Conservation genetics of the white-clawed crayfishAustropotamobius pallipes: The usefulness of the mitochondrial DNA marker

Abstract

The white-clawed crayfish, Austropotamobius pallipes pallipes, still has a wide-spread distribution in France, but since the last century, populations have declined because of habitat alteration (due to human disturbance) and have been also eliminated by crayfish plague, for which introduced exotic species are a vector. Action plans for the conservation of A. pallipes are urgent and if recovery programmes are to be initiated in France, then it is important to estimate how much genetic variation is partitioned between remaining populations as the species is being currently threatened in all its European distribution. We show how a new molecular marker can be used to study crayfish populations. Mitochondrial DNA (mtDNA) variation in natural populations was examined by restriction fragment length polymorphism analysis in samples taken from fifteen French populations and six European populations representative of three subspecies observed in A. pallipes in order to examine the extent of differentiation between populations. Biogeographic considerations about the genetic distances observed between the three subspecies are made. The study reveals a low level of genetic variation among English, Welsh and most of French populations, corresponding to a genetic stock uniformity among A. pallipes pallipes.The only two French populations exhibiting a high level of intrapopulational genetic variation are in fact mixed samples : the comparison with results obtained in European populations revealed that the first population was composed of the two subspecies A. pallipes pallipes and A. pallipes italicus and the second of A. pallipes italicus and A. pallipes lusitanicus.Results proved that some repopulations, performed in the past from A. pallipes italicus and supposed having failed, have been successful and that the French stock did not correspond to the only subspecies A. pallipes pallipes. A first analysis of genetic variance observed on a regional scale revealed that there was no genetic structure according to basins and could reflect human-mediated movement of crayfish stocks between these basins. Consequently, mtDNA is an essential marker to GÉNÉTIQUE ET CONSERVATION DE L'ÉCREVISSE À PATTES BLANCHES AUSTROPOTAMOBIUS PALLIPES : UTILITÉ DU MARQUEUR MITOCHONDRIAL.RÉSUMÉ L'écrevisse à pattes blanches Austropotamobius pallipes pallipes a encore une large répartition en France mais, depuis le siècle dernier, les populations ont été sérieusement réduites à cause de la dégradation des habitats suite à l'activité humaine et ont également été décimées par la peste de l'écrevisse, suite aux introductions d'espèces d'écrevisses exotiques. Si des actions de conservation d'A. pallipes sont urgentes à mettre en place, elles ne peuvent se faire sans une estimation préalable de la variabilité génétique des populations chez cette espèce actuellement en voie de disparition. La variabilité de l'ADN mitochondrial (ADNmt) dans les populations naturelles est examinée par polymorphisme de la longueur des fragments de restriction à partir...

Distribution of Crayfish in Europe and Some Adjoining Countries

“…SANTUCCI et al (1997) using electrophoretic techniques detected three population groups corresponding to A. torrentium, A. pallipes and A. italicus from various parts of Europe, but did not confirm A. lusitanicus as being a separate species. SOUTY-GROSSET et al (1997 and GRANDJEAN et al (2001a), however, using molecular markers, confirmed the subspecific status of A. p. pallipes, A. p. italicus and A. p. lusitanicus. Using morphological, electrophoretic and molecular techniques, LÖRTSCHER et al (1997) andLARGIADÈR et al (2000) confirmed BOTT's (1972) Austropotamobius berndhauseri for southern Switzerland.…”

“…There is some genetic evidence for this viewpoint (e.g. SANTUCCI et al, 1997;SOUTY-GROSSET et al, 1997;GRANDJEAN and SOUTY-GROSSET, 2000;GRANDJEAN et al, 2001b).…”

Mitochondrial and Microsatellite Dna Analyses of Austropotamobius Pallipes Populations in South Tyrol (Italy) and Tyrol (Austria)

“…In order to define efficient conservation strategies, accurate data on systematics and population structure are crucial (SOUTY-GROSSET et al, 1997, SOUTY-GROSSET, GRANDJEAN andGOUIN, 2003). Although A. pallipes populations were shown to display great degrees of morphological and genetic diversity in the Alpine region (LARGIADÈR et al, 2000;LÖRTSCHER et al, 1997;SANTUCCI et al, 1997), nothing is known about the phylogenetic status and genetic composition of crayfish populations in South Tyrol.…”

Assessment of Dna Variations of the Noble Crayfish (Astacus Astacus L.) in Germany and Poland Using Inter-Simple Sequence Repeats (Issrs)

“…During the last decade molecular techniques revealing a higher degree of variability have been developed and applied successfully in population studies of freshwater crayfish. Genetic differentiation of populations had been assessed using mitochondrial DNA (SOUTY-GROSSET et al, 1997;LARGIADER et al, 2000), RAPD-PCR (MACARANAS et al, 1995;SCHULZ, 2000;GOUIN et al, 2001), AFLP (FETZNER and CRANDALL, 1999) and microsatellites (GOUIN et al, 2000;EDSMAN et al, 2002;GOUIN et al, 2002). Phylogenetic studies MUNASINGHE et al, 2003), and reconstruction of the phylogeography were possible using mitochondrial DNA.…”