COMMON CRANE IN FRANCE

Migration and wintering – season 2000/2001

 

This annual synthesis, particularly rich, is set out on three pages
Post-nuptial Migration 2000     Wintering 2000-2001      Pre-nuptial migration 2001

The long trip of migratory birds is surely one of the most fascinating spectacle that Nature can offer. The migration of common cranes does not go unnoticed : their typical trumpet-like calls which go all over our country, their impressive V flights which glide over Men's heads… These moments remain magic and rhythm Men's activity.

Many ornithologists had wished for several years to group each other in order to follow cranes migration across our country. They have founded the French Crane Network which today groups about 50 organisms.

Each year, a synthesis of the observations done of the preceding season is done. This present document will make you discover the details of common cranes migration during the season 2000/2001. This migration was exceptional in our country since about 80,000 cranes were grouped at the same time at the Lac du Der-Chantecoq in November. This concentration made that this stage-site was punctually the most important one in Europe for migratory cranes.

 

Post-nuptial migration – 2000

 

The first birds : July 12

to October 14

A few birds are noticed in summer in several places, mainly in Champagne-Ardenne and Lorraine. However one immature crane stays at Termignon (73) from July 12 to August 15 ! The first flight of migrating cranes is heard at night on August 11 over Montluçon (03). Only 4 flights are noticed in August. September is quiet too : only 11 days provide us with data of migrating cranes. However we must not forget the 24 with about 370 cranes noticed in migration in Haute-Vienne. That same day, 44 individuals are present at the Lac du Der-Chantecoq. Migration remains quiet during the first two weeks of October : the most interesting day is the 13 with only 122 cranes noticed in 2 flights. The day after, there are 113 cranes at the Lac du Der-Chantecoq. Those first movements represent a total of at least 1,520 individuals.

The first little wave

October 14 to 17

This wave starts at the end of the afternoon of the 14 with flights noticed in Ardennes and in Loiret. On the 15, many cranes are seen in migration, mainly in the North-east regions (Champagne-Ardenne, Lorraine and Alsace) but also in the West ones (Mayenne, Loire-Atlantique). However, a little number of birds are counted compared to the size of the (nightly) movement : we can explain this because many cranes stop on the big lakes in Champagne, more especially at the Lac du Der-Chantecoq where 4,960 individuals leave the dormitory-site on the morning of the 17. An important part of these birds (more than 1,400) leaves the lake during the morning and is noticed at the end of the afternoon in Nièvre, Allier and Limousin. This first wave represents a total of at least 6,740 common cranes.

A second little wave

October 18 to 20

Just following the preceding wave, a new movement happens during those 3 days. Mainly localised in Champagne Humide, this movement is not really noticed elsewhere, and an important part of those cranes stop at the Lac du Der-Chantecoq (almost 7,000). The 18, 982 cranes pass the Pyreneans by the Basque passes studied by OCL. Those cranes are probably the ones which have left Champagne the day before. The 20, a number of 10,110 individuals is counted leaving the resting place of the Lac du Der-Chantecoq. The total number of this wave is at least of 7,420 common cranes.

The first big wave

October 21 to 24

Just after the preceding movements, this wave mainly happens on October 22 and 23. Many birds are noticed along their usual migratory lane during those two days. An important part of those cranes stop on the big lakes in Champagne (about 9,000) and the flights noticed elsewhere in France are not very big (see map 1). In the morning of the 25, there are 15,320 individuals at the Lac du Der-Chantecoq. Some 1,600 cranes cross the Pyreneans towards Spain during those days, more especially on the 23 when the members of OCL count about 1,200 birds on their 3 sites of study. The total number of this wave is at least of 11,500 individuals.

Map 1 : Total number of Common cranes during the first wave between the 21st
and the 24th October 2000

A third little wave

October 25 to November 3

From October 25 to November 3, migration seems to slow down. The flights seen along the migratory lane mainly concern small leavings from Champagne. However, many cranes do reach France since we count 21,590 individuals on October 29 leaving the dormitory-site at the Lac du Der-Chantecoq (that is to say 6,000 more birds than 4 days before). It is probably more than 8,000 cranes which thus reach France. This wave represent a total of at least 9,570 common cranes.

