Monday, 6 April 2015

Glow-worms – Gardeners’ friends

Glow worms are great but many people never see them, perhaps because they simply aren't where they live or perhaps because there is too much light where they are.


We are fortunate at our place to have substantial numbers of them due in no small part to the habitat structure of our land but there is no reason why most people shouldn't have them in their garden in rural France, (or the UK for that matter) or that they shouldn't be anywhere else that isn't being constantly ploughed and sprayed. However where they have become locally extinct or absent it is difficult for them to re establish due to the fact that the females can’t fly and rarely move far from their birth place.

Generally they have a preference for longish grass, footpath and track edges, roadside verges and the base of hedgerows, anywhere in fact that provides nutrition for the larvae and somewhere for the female to be visible to males that are flying around looking for them.

They have a complete 4 stage metamorphosis, egg, larva, pupa and adult and the principle species to be found here is Lampyris noctiluca

Females having mated immediately lay their eggs and then die, a fairly common occurrence in the insect world.

The eggs, which are laid between June and September take up to 30 days to hatch at which point the larvae start to feed on snails and less frequently slugs which they continue to feed on for 1 or 2 years, even 3 sometimes. These delayed and staggered larval life spans allow for bad years and provide a sort of insurance. The larvae have pale spots at the rear edge of each segment. They move very slowly on the surface in search of prey and can sometimes be seen on paths in daylight. Otherwise they tend to be found under stones, pots and so on and may well be accompanied by a number of empty, unbroken snail shells. Larvae of females can emit a faint glow which may be visible on dark nights.

Video of a glowworm larva riding on the back of a snail to bite and inject the poison that is produced in the larva's intestine and is able to digest proteins. VIEW VIDEO

Click on images to enlarge.





The pupal stage only lasts 10 to 15 days and is not often encountered by people unless they are actively looking for them.

Male and Female adults are different in so much as only the males have wings and can fly, neither are thought to eat. 

Females have a similar appearance to the larvae but without the pale spots at the rear edge of each segment and with a pale line down the centre of their backs. They don’t move around very much spending their life either on the ground or clinging to a grass stalk to allow their glowing end to be visible at night They are rarely seen in daylight.  


Males are much smaller with dark brown or black wing cases and fly low at night searching for the glow of females.


From a conservation point of view we need to avoid pesticides at all costs and not be too fussy about having some snails in the garden or on our land. Even in smaller gardens it should be possible to make one part of the garden a snail zone with a rock feature and some favoured snail food. Finally we need to ensure that there isn't too much in the way of outside lights that may prevent the males from finding the females.

If you are in France it would be really helpful to complete the simple online recording form HERE


Extensive detailed information HERE
Chris   


Tuesday, 31 March 2015

Violet Oil Beetle in France

Oil beetles are another one of those species that not everyone is comfortable with due to their interesting life cycle which we’ll come to.


They belong to the genus Meloe which is a large group with some 35 species of Oil beetle in Europe and 15 in France although I’m not sure how rare some of them may be and they are also somewhat understudied according to OPIE. Certainly the commonest are the Black Oil Beetle Meloe proscarabaeus and the one I find at our place the Violet Oil Beetles, Meloe violaceus, and we sure have a lot of them, so many that it’s hard not to tread on them when walking among the trees where the Lesser celandines are flowering at the moment.

Click images to enlarge

Below: Newly emerged female before putting on weight.



Below: Female having put on weight. 



Below: Recently emerged male with pronounced kinked antennae.



Below: Another male, again showing pronounced kinked antennae.




They are a flightless beetle without functional wings, and shortened elytra, (modified, hardened front wings), and they have a very interesting life cycle as mentioned.  Soon after emergence in March / April the adult beetles mate after first putting on some weight. With both the Violet and Black Oil Beetle the males have kinked antennae which they use to hang on to the females antennae with during courtship.  Once coupled they remain attached with the male being dragged around for an hour or more. The female then lays her eggs in a small hollow she digs in the soil and when these hatch the larvae, (called triungulins as they have 3 hooks on each foot), climb up the vegetation and wait on a flower head for a passing bee to settle to which they attach themselves. Very few survive but those that do and manage to hitch a ride are taken back to the solitary bees’ nest where they consume the bees’ eggs and the nutrition that has been put there. They then pupate and emerge the following year.

