PASCAL FAVEROT WITH BENOÎT CASTANIER, LAURENT GIGOUT, PIERRE JOLY AND CLAUDE MIAUD Management of reproduction zones for amphibians 80

TECHNIQUES TO DEFINE GOALS proximity of one or more groups. Do MAINTAIN AND ACCORDING TO THE SPECIES not forget that natural silting makes RESTORE these shallow environments very tem- ENDANGERED ENCOUNTERED HABITATS porary in nature (they tend to fill in During the formulation of a manage- over a few decades) and conse- ment plan, certain criteria are decisive quently, restoration work is required. in determining the environmental The biological cycle. There are two value of the site and the species to be distinct phases in the biological cycle included in the management goals. The role played by amphibians in of most amphibians: the ecosystem and notably that of There are two main criteria: • an aquatic phase (egg and tadpole); tadpoles in the recycling and • the presence of rare or endangered • a land phase (young and adult ani- species, or those at the edge of their export of organic materials in mals) following the metamorphosis of known geographical zones; the tadpoles. Technical continental waters has now been • sites where numbers have dropped Manual nr 7 This cycle means that there are migra- clearly identified. What is more, sharply. tions between land and water. The conservation their organisation, often in small In the above situations, the overriding In addition to the spawning zones, site of remarkable populations, and their usefulness goal is to assist the existing popula- management must make sure that the nature sites tions. The development of species not requires different in gaining knowledge on the areas between the reproduction zones already on the site is highly uncertain. forms of action, evolution of species contribute to and the land habitats do not consti- It depends on the capacity of those including some their environmental value. The tute barriers to migration. that occasionally species to move to new sites and the necessitate the destruction of wetlands required use of heavy for their reproduction has resulted machinery. in the decline of many amphibian Calling on the Reproduction experience species, in spite of their protected zone: gained through status. In light of all the above, the males are the many present for one existing conservation and management month at the programs in the efforts are now required. beginning of the Rhône-Alpes spring, the region, this females just a article presents few days. the basic THE GENERAL information CYCLE, EXAMPLE OF required to BUFO BUFO. correctly restore a site.

Note The purpose Land habitat: here is not to forest, almost discuss the the entire year. problems facing amphibians in mires and marshes alone. This document Migration zone: covers the depending on subject in a more the weather general manner, conditions, the in light of the migration may many projects last nearly two where the goals weeks and cover include the one to two diversification of kilometers. habitats through the creation or deepening of waterholes.

TOOLS IN PRESERVING BIODIVERSITY IN NEMORAL AND BOREONEMORAL BIOMES OF EUROPE NACONEX 2001 3 • RESTORATION AND ECOLOGICAL ENGENEERING

Occupation of reproduction habitats and coexistence of species. Certain species may suffer when they must compete with others (Bufo calamita, Pelodytes punctatus). They tend to avoid competition with other species by settling in temporary sites such as puddles and dips in sandy substrata, etc. A waterhole measuring a few dozen square meters is the standard ele- 81 ment required for the creation of a reproduction zone for amphibians. The three categories opposite may be added to account for the diversity of the habitats occupied by the various species. The Bombina variegata (in the defensive position), a small toad of major importance in Europe.

THE STATUS OF THE SPECIES FOUND IN THE RHÔNE-ALPES REGION

name protection Habitat directive Red list Sites on gravel Alyte oobstetricans National Appendix IV Uncertain or sandy Bombina variegata National Appendix II Vulnerable substrata Bufo bufo National / Monitor Bufo calamita National Appendix IV Monitor Hyla arborea National Appendix IV Vulnerable Hyla meriodionalis National Appendix IV Monitor Pelodytes punctatus National / Vulnerable Pelobate cultripes National / Vulnerable Rana dalmatina National Appendix IV Monitor Rana temporaria and kl. esculenta Partial / / Rana lessonae Partial Appendix IV Monitor Rana perezi Partial / Monitor Rana ridibunda Partial / Monitor Temporary sites Salamandra salamandra National / Monitor in forests Salamandra lanzai National Appendix IV Uncertain Triturus alpestris National / Vulnerable Triturus cristatus National Appendix II Vulnerable Triturus helveticus National / Monitor Triturus vulgaris National / Monitor

