notably some Bumble bee species, these Burying beetles carry with them several species of phoretic mites that use the beetle as transport from one corpse to another. The relationship between these mites and the beetles has generally been thought to be benign but there is extensive research continuing on what the actual relationships and effects are. Needless to say it’s too complicated a subject for me and to go into here but I’ve put a link below and to a great video. 

Chris

LINK Phoretic mites and beetles 

LINK  Video burying beetle at work and larvae


Tuesday 8 September 2020

Bees killing hornets in France


I know it is stating the obvious but every year is different in the natural world and no two years can be the same, however this is becoming increasingly exaggerated.

Habitat loss, agricultural methods and climate change along with other factors are causing rapid major changes for our native species requiring them to adapt or perhaps in some cases disappear completely.

For some species this is creating opportunities and they have expanding populations that are sometimes associated with an expansion in their range. However for most species there are accelerating declines and this in turn leads to changes of behaviour as species attempt to adapt.

Where I live most insect species have been in overall decline for the last 25 years and this year has been abysmal for them but I want to talk specifically about hornets. 

Following the usual slow start as nests were established and populations grew I started to see a gradual increase in both Asian and European hornets in the 2nd half of July and there are presently sizeable numbers of both around the hives and where the bees take water. Of course it’s to be expected that the Asian hornets would be behaving like this but it’s the native European hornets that are behaving differently in so much as they are concentrating their activity on taking honey bees. They always do take some but this is different and I can only speculate that it’s the shortage of all the usual insects they take to feed their larvae. This in turn is putting them more in harms way than would otherwise be the case and I have been finding several dead European hornets in front of hives.

Unlike the Asian hornets that keep their distance I have noticed that our native hornets tend to get very close to the hive entrance, even briefly landing on it, so it was no surprise that when putting the mouse guards back on the hives for winter the other day I saw a European hornet mobbed by a mass of guard bees when it got too close to the hive entrance. The hornet didn't stand a chance but it was 45 minutes before the bees were finally satisfied that they had dealt with her.







Amazingly no bees died in the process.

Chris


Saturday 25 July 2020

Chafers and Honeybees in France


The other day a chap on a French Beekeeping Face book group posted a photo of a beetle trying to get into one of his hives.   His initial reaction having “Googled” was that it may have been a Large hive beetle, Oplostomus fuligineus, a species that is found in Africa and although this has not yet been recorded in France we can’t be sure where anything is going to turn up these days. New non native species seem to arrive on almost a weekly basis in France and the Small hive beetle, Aethina tumida, another non native, has been found in Italy but as of this moment hasn’t reached France.

Anyway it was clearly a Chafer, that much was indisputable but not a Large hive beetle. I was sure, (ha,ha,ha), at first that it was dark Rose Chafer beetle due to its general appearance and size, (close to 2cm). However I couldn’t find any evidence of Rose Chafers trying to enter hives and although they are plentiful at our place, (Rose chafers and hives), I have never seen them on my hives so I started to deepen my search for any examples of this. After much searching and changing search terms I finally came up with some examples of where peoples hives had been invaded by chafers, but not Rose Chafers but Protaetia morio known as la Cétoine noire. In many ways they look like dark Rose chafers, they are 1.3 to 2 cm long, the dorsal surface is dull, blackish to brownish with small ochre spots more or less marked, or even absent, on the pronotum and aligned transversely on the elytra. Although the greatest populations are to be found in the Mediterranean zone they are present to some extent in almost all other regions of France. Other than the fact that they are attracted to honey their behaviour and life cycle is much the same as the Rose chafer, feeding on thistles, knapweeds etc with larval development in rotting wood and fibrous soil.  

Click on images to enlarge


It seems that the observations of them entering honey bee colonies take place in July and August and if the beetles are numerous they can cause severe disruption for the bees which can’t eject them as the beetles bodies and wing cases are too hard for a bee sting to penetrate. In the case of a hive it should be a simple case of using a hornet guard to keep them out but we can assume that they have developed this behaviour over thousands of years by entering natural colonies in trees.







Chris

Wednesday 20 May 2020

May bug – Cockchafers - Hanneton commune and Hanneton forestier in France.


Hardly extraordinary I can hear people thinking but the other day I saw a May bug here, first one in several years. In fact in the 25 years we have been here there have only been a couple of years when I have seen them.  

