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The summer was very changeable, after an early spell of good weather in May, heavy rains and cold weather periods were not ideal for a species, whose main summer food for its young is wasp grubs. Between us, we located three nests, but two failed probably at the small young stage. This year we were eager to place a transmitters on adult birds and find out if experienced birds migrated towards the short sea crossing between England and France, rather than risk the more westerly routes through the western parts of the United Kingdom or even into Ireland. We decided to try to catch one of the adults at the main nest site. On 5th August, we caught the adult male (pictured below) who is a most distinctive and very pale individual.
He was ringed GF 53481. The measurements were: wing length 410 mms, tail 253 mms and weight 785 grams. He was in excellent condition. We fitted one of the new generation satellite transmitters (number 21253) which use the new Argos 2 satellite system and a manufacturer's refinement called SiV (Satellite in View). This should give more accurate signals during migration. On release he flew off strongly and joined the female who had been flying over head (she is a dark brown individual). Six day interval signals during August were received from the general region of the nest site and on one day Brian Etheridge saw him hunting about 4 kilometres from the nest. His migration
started on 5th September and we will now paste up his active migration map
and the key dates and places ofhis migration. As last year, the exact nest
site in a Forestry Commission forest is confidential and the starting
coordinates are 57.483N 04.166W, which is the site of the Forestry
Commission headquarters in Inverness. |
DATE | LATITUDE | LONGITUDE | LOCALITY |
05/09/02 | 57.483N | 04.166W | Inverness at nest |
05/09/02 | 56.508N | 3.112W | Nr Dundee, Angus |
06/09/02 | 55.501N | 2.260W | Nr Yetholm, Borders |
08/09/02 | 54.878N | 2.099W | Riding Mill |
08/09/02 | 54.080N | 1.644W | Nr Harrogate |
10/09/02 | 53.670N | 1.119W | Near Snaith |
10/09/02 | 51.865N | 1.405W | 12 kms N of Oxford |
12/09/02 | 48.375N | 1.056W | E of Fougeres, France |
12/09/02 | 46.114N | 0.933W | E La Rochelle, France |
14/09/02 | 43.748N | 1.297W | W of Dax, SW France |
14/09/02 | 42.286N | 2.190W | Ausejo, Spain |
16/09/02 | 39.768N | 2.376W | Altarejos, Cuenca |
18/09/02 | 38.054N | 2.805W | Sierra de Segurra, |
18/09/02 | 37.225N | 3.750W | just W of Granada |
20&22/09/02 | 33.383N | 5.906W | NW Khenifra,Morocco |
24/09/02 | 30.900N | 5.900W | Ait Silo, Morocco |
24/09/02 | 28.574N | 6.518W | Khorb el Ethel, Algeria |
26/09/02 | 25.266N | 3.640W | Just N of Mali/Algeria |
28/09/02 | 17.674N | 8.260W | Outfene,S Mauritania |
28/09/02 | 14.407N | 9.246W | Moutan Kagoro, Mali |
30/09/02 | 11.483N | 6.526W | Ouola, Mali |
2/10/02 | 10.228N | 4.050W | Ouo, S Burkino Faso |
2/10/02 | 8.942N | 1.228W | New Tamale,Ghana |
4/10/02 | 8.737N | 0.199E | near Agofie, Ghana |
4/10/02 | 9.318N | 0.773E | Near Bassar, Togo |
6/10/02 | 9.803N | 3.100E | Near Nikki, Benin |
8/10/02 | 9.623N | 3.942E | Nr Kaiama, Nigeria |
10-20/10/02 | 9.095N | 7.003E | Abuja, Nigeria |
20/10/02 | 7.327N | 7.485E | Okua, Nigeria |
22/10/02 | 5.019N | 8.994E | Cameroon border |
24/10/02 | 3.004N | 10.182E | Kribi, Cameroon |
26/10/02 | 1.707N | 9.333E | Bata, Guinea |
28/10/02 | 1.008S | 9.301E | Ogooue Maritime, Gabon |
12/11/02 -12/03/03 | 1.128S | 9.252E | Ogooue Maritime, Gabon |
Comments
The male bird was still around the nest area at 1108 am on 5th September; by which time its young had been flying for nearly two weeks. By 1922 pm it had flown 140 kilometres to the south-east and was, presumably roosting in woodland, about 5 kilometres north-west of the city of Dundee. Next day, it crossed the Tay estuary and the Firth of Forth on a similar heading and reached the Scottish Borders, near Yetholm, by 1856 pm. This was a further daily flight of 115 kilometres.
