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



Monday 17 February 2014

Spring is in the air - well almost.

Not quite out of the woods yet with a sharp cold spell always possible ‘til mid March but today after all the rain the sun is finally shining, 11°C+ in the shade and life is emerging again even if perhaps only briefly taking a break from hibernation for some creatures.

I have to confess that this is always a somewhat nervous time of year for me waiting to see how many of my occupied bee hives are active. Even though activity in itself is no sure sign that the colony is OK and has a good Queen it’s quite a good indication if they are taking in pollen but even now if a Queen fails before the end of March there is no chance of a naturally mated successor. Most of the hives looked good, all were active and I even managed to get my first sting of the year right on the face, not too happy about that I have to say, never a pleasant experience however much it goes with the job.

Butterflies today were much as to be expected, all the common over wintering species, Brimstone, Comma, Peacock and Red Admiral but good to see them however common they are, after all it wasn't so long ago that the Small Tortoiseshell was a common species in our region, now it's getting quite rare. Also saw a Humming bird hawk moth a species that didn't over winter in our region at one time but increasingly some do now. Carpenter bees are always early risers on a warm sunny day and there were a few of them around “inspecting holes” although it’s hard to believe they could really be laying eggs at this time of year. Found this very pretty and immaculate Ground beetle with very orange legs.

Click on photos to enlarge.






Hazel catkins have been open a while now and many have been washed out with all the rain, none the less there are plenty that are fresh with pollen, goat willow is starting to show and will be open in a matter of days as is the wild plumb blossom.




Found some quite nice clumps of Agile frog spawn, perhaps a little early due to the mild wet winter so far……





…… and at 4.30 a few groups of Cranes totalling some 400 flew over chattering their way north east, (recorded on line with the LPO). All in all a pleasant day with the promise of the big spring rush just around the corner.

Chris

Monday 10 February 2014

Guillemot, Razorbill and Puffin die in their thousands.

Much has been made of the human situation recently with flooding and all that goes with it but additionally the recent rain and persistent Atlantic storms have had severe consequences for wildlife in many places, not least the Atlantic coast of France where thousands of birds have been washed up on the coastline in recent days.

Principally Guillemot, Razorbill and Puffin the main cause of death is from exhaustion and lack of food according to analyses carried out at Nantes, although there have been some with traces of oil that may be from the ships that leaked fuel after running aground.

Hegalaldia, (Centre de sauvegarde faune sauvage du Pays Basque) have taken in 85 birds to date with the League for the Protection of Birds (LPO) and other sources indicating that as many as 500 in Loire-Atlantique, 500 in Vendée, 1000 in Charente-Maritime and more than a thousand on the rest of the coast have been affected.

With the sea “like a giant washng machine” there is too much swell and reduced visibility for these birds to fish and following three weeks of these conditions the recent surge has driven these birds on to the coast where they have been beached after fighting for days and days to survive.

Although Atlantic storms are “the norm” for the west coast of France the difference in this situation which is being experienced by everyone affected is the duration and strength of these storms.


UPDATE.

As of the 18th February it is estimated that over 11 000 birds were stranded along the Atlantic coast, the main species being affected are Puffin (over 8,000 individuals) , followed by Guillemot.  Among all these beached birds some were ringed and they come mainly from the United Kingdom.

The statistical report is still provisional.

It should be noted that the exceptional nature of this mass stranding has never been observed before  in France other than by marine pollution.

Every winter illegal discharges from ships are recorded off the French coast, and now following successive storms the Atlantic coast is witnessing the arrival of tar balls. Increasingly oiled birds are reported.

It is probable that more birds will be found on the Atlantic coast throughout the month of February.

As of the 25th February 34,121 birds dead and 2,784 sent to rescue center. Many birds floating off the coast have been reported by fishermen. The still provisional toll is likely to rise in the coming days.

Photos from LPO France.  Click on photos to enlarge.













Chris