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Postnuptial migration |
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Apart from the Common Cranes on the nesting sites in the Lorraine, a group
of 13 birds was also observed in the Nièvre department (58) at the end of
June, probably summer visitors. The following observation was made on the
Der lake (51/52) on July 21st where 3 birds were noted. One Common Crane was
seen on the Lavours marshes Natural Reserve (01/73) on August 5th. The first
small migratory group was observed in the Loir-et-Cher (41) flying over
Saint-Romain-sur-Cher on August 22th. A second group was observed in the
Vendée (85) towards the end of the evening on August 31th. Numbers regularly
increased on the Der lake (51/52) and amounted to 22 birds on August 24th.
Approximately, 20 cranes where seen in the Orne (61) on September 5th. A
larger group was counted on September 7th in the Nièvre (58) amounting to
150 birds. Once again, these were certainly seasonal individuals. Few
movements were noted during September : only 5 departments were concerned :
the Nord (59), the Val-de-Marne (94), the Indre (36), the Haute-Marne (52)
and the Nièvre (58). Between October 1st and 8th, several small flights were
observed every day, totalling 180 birds, throughout 9 departments. For
example, 32 cranes in the Bas-Rhin (67) on October 1st and 20 birds in the
Loire (42) on October 5th. These flights made up the advance guard for the
main autumnal migratory wave in 2004 and involved at least 600 birds.
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First wave
(09.10.04 – 13.10.04)
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Commencing on October 9th, several hundred Common Cranes left the Rügen
region in Germany, flying towards France. From 16h00, the birds arrived in
the Meuse (55) and in Champagne. Octobre 10th was no doubt the date on which
the main migration commenced : ever-increasing numbers arrived during the
day. More than 25,000 birds was counted in the Hesse region in Germany. The
following day, the movement intensified: 7,000 in the Haute-Marne (52), 1
400 in the Côte d’Or (21) and 1 900 in the Nièvre (58). On the morning of
October 12th, more than 39,000 cranes landed on the Der lake (51/52), thus
establishing a new record and contrasting sharply with the 200 cranes on the
lake two days previously. Two other sites attracted the birds: the Madine
lake (55) with 200 cranes and the Landes pond (23) with 2,000 birds on the
following day. On the same day, flights were observed further south, such as
in the Cher (18), the Saône-et-Loire (71), the Allier (03), the Loire (42),
the Dordogne (24) and the Hautes-Pyrénées (65). On October 13th, 6 cranes
were seen in the Alpes-Maritimes (06) and 6 in the Sarthe (72). This wave
was on an extremely large scale as can be demonstrated by the numbers on the
Der lake (51/52) on October 14th, amounting to more than 66,500 cranes.
Furthermore, 2,300 landed on the Temple lake (10), 300 on the Lachaussée
pond (55), 519 in Arjuzanx (40) and 21 in Puydarrieux (65).
During these 5 days, at least 73,000 Common Cranes arrived in France.
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Map 1 : Total number of Common Cranes counted between
October 9 th and November 13th 2004.
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A quieter period interspersed by
several significant days of migration (14.10.04 – 03.11.04) |
During this period, movements were more difficult to quantify: several
days when numbers were low, punctuated by brief, intense peaks when numbers
were extremely high. On October 15th, 150 cranes migrated to the Sarthe
(72). On the 16th, 2 arrived in the Haute-Savoie (74). During this period, 1
bird was seen in the Manche (50). On October 22th , birds were seen
leaving Champagne. More than 10,000 cranes flew over the Nièvre (58). On the
same day, the first bird arrived in Cousseau (33) and in the evening, 86
arrived in Puydarrieux (65). On October 24th, 4,200 cranes were observed in
the Nièvre (58). Another outstanding day for migration was October 26th
: 21,000 birds flew over the Nièvre (58) then theAllier (03) and the
Creuse (23). The following day, a further 4,000 cranes left the Champagne
wetlands and 1,350 flew over the Vienne (86). On October 28th, 9,800 birds
migrated to the Charente (16), 19,275 crossing over the Pyrenees were
observed by the O.C.L. and 63 arrived in the Aiguillon bay (44). On the same
day, 1,855 birds arrived on the Horre pond (52/10). Migration continued over
the Pyrenees with 16,000 birds on October 29th. Cranes were also observed
flying over the Oise (60) and the Val-de-Marne (94). On October 31st, more
than 6,000 birds crossed over France. On November 1st, 1,000 cranes were
counted on the Lachaussée site (55) and the same number was seen on the
Forêt d’Orient lakes (10). During the same period, 330 birds were observed
on the Captieux site (33/40). The following day, the count was higher in the
Aquitaine region, 700 in Captieux (33/40) and 3,900 in Arjuzanx (40).