A May bug or Cockchafer generally refers to Melolontha melolontha or the Common Cockchafer but there is an almost identical species in France with which they could be confused which is the Forest cockchafer, Melolontha hippocastani, which is a species found in woodlands.  

Generally Melolontha melolontha is considered an to be  an agricultural pest and they were brought almost to the point of extinction in the arable areas of France following the use of chemical insecticides such as DDT and Lindane. Both of these caused massive environmental harm before being banned from use. In the 19th century prior to insecticides being available the beetles were collected by hand to be killed, a process called “hannetonnages” that had some effectiveness even if a little laborious. Schoolchildren would sometimes be enlisted to perform this task where they would place sheets under the hedgerows in the morning and shake them out, collecting them in containers. Back at school the chafers would be weighed and some payment made by the kilo, a kilo roughly equalling 1,200 chafers. We can only dream of such numbers these days.

Since the 1970’s their numbers have slowly recovered on pasture land. However where intensive arable farming is practiced they are few and far between as almost every available piece of land is cultivated and constantly ploughed. This practice makes it close to impossible for them to complete their life cycle as any larvae, in the unlikely event that there should be any, are constantly bought to the surface and exposed to the birds that follow the tractors. This only leaves the roadside verges and any small uncultivated parcels of land. The situation has been made worse by the removal by the EU some 15 years or so ago of the requirement for farmers to leave a percentage of land fallow. This resulted from the misconceived idea that bio fuels are more important than habitat, a decision that has caused and is causing untold harm to a vast range of species.   

Chris


Thursday 27 June 2019

France and the banning of neonicotinoid insecticides


France Becomes The First Country To Ban All Five Pesticides Linked To Bee Deaths.

Most of us will have seen this or similarly worded headlines on a myriad of mainstream media sites, blogs, alternative information sites and sites that are simply click bait for advertising revenue. Many of these so called articles are full of sensational erroneous statements and speculations that have no factual or scientific foundation what so ever.

Large numbers of people will have liked, shared and commented on these pages without any idea of what the reality is or giving it any real thought.  Most of us do this at some time or another on social media because to do otherwise would be too time consuming.

So what actually is the reality?

Yes, France has banned the use of five types of neonicotinoid insecticides that by definition have been shown to cause harm to insects.  This is two more than the EU have banned, although countries frequently derogate from the ban in certain circumstances, most recently, (Dec 2018), Belgium and some other countries are allowing sugar beet growers to use Imidacloprid as a seed treatment for 2019.  Seed treatments have been by far the main method of delivery used here in France principally on Oil Seed Rape, Maize and Sunflowers. They were also used as foliar sprays on fruit crops of most types after flowering.

However, that is not the end of the story.  Neonicotinoids are still used in flea treatments for domestic creatures and in the house plant industry.

There is little point discussing just how much, if at all, the neonicotinoids that were used in France affected honeybees, which are, after all, generally a commercially managed species here in the same way that chickens and pigs are. Overall there has been no decline in honey bee colonies.

It is however highly likely that they have contributed in no small manner to the decline of many other insect and bee species by virtue of sub lethal doses adding one more stress factor. Having said that, it’s impossible to quantify exactly what role they played against the backdrop of massive habitat loss and the large scale use of other pesticides, (some 2,500 authorised in France).

Here comes the rub. Without meaning to sound churlish, banning the five neonicotinoids in itself isn’t that big a deal when it comes to protecting the environment and saving our wildlife populations as a whole. What the ban has brought about is a return to open spraying of other pesticides, (although fungicides have always been open sprayed).  The problem is particularly bad when it comes to OSR* where the crops are sprayed when in full flower. This not only impacts all the different insects that are foraging or living there but also all the birds that nest in or along the margins of this crop.  In particular Linnet, Stone Chat, Yellow Wagtail, Corn bunting, Yellowhammer, Hen Harrier and Montague’s Harrier. Hedgehogs may also be present and foraging although not during actual spraying.

Click on image to expand



In conclusion, although this ban may be beneficial it is nowhere near enough given France is one of the greatest users of pesticides in Europe, something that is increasing at a substantial rate year on year. Huge changes have to be made if we are “to save everything” and not simply shuffle the cards using the same deck and still be killing as many species. 