Stagnant sites in REPRODUCTION DATES open land OF VARIOUS AMPHIBIANS ON THE UPPER RHÔNE RIVER (MORAND & JOLY, 1994) Feb. March April May June July Aug. Sep. Rana temporaria Rana dalmatina Bufo bufo Salamandra Salamandra Rana ridibunda Rana kl. esculenta Rana lessonae Triturus helveticus Triturus alpestris Triturus crristatus Hyla arborea Bufo calamita Pelodytes ponctatus Bombina variegata Alytes obstetricans

TOOLS IN PRESERVING BIODIVERSITY IN NEMORAL AND BOREONEMORAL BIOMES OF EUROPE NACONEX 2001 CONFIGURATION The incorrect “corridor” idea. OF THE HABITATS REQUIRED Amphibians use their sense of smell for orientation and travel in straight FOR THE REPRODUCTION lines. Consequently, they do not travel For habitat-diversification projects around ploughed land by following (creation of pools in swamp areas, the hedges. All potential obstacles in etc.), the success of the venture does their path must be taken into account. not depend on the presence of a Take into account “natural” migra- reproduction site alone. A complete tions. In alluvial zones, flooding con- configuration of habitats suited to the tributes to the “management” of 82 vital movements of the animals reproduction sites and settlement in Alyte obstetricans (migrations, search for reproduction new sectors, and are a positive factor (design J.P. Thomas) sites, etc.) is required. for mobile species, suited to unstable A fragmented habitat. For a given environments (Rana ridibunda). total number of square meters of open • the habitat is structured with a cen- tral site (the “continent”, for example water, a series of small sites offers CONFIGURATION a pond) ringed by a number of satel- more resources for amphibians than OF THE REPRODUCTION SITES one large site. The total length of lite waterholes (an “archipelago” of small pools). banks is greater and there are conse- Among the possible reproduction quently more sites for tadpoles. The Major factors in structuring the habi- sites for amphibians, the pool is prob- risks of predators and of a site drying tat : ably that used by the largest number up is spread over a number of water- • An “archipelago” of small pools is of species and is the easiest to create, better than a single large waterhole. if the ground can bear the weight of • Make every effort to limit the arrival excavation equipment. It may be used of fish likely to eat tadpoles and eggs in all environments with captive water by avoiding areas submerged during (silting marshes, mires, etc.), as well flooding and any links to waterfilled as in meadow environments. ditches. Shape and slope. There must be at • Select sites depending on their suit- least one gently sloping bank to ability for migrations (type of substra- enable the young animals to easily tum, existing obstacles, etc.) and the exit the water and to encourage the capacity of nearby land to serve as a growth of the bank vegetation that is habitat (woods, rocky areas, depend- required for the growth of the tad- ing on the species). poles. A steep bank can however be Concerning migration zones. The favourable for certain types of insects. “ARCHIPELAGO capacity of a population to travel from Note that over time, a number of CONTINENT” one reproduction site to another and SYSTEM factors (erosion, trampling by hoofed between reproduction and land sites This system is animals) will contribute to reducing required to holes. What is more, the diversity of should be managed. A well selected the slope. ensure the the created sites is a further parame- habitat must avoid all obstacles presence of the ter likely to increase the number of between sites and notably: Triturus cristatus species living in the area. • physical obstacles (walls, stone in the fences); area. The A network of sites. The stability of • roads which cause very high mortal- archipelago of populations depends on the links that ity rates (90% of a population is killed five pools created are created with a number of nearby on the site of the when it attempts to cross a road sites (compensation of local drops in Pierre-Vérots where there is one car per minute, CASE 1. foundation would numbers through migration). The according to Swiss data); • high seem to be capacity of a population to rapidly re- • rivers; percentage of indispensable. establish a positive trend is therefore • ploughed fields. gradual slopes improved when: (nearly 100%). Migration is facilitated in sheltered CASE 2. • there is a network of potential repro- • large area duction sites not far from each other environments (hedges, woods) or on required. • 20 to 35% of (from a few dozen to a few hundred grassy substrata (see the figure • easier gradual slopes. • small area meters); below). coexistence of species. required. * numerous * coexistence spawning sites. between species • high risk of not easy. water drying up • small number or high cost. of spawning sites but cost probably lower.

