Lynx Distribution in the French Alps (1995-1999)
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Hystrix It. J. Marnrn. (n.s.) 12 (2) (2001): 11-15 LYNX DISTRIBUTION IN THE FRENCH ALPS (1995-1999) PHILIPPE STAHL AND JEAN-MICHEL VANDEL Office national de la chasse et de la faune sauvage, Birieux, 01250 France ABSTRACT - From 1995 to 1999, 69 data were recorded on lynx presence in the French Alps, in an area of3,636 km2.Lynx presence was recorded in the major forested regions oftlie prC-Alpes (Chablais, Gli&re/Aravis,Bauges, Chartreuse, Vercors, Diois/Beauchkne),in the Chamonix and Maurienne valleys and the Brianqon region, but no large continuous area of presence was shown. Lynx have probably been permanently present in certain locations during the past years, but the presence of a large lynx popula- tion in the Alps is improbable in the northern French Alps. In the future, we recommend that habitat sui- tability for lynx in the northern French-Alps should be assessed, together with possibilities of connec- tion between alpine regions and possible bias in the monitoring system. Key words: Lynx lynx, monitoring, distribution, Alps, France. INTRODUCTION 1999) of the lynx in the French Alps and make At the onset of the 20th century, after a long a few comments on the future of lynx man- period of decline, the Eurasian lynx Lynx lynx agement in that region. had become virtually extinct in France, like LYNX MONITORING IN FRANCE in most other West European countries. Nowa- days, the species is slowly recovering in some In France, monitoring of the lynx population parts of its previous range. In France, the lynx and census of livestock losses have been en- has expanded its range in the Jura and in the trusted to the “Office national de la chasse et Vosges (Stahl etal. 2000,2401). In the 1970’s, de la faune sauvage” (ONCFS), the national lynx have also spread towards the French Alps game and wildlife agency of the Ministry of from Switzerland, where at least 14 individ- Environment. Data are collected with the help uals had been reintroduced (Breitenmoser et of a permanent Large Carnivore Expert Group al., 1998). The 1974-1997 lynx distribution (LCEG). The LCEG has two main objectives: survey in the French Alps (Stahl and Vandel, (i) to investigate all livestock predation events, 1998) showed a southward expansion of about to enable payments of compensation for lynx- 200 km, but no continuous distribution area, caused damages and (ii) to collect and veri- and most data were scattered and collected in fy signs of lynx presence (tracks, prey re- distant places. At that time, this distribution mains, sightings, scats) useful for monitoring pattern was partly explained by an insufficient the changes in its distribution. In each ad- observation effort in the French Alps (Stahl ministrative unit of some 5000 km2 (called and Vandel, 1998). At the first Conference on “dkpartement” in France), 30-60 local lynx- the Status and Conservation of the Alpine experts are permanent members of LCEG. Lynx Population (SCALP) in Engelberg Most experts are agents of wildlife or forestry (Council ofEurope, 1998), the need for more public agencies, or national parks. These peo- careful monitoring of lynx populations was ple have attended a training course and are emphasised. Over the last five years we have able to identify lynx signs. They investigate tried to make such an effort in France. In this each case of domestic livestock predation. paper, we will give a short overview of the They may search for other lynx signs in the present-day knowledge of the status (1 995- field (tracks, prey remains), but their main 12 P. Stahl and J.M. Vandel Table 1 - Lynx presence data collected in the French Alps over the last ten years (hard facts: captures, dead lynx, photos); confirmed observations: livestock kills, wildlife kills, tracks, scats, hair, confirmed by a lynx-expert, sightings made by Iynx-experts; unconfirmed observations: livestock kills, wildlife kills, tracks, scats, hair, single footprints, sightings or calls, for which lynx-experts consider that they are “probable” lynx signs. Categories 1990- I994 1995- I999 total hard facts 2 0 2 confirmed observations 5 7 12 unconfirmed observations 24 62 86 TOTAL 31 69 100 activity is to collect and verify all informa- re/Aravis, Bauges, Chartreuse, Vercors, tion reported by hunters, foresters, shepherds Diois/Beauchhe). To the East, in alpine val- or the general public. Each category of field leys, lynx presence was recorded in the Cha- sign is noted on a special form. Objective and monix and Maurienne valleys, and the Brian- standardised identification and reliability as- $on region, but not in Beaufortin nor in the sessment criteria have been defined for each Tarentaise