There were no expected signals from the transmitter on the 7th September. On the 8th, it was near Riding Mill, west of Newcastle at 0957 am and by 1948 it had reached an area about 10 kilometres north of Harrogate, where it roosted overnight. The male has covered 435 kilometres in 4 days and is at present heading to the east of south towards a possible short sea crossing into France.
No signals expected on 9th, which was a day of heavy rain in England. On 10th, a poor quality signal was received from near Snaith, north of Doncaster, at 1056am. By 1903 pm the male was 12 kilometres NNW of Oxford, having covered at least 210 kilometres during the day.
No signals expected on 11th, which was disappointing as the bird must have crossed the English Channel that day. It is most likely to have flown out from the Isle of Wight to the Cherbourg peninsula. Today 12th September, received two rather poor definition signals. The first was at 1004 am and was near Fougeres, north east of Rennes. Ten hours later, after dark, the male was east of La Rochelle, possibly roosting in the Foret de Benon. It travelled at least 250 kilometres during the day and the journey distance since leaving its nests is now about 1300 kilometres. Today's heading suggested the bird is heading for the western end of the Pyrenees. Its direct journey through the UK and into France is a clear sign of an experienced adult travelling a well known journey (in contrast to last year's youngsters).
The first signal at 0921
local time 14 September was west of Dax with the male travelling over the
forests of the Landes; he was clearly heading for the western end of the
Pyrenees. The next signal (10 hours later) was very accurate (to within
150 metres accuracy) and was near Ausejo, 25 kilometres ESE of Logrono in La
Rioja, Spain. He had travelled 190 kilometres.
Once he had crossed the
Pyrenees he appears to be heading directly for the Straits of Gibraltar.
While we have enjoyed summer like weather in Scotland, low pressure off Portugal brought rain and strong winds to Spain. In consequence, the male honey buzzard had only travelled 260 kilometres in two days, keeping to a southerly route - east of Madrid. The lack of good signals also suggested he was low down roosting in woodland some of the time.
In the morning of the 18th September, the male was along the west side of the Sierra de Segurra and probably by now in company with other honey buzzards heading towards Africa. About 120 kms had been covered by evening and the bird had now changed direction to the SW and on towards the Straits of Gibraltar.
We did not expect a signal
on 19th September. By the evening of the 20th, the bird had travelled to an area
NW of Khenifra in Morocco. This was in the middle Atlas mountains and about 350
kilometres south of the Straits of Gibraltar. It is not known if our male
travelled through Gibraltar or went straight across the sea. I emailed John
Cortes (Gibraltar Ornithological and Natural History Society) and he replied
that on the 19th and 20th the conditions at the Rock were calm and only small
numbers of honey buzzards were seen. He thought they could be
crossing to the west from Spain or even taking the longer
eastern
passage over the sea. He also added that they had had an excellent autumn
migration with nearly 30000 honey buzzards being counted migrating over the
Rock, with the peak days being 5092 on 3rd September and 4332 on 6th.These would
be mainly adult birds from western and middle Europe and Scandinavia.
Both signals today (22nd September) were from the same location as on the 20th, possibly a little bit to the north-west. The weather map shows a band of cloud over the area where the honey buzzard is located, with north east winds, so presumably he is waiting for clear skies before continuing on into Africa.
