Article by Christian Cauvet published in 2003 in the Bulletin de la Société herpétologique de France, No. 106, p. 26–32.
Reptiles and batracians in Vierville
End of the 20th century and disappearance of French herpes fauna
A testimony for the Calvados region of northern Bessin
Bull. Soc. Herp Fr. (2003) 106: 26-32
By Christian CAUVET 25 rue Domremy, 76000 ROUEN
The end of the 20th century was marked, in many French regions, by a dramatic reduction in reptile and batracian populations. Many rural landscapes have been radically modified by the evolution of cultivation practices. It is now impossible to guess that they could, only a few years ago, be totally different and shelter a fauna that has now disappeared. This is particularly the case with the fauna of reptiles and batracians and I think it may be useful for the SHF bulletin to also serve as a witness to these developments, so that future generations can find on its pages testimonies of the brutal changes in our environment. This is why I wanted, in a few lines, to be able to testify to my personal knowledge of the herpetofauna of a region and the evolution that was itss between the early 1980s and our first years of the 21stth century.
The region concerned is that of western Bessin, and in particular the area located behind the beaches nicknamed " Omaha" since the Allied landing of June 6, 1944, between the coast of the English Channel and the commune of Trévières, about ten kilometers inland. This region of Bessin was traditionally a cattle and dairy farming region because the rainfall of its climate favors the rapid growth of a fatty grass. The structure of the farms was therefore of the "bocager" type and adapted to these productions and this region was characterized by the abundance of small plots, often of one hectare or less, separated by slopes planted with hedges, frequently lined with ditches and often comprising one or more ponds intended for the drinking of cattle. This region was so characteristic, with other related to Calvados or the Manche, that we also spoke of a "battle of the hedges" to describe the fighting that took place in the first days following the landing in Normandy. However, this part of the interior has changed abruptly since the early 1990s, with the intensification of corn cultivation and the parallel felling of many hedges.
On the coastal cordon, a particular environment was also conducive to herpetofauna, consisting of gently sloping cliffs, delivered to tall grass, and a dune cordon, in the municipality of Saint Laurent, with a swampy area. This entire coastal area was, from the 1940s to the end of the 1960s, a kind of nature reserve, because, following the mining carried out by the Germans during the occupation, and because of the many ammunition abandoned after the landing, a certain fear of venturing there has long existed. The construction of many second homes only resumed from the 1970s, beginning the gradual destruction of coastal biotopes favorable to reptiles and batracians.
Born in the late 1950s, I found myself a teenager during the 1970s and my parents had a residence in this area. Passionate about all aquatic environments, I spent a lot of my time, cycling, exploring this region. At that time, I was able to identify a very rich herpetological fauna that was made up of many species.
The bocager environment with many ponds was indeed very favorable to the Batracians and the coastal area also to reptiles. Today, in 2002, most species of reptiles and batracians have almost disappeared or have become extremely rare for several reasons: on the one hand the evolution of cultural practices that have caused the disappearance, in less than twenty years, a large part of the hedges and slopes and almost all the ponds and water points, and on the other hand the increased use of the coastline and the construction of many second homes. You will therefore find below traced, some of my observations relating to the herpetofauna of this area (I noticed that this area referenced XIV-11 in the 1989 inventory of the SHF had been little or incompletely studied because many of the species I observed there are not referenced there)
Set up a puddle or a small pond in your garden: CLICK HERE
A small pond to welcome the garden animalsRead the rewritten text
This reading version has been rewritten from the newspaper clipping. Connecting phrases and any reconstructed words are not a verbatim quotation.
This gardening article proposes to create a water point, even very modest, to allow insects, birds, lizards and toads to drink, cool off or swim.
It recommends a sunny and quiet location, dug on a gentle slope ten, thirty, or even fifty centimeters deep, with irregular landings allowing small animals to descend and especially to come out easily. The surface can be limited to one square meter. The bottom is tapped and, if the ground allows water to escape too quickly, covered with a thick black plastic.
Stones of various sizes and branches joining the bank should offer rest and passages. The rains of early winter then fill the pond, which can accommodate frogs, dragonflies, salamanders and butterflies in spring.
The author advises to conserve mud, dead leaves, plant debris and branches, useful for food and refuges for small wildlife, rather than looking for a place that is too clean. The pond lives to the rhythm of the seasons, even reduced to mud in the summer. In case of complete drought, a stream of rainwater can be added without disturbing the animals. The photograph shows a pond in an English garden.