An exceptional November

November 4 to 26

A very important movement of common cranes coming from the North-east occurs after November 4. However, because of the meteorological conditions of the moment (rain and very strong wind from the West), the waves of cranes leaving Germany are often forced to stop in the South-west of that country, in Belgium, in Ardennes and in the North part of Lorraine. An important part of these cranes will then progressively join those already grouped at the Lac du Der-Chantecoq. Those birds are noticed in an important number of departments even if the usual migratory lane remains dominating (see map 2). But in reality, the cranes noticed along this lane are mainly birds which have left the big lakes of Champagne (mainly the Der).

But let's go back to the beginning of November. The 5 is an important day with at least 8,900 individuals leaving the big lakes : these birds are mainly noticed in Aube and Yonne. That very day and for the second consecutive year, 7 cranes are seen in Corsica (West coast). From November 7 to 9, little groups of cranes stop in many places to have rest, especially in the North, in Belgium, in Luxembourg and in South-west Germany.

On the 8, there are 20,400 cranes on the Lac du Der. Then they are 31,660 on the 10 and 46,520 on the 13 : the site's record is beaten! The number of cranes on this site increases tremendously if we consider the figures at the beginning of the season. Thus, we count 72,760 cranes in the morning of the 26 ! Moreover, more than 10,000 cranes have left the lake the day before, so there must have been more than 80,000 birds at the resting place. These birds do not travel far away since most of them finally join the dormitory sites of the lakes of Aube. At the same time, the number of cranes at the Aquitaine sites are very low. On the 17, we thus count 1,800 cranes at Captieux and less than 600 at Arjuzanx. There are 2,185 individuals on this last site on the 25.

This incredible movement represents a total number of at least 86,100 common cranes including 80,000 which have stopped on the lakes of Champagne-Ardenne.

Map 2 : Total number of Common cranes during the big wave between the 4st
and the 26th November

Massive leavings of Champagne

November 27 – December 12

Meteorological conditions change after November 27 and enable a progressive leaving of the cranes which were staying in Champagne. The movements are less impressive than what we could expect. Thus, on the Lac du Der, the number of cranes decreases to 34,350 individuals on December 3, and to 23,360 on the 17. On November 27, at least 31,000 leave the Lac du Der but most of them join the Lacs de la Forêt d'Orient. On the 28, 22,880 common cranes leave the resting places of those lakes and thus obviously beat the record of the site. That very day, 9,000 cranes leave Champagne. On the 29, 6,450 individuals are noticed at Captieux and 4,190 at Arjuzanx. Another leaving of Champagne is noticed on December 4 with more than 8,000 birds seen mainly in Yonne and Cher. In the morning of the day after, 11,840 cranes are counted at Arjuzanx. On the 18, there are only 3,610 cranes left on the Lacs de la Forêt d'Orient.

In parallel to those leavings, a few birds coming from Germany still fly across France. Those 23 days nevertheless represent an added number of at least 3,860 common cranes.

Another big wave

December 20 to 24

During these 5 days, an important movement leaves Germany and reaches France because of the first cold temperatures of the season… Even if the migration is noticed along the usual migratory lane, the flights are seen more in the West. This is due to the winds coming from the East which are noticed during that period (see map 3). We thus count a record of about 5,000 cranes in Charente-Maritime ! Many of these cranes stop at the Lac du Der and often leave the day after towards the South-west. This movement represents a total number of at least 12,790 common cranes, which had never been noticed in that period of the year ! The number of cranes stopped in Aquitaine then increases from 16,000 to 31,000. There are still 28,000 cranes at the Lac du Der on the 23.

Map 3 : Total number of Common cranes during the wave between the 20st
and the 24th December 2000

End of the movements and pre-wintering

December 26 – January 11

A few flights are noticed during that period and mark the end of the arrivals from Germany. This concerns at least 560 common cranes, mainly on the 30 after the arrival of cold temperatures and the fall of snow. Some flights can also correspond to movements of local birds. There are still 26,600 individuals on the Lac du Der on December 30.

The last movements

January 12 to 17

After the main cold wave of that winter, a new leaving of the North-east birds happens : those birds mainly leave Champagne though they wanted to spend winter on the sites of that region. Simultaneously, about 500 cranes arrive from Germany ! On the 13, for instance, about 8,000 individuals which had stopped on the big lakes of Champagne-Ardenne fly towards the South-west, and again on the 14 with 2,000 cranes coming from the Lac du Der.

If we add the different waves that we have studied, we find a total number of 140,500 cranes which have stopped in France or simply crossed the country. This number is very big and is probably (strongly ?) over-estimated. We must not forget that the exceptional movements in November have not made our study easy and accurate.

Migration post-nuptiale 2000     Wintering 2000-2001       Pre-nuptial migration 2001

Summary

 

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