During the night of
23rd-24th, the male honey buzzard was south of the Jebel Sarho mountains
and well south of the High Atlas, about 250 kilometres south of his previous
position. On 24th, he was actively migrating SSW and by evening had arrived near
Khorb el Ethel, in the western deserts of Algeria. A day journey of about
300 kilometres shows that he is
moving steadily towards the wintering
range.
On 26th September the male was migrating over the Sahara Desert in Algeria and approaching the border with Mali. He is clearly heading straight across the deserts and heading for the equatorial forests. Today the weather is clear over the area where he is travelling and the wind is light to fresh north-easterly.
He had a very good day's migration on 28th September, covering nearly 400 kilometres to the SSW into Mali. He had left the main deserts and was crossing the Sahel, with the larger river systems and woodlands in front of him. This was his 23rd day on migration.
At 0290am on 30th September, the male was roosting near Dialakoro, just south of Bamako - the capital of Mali. He had covered 283 kilometres since the last signal. His migration heading was more to the south-east as he crossed south over the Niger river. Winds are light and there are thunderstorms to the east. He appears now to be heading for the Ivory Coast and his position today is 5032 kms from Inverness. By 2308pm on 30th, he was near the river Bagoe, near Ouola, in southern Mali after migrating SE for 165 kilometres during the day.
The male honey buzzard is in
the tropical forests of Ghana. During the night of 1st/2nd October he was
near Ouo in Burkina Faso. The visibility was excellent, light south-west
winds, over 80F during the day with occasional thunderstorms. On the 2nd
October the bird travelled 343 kilometres and by nightfall was in the forests
beside the White Volta river, south
of New Tamale in northern Ghana. He
is now in typical wintering habitat for honey buzzards but he may continue
to move to his chosen wintering site, which is probably where he lived in
previous winters. His journey from Scotland has taken just 28 days and the
direct great circle d istance is 5399.8 kilometres. His true flight distance
over the ground, calculated from the transmission locations en route, is 6239
kilometres or 3900 miles. This is an average daily journey of approximately 223
kilometres (139 miles).
The radio on the male will
continue to transmit every two days until 1st November so we will be able
to find out if he continues to a chosen wintering area or moves around. After
that the radio's program will slow down and send transmissions to the
satellite every 10 days. Once his spring migration starts it will return to a
two day cycle and show us his
return to Scotland, assuming he survives
the winter in Africa.
On 4th October, the male
moved eastwards through Ghana and in the morning was in the Oti river area
in the east of Ghana; 158 kilometres east of his position on 2nd. By nightfall,
he had travelled a further 105 kilometres to the north-east into the Republic of
Togo, and appeared to be in forested regions NW of Bassar. The weather reports
were overcast with
light south-west winds and scattered thunderstorms. Some
of the changes in migration directions may be due to avoiding the worse
thunder areas, but this old experienced bird will be well used to tropical
thunderstorms. He is clearly still heading towards his wintering
site.
On 6th October the bird was in Benin. I received two very accurate positions from the Argos tracking station. Overnight on 5th/6th, he was roosting just E of Djougou and by the evening he had moved 148 kilometres to the ENE across Benin. He has not yet reached his wintering grounds.
On 8th October, the male honey buzzard was migrating actively through Nigeria. By chance, I received good positions during the night when the bird would have been roosting. Overnight on 7th/8th he had moved 75 kilometres from his previous position in Benin, but during the 8th, he flew 245 kilometres ESE through Nigeria and crossed the River Niger. On 10th October, he spent the whole day near Abuja, 93 kilometres east of his position on the 8th. Signals on 12th, 14th and 16th came from the same locality and it is starting to look as though this may be the wintering site. His present wintering area is 7063 kilometres from his breeding site and his migration lasted 35 days.
