Sweden is now witnessing the largest movement of Pallid Harriers ever to occur in the country

This week we are hearing some great news about Pallid Harrier breeding in Finland and now you can watch one of the females as she migrates to winter in Africa. Just as exciting Sweden is now witnessing the largest movement of this species ever to occur in the country and already a few Pallid Harriers have arrived in Shetland. Are we going to witness such movements this week with this high pressure over us and easterly winds! Could they be another contender for breeding in Britain? Or will the selfish Red Grouse shooters deny us all the pleasure!

Potku the Pallied Harrier

Potku the Pallid Harrier

In late June 2015 a female pallid harrier (Circus macrourus ) breeding in Utajärvi, Northern Ostrobothnia, Finland was fitted with GPS/GSM transmitter. Being still a rare breeding species in our country, this marked the first occasion that a pallid harrier so tagged in Finland. The main breeding area of the pallid harrier covers the steppes of Russia and Kazakhstan. It is quite a mystery how and why the species has begun to breed in Finland.

By means of the transmitter we hope to shed light on female’s use of her breeding territory as well as, especially, her migration behaviour and overwintering areas. In recent years a growing number of pallid harriers have been observed in France and Spain between September and April. This leads one to guess whether some of the pallids breeding in Finland might opt for this migration route instead of the well-known route through the Middle East.

The transmitter was fitted by Ari-Pekka Auvinen and Julien Terraube, the latter of whom has studied pallid harriers in Kazakhstan. The transmitter is powered by a solar panel and weighs 17 grams. It was supplied by Beatriz Arroyo’s research group from the The Institute of Research in Game Resources, Madrid.

The female was named Potku which is Finnish for (a) kick. Potku is also the name of the remote village situated close to her breeding site in 2015.

Unlike in Kazakhstan, at least some of the pallid harriers breeding in Finland are philopatric (i.e. return to the same site to breed). We hope to know more about this issue when, if everything goes well, Potku returns to breed in Finland in 2016.

Joins us to follow Potku’s journey and gain an insight into the behaviour of this fascinating species!

Autumn Migration

Potku's nestlings

Potku’s nestlings
One of Potku's fledglings in flight. Notice her bulging crop, which is full from a hazel grouse meal.

One of Potku’s fledglings in flight. Notice her bulging crop, which is full from a hazel grouse meal.

NB! The times shown on the map are always in GMT. Its difference to e.g. Finnish time is -2 hours and summer time -3 hours. The times may be given as local time in the text. If so, the text will mention it.

Note inserted here by the Editor of Raptor Politics:

When we view this huge migration distance covered by Potku after leaving Finland, we are reminded of the five male hen harriers which disappeared this year, and the two 2014 satellite tagged fledged hen harriers that vanished last year from territories here in England. It was significant all seven harriers never managed to fly more than 5 miles from their territories before they each vanished from the face of the earth.

September 15–23 2015

Goodbye Europe

Now we know one big thing about Potku’s overwintering: she did not stay in Europe.

The female pallid harrier spent eight days in the Eure-et-Loir department southwest of Paris after which, on the morning of September 19, she started to fly resolutely towards Africa. The first night she spent east of the city of Poitiers in western France. The next night remains a slight mystery since Potku was still flying around midnight local time somewhere near Zaragoza in northern Spain. A few hours earlier she had crossed the Pyrenees near the Bay of Biscay between Biarritz and Pamplona. The highest mountains on her route were about 1 000 metres high – flying this way she avoided having to climb over the highest peaks of the Pyrenees.

Potku didn’t spend a lot of time in Spain. The second one of her nights in the country she spent on a field 70 km inland of Alicante, the third already close to the Alboran Sea east of the port town of Almeria. On Wednesday morning September 23 the pallid harrier headed to the western end of Mediterranean and made the 200 km sea flight in seven hours. In Morocco she flew another 150 km inland and settled for the night on a hill that, in satellite image, looks quite dry and barren.

September 10–14 2015

Over Paris

The fields of Picardy didn’t hold Potku for longer than an hour after all. Just before noon on Thursday September 10 she continued her journey southwest. After five pm local time the bird was already in the western airspace of Paris. Potku crossed the city of love across the large Bois de Boulogne park, not far from the Roland Garros stadium well-known for hosting the French Open tennis tournament. Soon after this the pallid harrier must have looking at the symmetrical gardens of Versailles as she flew by two kilometres east of them.  The next night she spent at a woodland patch a good 50 km southwest of Paris. The next morning, Friday 11th, Potku flew another 20 kilometres to reach her next stopover destination near the village of Voise in the Loire valley.  There she’s been hunting until now, Monday evening September 14.

September 7–10 2015

Hitting the Gallic roosters*

On the morning of September 8 Potku must have had enough of commuting between the beech forests of Huy and the wetlands of Großes Bruch in Central Germany when she got on her flight gear again. The first day’s leg was a moderate 60 km flight towards southwest to the city of Göttingen where she spent another night in a forest patch surrounded by arable fields. After this the bird embarked on her longest day flight to date: 400 km  in 12 hours to the border between Belgium and France. When writing this, Potku has already moved well into France:  she seems to be hunting on the fields south of the village of Burelles in the region of Picardy in Northern France.