OSR – Oil Seed Rape.

Pesticides – an overall generic term now used for all “cides”. Insecticides, Herbicides, Fungicides,  Rodenticides and so on.

Chris

Thursday 21 March 2019

Assassin bug the Masked hunter, Reduvius personatus, in France


Masked hunter, Reduvius personatus,  Réduve masque

Found in most regions of France this member of the True bug family is known as an Assassin bug and due to its secretive nocturnal behaviour it tends to go unnoticed even when in your home.

They are especially fond of old houses, barns and outbuildings where they hunt other insects including bedbugs, silverfish, book lice and flies. However they will eat any number of small insects and can also be found in other habitats including woodland, scrub and grasslands but always avoiding the light. Where ever they are they are never in large numbers.


Although they bite and kill their prey by piercing them with their robust rostrum they rarely use this against humans unless handled roughly but if they do it isn't dangerous but can be extremely painful.

They spend the winter as juveniles and then breed in May or June having reached the adult stage.  During their development stages, (instars), they exude a sticky substance and coat themselves in dust and debris presumably to camouflage themselves.


Rather like the House Centipede they help maintain a balance in the home by predating on other insects even though you may not even be aware of their presence. 

Chris







Monday 11 March 2019

Ladybirds in France including the Asian Harlequin Ladybird


Every year in autumn and spring there are articles in the media, especially in the UK, about the Asian Ladybird, Harmonia axyridis, or Harlequin Ladybird as it is known, one of several thousand different non native species introduced in both France and the UK although only a few are ladybirds. This species is generally regarded as the most invasive ladybird on Earth and although they undoubtedly have an environmental impact due to their high breeding and survival rate combined with their voracious appetite most experts are of the opinion that they are now so abundant that there is little if any point in killing them.


Harlequin ladybirds, above, are extremely variable but most have a clearly defined "M" or "W" on the pronotum.

Although they feed most commonly on aphids they have a wide food range that includes scale insects, adelgids, the eggs and larvae of butterflies and moths, many other small insects including other ladybirds, pollen, nectar, and sugary fluids, including honeydew and the juice from ripe fruits bringing them into direct competition with native species of Ladybird many of which are already under pressure resulting from all the usual reasons, habitat loss and pesticide use being uppermost.

The risk as always that comes from articles in the media and the consequent sharing on social media is that some people will unwittingly start killing anything that they don’t recognise as the stereotypical image of a Ladybird, generally the most common of which is the Red and Black spotted 7 spot ladybird, and there are too many people already locked into a “kill everything that isn’t a butterfly” mode of thinking.

To move on, there are 90 or more species of native Ladybird in France most of which wouldn’t be recognised as such. Some are brown, some black, some yellow and black, some black and red, some orange and perhaps not surprisingly many are highly selective about where they live and what they eat with many being vegetarian.

It would be difficult here to include that number of native species, so I have listed a few here to give some idea of just how different they are. 

Kidney-spot ladybird (Chilocorus renipustulatus) Black body with large red spot on each wing case, feeds on scale insects on the bark of trees.

Pine ladybird (Exochomus 4-pustulatus) Usually elytra are black with two larger red comma-shaped spots and two smaller red round or oval spots, feeds on aphids and scale insects.

Heather ladybird (Chilocorus 2-pustulatus) Black with 2 to 6 red spots feeds on scale insects.

16-spot ladybird (Tytthaspis 16-punctata) Beige with black spots. Feeds on Aphids, Pollen, nectar and fungi. Can overwinter in large numbers, 50 or more in one cluster.

Orange ladybird (Halyzia 16-guttata) Orange Ladybirds can be bright yellow or orange in colour with 16 creamy spots. Feeds on mildew.

22-spot ladybird (Psyllobora 22-punctata). Bright yellow with 22 black spots. Feeds on Mildews

24 spot ladybird (Subcoccinella vigintiquattuorpunctata) Sometimes known as the Alfalfa Ladybird. Orange –red, number of spots may vary. Feeds on a variety of plants including Campions, vetches, trefoils, chickweed and plantains among others. They will also take grasses and in France can be a pest of lucerne.

Hieroglyphic ladybird (Coccinella hieroglyphica) brown or black with black stripes, spots and patches. Feeds on larvae of Heather leaf beetle.