After spending 10 days in the Abuja area, with daily journeys of up to 20 kilometres, the male moved on 20th October. Overnight he had roosted in his usual location but by nightfall he had moved 210 kilometres to the SSE to locality to the south of Okua.
Over the last 8 days the
male has migrated a further 1124 kilometres to the south, bringing the total
distance from its Scottish nest site to 8420 kilometres. On the 22nd, he
migrated 170 kilometres through Nigeria to rest the night on the Cameroon
border. Next day he moved a small distance further south, but on 24th he flew
for 240 kilometres, starting near
Mundemba in Cameroon, he passed the 13325
feet high Mount Cameroon during the day and reached a coastal area near
Kribi by dusk. On the 25th, he moved 184 kilometres to an area SW of Bata in
Guinea and next day he flew for 200 kilometres, passing Libreville during
the day, and crossing a big inlet of the sea to reach Donguila in Gabon.
On the 27th, he crossed the Equator and roosted overnight in the eastern border
of the National Park of Wonga Wongue, Gabon. Yesterday, he flew a further
53 kilometres to reach coastal forests in the Ogooue Maritime of Gabon.
It is most interesting that the male honey buzzard restarted his migration, after spending 10 days in Nigeria and we wonder how much further south he will travel. A honey buzzard ringed by Brian Etheridge in the Scottish Highlands was reported from Guinea in 1991. He had moved a further 20 kilometres to the south by 30th October and is now settled there in coastal forests of Gabon. A transmission on 12th November was from that locality. The transmitter has now switched to 10 day intervals and will remain in that mode until April when we hope to track the return migration at two day intervals. Updates will now occur several times per month when interesting data is received.
Transmissions have been received at 10 day interval between 12th November to 12th March 2003. His positions on these dates were all within 20 kilometres of each other in his wintering area, and some of the earlier ones indicated that he was not roosting in the same place each night. An incomplete signal was received on 22nd March. No signals have been received since then, even though the radio was due to change to fast transmissions on 21st April, and we have to conclude that the battery is finished.
Male's radio ceased transmitting on 22nd March; he was last located in coastal Gabon, south of the Equator on 12th March. We conclude the battery had run down prior to his spring migration.
On 24th May, Darrin Madgin reported a honey buzzard carrying a satellite transmitter flying west over Sussex, and we think that this was likely to be the male, whose radio stopped transmitting in March.
Juvenile Honey Buzzard
21250
The single chick of the above adult male and its mate was ringed in its nest on 10th August 2002, and fitted with a satellite transmitter. This bird has the same parents as the two chicks tracked in 2001 (see below). Despite the rather poor wet weather, the chick weighed 1010 grams and was well fed with wasp grubs. Its wing length was 292 mm so we expected it to remain in the nest for at least another ten days.
Its male parent left on 5th September when the chick was still located in the nesting wood. On the 10th it roosted about 10 kilometres away but then returned to its natal site, until 15th September when it was located south of Inverness. At this time, the mornings were foggy but afternoons and evenings were sunny with clear skies under high pressure.
There were no signals expected on the 16th and on the 17th September the bird was migrating through the Perthshire Highlands and on to central Scotland between Glasgow and Edinburgh. It covered about 60 kilometres in 5 hours during the afternoon of 17th. At present, it is not taking the westerly route followed by the young birds last year. On 19th, the youngster remained in same area of the Carron Valley Forest. It is presumably feeding in the Forestry Commission woodlands.
By nightfall on 20th
September, the young honey buzzard had moved 45 kilometres southwards to Broken
Cross Muir, near Douglas Water. The evening transmission on 22nd showed that the
bird had been migrating strongly. It had travelled 480 kilometres due south in
the two day interval and is now near Bridgend in South Wales. At this speed the
bird could easily
be in France when we receive the signals on the 24th
September. The forecast is good for tomorrow with clear skies from Wales to
France, but there will be fresh NE winds across the sea.
