Conservation Strategy for Amphibians in the Rhône-Alpes Region 76
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FRANCE JEAN-LUC GROSSI HERVÉ COFFRE AND ROGER MARCIAU Conservation strategy for amphibians in the Rhône-Alpes region 76 The year 2000 was probably the moment in France THE PROBLEM OF AMPHIBIAN MORTALITY when people became aware of the amphibian WHILE CROSSING ROADS DURING PREMATING MIGRATION tragedy currently taking place on a worldwide scale. An indication is the many newspaper This is the major cause of amphibian mortality as well as the most spectacular demonstration of their articles expressing the growing concern about the existence. Though very discreet during most of the extinction of many species and the decline of year, the amphibians migrate in massive numbers in the spring and the resulting slaughter on the roads amphibians noted around the world. produces a considerable effect on public opinion and has incited an array of environmental-protection groups to launch concrete action to protect the frogs. An article in Le “Monde”, one of the major daily newspapers in France, stated that “the decline of However, though campaigns to protect migrating amphibians around the world has been confirmed”. amphibians were initiated a number of years ago in Similarly, many specialised reviews such as National certain European countries (Belgium, Germany, Geographic published articles on environmental pol- Switzerland), it is just barely starting in France, if one lution that has led to the disappearance of a large does not count the eastern regions (Alsace and number of amphibians, particularly in Europe. With Lorraine) where the first attempts were started at the photographic evidence, they drew attention to the end of the 1980s. Figure 1. discovery of a population of frogs that have suffered There are solutions! The amphibian genetic damage (five legs), probably due to the com- Concerning the problem of roads, different solutions mortality while bined effect of a number of factors. These factors crossing roads is exist, depending on the local situation and the a great problem. included the pollution of humid zones, solar radia- importance of the problem encountered. A few of tion made more aggressive due to the increase in these solutions are listed below. greenhouse gasses and an overall increase in the “Amphibian” road signs to reduce speeds. The main fragility of amphibian populations rendering them sites may be equipped with “Amphibian” road signs more sensitive to a virus that had remained inoffen- to reduce the speed of cars. These signs may be the sive until now. standard “!” sign (caution/danger) with a smaller “Frogs” sign placed just below. Another possibility THE STATUS OF AMPHIBIANS IN FRANCE would be to create a “Frog crossing” sign. It should be noted that high speeds result in disproportion- All amphibians are protected by law in France. All ately high mortality rates because the animals are species are fully protected, with the exception of sucked in by the air currents. These signs have Rana temporaria and the Rana kl esculenta group. already demonstrated their effectiveness in These two species are partially protected to take into Switzerland and in Belgium and a further advantage account French cultural and gastronomic specifici- is that they reduce the risk of accidents because ties... and they may indeed be captured if they are to roads can become very slippery on major migration serve as food. In each part of the country, an official nights. document sets the dates during which frog hunting is authorised. Detours during migration periods. This solution is rarely feasible. The road is closed in those places and NUMBER OF AMPHIBIAN SPECIES per administrative sector on those nights that migrations take place (approxi- France 33 mately 15 nights per year). This is a highly effective Rhône-Alpes region 19 solution, but requires the full backing of the appro- Isère department 16 priate local-government body and maximum support on the part of the local population which must accept In addition to legal protection, the Muséum National a detour via a route less exposed to migrations. d’Histoire Naturelle (M.N.H.N.) published in 1995 the Red book on fauna in France. On the basis of criteria The creation of capture barriers. It is not possible to established by the U.I.C.N., this document indicates create a great number of barriers due to limited the status of the various species with information on human and financial resources. However, monitoring their degree of vulnerability. by capture is still necessary to acquire the basic data for a sustainable project. TOOLS IN PRESERVING BIODIVERSITY IN NEMORAL AND BOREONEMORAL BIOMES OF EUROPE NACONEX 2001 3 • RESTORATION AND ECOLOGICAL ENGENEERING Toad tunnels. These are tunnels created under LIST OF PRIORITY SPECIES roads. The amphibians are guided to the tunnel by an FOR CONSERVATION IN ISÈRE obstacle (wall, trench) positioned along the road. This type of installation is very expensive, but very Basing our efforts on over 30 years of observations in effective if the necessary study and design work are the