Bryony ladybird (Henosepilachna argus) Orange red with 11 black spots. Feeds on White bryony and plants of the Melon family.

28-spotted potato ladybird (Henosepilachna vigintioctopunctata) Orange with 28 spots feeds on the foliage of potatoes and other solanaceous crops.


 Chris.


Sunday 9 December 2018

Hedgerows and Dry Stone Walls in France

As soon as we start to take a look at either Hedgerows or Dry stone walls it soon becomes clear that in France as in many parts of the UK it’s difficult to talk about one without the other.

Although there have been what could loosely be called hedgerows to some extent in France since before Roman times they really started to come into their own in the 16th and 17th centuries as the available land not already owned by the nobility or the Church was eagerly snapped up by the wealthy middle classes, the bourgeoisie urbaine. They used hedgerows to define their boundaries, to protect their crops and to prevent other farmers from grazing their land. Apparently hedge laying, (plessage), was widely used throughout France but has disappeared without a trace in many regions since the 1960’s and I have yet to see an example or a remnant in our region.  From the end of the 19th century and into the first half of the 20th century the industrialisation of agriculture started to change the face of the countryside only interrupted by the two world wars that France was subjected to. Following the second world war with mechanisation the changes to the nature of our landscape and the removal of hedgerows gathered pace, something that was given greater impulse with the land consolidations of the 1970’s and 1980’s and the move towards larger and larger fields when much of our hedgerow network was lost. All in all it is estimated that France has lost an astounding 2 million km of hedges and this is certainly not without its consequences.
Click on images to expand 

Above - Hedgerows take up farmers land.
Below - The convenience of removing them.


Throughout the same timescale we see the rise and literally the fall in the use of stone walls for enclosures, (murets de pierres) or sometimes a combination of the two, a dry-stone wall with a hedge. These can be found today in many parts of the region although the walls are often dilapidated and only partly standing other than when maintained around gardens. To most landowners they are generally at best of no interest or even a hindrance to their activities. Again the losses have been massive.
Above - remains of dry stone wall and hedgerow

Hedgerows come about in different ways, for different purposes and will contain different species. Leaving garden hedges aside from a strictly practical perspective for most farmers and landowners that meant making use of the most robust and abundant natural species that were probably growing there in the first place. Most people will know what they are, especially if they have a bit of rural land. Bramble, blackthorn, hawthorn, hazel, spindle, chestnut, oak, box, field maple, elm, beech, holly, ivy, dog rose and wild privet are all typically found and can provide a dense livestock barrier when managed correctly and do a rather good job of keeping people out as well.  Correct management, in this case, is keeping the hedge height and shape compact with a height of around 1.5 to 2.5 metres and a width of 1 to 1.5 metres. This will help prevent gaps appearing, something I see too often here where even newly planted hedgerows are simply left to grow into a row of closely planted trees with huge gaps and limited usefulness, however the occasional tree here and there that is allowed to mature as part of the hedgerow can be beneficial. 

 Above - Hawthorn berries 
   Below - Rosehips on Dogrose  

As mentioned there is little practical need for hedgerows by landowners anymore, indeed in my conversations with local agriculteurs they are often proud of the wide open landscapes with no nasty hedgerows to obscure the view and make life difficult. Where required the introduction and easy availability of metal wire, stock fencing and electric fencing has done away with the requirement for hedgerows. Whilst not wishing to blame them it needs to be understood that hedgerows and dry stone walls have a usefulness and long-term economic value both to farmers and wildlife that only too often hasn’t perhaps been considered or taken into account.

Hedgerows and Dry stone walls provide unique habitat structures that are completely different to anything else including woodland. Importantly they heat up and retain heat in a completely different way that provides protection and breeding habitat for birds, reptiles and mammals as well as a vast number of insects throughout the year. Another feature which will have been noticed by anyone that walks in the winter is that they provide fantastic windbreaks giving shelter from wind and driving rain on the lee side. This same wind break action helps to prevent the soil erosion that results from modern cereal production methods; in fact soil erosion now affects most of the main cereal growing areas in France and other major agricultural production regions and can amount to several tonnes per hectare every year. Given it takes around 500 years for just 2.5cm of topsoil to be created amid unimpeded ecological changes this is a resource we must conserve.
Good dense hedgerows will also build up a mass of living debris at the base, something that takes many years to establish and is of great value to both wildlife and maintaining the soil structure, somewhere for vast numbers of ground beetles and other insects to survive that will, in turn, provide food for hedgehogs and small insect-eating birds. As well as the bushes and trees that make up the hedgerow there will be numerous native flowers that find a place at the base, far too many to name here with native climbers such as Honeysuckle and both Black and White Bryony and White Bryony  provides food for the Bryony Ladybird, Henosepilachna argus, that eats the leaves. 
 Above - Bryony Ladybird
Below - Bryony Ladybird Larva eating Bryony leaves