View the archive imageDownload the rewritten text
Original OCR text
The original OCR text is kept for comparison with the image. Its reading order and some words may be incorrect.
Reptiles: Four species were present with certainty: the Viper peliade (Vipera berus), theSlowworm (Fragile Anguis), the Viviparous lizard (Lacerta vivipara) and the Snake with collar (Natrix natrix). However, I have never noticed the presence of the Smooth Coronelle (Austrian Coronella), but his great natural discretion can explain it.
With regard to the vipere péliade, Vipera berus, this species was very abundant in the 1960s on the coastal area of cliffs in soft slopes, so much so that our parents forbade us to go play there because of the "snakes". It is true that it was enough to go a few meters off the paths to fall nose to nose with a "snake" (which was often just an orvet...). I even met several times peladic vipers on the beach (young people most of the time) who had descended along streams or who I think had been dragged into water drainage pipes from the inland marsh. Vipera berus was also frequently found along the slopes in the fields at the top of the cliffs or in the uncultivated area that borders the cliff. Today this species is still present but has become very rare and very discreet. His presence in Vierville sur mer was nevertheless proven to me in 2001 by the sight of an adult female killed per inhabitant of this commune, in May 2002 by the personal capture of a live juvenile specimen, about 18 cm, as well as by the observation in July 2002 of an adult male in the coastal area managed by the coastal conservatory near the American military cemetery, which despite its summer tourist attendance, therefore remains a place of refuge for herpetological fauna.
The orvet, Anguis fragilis, was even more common than the pelad viper and its presence accentuated the feeling of serpent proliferation in uncultivated areas. It is still relatively common and quite well known to secondary residents who respect it. Unfortunately, his meeting with ill-informed people is often fatal to him.
Lacerta vivipara (viviparous lizard) seems to have almost completely disappeared. However, it was quite abundant in all the slightly sunny places and in particular on the coastal strip, especially in pebble scree and on gently sloping cliffs, yet oriented towards the north. Its disappearance seems closely linked to the development of second homes on the coast and the multiplication of cats on its distribution area. I have very often observed domestic cats successfully hunting these lizards. However, it is possible that it still remains in certain specific places, especially in cliff scree and in uncultivated cliff edge areas. Far from homes, it is possible that it also owes its rarity to the predation of seagulls, or various raptors, more numerous today than twenty years ago.
The collar snake Natrix natrix was not very abundant but could be found regularly, not on the coastal area, but inside by the ponds. It probably also existed in the coastal swamp area of Saint Laurent sur mer. Today, the species seems to have almost completely disappeared with the filling of ponds and the gradual drying of the coastal marsh. However, the species is still present in the south of the area in the Trévières marsh where the wet ditches it loves are still numerous.
The batracians: Rather interested in the urodel batracians, my knowledge of them is much better than that of the anours also present. Among the urodels, were present with certainty: the Crested newt Triturus cristatus, the Punctuated or common newtTriturus vulgaris, the Palmed newt Triturus helveticus And the Alpeste newt Triturus alpestis As well as the Common salamander Salamandra salamandra. For anours, I can attest with certainty to the presence of the Common toad Bufo bufo, of the Green frog Hyla tree, Of Birthman toad Alytes ostetricans And of Red frogs Of the species Temporary frog. The exact identity of Green grnouiles Met is not known to me. As for Dalmatian frog, I cannot attest to his presence in the area. I have no certainty about the presence of Bufo calamita, the Toad of the reels And Bombina variegata, the Yellow-bellied belly, but I think that these two species must have been present in the coastal swamp of Saint Laurent, a biotope that was very favorable to them and comparable to other similar to Calvados (Ver sur mer and surroundings - Zone XV-11 of Atlas 89; Castanet & Guyétant,. 1989) where I noticed the presence of these two species. This swamp having undergone many drying up and is now largely filled and amputated by the construction of second homes, these two species are certainly extinct in the area.
Bufo Bufo was certainly the most visible species throughout the area, both coastal and inland. On rainy summer nights, the roads were literally invaded, and it was impossible to get around by car without crushing large quantities. Today, it is almost gone, for lack of having preserved its wet breeding sites, almost all filled.