* Yes, I believe she could hit a small rooster, or at least a chicken, if need be. I recently showed the remnants of a prey item from last summer’s nest site to an expert: the bones and feathers had belonged to a female black grouse, which weighs on average (1 kg) twice as much as Potku.
August 31 – September 6 2015

In the middle of Germany

What happened during the first week of September can be told in a few words: Potku got stuck in the middle of Germany. On the last day of August the female pallid harrier flew 110 km in six hours from Bad Belzig to the border between Saxony-Anhalt and Lower Saxony. Here, on the fields west of Neuwegersleben, Potku has spent a whole week. In addition to regular cultivated lands, the Neuwegersleben district boasts also the protected wetlands of Großes Bruch where Potku hunted for three days. The two last nights she has slept at another protected area, the hills of Huy, in one of the largest almost pure beech forests of central Europe.

August 24–30 2015

Back to Poland

Did she forget something? After having spent two nights in eastern Germany Potku turned back to the direction she came from. Well, in the end, she didn’t go too far back: Flying 50 km northeast to Poland seems to have sufficed. Potku spent the next six days on the fields between the small villages of Kowalów and Lubiechnia Mala*. On August 30 she seems to have resumed her travelling mode and continued in the western direction she was heading before. When writing this, Potku is situated near Bad Belzig 70 km southwest of Berlin.

* The poetry of the places she visits continues. Could there a much more beautiful name for a village than Lubiechnia Mala. As far as I know and have been told, Lubiechnia does not really mean anything.  Yet the name sounds, to me at least, like it could be based on the Slavic word for love (lubit in Russian, lubowac in old Polish). Mala, for its part, is Polish for little (one).   
August 22–23 2015

Then she takes Berlin.

Potku spent two nights in Poland. First, after resting the night approximately 100 km northwest of Warsaw, she flew 270 km west-southwest. Her route was dead straight and apparently she flew quite high: The GPS-tag does not measure altitude yet there was a sharp ten degree drop in temperature when she took off. After flying over the historic city of Poznan she settled for the night at a woodland patch near the small village of Wasowo. However, something must have happened during the night. During the hours when her tag was offline (24–06 Polish time) she had moved another 30 km towards Germany.

On Saturday August 22 Potku crossed the border between Poland and Germany a little south of Frankfurt an der Oder. Form there she had only a short flight to her next stop at the east bank of Lake Scharmützelsee.

Here Potku rested here for a little longer. Maybe she wanted to feel the vibes of a European capital: the distance between her two consecutive roosts and the Brandenburg Gate is only 55 km.

August 17–21 2015

Potku turned west.

For Potku Latvia was only a one night affair. On Monday 17 she flew some 160 km southeast to northeastern Lithuania where she stayed the night at fields north of the town of Utena.  Next morning at 11 o’clock it was time for her to carry on again and change countries. This time Potku decided to leave western democracies and try her luck in Belarus.  There she spent two nights: from Tuesday to Wednesday near the city of Lida and from Wednesday to Thursday at the outskirts of Shchuchyn.  Come Thursday morning she must have felt to urge for travel and freedom again when she turned west-southwest towards Poland. At the time of writing this, on Friday 21, Potku is waking up to the morning well into the heartland of Poland. She sure didn’t fly straight south!
During the past couple of days, a read ringed young female pallid harrier has been seen south of Stavanger in western Norway. The code of the ring is not quite clear yet, but practically there are only two options left: either a nestling ringed in Sievi on June 29 or one of the daughters of Potku!

August 13–16 2015

A lot can happen over one weekend: Potku is now in Latvia!

After having spent a couple of days on the southern banks of Lake Oulujärvi and near the towns of Lapinlahti and Siilinjärvi in Northern Savonia the female pallid harrier started to fly briskly in a south-southwestern direction. At 9 in the morning on Friday 15 she was flying above the city of Kuopio. Only seven hours later she was some 250 km away in Virolahti by the northern coast of the Gulf of Finland heading oversea to Russia!

After crossing the Gulf of Finland in two hours she settled for the night in a forest 20 km southeast of the town Ust-Luga near the Estonia–Russia border. In the morning Potku resumed her south-southwestern direction and flew by the eastern shore of Lake Peipus towards Latvia. The next night she would spent near Latvia’s biggest lake, Lake Lubans.

If Potku continued to fly in this direction she would eventually fly through Belarus, Ukraine and Romania and end up in Greece before facing the Mediterranean.   Is she really flying straight over to Africa already or will her course change anytime soon?

August 7–12 2015

The first sings of Potku ’s fledglings having become independent were received on August 7 when she moved permanently a few kilometres north of her breeding territory. Here she stayed a couple of days until, at noon on August 10, she took a bearing south. Potku flew approximately 50 kilometres to the southern edge of lake Oulujärvi – and to where exactly!

The Finnish basic map is dotted with poetic, funny as well as downright rude names of places. One of my favorites is Pahamaailma, Bad World, is Suomussalmi near the border to Russia. I haven’t been there yet, but some day… On one of the unlucky days this summer, after having spent hours in vain searching for pallids, I decided to fulfil one dream and visited Hevonvitunsuo, Horse Cunt’s Mire, in Kiiminki. However, it is the mire that Potku chose for her first night’s resting place that is at the top of my list: Iso-Onneton, The Big Unhappy, the most poetic of them all!

On Tuesday August 12 Potku seems to be moving gradually south east towards the village of Ojanperä in Kajaani were we searched for the nest of another pair of nesting pallid harrier earlier this summer with no luck.

This paper was written by  Ari-Pekka Auvinen, photos: Ari-Pekka Auvinen, Web management: Markus Piha


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