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

Wednesday, 3 October 2018

House Centipede - la Scutigére, (Scutigera coleoptrata) in France



Older French stone built houses invariably play host to a number of species and that includes these fascinating little guests although not all people are thrilled by their presence or their speed when they get a move on reaching speeds of up to 0.4 meters per second.

Although in everyday usage they are called a centipede or “hundred feet” they actually only have 15 pairs of legs when fully grown giving them 30 legs. The last 2 legs are particularly long, longer in fact than their antennae reaching twice the length of the body and can be nearly 6 cm. They use these long legs to form a kind of lasso which is one of the methods they use to capture prey.

Note that the common terms centipede and millipede are never meant to be factual and both are grouped together as myriapods or very many-footed.


Eggs are laid in spring and the larvae when they hatch look like miniature versions of the adult but with only 4 pairs of legs. They gain a new pair with the first moult and two pairs with each of their five subsequent moults. Adults with 15 pairs of legs retain that number through three more moulting stages (sequence 4-5-7-9-11-13-15-15-15-15 pairs).  They have a lifespan that is from 3 to 8 years with sexual maturity reached in the third year.

Mating can be tricky with the male and female circling around each other making contact with their antennae with this being the only contact they will make. The male then deposits his sperm on the ground which the female collects and uses to fertilise herself.

Prey is killed or disabled using venom that is delivered using Forcipules which are a unique feature found only in centipedes and in no other arthropods. These are modifications of the first pair of legs that form a pincer-like appendage always found just behind the head.
Venom glands run through a tube almost to the tip of each forcipule. It’s highly unlikely that these would be used on a human being unless it was trapped with no available escape such as being held in a closed hand or caught in clothing. Prey can be almost any insect including wasps and hornets and as such they can be a useful creature to have around the home as they quietly go about their nocturnal searches for food.

Chris


Friday, 28 September 2018

Wax moth and Honeybees in France

Wax moths of both species Achroia grisella and Galleria mellonella which are commonly known as Lesser Wax Moth and Greater Wax Moth have one brood per year but this leads to successive generations as they complete their life cycle and the offspring breed. The adult moths live for about a week and are mainly nocturnal.
.
In both cases the development time between egg and adult hatching is temperature dependent and can vary considerably but can be as little as 45 days with an average daytime temperature of 28 – 30°C  but can take up to 7 or 8 months. Essentially higher temperatures speed up the development. Eggs always hatch in less than 2 weeks and it can be as little as 2 or 3 days.  The larval, (or grub), stage has the most flexible lifespan and generally the longest, anything from about 4 weeks to 6 months and of course as any beekeeper knows beeswax is their food. 

Click images to enlarge


Photo Wax Moth

Both species overwinter in the larval stage. This is usually from August or September to May when pupation takes place. Lesser Wax Moth is the earlier of the two to be on the wing from late May to September with Greater Wax Moth on the wing from July to October.

Photo Wax Moth Larva about to pupate

Photo of Wax Moth Pupae on hive frames

At no stage in their life cycle can they tolerate temperatures in excess of 45°C or below 0°C. This is important to know for beekeepers as it provides 2 methods to be certain that frames are clear of them. The frames can be frozen if they have comb in them and they can be gone over with a heat gun if they have no comb in them as can the interior of the hive. 

So we can see that there is really not a huge difference in their basic biology and life cycle. 

Now we come to the frequently misunderstood question of honeybees and wax moth.


Anyone that knows anything about honeybees will know that they are fastidiously hygienic in the management of their colony and the space it occupies including sealing all un-required spaces, holes and fissures with Propolis as well as coating the entire enclosed interior with a thin coat of it. Any damaged or unhealthy bee larvae and bees are continuously removed from the colony.  What this means is that there is absolutely no chance of wax moth establishing themselves in a healthy colony. Should a female moth sneak her way in and lay a few eggs they will be quickly dealt with. Any eggs that escape the cleaners and manage to hatch will be dragged out of the colony and dumped outside or if they are wedged in a small space they will be coated in Propolis.

Only when a colony has failed and died or is at the point of dying can wax moth move in and their larvae consume the old wax. This will not prevent a new swarm from occupying the hive or empty space; they will happily move in and within a day or two will have ripped out the entire damaged comb with any pupae and larvae that are present.


Photo contents of a Wax Moth infested hive ripped out of a hive by a swarm within 48 hours


Another possible point of entry for wax moth is following the extraction of honey from the honey supers, (the boxes that are placed on top of the main hive to collect honey). Careful extraction should result in very little damage to the comb allowing the same comb frames to be used again which requires that these be stored and kept in good condition over winter. Different beekeepers have their own methods of dealing with the extracted frames, some putting them back for a short while either over or under the actual hive for the bees to remove all the residual honey. I’m not a fan of this as it creates extra work with no obvious merit and as such I prefer to store my extracted frames “wet”, that is to say with the residual honey left in place on the frames. When these go back on the hives the following spring it encourages the bees to clean and restore any damaged comb.


The important thing is to store them free of wax moth by keeping the supers with the comb frames in them sealed immediately after extraction. This is not complicated, requires very little other than a little preparation. Bearing in mind that “wet” frames will drip a little I use a plain metal hive lid to put underneath and either another or a piece of flat plywood to put on top of each stack of supers making sure there are no gaps. Whether the supers and frames are stored “wet or dry” the same principle applies of making sure they are stacked and sealed immediately and not left lying around open to the air. 

Chris  


Tuesday, 18 September 2018

Map Butterfly - Carte géographique 2018, Blanzay, France

16th September 2018

Overall this year has been very poor at our place for butterflies and moths with even our usual common species such as Speckled Wood, Meadow Brown, Large and Small Whites, Peacocks, Gatekeepers, Marbled Whites and Red Admirals all in short supply.

Early in the summer both types of Swallowtail made brief appearances as did Painted Ladies, a handful of Common Blue and Holly Blues whilst in June Some Lesser Purple Emperors graced us with their presence, always welcome as they come down from the treetops to search for minerals that they usually get from any excrement that is to be found. 

Click photos to expand.

Above -  Lesser Purple Emperor on dog excrement.

Anyway, the purpose of this little note is to mention one butterfly species that have been abundant here this year, in fact exceptionally so and that is the Map Butterfly, Araschnia levana, a pretty little butterfly that has two distinct forms, Araschnia.f. levana and Araschnia.f. prorsa that represent the spring and summer broods respectively. levana individuals are primarily orange in colour, giving them the appearance of a small fritillary, whereas prorsa individuals look more like a very small White Admiral and many people confuse them as such.


Above - Map butterflies 2nd generation

The eggs are laid in little strings bunched together under nettle leaves which are the caterpillar food plant in shaded or partially shaded areas. Late season caterpillars overwinter as pupae that emerge in the following April/May providing the first generation butterflies. The 2nd generation flies from June to August. In the South and Southwest of France a third generation may be produced in some years. The caterpillars in some stages bear some resemblance to Peacock caterpillars that share the same food plant of nettles so it’s worth a closer look.


 Above- Map butterfly caterpillar & Eggs


As mentioned there have never been so many here before for what has previously been a scarce species at our place where we rarely see more than a few in a season and it’s hard to see what if anything has changed. 

It is a species that may be benefitting from climate change, who knows? I'll see what happens next year.

Chris