TOOLS IN PRESERVING BIODIVERSITY IN NEMORAL AND BOREONEMORAL BIOMES OF EUROPE NACONEX 2001 3 • RESTORATION AND ECOLOGICAL ENGENEERING

This profile makes it possible to increase the depth while maintaining gradual slopes, It was used in the Charvas marshes.

Depth. The depth must be sufficient to For a pool 100 square meters in size maintain water during the entire time with a maximum depth of 1.5 meters the tadpoles are developing. and if the earth does not need to be Two version of Depending on the local conditions, a transported, the cost is approximately pools created minimum of three months with water 380 euros (before VAT). near [FB1]the is required. A waterhole that dries up This cost increases significantly if the Saint-Louis pond at the end of the month of August has soil is peaty and cannot bear heavy (Tricastin). The size of the open- no particular impact on the cycle of equipment because access is more the amphibians and is a means to limit water area had difficult and the work takes more time. significantly the presence of dangerous fish. Possible funding through compensa- drecreased in A depth of 1.2 meters was created in tion measures. Many “substitution” just a few decades. The the Dombes and the Charvas marshes. pools have been created in the frame- first year, the Encouraging vegetation on the work of infrastructure projects (e.g. shape and banks. Nearby trees contribute to roads) that disrupt the migration of profile were eutrophication of the pool (particu- certain amphibians. These measures designed simply larly alder trees) and reduce the pene- may also apply to temporary water- to evaluate the tration of sunlight which is an impor- holes and endangered species. technical difficulties. The tant factor in oxygenating the water. It following year, a is preferable to clear the surrounding ADJACENT HABITATS more elaborate area. SUITABLE FOR HIGH-VALUE design was Aquatic vegetation. The eggs of many implemented. species are laid on or among the Temporary sites such as ruts and leaves of the aquatic plants which are ditches in forests. A management These sites with temporary pools are a also a source of food for the tadpoles. plan specifically for these micro- low-cost habitat for species with high Glyceria, Potamogeton and Carex are biotopes would be difficult to imple- environmental value. In certain cases, particularly suitable and may be ment. Their temporary nature and these sites are indispensable addi- planted in reasonable quantities to uncertain use by the animals would tions to the network of sites occupied avoid the arrival of undesirable float- require numerous interventions. by a metapopulation. ing plants that cover the water. Periodic maintenance is required. However, a part of the management The negotiations with the site owner plan may attempt to preserve these or operator (for quarries) must target: Water quality. Water quality is appar- nearby forest micro-environments ently not a decisive factor unless the • maintaining sandy banks with vege- that are often found near marshes and pH is under 4. tation over 20 to 30% of the surface, fens. For example, they may comprise next to the spawning zone and prefer- Spreading the earth. A mound along a network of ditches and temporary ably exposed to the south and west. the edge of the pool may cause diffi- waterholes found among copses of This area will serve as the hunting culties (mowing), but reduces the cost alder or birch trees. It may be neces- ground, the daytime quarters and the of transporting the removed earth. sary to maintain or to create suffi- winter habitat; The costs. A major part of the cost is ciently deep ruts in unused roads or • maintaining a low area to receive incurred when heavy excavation ditches along them. run-off water, with little vegetation, equipment is required. When the The purpose is to maintain sufficient intended as the reproduction zone earth must be moved any distance, water for the development of the tad- (plants are however useful for the the costs rise sharply and there are poles and their design must take into spawn of the Bombinus variegata or legal problems (see Technical Manual account the configuration of the land- Pelodytes punctatus). number· nine; scape mentioned above. The end of commercial operations on • by the cubic meter of earth dug and Sites on sandy or gravel substrata. the site remains the greatest problem spread. Abandoned stone and gravel quarries because the areas with heavy vegeta- Average price for regional projects: as well as other sites with sandy or tion must be regularly cleared. 3.00 to 4.50 euros (before VAT) per gravel substrata are ideal for the Caution is required for limestone sub- cubic meter of earth removed and Alytes obstetricans, Bufo calamita and strata because the temperature of the spread. Pelobate cultripes or even Bombina water rises faster and greater depths • 50.00 euros (before VAT) per hour. variegata or Pelodytes punctatus. may be necessary.