250 cranes were counted flying over the Territoire de Belfort (90), 650 in
the Charente (16) and 92 on the Puydarrieux lake (65). On November 3rd,
2,240 cranes were counted on the Forêt d’Orient lakes staging point (10).
This wave amounted to appoximately 21,000 birds.
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Map 2 : Total number of Common Cranes counted between
October 14th and November 3rd 2004.
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Second wave
(04.11.04 – 14.11.04)
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On November 4th, 2,100 cranes flew over the Vienne (86),
assisted by favourable weather conditions during the night of November
4th-5th. Calm and sunny weather prevailing over France on November 5th
encouraged the cranes to continue migration: more than 51,000 birds flew
over the country on this day alone. Substantial flights were observed over 9
departments, between 20,000 and 45,000 in Burgundy and in Central France.
More than 50,000 in the Allier (03). Flights arrived after nightfall in the
south-west. Consequently, estimations were impossible. However, the number
and length of flights confirm the extent of the migration. During the night
of November 5th-6th, large flights crossed over the Pyrénées-Atlantiques
passes (64) into Spain. On November 7th, 2 flights of respectively 15 and 18
cranes were observed in the Alpes-Maritimes (06) and the Haute-Corse (2B).
Other large flights were seen over the Nièvre (58) with 7,000 birds,
reaching the Allier (03). On November 8th, 4 cranes were spotted in the
Bouches-du-Rhône (13) and a flight in the Pyrénées-Orientales (66). On
November 9th, a further 28 birds migrated to the Pyrénées-Orientales (66).
Flights were also observed in the Lot (46), the Tarn-et-Garonne (82) and the
Gers (32), some of which included a large number of birds. Flights
throughout Central France were also impressive: 18,000 birds in the Nièvre
(58) as well as in the Cher (18), 15,000 in the Creuse (23) and 36,000 in
the Allier (03). Towards the end of the wave, about 3,000 cranes arrived in
Captieux (33/40) and more than 9,000 in Arjuzanx (40). On November 13th, 80
birds were counted on the Montbel lake in the Ariège (09). On November 14th,
1,520 cranes were counted on the Puydarrieux site (65), while 650 were
spread over the three main sites in Central France. On November 15th, only
14,500 birds remained on the Der lake (51/52).
The main autumnal wave included at least 100,000 Common Cranes counted over
12 days.
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Map 3 : Total number of Common Cranes counted between
November 4th and 14th 2004
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A quieter period
(15.11.04 – 19.12.04)
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Migration over France declined between mid-November and
mid-December. Data was provided by 26 departments, but numbers were low.
However, one date was remarkable for above-average numbers : December 14th
when 1,700 birds were counted in the Cher (18) and 2,000 in the Nièvre (58).
As far as the rest of this period is concerned, some of the highest numbers
recorded are: 700 in the Marne (51) on November 30th, 660 in the Vienne (86)
on the same day, 875 in the Haute-Vienne (87) on December 1st and 540 in the
Charente (16). It is worth noting that 14,250 cranes were observed on the
Arjuzanx site (40) on December 14th.
In all, 13,000 birds migrated during this month. |
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The end of migration
(20.12.04 – 27.12.04)
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The cold weather set in over France and a number of cranes continued their
migration towards the south-west. Consequently, on December 20th, close on
6,000 birds were observed in the Nièvre (58). Others were seen in the
Limousin region : well on 2,000 cranes in the Haute-Vienne (87) and in the
Auvergne region : 600 in the Allier (03). On December 22th, 30 cranes
migrated to the Saône-et-Loire (71). The following day, 55 birds were
observed in the Territoire de Belfort (90) and on the 26th, more than 1200
left France via the Pyrenees. To all intents and purposes, December 27th was
the final day for postnuptial migration, flights coming to an end in the
Hesse region in Germany. These last flights involved about 2,200 birds. |
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2004 postnuptial migration
overview |
In all, at least 210,000 Common Cranes
took part in the migration or « stopped over » in France. This was an
all-out record surpassing by far estimated numbers for the previous year
(160,000-180,000 birds). The regular growth in numbers in Western Europe
cannot be the sole reason for this increase two years running. Could this
phenomenon be partly connected with numbers of birds flying over Central
Europe via the west-european route? Other reasons may also be due to
variations in bird counts. For instance, this autumn, there were fewer
nocturnal flights across France than in previous years : large numbers of
cranes landed on the Der lake, if only for a few hours, before leaving
during the morning. Constant progress in the observation network is also an
important factor.
This overview has been compiled with the help of counts carried out on
German sites.
For example, on October 21st 2004, about 160,000 cranes were counted there,
whereas more than 173,000 had already arrived in France (cf. supra).
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2004 :Postnuptial migration
Wintering : 2004/2005
Prenuptial migration 2005 |