On 24th September, the young
honey buzzard was in trouble and clearly illustrating the migration
hazards that can befall long distance migratory raptors from Scotland. The
morning signal at 1030 showed him to be over the open Atlantic Ocean south
of Ireland and about 660 kilometres west of Land's End. Although the skies
on 23rd were clear, the bird had veered westwards over the sea and with fresh to
strong easterly winds had apparently not reached France or Cornwall. Signals
during the day showed that he was flying downwind across the Ocean and by 1620
was about 700 kilometres WSW of Cape Clear in south-west Ireland. It is
difficult to predict whether the bird will redirect its migration, land on a
boat or
sadly be lost at sea. Hopefully, transmissions in two days will
be favourable.
Incredible!! The young honey
buzzard is still flying and sadly he missed the outermost island of the
Azores during the night. Today the first signal was at 0157am and a further 5
signals to 0846am showed that he was moving strongly to the south. He is
now in the middle of the Atlantic Ocean well south the Azores. Today's
satellite photos show that a low pressure
is over the Azores and he is
travelling southwards in the strong northerly winds behind (west of) the low.
There are belts of cloud and the wind is at least 40-60kms/hour; by this
afternoon he should be picking up the strong west winds blowing towards the
Canary Islands and Africa. Again we wonder if he has enough fat reserves to
survive. The strong winds may
assist him towards land or he might land on a
boat, but the nearest land is a very long distance.
This bird's flight is already an incredible feat. It cannot land on water, so it has been flying continuously since the 23rd September without stopping and without feeding. The link lines on the map between 22nd, 24th and 26th are not the true tracks - the bird undoubtedly flew longer tracks around the weather systems. The next signals are due on 28th.
Two signals were received overnight on 27th/28th September. The one very accurate signal gave a position approximately 280 kilometres to the NW of Madeira, north of the Canary Islands. This was 2240pm on 27th. It would be very encouraging to think that the bird then turned towards the island and the lack of later signals was due to it being in woodland or cliffs on Madeira. But we will need to wait another day for the next signals. By this time the honey buzzard had been in the air for over 100 hours and would undoubtedly be reaching its limits. It had travelled in strong westerly winds for nearly 1400 kilometres since the last signal on the 26th. Now we wait and hope.
Last night, 29th September, two signals were received. But there were no further reports after 1727GMT. The position at this time was 27 kilometres to the south-west of that received at 2241GMT on 27th. The signals were both accurate to within one kilometre, so it suggests that it is either on a fishing boat or on a floating object in the sea. The weather has been cloudy, with rain and thunder showers in that sea area and the wind is variable. Unfortunately, during the young honey buzzard's journey of nearly 5000 kilometre, much of it being swept along by strong winds, over the Atlantic Ocean he missed both the Azores and Madeira, by relatively small distances. The bird is in an remote area of sea being 300 kms from Madeira, about 600 kms from the Azores and about 1000 kms from both the southern tip of Portugal and the Moroccan coast. It is difficult to predict if we will get any more news.
This incredible journey has already revealed both the hazards of migrating from Scotland to Africa and also the stamina of a bird which a month ago had only just learnt to fly. For many people, this young honey buzzard is now a "well known" individual whose plight, as it has flown day and night over the wide Atlantic, has caused us to wonder and also to hope it has a safe landing. But how many other young honey buzzards and ospreys have perished unknown in the Ocean migrating to their wintering grounds in West Africa. There is no doubt that one of the messages to come out of this study is that the small number of honey buzzard nests in Scotland need special conservation to ensure that the maximum number of healthy young are reared so that at least some will successfully reach West Africa. Those that survive are likely to make certain in future years that they take the short sea crossing over the English channel like this year's male.
The latest signals coming in
this morning, 1st October, show that the bird is still moving slowly
southwest. The position at 0510am was 55 kilometres SW of its position on 29th.