TOOLS IN PRESERVING BIODIVERSITY IN NEMORAL AND BOREONEMORAL BIOMES OF EUROPE NACONEX 2001 replaces a major part of the manual from Aster, 155 cours Bérriat, 38028 intervention required to clear the Grenoble Cedex 1. area. Background material : The manage- The most palatable plants (Glyceria, ment plans and activity reports for the Typha, etc.) are consumed. However, project sites in the Rhône-Alpes Pelobate caution is advised concerning imple- region. cultripes. (design mentation of an extensive grazing J.P. Thomas) plan. A number of watering points are required for the herd or water pumps PROJECTS IN THE must be installed to provide the nec- RHÔNE-ALPES REGION 84 essary volumes. MONITORING AMPHIBIAN Generally speaking, the livestock The point here is not to list all the SITES AND POPULATIONS should have access to only a part of waterholes created, but rather to the pool. highlight a series of projects with Once a waterhole has been created or major amphibian importance, each Monitoring of amphibian popula- restored, the project gradually shifts implemented on a scale going beyond tions. Preparation of reproduction to regular monitoring and mainte- the individual pools and impacting on sites for amphibians contributes to nance. The goal of these two activities entire populations. maintaining biological diversity. The is to maintain the favourable situation effectiveness of the recommended newly re-established and to assess management techniques depends on whether the management policies are a high level of knowledge concerning effective. These are important aspects both the population and the organisa- and must obviously take into account tion of the created sites. To that end, a range of factors, not only the an initial assessment prior to any work LYON amphibians. and scientific monitoring afterwards Periodicity of interventions. are indispensable. There are two Waterholes often require very little types of evaluation. • Qualitative evaluation is fairly easy to carry out. Concerning toads and frogs, it is necessary simply to listen. A net with fine mesh may be used for the Triturus. This form of evaluation is Twelve pools created. The double used primarily for high-value species goal is to maintain species (Rana dal- and provides a rough idea on the pop- matina and three Triturus species) and ulation (number of croakers). gain knowledge through experiments, • Quantitative evaluation is more in collaboration with the University of complex and requires precise monitor- Lyons (Claude Bernard). Manager: ing instructions, regular visits accord- Fondation P.Vérots, Praillebard, ing to an itinerary that does not F-011390 St-Jean-de-Thurigneux change from one year to another (the transects or paths must be planned) and prior determination of the periods of greatest presence. AIN Quantitative monitoring is generally Excavation of the maintenance. Except in special cases, indispensable to ensure correct LYON central zone and dredging of mud is required once assessment of the impact of the man- grading along every 20 to 30 years, on average. The agement system on the existing popu- the edges to create gradual most favourable period for the batra- lations. slopes for the chians is from August to February, the pools in the best month being September. Boîtray marsh Work is required on the aquatic vege- TO LEARN MORE extended the wet tation if it is particularly dense. The period and ABOUT AMPHIBIAN increased the vegetation must be scythed, selected ECOLOGY presence of and any undesirable plants must be * The “botasses” in Sandrans. A vegetation. Most removed. conservation experiment in which Reviews and guides. “Les amphibiens of the pools in the Dombes region were Trimming or even cutting of trees may de France” by R. Guyetant, Revue maintenance restored (FGER funding). Managed by work is be necessary, depending on the local française d’aquariologie, first and sec- the Sandrans CUMA and the Chamber automatic, due environment of the pool. However, ond quarters of 1986. The various of agriculture (Ain department). to the major this work is also relatively infrequent. amphibian identification guides fluctuations in Information campaign in 1995 for Site maintenance by grazing? edited by Solar et Delachaux. the water levels, farmers and restoration work in notably the high Extensive grazing may be a useful Video. La grenouille et le crapaud et 1996.Manager: levels in the means to maintain the aquatic vegeta- La salamandre et le triton”, directed Chambre d'agriculture de l’Ain, winter. tion in spite of the resulting trampling by J.-P. Macchioni, coproduced by antenne Dombes and the increase in organic material. It Aster Les films du silence, available F-01330 Villars-les-Dombes

