Showing posts with label Moths. Show all posts
Showing posts with label Moths. Show all posts

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  


Saturday 21 October 2017

Hawk moths in France - a simple guide

  
In the UK the Sphingidae family of moths are commonly called Hawk moths and in France they all use the word Sphinx as part of their common name.

The simple list that is linked gives their names in English, Latin and French, the caterpillar food plant, annual generations and migratory status, (if any), and a link to photos & distribution for each species on Lepinet.



Chris

Monday 30 January 2017

Pine processionary moth and Napoleon 3rd of France

So now it's warmed up a bit following that rather nasty period of cold weather there are the inevitable sightings of Pine processionary moth, Thaumetopoea pityocampa, caterpillars and all the usual corresponding scare comments that we, our children, our dogs, cats and horses will all die if they so much as get near them and that the vets and hospitals all over France will be unable to cope. Let's face it there is nothing like a bit of shock and horror to lighten up our dull winter days.

Of course this is not to say that the caterpillars can't be a problem and that due diligence is required when walking anywhere near Pine trees, equally that logic would normally dictate that if you have a Pine tree in your garden and knowing this potential danger it may make sense to remove it - there are very few parts of France where they belong naturally. 200 years ago in most places you would have been hard pushed to find one in most areas and it is another example of how commercial / economic interests with the demand for softwoods and quick returns have changed both the landscape and the environment dramatically. We see a similar issue with Poplars being used in wetlands.
It was in fact Napoleon 3rd that in effect put in place the possibilities for this species of moth to spread across France with..
"la loi du 19 juin 1857, également appelée loi d'assainissement et de mise en culture des Landes de Gascogne, va encourager le drainage, la plantation de pins, le développement de l'économie sylvicole, tout en condamnant en l'espace d'une génération le système agro-pastoral"

which roughly translates as......

"The law of June 19, 1857, also called the law of sanitation and cultivation of the Landes de Gascogne, which will encourage the drainage, the planting of pine plantations and the development of an economy based on siviculture, while at the same time condemning in the space of a generation the pastoral system, (of small sheep farming that was carried out on the wetlands)."

Since that time Les Landes has become a massive region for the production of pine and there are corresponding plantations all across France all heavily infested with this Pine processionary moth. This combined with garden planting and climate change has made this one of the most successful species we have in France today.

As a footnote, the sheep farmers on the mairais or marshes of that region at that time would spend their days watching their flocks on stilts, now that's something to think about.



Berger landais


Chris




Wednesday 25 November 2015

Deaths head hawkmoth and Great Peacock moth.

OK, size isn’t everything but the two largest moths we find in France are quite spectacular in both adult form and caterpillar and as such I think are worth a mention, they rarely fail to rise a "wow" when someone finds one.


The Great Peacock Moth Saturnia pyri is the larger of the two and is Euorope largest moth with a wingspan of between 100 and 150mm, (4 to 6 inches), although some texts suggest that 200mm, (8inches), is possible.

Click on images to enlarge

Great Peacock Moth on my hand

   
This is a species with only one generation a year with the adults usually emerging from mid April to mid May when they devote their short life entirely to reproduction as they live for perhaps 7 days and have no requirement to take nutrition.

Pair of Great Peacock Moths mating



Specifically a virgin female finds a place in a bush or tree where she emits nightly sex pheromones which diffuse into the air which can be picked up by males from as far as 5 km who will home in on the scent, however only one male will get to mate with a female as coupling signals the end of the pheromone emissions and sexual attraction.

It's always worth looking at any outdoor twine door curtains for eggs.



Due to the lack of time the female who is already bursting with eggs will often lay them in the tree where she is as soon as they are fertilised which is like as not in close proximity to where she emerged from her chrysalis or cocoon which may even be the tree where she was an egg herself. In some ways it’s of little importance as the caterpillar will happily use a vast range of deciduous trees.  The caterpillar goes through 4 stages over 35 days before pupating and changes both body colour and the colour of the tubercles.

Caterpillar 1st stage, (Ardèche), Photo Daniel Morel.


Caterpillar last stage



They are to be found more or less all over France if there are trees although there are far fewer towards the north.


The next largest moth is the Deaths head hawkmoth, Acherontia atropos, with a wingspan of 90–130 mm (about 3.5 to 5 inches), which makes it the largest European Hawk moth, (Sphingidae).

Deaths head hawk moth Photo Philippe Mothiron.



Unlike the Great peacock this is not a French resident as such, (yet), but a migratory species par excellence from North Africa where it uses its huge wings to be carried on the air currents across the Mediterranean Sea

Generally the immigrants arrive in May-June and will reproduce in the warmer south of the country where a second generation may be produced in September or October. The caterpillars live for 3 to 5 weeks and the pupal stage can last for about 3 weeks or so.  Adult moths live for around 6 weeks and feed on plant and tree sugars, sugars from fallen fruits and of course most interestingly they can enter honey bee colonies and take uncapped honey even though they are attacked by guard bees at the entrance to some extent but not seriously, however the thick cuticle and resistance to venom allow them to enter the hive or other colony space. Apparently they are able to move about in hives unmolested because they mimic the scent of the bees. I’m not really sure how this works as each colony has its own unique scent.

