Cranes in France
migration and wintering
2001 – 2002


Postnuptial migration 2001      Wintering   2001-2002        Prenuptial migration 2002
 

Following an exceptional season (2000-2001), a return to normal conditions was witnessed, notwithstanding a noticeable level of wintering, the highest recorded, excluding last year’s figures, which were due to exceptional conditions. The significance of the French Crane Network is building up and at present includes 53 groups, covering practically the entire country (list). This synthesis would not have been possible without the help of members and observers who supplied the necessary data. Thanks also to foreign contributors, particularly those from Spain and Germany who enabled us to quantify the huge nocturnal flights of cranes crossing France. Our sincere thanks to all concerned!
Postnuptial migration 2001
  The season began with the observation of two cranes on the Lindre Lake (department 57: Moselle) on June 27th, probably summer migrants and possibly one of the two cranes which were observed on the same site on July 24th.
A juvenile crane was spotted in the Saône valley (department 70: Haute Saône) on July 8th. The date would suggest that the bird was summering in the region, possibly one observed 2 months earlier, approximately 20 kms upstream. Three birds in flight were then spotted on the 12th in the department 27 (Eure): both date and place are particularly remarkable. Further data acquired during the month of July correspond to the summering cranes observed on relatively habitual sites: 5 on the Lachaussée Lake (department 55: Meuse), 3 near the Madine Lake (department 55: Meuse) on the 15th and 5 on the Der-Chantecoq Lake (Department 51: Marne) on the 25th.
 
  Only 3 spottings of migrating cranes were noted in August including one in an unexpected department: 11 in the Haute-Marne (52) on the 21st, 60 in the Ariège (09) on the 25th and 9 in the Seine-et-Marne (77) on the 30th. The birds observed in the Ariège (09) had crossed into Spain shortly afterwards but the objectives of the of the other flights remains a mystery: did the cranes “touch down” somewhere in France (and, if so, why were they not spotted) or did they fly directly to Spain? It is worth mentioning the regular “stop-over” of a solitary crane in the Haut-Rhin (68) on the 28th and an increase in numbers on the Lac du Der (51) from 6 birds on the 11th to 14 on the 31st. This year, at least 7 cranes have summered on this site.  
  Photo de Grues cendrées : Jean Pierre FormetSeptember was relatively calm with only 7 migratory flights (6 of which took place during the second half of the month: 15 in the Indre-et-Loire (37) on the 15th, 21 in the Moselle (57) on the 18th, 10 in the Allier (03) on the 21st, 40 in the Cher (18) on the 22nd, 50 in the Nièvre (58), 29 in the Haute-Vienne (87) on the 24th and 21 in the Marne (51) on the 27th. The future of these cranes remains as mysterious as that of their flight patterns in August. Worth noting: the appearance of a solitary crane in the Mayenne (53) on the 5th. The total number on the Lac du Der (51) ranged from 14 on the 1st to 13 on the 9th (a juvenile died from unknown causes) thence to 15 on the 22nd.  
  No noticeable increase in migration figures was observed during the first 10 days of October. However, it is worth noting the following: the 5th (130 cranes), the 6th (206 cranes), the 8th (497 cranes) and the 10th (236 cranes) when several hundred migrating cranes were observed during the morning above Saint-Jean-Pied-de-Port (64: Pyrenées-Atlantiques) flying towards Spain, possibly August-September migrations, ending in Aquitaine (or elsewhere) and unobserved, but extremely
difficult to assess for lack of additional data. The first daily wave began on the 12th (105 cranes). Throughout this period, the numbers on the Lac du Der (51: Marne) increased from 19 (7th) to 41 (11th) whereas on the Temple Lake (10: Aube) the first crane was observed on the 6th. Finally, 3 cranes were observed on the same day in the Meuse valley to the north of the department (55: Meuse).

These initial movements amounted to at least 1,710 cranes of which only about fifty concerned birds located on the sites. Consequently, more than 1,660 cranes must have already reached Spain by this time, although we have no information on the subject.
 