department, an assessment of the various poten- put into the project. Monitoring by capture is there- tial threats to species was drawn up. To establish the fore required in the intial stages of the project. conservation priorities for the department, a number of different tools were used, notably the world (WCU- ISÈRE: AN EXPERIMENTAL DEPARTMENT IUCN, 1996), European and national red lists. IN THE RHÔNE-ALPES REGION In light of the national (or international) situation for certain species, Isère bears special responsibility 77 It was in 1994 that Espace Naturel de France (a fed- that goes well beyond departmental considerations. eration of all the nature conservation reserves in Four amphibian species would appear to be particu- France) launched a campaign to alert and inform larly threatened in Isère: • Triturus cristatus • people about the decline of wetlands. The mascot Bombina variegata • Hyla arborea • Pelodytes punc- selected for the campaign was, of course, an amphib- tatus ian and this marked the start of the “Frog channel”. At the same time, the Centre Ornithologique Rhône- Alpes continued its work on establishing the red list Figure 2. of land vertebrates in the Isère department. As a Triturus cristatus result, everything was in place in 1995 for the start of the first project in the Rhône-Alpes region in favour of amphibians. SUMMARY OF EVENTS IN SETTING UP (880 meters) in the THE PROJECT RNGL • Visit to sites in the Drôme, Rhône 1992 • 2nd capture and Loire barrier for • International Departments amphibians (600 Concerning amphibians, the rare Triturus cristatus is Conference in RIO • Visit to sites meters) • “Habitats” • 1 site equipped still to be found in Isère, but it is virtually absent in all • 1 site equipped Directive (400 m) in Savoie the departments surrounding Isère. Bombina varie- (900 m) in Savoie 92/43/EEC Department Department gata is present over the entire department, which 1994 2000 1998 makes Isère the last true bastion for the species in 1st communication • 8 equipped sites Information and the South of France. Concerning reptiles, Emys orbic- efforts via the “Frog in Isère visits to sites channel” Department ularis is today still fairly numerous in the northern •2 equipped sites • 5th capture 1995 in Isère part of the department, but that population group is barrier for Department • Publication of the amphibians (880 one of the last in the Rhône-Alpes region. As the • 3rd capture Red book meters) in the above examples make clear, it is imperative to initi- barrier for • Publication of the RNGL amphibians (880 ate conservation efforts for these species with high Isère Red list •1 site equipped meters) in the • Monitoring of (400 m) in Rhône environmental value. RNGL road kills 1996 Department • CORA study 1996 • 1 site equipped •CORA study (400 m) in Loire • Plan of action in •1 site equipped THE GRAND-LEMPS Department favour of reptiles (500 m) in Savoie •1 site equipped and amphibians Department POND NATURE RESERVE, A LABORATORY (400 m) in Savoie • 2 equipped sites • LPO study in Department IN THE RHÔNE-ALPES REGION in Isère Department Loire Department • 1st capture barrier for amphibians (250 1999 RNGL: Grand- This site, located between Lyons and Grenoble at an meters) • Decision on Lemps pond 1997 priorities Nature Reserve, altitude of 500 meters, was declared a national • 6 equipped sites CORA: Centre nature reserve in 1993 due to the wealth of bird • Road-kill study in in Isère 533 townships in Department Ornithologique wildlife and the many fens and moors. Isère • 4th capture Rhône-Alpes, • 2 equipped sites barrier for LPO: Bird Insufficiently evaluated amphibian populations. in Isère Department amphibians Protection League Though less well known, the amphibian population stands out for the fact that all four species of the Triturus genus (T. cristatus, vulgaris, helveticus and The work carried out in Isère since 1995 made it pos- alpestris) found in the region are present in this sin- sible to expand the ENF campaign to most of the gle zone. What is more, when questioned, elderly Rhône-Alpes region (in 1999, four other departments inhabitants in the area remembered that large num- launched the campaign and a number of sites were bers of Bufo bufo were killed on the road cutting equipped in 2000). The work on the methods through the wooded, western side of the reserve in employed and the monitoring of populations com- the 1940s and 1950s. The reserve management plemented the studies already carried out in Alsace organisation, the AVENIR agency, in conjunction with and in Europe and serve as an example for the scien- CORA Isère, quickly decided to initiate a program to tific community and associations in Rhône-Alpes. evaluate and save the amphibians in the reserve. TOOLS IN PRESERVING BIODIVERSITY IN NEMORAL AND BOREONEMORAL BIOMES OF EUROPE NACONEX 2001 The plan to capture the amphibians • There is a vast population of Triturus which came as In 1995, an assessment of the number of animals a surprise because very few were observed among killed on the local road and an examination of the rut- the animals killed, probably due to their small size.