Salamandra salamandra was also very abundant and also during rainy summer nights you could see dozens of them on the roads, where they paid a very heavy toll on car traffic. They were much less noticeable than toads because their shape and color confused them with dead leaves or pieces of branches and most people ignored their very important presence. At dawn, the crows rushed on the road to feed on their corpses which were therefore very quickly eliminated and could therefore not be observed. In the 1980s I often took my car on rainy nights to observe the salamanders, and, by driving full headlights at idle on the roads joining the municipalities of Formigny and Vierville sur mer or Saint Laurent sur mer, I could see their very abundant presence. Today, under identical conditions, it is very difficult and almost impossible to see a single one. However, there are still a few rare water holes where salamander larvae can be found in winter and spring, attesting to the subsistence of adults, but these last water holes are suspended and the almost total disappearance of the species seems close.
During my nocturnal prospecting, I also frequently found on the adult road of the birthing toad, Alytes obstetricans. It's been many years since I've seen one but maybe there are still a few specimens around some isolated ponds away from roads...
The green frog Hyla arborea was very abundant but had seen its population decrease sharply after the summer of 1976, which had been very dry. I still remember, before this year, walking along a slope planted with shrubs where you could see a frog almost every meter. The species has gradually regressed but it is still present because, on some favorable nights, we can still hear the song of isolated specimens. But it is certain that there is now very little reproduction in the area itself, given the scancy of water points. However, in July 2002, I noticed the presence of many tadpoles in a pond located on the side of the road and a cultivated field. Unfortunately, this is again a suspended pond, its neighbor in the same field having been filled during the winter of 2001/2002...
Red frogs Rana temporaria also became very rare while they were also omnipresent. Like toads and salamanders, they were "formerly" very many to be crushed at night on the roads in rainy weather.
The four species of newts known in northern France were present in abundance and populated almost all the ponds in the area: Triturus alpestris, Triturus cristatus, Triturus helveticus and Triturus vulgaris. The most common species was T. helveticus, closely followed by T. vulgaris. T. alpestris was present almost everywhere but in smaller quantities. As for Triturus cristatus, the least numerous, he could meet even in small ponds where his presence was a little unexpected. Some large ponds housed the four species and I remember spending long moments, in late spring or early summer, motionless at the edge of ponds with clear water, observing the pariades of these four species and in particular the crested newts. Today, dozens of ponds have been filled and those remaining favorable are very few and threatened. T. cristatus has become excessively rare, as has T. vulgaris and T. alpestris. T helveticus still resists and can be found very early in season in some ditches filled with water, where unfortunately juveniles do not have time to undergo their metamorphosis before drying up. I have never noticed the presence in this area of Triturus marmoratus, the marbled newt.
The observation made here for a limited region could unfortunately be the same for a large part of the Calvados department where hedges and ponds have regressed dramatically over the past two decades. In the Caen region, I also knew dozens of sites where reptiles and batracians can be observed. Today, this region has been totally "raked" by farmers greedy for large spaces and all these sites have disappeared..... despite the laws and decrees for the protection of wildlife.... In the city of Caen itself, in the middle of the racecourse called "La Prairie", you could still, in the 70s, and before the drainage work...find many Triturus vulgaris and helveticus.
We see here that on the ground, the publication of wildlife protection texts has a totally zero effect on urbanization and especially the evolution of agricultural practices: what can be the motivation of a farmer for the maintenance of a pond in the middle of a pasture converted into a wheat or corn field....
Can we still do something? A certain awareness seems to be made but it unfortunately seems to me to be mainly facade. I sometimes wrote to a local elected official from Calvados apparently sensitive to the evolution of landscapes and the disappearance of hedges to try to make him aware of the problem of wildlife that interests us. I'm still waiting for his answer....
For my part, I decided to contribute in my own way to the protection of the batracians by becoming the owner, at the other end of the Calvados department, in the Pays d'Auge, of a piece of livestock land, where I intend to restore the ponds that are still there and are abandoned, so, with the exception of Triturus marmoratus, we still find in their vicinity survivors of all the species of urodels in northern France (salamander, crested newt, palm, vulgar and alpine) as well as, among the anours, at least Hyla arborea, Rana temporaria and green frogs.
BIBLOGRAPHIC REFERENCES
Chestnut J. & Guyétant R. 1989 - Atlas of distribution of amphibians and reptiles of France. Herpetological Society of France. Paris. 191 p.