Everywhere we look we find that all of the plants and the shrubs that are part of this structure will all have an importance to other species with many having unique or specific requirements.  Leaves provide food for specialist caterpillars, flowers provide nectar and pollen for different species of bees and other pollinators, broken hollow bramble stems are where the Small carpenter bee, Ceratina cyanea, a very small solitary bee species you may hardly notice lay their eggs. No article about hedgerows could leave out the importance of all those berries many of which rely on being eaten to be distributed far and wide having passed through a bird or a mammal. Blackberries are perhaps the most widely eaten of all our native berries, Birds, Pine and Stone Marten, Wasps, Hornets, and various other insect and fly species all have their share, not to forget humans. Hawthorn berries and Rosehips are sought after by the Thrush family, (Fieldfare, Redwing, Song and Mistle thrush), in winter when the weather is extreme and the ground is frozen. Hedgerows are also of huge importance to certain species of bat particularly Natterer’s bats and the two Horseshoe bat species, Greater and Lesser. Last but not least we will all have seen dead Barn owls by the side of the road and may even have been unfortunate enough to have collided with one in flight, I have and it isn’t a pleasant feeling. These collisions invariably occur where hedgerows have been removed for the simple reason that Barn Owls hunt by sweeping low across the land and a simple thing like a hedgerow pushes them up and over any traffic.
Above - Injured Barn Owl - one of the lucky ones

We have reached a point where although there is still a net loss of hedgerow each year the pace of removal is slowing; arguably it will be anyway because so much has already disappeared. Also there are land owners and sometimes communes that are planting new hedgerows and in the Vienne the LPO helps raise finance to plant hedgerows every year for a dozen or so small farmers that want to improve bio-diversity on their land.


In Poitou-Charentes the Association Prom’Haies provides a wealth of information and services to assist people in planting hedgerows located at :
Maison de la Forêt et du Bois - 79190 MONTALEMBERT - Tél : 05.49.07.64.02

Whilst welcoming all new hedge planting we do need to remember that a newly planted hedge will take many, many years to be anything like as useful as a hedge that has existed for 50 years or more so saving existing hedges should be a priority with continuity maintained wherever possible to preserve their role as wildlife corridors. Perhaps it’s worth mentioning that in December at Saint-Ciers-de-Canesse and Pugnac in the Bordeaux vineyards two 190 metre hedgerows have been planted to protect the school and its playground from spray drift following the 2014 poisoning of children in the Villeneuve School that resulted from spraying the adjacent vineyard. This type of planting is set to continue in other places where children are at risk.


As for the tragic loss of dry stone walls it unlikely that much can be done to redress this and it seems certain that most of those that exist in the open countryside will continue to disappear as they have no economic value. 

Chris 

Friday 30 November 2018

Hunting in France and the decline in species


What role, if any, does hunting play in the massive species population declines we are experiencing across the board in France?



Hunting is one of those subjects that invariably divides people into being either for or against with both sides of the argument frequently suffering from the blindness and anger that comes with entrenched attitudes but the question that needs to be asked is how much harm results from hunting relative to other perhaps more acceptable activities when it comes to the declines in wildlife that we are witnessing? 

Looked at objectively it soon becomes clear that although the practice of hunting may be abhorrent to many people it doesn’t really have any impact on the populations of deer and boar, (gros gibier or large game as they are known), which is the main form of hunting in France. Many birds are specifically bred to be hunted such as Pheasant, Red-legged Partridge & Mallard and as such don’t really count, (see link at the bottom). Where we have bird populations that are already in decline resulting from other causes then clearly hunting these species must be considered as an additional factor.   Skylarks, Turtle doves, Black-tailed godwit, Curlew and Woodcock are just a few obvious examples of this.