Caterpillars go through three stages, feed principally on various nightshades, are frequently found on potato plants and can emit a loud click.

Death head hawk moth caterpillars




Caterpillars from the second batch will find it hard to pupate and even if they do they won’t survive the winter frosts.

Showing the skull like pattern on the thorax



The moths name is arrived at by the skull like pattern on the thorax and it’s another species that was considered to be evil or a harbinger of death. In France they were quickly dispatched and treated with Holy water. What with that and pesticides used these days on potato crops they haven’t had an easy time and numbers have reportedly fallen significantly although if there are declines in numbers we would probably have to look to Africa and the situation there.  On the plus side, this year has been exceptional in France with larger numbers of sightings of second generation caterpillars following a very mild winter and a warm, dry spring and summer although again we should be cautious as the growth of social media and abundance of modern phones with cameras may simply be bringing to light larger numbers that would otherwise be missed. 


Chris

Wednesday 19 February 2014

Bats and mushroom growing underground in France.

One thing I've learnt is that when you get out and about you never know what that day will bring and that was certainly the case again the other week when I went to do a bit of underground Bat recording organised by Samuel Ducept and Miguel Gailledrat of Vienne Nature. We met at the bureau at 9am which is early enough for me in winter and as soon as everyone was present set of in two vehicles, 5 people in each to go our separate ways for the day.


I must mention that for some unknown reason it seems that it’s mainly females in France that are “into” bats and Saturday was no exception. Other than Sam and Miguel I was the only male the other 7 being “girls”, (any female under about 35 or possibly 40 is a girl to me these days).

We were going to try and research some underground cavities that either hadn't been looked at before or hadn't been researched for several years. These are all old workings, principally underground quarries in the first instance to provide the limestone that was used to build the châteaus and houses and most were then used for other functions, storing food such as cheese if part of a large property or used as champignonnières – commercial mushroom production. This was the principle means of commercial mushroom production in France during the 19th century until the middle of the 20th century thanks to the ideal conditions they provided, a more or less constant temperature, easy to regulate air flow and a good level of humidity. The process is quite complex and rather than make gross errors I have linked to a good site below in French with some interesting old photos but all methods required the use of containers filled with compost made with a mix of manure and straw plus lime.

Click on photos to enlarge.





These old underground caves or cavities are always on private land, often some distance from a road and sadly many have become blocked or overgrown. Of course overgrown or even partially blocked isn't necessarily a problem for over wintering bats providing they still have reasonable access but it obviously reduces the ability to record numbers effectively. Inevitably for us it meant drawing several blanks which is always disappointing however we did manage to find and gain access to several caves of varying sizes over the course of the day even when it meant overcoming a few obstacles.






It’s probably not a surprise to anyone that these caves are used by all manner of other species besides bats and in two caves there was the unmistakable and all pervasive smell of fox and even a brief glimpse of one as it ran away from our lights. Large numbers of Peacock butterflies and literally hundreds if not thousands of Herald moths Scoliopteryx libatrix hibernating all over surfaces of one cave and even a small cluster of Eristalis tenax hoverflies in a shallow hole in the rock face. There are always small clouds of lethargic mosquitoes and other midges waiting for spring and even quite large numbers of chocolate coloured slugs in one cave.





Not all bats favour caves to over winter with many species using houses, buildings or cavities in forest trees. The common pipistrelle Pipistrellus pipistrellus, one of the commoner bats prefers buildings and when found in a cave it will usually be near the entrance as will be Barbastelle Barbastalla barbastellus. The Large and Small Horseshoe bats are to be more likely found far from the entrance in the warmer air where they can sometimes remain moderately active even flying around sometimes and as they are often not actually asleep greater care needs to be taken not to disturb them.

Totals for the day.


Greater Horseshoe bat    73
Lesser Horseshoe bat      12
Brown Long eared bat     5
Daubentons bats             8
Whiskered bat                42
Geoffroy's bat                23
Natterer's bat                  6
Bechstein's bat                5
Greater mouse-eared bat  33

Although there was a reasonable number of Greater Horseshoe bats they weren't in substantial groups.













Chris



Saturday 11 January 2014

What's hiding under the hive roof

I think it's best to start for non Bee keepers with a short explanation of a basic hive structure. Shown below is a French Dadant Ruchette which is basically a small starter hive and is exactly the same as a full size Dadant hive in design, Dadant being a style of hive.

The box structure at the bottom is called the Brood box which is where the bee colony lives. 

Next with the hole in the middle is the Crown board or the cover that goes over the bees. The hole in the center is for placing a syrup feeder over or for placing a block of fondant for the bees to eat. When not in use it is normal to close it with a small cover.

Finally standing on edge in this photo is the outer metal covered weatherproof lid. All very simple really.



From time to time I lift the outer lids on my active hives to check everything is OK and as it's quite common to find various creatures that have made it their home I thought I'd take a few photos over the last week to have a reference for the future and of course a bit of winter fun. 