First limited wave (14.10.01 – 20.10.01)

During this period, migration intensified with daily flights varying in numbers. Cranes recorded in the Hessen region of south-west Germany on the 14th were located in the Marne (51) and the Ardennes (08) at the end of the same day, respectively at 17h30 and 18h30. By contrast, very few movements were recorded on the following day. Most of these birds were observed in the north-east as far as the Lac du Der (51) where 417 were counted in the “dormitory” area on the morning of the 16th and no doubt on the other sites in the Lorraine region about which we have no information. On the same day (16th) several hundred birds crossed France, some crossing the Pyrenees in the evening. The first flights extended throughout the night of the 16th to Organbidexka (64).The following three days (from the 17th to the 19th) significant numbers of cranes arrived and crossed over: every day some 2,OOO to 2,700 birds crossed France following the usual flight corridor. The majority landed on the large lakes in the Champagne region: 2,400 cranes on the Der Lake (51/52) on the morning of the 18th, followed by 4,000 more on the 19th in the evening; 450 birds arrived on Temple Lake (10) in the evening of the 17th and 704 during the morning of the 20th. Some sites in the south-west were also filling up: 25 cranes in Puydarrieux (65) on the 17th (but only 3 the following day) and 254 in Arjuzanx (40) during the evening if the 18th. It is also worth noting that 103 birds spent the night of the 18th in the Teich Park (33) and left at 10 o’clock the following morning.

In all this wave comprised at least 8,120 cranes.

First large wave (20.10.01 – 21.10.01)

During the previous movements, one large wave arrived in a short space of time on the 20th. Close on 12,000 birds were observed in the Hessen region. The first migrants were seen in France at 5 p.m (5 in the Vosges (88) and at 6.30 p.m (15 in the Marne (51) but the majority of birds arrived during the night of the 21st. Almost all these cranes stop over on the sites in the north-east, particularly in Champagne on the Der Lake (51/52) where the majority of birds gather: 9,690 during the evening of the 20th and 15,610 on the morning of the 23rd. Two hundred birds arrived on the Lachaussée pond (55) in the Lorraine region during the morning of the 21st, whereas only one crane was visible the previous evening. Finally, in the Aube (10), there were 2,614 cranes on the Temple Lake on the 27th in the morning, almost certainly part of the wave comprising at least 13,840 cranes.  

Departures from champagne and second small wave
(22.10.01 – 03.11.01)
 

 

During this period, the majority of movements involved birds leaving Champagne (at least 19,640) by means of the usual migration route (see map n°1). The main observation dates for this phenomenon were provided by data recorded in the Nièvre (58): 2,100 birds on the 28th, 8,650 the following day, 3,750 on November 1st and 1,400 on the 2nd. However, arrivals were evidently taking place in Champagne throughout this 13-day period, since the numbers on the large lakes had not varied to such a degree. Numbers on the Der Lake (51/52) fell from more than 12,430 birds on the morning of October 28th to 2,580 on the 3rd November (morning). The same tendency was noted on the Temple Lake (10), numbers falling from 2,614 birds on October 27th (morning) to 160 on the 31st (evening) and only 18 the following evening. The arrivals were confirmed by the increase in numbers counted in the Lorraine region: 3 birds on the Videlange pond (57) on October 27th, 375 birds on the Lachaussée pond on October 29th, then 500 on November 2nd. Finally, 19 cranes were spotted on the Lindre pond (57) on November 1st.  

Map 1 : Total number of Common cranes during the first wave
between the 20st October and the 3th November 2001

 

 

 

 

 

In addition, the numerous movements recorded on the usual migration path, resulted in arrivals of birds on sites in the west and south-west. The Baie de l’Aiguillon (85) was visited by the first two cranes on October 27th and the number increased to 10 on November 3rd. In Aquitaine, 457 cranes were observed in Arjuzanx (40) on October 30th in the evening: the same day 6 were counted in Captieux (33/40) and 107 the following morning. Six cranes were seen in the Park du Teich (33) also on the 30th and the number rose to 24 on the following day. Finally the numbers increased from 6 birds on the Puydarrieux Lake (65) on October 22nd to 13 on November 3rd. the importance of these movements is born out by the counts carried out by the OCL located on the 3 mountain passes in the Basque country (64). More than 11,000 cranes were thus observed crossing the Pyrenees between October 18th and November 4th with several peak days as, for instance, the 29th (3,286 cranes), the 30th (1,584) and the 2nd November (1,155).

In all, the additional arrivals recorded during the 13-day period amounted to at least 8,300 birds.