It’s also the case that some species are persecuted relentlessly throughout the year being seen as vermin and this is not without consequences. Hunting may play a role in this where some species are concerned with Foxes, (with perhaps a million killed a year), along with Badgers topping the list. Although not strictly hunting as such the trapping and poisoning of other mammals has both a direct impact on the species concerned and also on non-target species that fall victim to the traps or poisons used.  Owls, Black and Red Kites and Hedgehogs are all well known to suffer extensively from non-target poisoning along with smaller birds that die after eating poison grain that is spread around industrial, residential and farm buildings for rodents to eat. Pine Marten, Stone Marten and Polecats are trapped and killed as well as being poisoned which is significant when taken alongside other causes of population decline.

Collisions with vehicles are a major cause of mortality for a number of species of birds, mammals, insects, reptiles and amphibians. What this amounts to is hard to gauge but some of our more threatened "common" species such as Barn Owls and Hedgehogs will be seen regularly dead on the road or by the roadsides as well as snakes and amphibians at certain times of the year. 

Given the above all of which have some degree of importance the greatest overriding cause of population decline for the majority of species is loss of habitat and the widespread use of pesticides, (fungicides, insecticides, herbicides, rodenticides, bactericides, molluscicides etc). Habitat loss covers a broad spectrum that removes or reduces sources of appropriate nutrition, sites for depositing eggs, nesting sites, adequate cover and shelter. It’s hard to find anywhere or any situation where these circumstances don’t apply with agricultural practices being by far the main cause but we need to see that habitat losses apply equally to our homes and gardens.  New or renovated buildings rarely leave places where wildlife used to thrive; eaves are sealed and walls are neat and smooth which removes millions of roosting or nesting places for birds, insects, bats and other creatures.

Where agriculture is concerned it would be hard to find any aspect of it that hasn’t had an extremely detrimental impact on our wildlife with many species being pushed to the edge. Pesticides, removal of hedgerows, the cultivation of every marginal piece of land all responding to greater and greater pressures for more animal feedstuffs and biofuels along with increased pressure to fill the supermarket shelves with a constant flow of uniform fruit and vegetables half of which is wasted. Add to this the mountains of cakes and pastry products all requiring evermore wheat production.

It’s also worth mentioning the impact that many of the introduced non-native species are having on our native species by way of predation or competition for available resources. Asian Hornets, Box moth, Louisana Crayfish and the American Bullfrog are well-known examples but there are hundreds more.

The effects of climate change are too difficult to quantify at the present but undoubtedly play a role that can only grow in the future.

So when it comes to species declines it’s quite clear that hunting doesn’t really begin to count and even from a cruelty perspective it’s no different to the rearing and slaughter of most commercial meat, fish and poultry for the mass consumer market.

For the record, my own view is that hunting and killing other species is rarely justified and that the killing of wild or native birds, in particular, has no place at all in the 21st Century.

Species it is permitted to hunt in France  

Preventing hunting on your land in France  

Industrial breeding of species for the hunt.


Chris


Monday 15 October 2018

Giant resin bee Megachile sculpturalis in France



Up to 25mm in length this huge leafcutter bee is a relatively new arrival in France that is rapidly and literally making itself at home and is nicknamed the Squatter bee for reasons that will become apparent. 

First observations of this bee in France were made in 2008 in Allauch, north of Marseille. Since this date they have spread a long way and in the space of a few years have conquered a territory that includes all the southern half of the country!  The main concentrations not surprisingly follow the Rhone valley as far as Macon in the north to the Mediterranean in the south spreading West as far as Spain and East into Italy, Switzerland and Germany becoming relatively commonplace in gardens south of Lyon.

Map source - VigieNature

It is thought to have first arrived in a shipment of timber into the port of Marseille from the USA where the species had been introduced at an earlier date, (first observed in 1994 in North Carolina). Originally the species is found throughout the eastern Palearctic and Oriental regions including Japan, China, and other parts of eastern Asia.

Although the species is known to fly great distances the main advantages that are aiding their rapid expansion are due to their nesting behaviour and diet. Although some native flowers are used for nectar and pollen collection there is a marked preference for plant species introduced from Asia for ornamental purposes. In some cities like Nîmes and Montpellier, the pollen analyzed shows a predominance of Sophora japonica ... at nearly 96%! This ornamental tree with white-cream flowers is very popular with city dwellers: it adapts well to polluted environments and grows quickly and despite the name is native to China.