Perhaps no great surprises but here they are:

Mottled shield bug Rhaphigaster nebulosa and Common European earwig  Forficula auricularia 


Heterogaster urticae Nettle Ground Bug and Aphanus rolandri.


Melanocoryphus albomaculatus, Seed bug 


Rhyparochromus vulgaris 


Ruby Tiger caterpillars Phragmatobia fuliginosa with Pupa below.



Seven spot ladybird Coccinella septempunctata


Anyphaena accentuata ??


Garden spider Araneus diadematus??


A nest of  four Wood Mice Apodemus sylvaticus (Mulot sylvestre in French)


Clubiona stagnatilis ?? 



Harvestman spider sp??


Leaf cutter bee "nest"


Weevil -  Larinus sp. (poss-turbinatus)


Agonopterix arenella a moth that hatches in the autumn and spends the winter as an adult and a mud nest of Auplopus carbonarius a solitary wasp that eats mostly spiders.


Asian Harlequin ladybird, an introduced species. 

Invasive Harlequin ladybird France

Reduvius personatus or the masked hunter, an Assasin bug that covers itself with dust and other particles in the Nymph stage.






Chris


Monday 30 December 2013

Twenty plume moth - Alucita-hexadactyla

Another house guest for the Christmas holiday fluttering round the room was a tiny 20 plume moth. These micro moths are so hard to see in any detail with the naked eye and I didn't manage to get the best of pictures. The English name of this unusual little moth is something of a misnomer as each wing is separated into 6 'plumes'. The scientific name is more accurate, meaning 'six-fingered'.



Called Ornéode du chèvrefeuille in French due to the fact that the caterpillars of this moth eat the flower buds and leaves of Lonicera - species of honeysuckle. 

The adult moths can be seen throughout the year and are known for overwintering in houses and other buildings.

Eggs are laid in May / June and caterpillars are to be seen mainly in June and July with Pupation taking place in July and August.  

Found throughout Continental Europe, Scandinavia and the UK it is a common species wherever honeysuckle plants are present.

Chris

Wednesday 4 December 2013

Spindle trees and a sunny December day.

The sun came out and stayed out today, the cold wind dropped for the first time in weeks, nice enough to take time out from cutting and clearing this afternoon and just have a stroll to see what's about, maybe have a closer look at some of the birds that have been flocking in the last few weeks, many drawn in by the farmers plowing and exposing easy pickings. There are some quite large gatherings of Starlings of a thousand or more which may not seem a lot for this species but it's been many years since I've seen such numbers here. Mixed flocks of finches in the hundreds, predominately chaffinch, with smaller flocks of goldfinch which tend to keep to themselves. Occasional groups of Lapwing and Golden Plover moving around and some good size groups of Skylarks flying up from the wheat and oil seed rape fields. Otherwise nothing of any interest, a handful of Bramling, the usual groups of tits, (Great, Blue and Long tailed), the occasional Stonechat and the resident Buzzards, Wrens and Robins.

This is the time of year to look for the eggs of the Brown Hairstreak butterfly on this years growth of Blackthorn which it uses more or less exclusively. It's a butterfly that is quite common throughout the wider region but isn't that common where I am given there is still a reasonable amount of Blackthorn dotted around but maybe the eggs suffer destruction from the flail or cutters which are used to smash any remaining hedgerows back here in late autumn.

Anyway while I was doing this I caught sight of some Spindle berries catching the sun with the pink outer covers popped open revealing the rich orange seeds - simply stunning and I'm easily distracted !


Spindle trees are prolific where I live and can be found throughout the region wherever there is a bit of native hedgerow left. The wood of the European Spindle Euonymus europaeus is very hard and as the English name implies one of it uses was for making wool spindles in both the UK and France although the French name Le Fusain or Fusain d'Europe translates to "charcoal" another one of its uses and highly regarded by artists.

The caterpillars of the Spindle Ermine moth quite often cause panic for people that don't understand them as they will frequently strip a tree of its leaves in spring. Needless to say the tree recovers and grows new leaves and the following year it all happens again.




The Kidney spot ladybird Chilocorus renipustulatus  or Coccinelle des saules, (Willow ladybird), in French is said to be widespread but not common and today I chanced on half a dozen on the Spindle.  I assume this is because the Spindle tree hosts Black bean aphids in winter which would provide them with nutrition.




Some Hoverfly species are still finding some nutrition when conditions allow, especially on dandelions that we can often find flowering even in the midst of winter. The "Marmalade" hoverfly, Episyrphus balteatus is a common species that overwinters in its adult stage and is relatively abundant this year. It is among the very few species of hoverflies capable of crushing pollen grains and feeding on them which must give it an edge when food is scarce.


A couple of other species I spotted today that overwinter as adults providing they survive were a rather tatty Red Admiral and a Green Shield Bug Palomena prasinathe. It's a species that changes colour in winter to brown and often enter houses and other buildings for shelter. They are completely harmless and feed on tree leaves, this one is on Field Maple. 



Chris