Below: Violet Oil Beetles coupled.



Below: Violet Oil Beetle eating Celandine.





They are classified as cleptoparasites and not actually parasites.



“”Kleptoparasitism or cleptoparasitism (literally, parasitism by theft) is a form of feeding in which one animal takes prey or other food from another that has caught, collected, or otherwise prepared the food, including stored food (as in the case of cuckoo bees, which lay their eggs on the pollen masses made by other bees). The term is also used to describe the stealing of nest material or other inanimate objects from one animal by another.”      SOURCE

Despite this behaviour which some dislike they are a good indicator of the level of solitary bee activity where they are located for without them they can’t exist.

As can be seen in the photo Oil beetles often attract small midges which feed on the oil produced by the beetle but do it no harm.



Rugged Oil Beetle Meloe rugosus,  Mediterranean Oil Beetle Meloe mediterraneus and the Short-necked Oil beetle  Meloe brevicollis are some other well known but scarcer French Oil Beetles.

If in the UK Buglife are running a survey on Oil Beetles and would appreciate your help. 

BUGLIFE OIL BEETLE IDENTIFICATION GUIDE 

Chris



Wednesday, 18 March 2015

Horned Osmia ( Osmia cornuta )

Osmia cornuta is one of the first solitary bees to emerge in spring and as such is an important pollinator of fruit trees such as apricots, plums and almonds. Present in most of Europe, (not the north), it is a species that has disappeared from most areas of intensive agriculture, but it survives well in some urban areas, wastelands, public parks and gardens in particular areas. 


Given this living where we do in the intensive cereal lands I was extremely pleased to see a group of these about midday buzzing around the table on the patio in the sunshine. At first I thought they were Osmia bicolor with their bright orange abdomens and black head and thorax, not easy to see when they don’t settle. Anyway, a little later Lynne called me to say that a couple were kindly putting on a performance for me on the table and providing a photo opportunity. 

Please Click on images to enlarge. 






They are closely related to both Osmia bicolor the Two Coloured Mason Bee and Osmia rufa, the Red Mason Bee and they behave in much the same manner. The female builds a nest in an elongated hole, often in an old branch or some other piece of timber. The majority of the holes are between 5 to 8 mm in diameter and the nest is formed with a series of cells separated by clay partitions. Each cell contains a food reserve formed by a ball of pollen and nectar, on which an egg is laid. If the gallery is too long, a dirt cap is raised by the female to reduce its size. As a generalist pollen collector they will use what ever is available according to season, this is taken to the nest and mixed with regurgitated nectar to make the so called bee bread which is made into a pellet stuffed into the cavity.  When the cell is half full following 10 to 30 trips, the female lays an egg and builds a front wall with some clay and then repeats this until the tunnel is full with up to 15 eggs and then seals the outside with a clay plug. She repeats this for about two months building one nest after the other.



When the eggs hatch the one that were laid first which are to be females develop more slowly. When fully grown the larva spins a light brown thread cocoon and transforms into a pupa.

The bee is fully formed in late summer but remains where it is until the following spring.

The mortality rate is very high; perhaps 60% or more never get to fly and in part this is caused by Cocoxenus indagator, is which a ‘fruit fly’ and a cleptoparasite of Osmia species that lays its own eggs in the bees nest when the bee is away foraging. Having said that it’s built in to the numbers of eggs produced so nothing to be concerned about as long as the habitat requirements are met. 

Places used for nests include - Hollow stems; Galleries in walls, soft stones or soil; Gaps in window frames and drainage holes; Old galleries dug by other species of Hymenoptera; Natural or artificial galleries in timber with holes of a diameter of 8 to 10 mm; Sometimes even snail shells as with Osmia Bicolor. Galleries are thoroughly cleaned before any eggs are laid and can be used almost indefinitely. All of these locations are available at our place and with no chemicals or poisons they should go on to thrive.