valley (Fig. 1). category of field sign (Vandel and Stahl, In each region, only a few data points were 1998). Data are collected in each “d6parte- collected and they were rather sparse. Nev- ment” and then transmitted and analysed at ertheless, in seven of the 11 more or less the national level by ONCFS. For range es- isolated areas (Table 2; Fig. l), lynx signs timates, each data point is centred within a 3 were recorded in 2 3 years of the five-year km x 3 km square. At such a small-scale, we study period, suggesting a regular presence are only interested in presence-absence data of lynx. As in 1990-1994, lynx attacks on in each grid. Lynx “presence” in a grid is ex- livestock were only rarely recorded and tended to the nine surrounding grids (i.e. a confirmed. total of 8,100 ha for each data or 1/2 to 1/3 of an average lynx home range). Range esti- DISCUSSION mates are obtained by summing occupied Lynx distribution grids. This method is less susceptible to the All French lynx populations are still vulner- effects of outliers and does not include non- able. Nevertheless, the future of the Jura and used areas. Nevertheless, the range estimates Vosges borderland populations does not seem are very conservative. to be so bad (Vandel and Wecker, 1995; Van- del and Stahl, 1998b; Stahl and Vandel, 1999). LYNX DISTRIBUTION In the French Alps, the future of the lynx is The number of data points increased from 3 1 much more debatable. The reasons for the ab- in 1990-94 to 69 in 1995-1999 (Table 1). Du- sence of a large continuous area of presence ring the same periods, the total cumulative in the French Alps, despite the more than 20- area increased from 1,215 km2to 3,636 km?. year presence of individuals, remains unclear. This expansion was partly due to the greater There may be two explanations: (i) the range number of lynx-experts available after the new is under-estimated (i.e. lynx are present but training sessions, which had been organised not detected) because of certain habitat char- in accordance with the Engelberg symposium’s acteristics which make the detection of field recommendations. Confirmed signs of lynx signs more difficult, or (ii) a large lynx pop- presence were obtained in all major forested ulation is actually absent. regions of the pr6-Alpes (Chablais, Gli& Our simple presence-absence methodology Status ofthe lynx in the French Alps 13 Table 2 - Number of data collected and number or years with signs of lynx presence in the main forest- ed areas of the northern French Alps. Region Number of Number of years (identification number: see map) records with records Chablais (1) 6 4 Chamonix valley (2) 4 3 GlikredAravis (3) 5 3 Salkve (4) 4 2 Bauges (5) 3 2 Haute Maurienne (6) 5 2 Basse Maurienne/Belledonne/Taillefer(7) 17 5 Chartreuse (8) 7 3 Vercors (9) 6 3 Diois/Beauchi?ne/Devoluy (1 0) 7 5 Brianqonnais (11) 5 2 with a network of more or less evenly dis- mated, the presence of a large lynx popula- tributed observers is a good way to collect tion in the Alps is still improbable. The last large files of data on extensive areas. It is ef- dead lynx was found in the Alps in 1990, con- ficient even in the absence of permanent snow trary to the Vosges and Jura where cases of cover (i.e. most part ofthe lynx range in France) mortality have been registered more constantly because we use several sources of informa- (Stahl and Vandel, 1999). From a biological tion. In the Jura, we observed that the pres- point of view, the irregular findings of lynx ence of every radio-tracked lynx was detect- signs in the major regions probably was not ed more than once a year by the LCEG mem- just related to a permanent immigration-ex- bers (ONCFS, unpublished data). In French tinction process. Immigration from the Jura alpine habitats, we believe that the “presence” remains hypothetical despite the proximity of of a lynx is much more difficult to prove than the southern part of the large Jura lynx range: in the Vosges and Jura, and we are never sure very few data have been collected in the near- that “no data” is equivalent to “no presence” est pre-alpine regions of Chartreuse and of lynx. The low detectability of lynx signs in Bauges. The same is true for the Chablais area, the French Alps was suspected in some places which borders Switzerland. Thus, we believe (e.g. Glibre/Aravais) where confirmed signs that in the past years, lynx have been perma- of presence were obtained after several years nently present in the French Alps, but in cer- of suspected presence. The frequent scaveng- tain limited locations, e.g. the GlibrelAravis ing of lynx killed livestock or wildlife carcass region, the Taillefer region and the by corvids, foxes, wild boars and more recently Diois/BeauchCne/Devoluy region.