TOOLS IN PRESERVING BIODIVERSITY IN NEMORAL AND BOREONEMORAL BIOMES OF EUROPE NACONEX 2001 3 • RESTORATION AND ECOLOGICAL ENGENEERING

The Montfort marshes (Crolles). Management of the “chantournes” PASCAL FAVEROT (scything, etc.) for amphibian and WITH BENOÎT CASTANIER, RHÔNE floristic goals. LAURENT GIGOUT, PIERRE JOLY LYON The Herretang mire (St-Laurent-du- AND CLAUDE MIAUD Pont, St-Joseph-de-Rivière). Grading and management of former peat- First published: Cahier technique n° 7, extraction sites. The shallowest of the 1999. Editors : Conservatoire Rhône- sites are the most used by the Alpes des Espaces Naturels with financial support from la Région amphibians. Rhône-Alpes, Nature et découverte Manager: and la Direction régionale de 85 AVENIR, 10 rue Raspail l’Environnement de Rhône-Alpes. F-38000 Grenoble CREN * The Boîtray marshes (St-Georges- La Maison Forte de-Reneins). In 1997, grading work 2, rue des Vallières, and excavation of four pools and 1000 F-69390 Vourles, France meters of canal between the Saône E-mail: [email protected] river and the marsh. This work is part LYON SAVOIE of a larger project for water manage- ment in the marshes. Manager: CREN

LYON The marshes (Chindrieux...) On a silt substratum, excavation of a former branch of the Séran river and creation of three satellite pools to extend the habitat and a pond with very shallow and muddy edges. On a DRÔME peat substratum, excavation of three pools to restore the semi-aquatic environment. Manager: EID, chemin de la Tour, * The St-Louis Pond (Suze-la-Rousse) F-73310 Chindrieux Creation of open-water areas in a pond choked with vegetation. Manager: CREN, General Council of the Drôme Department and et SCI Saint-Louis Pond. LYON SAVOIE

LYON

The Maurienne valley. Creation of ISÈRE pools in Saint-Rémy-de-Maurienne and on the Hurtières plain, as com- pensation measures in the framework of the A43 highway project. The major concerns were the amphibians, prima- rily the large population of Bufo bufo The Charvas marsh (Villette d’Anton). calamita Nine “substitution” pools created as The Bassin Mollard marshes (Aiton.) compensation measures in the frame- Grading of tarns using heavy excava- work of the TGV high-speed train and tion equipment. A432 highway projects. The goal was The Aiguebelette lake. Creation of to avoid obliging the batrachians to numerous pools in Nances, Saint- cross the highway. The results were Alban-de-Monbel and Lépin-le-Lac. positive for all species except the Bufo Manager: bufo. CPNS, Le Prieuré F-73372 Bourget-du-Lac

TOOLS IN PRESERVING BIODIVERSITY IN NEMORAL AND BOREONEMORAL BIOMES OF EUROPE NACONEX 2001