Second large wave (04.11.01 – 08.11.01)

 

From the evening of November 4th, regular and relatively large numbers of cranes arrived in France, often crossing without stopping in Champagne. The birds’ flight path was very much to the east of the country due to a strong west-southwesterly wind (please see map n°2). The main migration dates were between the 5th and 7th November with a maximum number of birds on the 6th (5,650), many crossing into Spain via the Pyrenees in the Haute Garonne. The same strong wind forced the birds to fly slowly and those recorded in south-west Germany during the day, crossed France throughout the night and the following day. However, during the 5-day period, more than half the cranes stopped over on sites in north-east France. One hundred birds were recorded on the Lindre pond (57) on November 6th and 1,200 on Madine Lake (55) on the 7th. Numbers on the Der Lake (51/52) were estimated at over 10,000 on the morning of the 9th and there were 170 birds on the Temple Lake (10) on the 7th, in the evening. In addition, small groups of migrants were occasionally forced to stop over in unfamiliar places, as for example, 180 birds in the Bas-Rhin (67) on two sites, in the south-east of Haute-Marne (52) 71 birds and the Loire (42) where 175 cranes occupied 3 sectors. Part of the birds crossing France stopped over on sites in the south-west. 960 cranes were also recorded in Arjuzanx (40) on the 7th in the evening. The numbers recorded in Puydarrieux (65) increased from 14 on the 4th to 85 on the 6th, decreasing to 14 on the 8th and finally amounting to 87 on the morning of the 9th.

The total amount of birds recorded during this second large wave was at least 16,960.
 

Map 2 : Total number of Common cranes during the wave
between the 4st and the 8th November 2001

 

Third large wave (09.11.01 – 16.11.01)

Following a sharp decrease in temperature on November 9th, many cranes left their sites in north-eastern France, principally on the Der Lake (51/52): at least 4,500 birds were seen in the Nièvre (58) during the afternoon; at the same time, a substantial departure from Germany was recorded (at least 96,000 birds): 33,000 were seen flying towards the south-west of Hessen in the afternoon. Driven by a strong north-easterly wind, the cranes rapidly crossed our country during the night of November 9th using the usual flight path (please see map n°3). More than 15,000 of them succeeded in crossing the Pyrenees, arriving in Gallocanta on November 10th. The data recorded in the Nièvre is the only source of information available which gives us some idea of this impressive wave: an estimated 11,300 birds during the night of November 9th between 9.30 p.m and 01.30 a.m. Despite this, many birds stopped over in France. There were at least 17,000 cranes on the Der Lake (51/52) on November 10th (morning) and 3,945 in Arjuzanx (40) in the evening. On the same day, many birds left the Der in the morning and at least 6,340 were recorded in the Allier (03) during the afternoon.
Photo de Grues cendrées : Jean Pierre FormetDuring this period, at least 9,120 cranes also left Germany (6,120 from Hessen) and similar to the day before, crossed France during the night and following morning (11th). That day, the numbers recorded on certain sites provided some idea of the movements: 11,890 birds on the Der Lake (51/52) in the morning, 1,200-1,600 on the Temple Lake (10) in the morning, 941 on the Craon Pond (18), 550 in the Captieux (33/40) and 4,491 in Arjuzanx (40) in the evening. Some birds (at least 950 were seen during the afternoon in the Nièvre (58)) left the north-eastern sites immediately. During these last two days, more than 4,400 cranes were recorded by the OCL on migration routes over the Basque mountains. Also on the 11th, a further 3,000 birds left Germany and were seen flying over Hessen, but very few were recorded in France. However 18,421 cranes were counted on Arjuzanx (40) on the 12th in the evening, pointing to the arrival of this wave and clearly the movement of birds from central France. Similarly, other cranes, not observed in Hessen, probably arrived during the night, according to a count carried on the Der during the morning of the 15th (please see below. 58 birds were also seen in the Baie de l’Aiguillon (85) on the 12th. During this period, the numbers of birds in Puydarrieux (65) remained fairly stable, fluctuating between 61 and 87.
 
On November 13th, fresh departures from Germany were recorded, 3,000 birds from Hessen, but a number of other birds probably went unnoticed, since on the morning of November 15th, 20,884 birds were counted (the season’s record) leaving the Der Lake (51/52) where many, but not all the birds had been forced to stop, since 1,400 which were counted in the Nièvre during the morning and beginning of the afternoon must be included in these movements. This inflow of birds also increased in numbers at the Puydarrieux (65) site where the total amount rose from 64 in the morning to 217 in the evening of the 14th. On the same day, 470 additional birds were recorded in Hessen, for the most part, crossing France in the night and during the morning of the 15th . New arrivals were recorded in the south-west, for example in Puydarrieux (65) where numbers rose from 251 in the morning to 328 on the same evening. The intense migratory wave ended on November 16th when only approximately 20 birds were seen in the Gironde (33). The numbers on the Puydarrieux site peaked at 362 in the morning, decreasing to 227 in the evening. In the Baie de l’Aiguillon (85), several birds also arrived, since 67 were recorded on the same day.