For nesting it mainly uses the large holes that have been made by the Carpenter bees Xylocopa violaceaXylocopa valga but unfortunately not only when they are disused occasionally aggressively ejecting any occupant with its powerful mandibles.  A hole of around 10 mm is preferred which females prepare using resin and sap collected from trees although mud and other materials may be made use of. As with other leafcutter species, an egg is placed in a cell, provisioned with a pollen ball and sealed, a process that continues with up to 10 cells, the last which that is open to the air being sealed with a hard coat of resin. After hatching, the larvae feed on the pollen and overwinter in their cells pupating in late spring before emerging in the summer.  

They have also been found in a large number of bee hotels where larger tubes or holes are ideal for them.

It’s highly likely that this species will have a serious impact on the ecosystem in France both directly on our large carpenter bees and on the available sources of forage for other pollinators.


Chris

Wednesday 10 October 2018

A Grass carrying wasp and a Mud dauber in France

A couple of interesting introduced species in France that many people will have come across and which are noticeable due to their somewhat unusual behaviour.

Isodontia mexicana known as the grass carrying wasp and Sceliphron curvatum a “Mud dauber” have established themselves rather successfully in France. Isodontia mexicana can be found in all regions and Sceliphron curvatum is so far restricted to more or less the southern two-thirds of the country but the expansion is rapid.  Both belong to the Sphecidae which are a cosmopolitan family of wasps of the suborder Apocrita that includes sand wasps, mud daubers, and other thread-waisted wasps.

Isodontia mexicana arrived in Europe from North America in the 1960s. For several years, it remained confined to the Mediterranean region, but from 2003, a year which was particularly hot, it began to extend its range northward. It is currently found in France, Switzerland, Hungary, Italy and Spain. They are black with smoky brown wings and measure between 15 and 25mm with females being larger than males. The adults feed on nectar with plants such as mint, wild carrot and other umbellifers being especially favoured.

Females use existing holes or hollow plant stems as nest sites where she may create as few as 2 cells or as many as 8 cells depending on space available each cell being separated by plant fragments. Each cell is provisioned with a living grasshopper or cricket that has been paralysed and on which she places an egg thus providing the fresh food the larva requires for its development. Finally the hole is stuffed with dry grass or stalks, hence the common English name. Eggs that are laid late in the season will overwinter after sheltering in a cocoon they have spun (diapause) and emerge in May or June. Early broods at this time of year will produce a summer generation that develops in a few weeks giving us two generations in a calendar year. 

    Click photos to enlarge

Photos above of Isodontia mexicana & nests

If you have a “bee hotel” and live where there are plenty of grasshoppers there is a very good chance that they will use that. Only significant predators are thought to be birds.
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Sceliphron curvatum.  The native range of this species extends from Iraq to northern India and Nepal, and from Pakistan to Kyrgyzstan and eastern Uzbekistan.  The evidence points to the fact that it probably arrived in France a little before 2010 when the first confirmed identifications were made following a progression eastwards across Europe starting in Austria in the 1990’s that was not a natural occurrence. .

Adults are between 15 and 25mm. The thorax is black with 2 yellow bands and the abdomen is orange with dark reddish bands.

After mating, the female builds a nest of mud that is made up of several tubular cells, each in the region of 20mm long that are constructed progressively at the same time as being provisioned with an egg and its food supply. Each of these cells is intended for a larva. When each cell is complete, the female hunts and stores enough spiders, usually from 6 to 15 but can be as many as 40, to feed the larva until it is metamorphosed. Live prey is paralyzed, thus constituting a reserve of fresh food. Having laid the egg on one of the spiders she closes the cell with mud. She continues building the nest until it has about 25 cells.

The larvae develop during the course of a few weeks and then turn into pupae in their cell, where they spend the winter. Adults emerge from their cells in the spring.

The nests are often to be found in peoples homes attached to furniture, folds in curtains, clothing and so on. I have sometimes found them between the roof of a hive and the lid and it’s likely that they search out places that are both warm and dry.


Photos above of Sceliphron curvatum. and nests

As introduced species it’s hard to say how much impact either of them causes or could cause in the future for indigenous species.


Chris