Definitely one to look out for in France.

Chris

Thursday, 25 December 2014

La Réserve Naturelle du Pinail


Human activity has always changed the environment and in this article in 2014 I took a quick look at an extraordinary area that since 1980 has been the first and only State Nature Reserve in the Vienne departement of France, La Réserve Naturelle du Pinail which is located in the commune of Vouneuil-sur-Vienne, (86210). The Reserve is 30 km north-east from Poitiers and 15 km south from Chatellerault where it sits high on the plains between the river valleys of the Vienne and the Clain, at the north of the state owned Moulière forest. The reserve is well worth a visit, especially for people with an interest in Odonata, (Dragonflies and Damselflies) CONTINIUED HERE.

Chris

Friday, 19 December 2014

Harriers and their protection

It seems such a waste to restrict some of my articles to a limited audience when this blog and the web sites are viewed around the world and so I'm starting to put some on the web site.


This is Harriers and their protection from an article in 2014 for Living Magazine which is an English language magazine covering Poitou-Charentes, Dordogne, Vendée and Haute-Vienne in south west France.

The plains of Poitou-Charentes and Vendée whether they be the high open windswept areas such as those characterises by the areas to the north west and west of Poitiers towards Thouars and Parthenay or the vast low open wetlands of the Marais poitevin and coastline are especially suited to certain birds, some of which are under severe pressure at the European and National level making our region particularly important for their continued well being..............      

Living Magazine



Chris

Wednesday, 17 December 2014

Thistles and Dandelions

Very few people are neutral when it comes to certain native plants, (or weeds as they are often known as), especially the more robust and common types such as Dandelions and Thistles and I certainly don’t want them in my vegetable or flower beds. However they along with a few other native plants form the most important natural source of nutrition for many of our butterflies, bees, hoverflies and other flying insects growing as they do in a vast range of different habitats and are worth a second thought before trying to chop them down or poison them at every opportunity as is sadly the case in an increasingly tidy and over managed landscape here in France.

Click on pictures to enlarge.



Of course I don’t expect for one minute that anyone will suddenly think “Oh, I must grow some thistles or sow a dandelion patch” especially if they live in an urban environment or in very close proximity to their neighbours but I would like to encourage anyone with some land or with larger gardens to leave a few thistles and to perhaps let dandelions flower for a while just to see for themselves just how beneficial they are and how many different creatures use them.  



I also leave the seed heads to stand on all the plants in our fields which provide food for seed eating insects and birds throughout the autumn and winter months as well as providing a depth of ground cover for the birds that require it.




With this in mind I've compiled a simple web page with some photos of thistles and insects that have been mainly taken on our land.     CLICK HERE

Chris

Sunday, 23 November 2014

Asian Hornet nest in my apiary - 2014

Cheeky or what?

You may find this a bit hard to believe and it certainly is an eye opener but now the leaves have started to fall Lynne spotted this yesterday when I was out for the day – an Asian Hornet nest actually situated almost directly over one of my hives and no more than 30 metres from several others.Click on photos to enlarge.

So what does this tell us? It tells us that maybe, just maybe, the Asian Hornet isn’t quite as dangerous to honey bees as has been thought. It also tells us to always be very careful when drawing conclusions based on limited third party information that may lack a solid foundation or without knowing all the surrounding facts of any given situation, something we can all learn a lesson from.




Of course this doesn’t mean that they can’t be a problem in some circumstances and it may be that they are modifying their behaviour, adapting to local conditions and taking other prey or simply that one Asian Hornet nest won’t have a serious impact where there are a large number of hives. As I have mentioned many times I have seen Asian hornets present around my hives ever since 2006/2007 without observing them being anything other than a minor irritation for my bees.

This one with the one I removed earlier this year from an empty hive makes me wonder just how many nests there have been within flying range of my hives but this is certainly fascinating for me, you can’t beat first hand experience.

Asian Hornets in a Bee hive

Asian Hornet in France


Chris