This third, largest seasonal wave comprised a total of at least 57,740 cranes over a period of 8 days, 9,000 more than numbers recorded before November 9th. Many more, flying during the night, went unrecorded.
 

Map 3 : Total number of Common cranes during the wave between
the 9st and the 16th November 2001.

 

Irregular movements (17.11.01 – 12.01.02)

From November 17th, migration decreased sharply, and movements became extremely irregular. Arrivals from Germany, although on a daily basis, apparently involved very few birds. The main data resulted from a period commencing on December 5th and ending on the 12th. In fact, despite the cold weather which set in from mid-December, few migrants were observed in the usual flight channels since it would appear that many birds, having left Germany and the Lorraine, had come to the Der (51/52). Numbers on this site decreased progressively, from more than 20,000 birds in mid-November (please see previous paragraph) to 15,930 on Decembre 12th then decreasing to 16,060 on the 13th and more than 19,000 in mid-January  (please see paragraph on wintering), a phenomenon never previously witnessed!

However, many cranes must have passed unnoticed (but in what proportion?). The record number observed was on the evening of November 19th with 29,423 birds following the end of the previous large wave. On the following evening, the site was host to only 8,965 birds, the remainder having no doubt moved on to Spain. The numbers then fluctuated considerably between 8,289 (December 29th) and 16,586 (November 28th) a variation in numbers of some 3,000 birds frequently observed every 3 or 4 days. This phenomenon is difficult to explain in the absence of additional data, particularly since numbers at Captieux (33/40) are relatively stable, however with an increase in mid-December and another at the beginning of January: 3,690 on November 21st, 3,100 (30th), 3,650 (December 10th), 4,212 (20th), 4,190 (30th) and 4,800 in mid-January. Numbers decreased in Puydarrieux (65) from 300 cranes on November 18th in the morning to 120 in the evening, followed by fluctuations (between 124 and 162 birds) recorded between November 18th and December 12th.

Several arrivals were observed on December 13th (179 in the morning and 164 in the evening) and on December 18th (178 cranes). The numbers then stabilised until mid-January when fluctuations occurred once again. On the whole, the increase in numbers was very noticeable on the majority of sites between the beginning of December and the beginning of January. In the Baie de l’Aiguillon (85), there were 80 birds on November 21st and 109 on January 5th. On the Cousseau Reserve (33) 20 cranes were recorded on November 21st, 23 on the 27th, 50 on December 11th and 86 on January 8th. Elsewhere, small groups of birds gathered for varying periods of time on more uncommon sites which bore witness to the movements recorded at the end of the year: the Bas-Rhin (67) on November 17th, the Cher (18) on the 18th (120 birds), the Haut-Rhin (68) on the 21st, the Haute-Sâone (70) on the 22nd (4 birds until December 1st), the Oise (60) on the 28th, the Nièvre (58) on December 9th, the Yonne (89), the Cher (18) and the Pyrénéés-Orientales (66) on December 10th, the Aude (11) on the 14th, the Haute-Vienne (87) on the 15th, the Ille et Vilaine (36) and the Aude (11) on the 16th. As regards the Lorraine, we possess very scant data. Several hundred birds were recorded during this period with a maximum 184 cranes on the Lindre pond (57) on December 2nd. The last two birds were observed in Woëvre (55) on the 21st. Minor movements were recorded in January, principally between the 2nd and the 7th, and involved birds located in the north-east and fleeing fron the harsh weather conditions. The last flight towards the south-west (6 cranes) was recorded in the Aude on the 12th.

In all, the movements recorded during the two months, involved more than 9,740 cranes. This is a modest assessment, since the movements recorded at Arjuzanx (40) probably involve a far greater number of birds, but confirmation of this hypothesis is impossible through lack of data.

 
  The total number of birds recorded during the 2001 post-nuptial migration amounts to approximately 116,400 cranes which is far below the real figure since this represents no more than 4/5 of the estimated population of migrants using the west European route. The logical explanation is the considerable underestimation of large waves of migrants participating in nocturn flights.  

Postnuptial migration 2001      Wintering   2001-2002        Prenuptial migration 2002
 

Summary

 

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