By the time of the last signal at 0933 the bird had moved another 4.7
kilometres. It suggests that it is resting on something floating in the
sea which is being carried SW by the sea currents and
winds; it would be
good to think it might be on a fishing boat. But we do not know.
Transmissions received early
this morning (3rd October) indicated that the young bird is still drifting in
the open Atlantic Ocean, well over 300 kilometres from Madeira. He is clearly
not on a fishing boat but is slowly drifting south-westwards at about 1km/hour
in the sea currents. The bird's position had moved 35 kilometres since the 1st
October and the last signal at
0453GMT this morning was at 34.779N and
19.975W. The clarity of the signals suggested the bird is on something floating
in the sea rather than being in the water. It is not possible to say if it is
dead or alive, but it is now a very long time since it left land on 23rd
September and it is not possible for it to feed while at sea. Birds of prey can
last long periods without food but it would be incredible if this youngster was
still alive after its massive flight. Sadly, on the very day that its
father reached his wintering area in the tropical forests of Ghana, we have to
conclude that this amazing young bird is probably dead.
Last night, 4th
October, seven signals were received between 1604pm and 2119pm, including two
locations accurate to within 350 metres at 34.869N 20.303W. This position is 31
kilometres further west and is now 363 kilometres from Madeira. It is now only
drifting at 140 metres per hour, presumably on calm seas and overcast skies.
There has been considerable interest and concern from around the world for
the lost young honey buzzard and we are grateful to the many people who emailed
about its sad plight, with hopes that it might yet get to land. But it is
now so long since the bird left land that we sadly have to conclude it has
died. Some people emailed with news of honey buzzards and ospreys which
they had seen from ships in the Bay of Biscay and which they thought at
the time would have died at sea, now they know that some of these migratory
raptors can safely make land after incredible over water migrations. But
unfortunately, our bird was pushed far too far out to sea by the stormy
weather but earlier in September, a young Scottish osprey we were tracking
successfully returned to land after being blown out to sea ( see below and at
www.ospreys.org.uk). More signals
were received from the same place on 6th October, it is now drifting
slowly in the doldrums. With disappointment we conclude that the honey buzzard
is dead but it's body is on a floating object on the sea and still transmitting.
No signals were
received on 8th October which confirms that the bird has
died.
There has been great interest in the incredible exploits of this bird and the continuing migration of the male bird in Africa. Sincere thanks for all the interesting and encouraging emails which we have received, and for the very kind offers of support and donations for us to continue our conservation work.
Migration Journey
DATE |
LATITUDE |
LONGITUDE |
LOCALITY |
14/09/02 |
57.483N |
04.166W |
Inverness at nest |
15/09/02 |
57.374N |
4.058W |
Moy, south of Inverness |
17/09/02 |
56.464N |
4.143W |
Loch Tay, Perthshire |
17/09/02 |
56.086N |
3.965W |
W of Denny, SW of Stirling |
19/09/02 |
56.100N |
3.998W |
SW of Stirling |
20/09/02 |
55.615N |
3.765W |
Douglas Water, Lanark |
22/09/02 |
51.477N |
3.579W |
Bridgend, W of Cardiff |
24/09/02 (1030am) |
49.388N |
15.149W |
Atlantic Ocean, 660 kms west of Land's End |
24/09/02 (1620pm) |
49.537N |
18.817W |
Atlantic Ocean, ca 700 kms WSW of Cape Clear, Ireland |
26/09/02 (0157am) |
37.404N |
35.928W |
ca250 kms SW of Flores, Azores |
26/09/02 (0846am) |
34.433N |
34.240W |
mid Atlantic Ocean. ca1300 kms WNW of Canary Islands |
27/09/02 |
35.166N |
19.012W |
Atlantic Ocean, NW of Madeira |
30/09/02 |
35.012N |
19.246W |
82kms SW of above position |
4/10/02 |
34.859N |
20.303W |
dead at sea 363 kms from Madeira, Atlantic Ocean |
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