“Picotin” the sole chick reared by Picoto in 2013m just days before leaving its territory.
Honey Buzzard (Pernis apivorus), juvenile, Valle del Jerte (Cáceres), 28th August 2013
Picoto, the first Iberian Honey Buzzard (Pernis apivorus) tracked by satellite, was the star of a popular posting in this blog which attracted even the press. On that occasion we told the story of his outward and return journeys between Spain and Liberia and of his travels in Liberia during the winter of 2012-2013. His next journey to Africa has also been the object of attention and the information obtained has been of great interest.
Covering 365 days, a complete year, from the first migration, the time spent migrating has been 33 days (9%), the time spent in Extremadura has been 111 days (30%) and the period in his winter home in the Liberia forests has been no less than 221 days (61%). In the two years of the study Picoto has occupied the same territories and the same nest, demonstrating that Honey Buzzard show a great faithfulness to both breeding and wintering areas.
Notwithstanding that the information is partial, Picoto’s movements in the Jerte valley were limited to a well-defined breeding territory, with some differences between the first part of spring (May – June, in the red circle and upper left map) compared with summer (July – August, green circle and upper right map). At the start, contact with Picotowas in the lower part of the valley, with no difference between the sunny and shady slopes. In the later months almost all of the activity was on the sunny slopes with a wider range of altitude, crossing the Jerte River towards the south on two occasions. Outside his territory, he only showed a short displacement down the valley to Rebollar and once outside the Jerte valley to Hervás.
Almost all of the contacts with Picoto were from within Pyrenean oak woodland (Quercus pyrenaica), which is a habitat under much pressure in the Jerte valley, having lost much of its area and quality over the last few decades, as a result of the unstoppable spread of cherry production. This photo of part of Picoto’s territory clearly shows the high level of fragmentation of the oak woodland. Given that Picoto spends seven months a year in the Liberian forest, his problems do not end here, as in Africa also there are threats to the forest, illegal logging for timber for example, which are even more serious.
The post-breeding migration in 2013 was very similar to that undertaken in 2012. Picoto left the Jerte valley on 29th August; in two days reached the Straits of Gibraltar and crossed toÁfrica on the morning of 31st August, crossing the 30 kms of open sea over the Atlantic and reaching the African coast next to Tangier. In 2012 he crossed the straits on the morning of 1st September, just a day later. Between the 2nd and 7thSeptember Picoto crossed the Sahara, the second great geographic barrier that he had to encounter. After crossing the savannahs of the Sahel belt he entered more forested areas. Finally on 15th September he reached the wintering area, the jungles of eastern Liberia , after 16 days and 4,000 kms journey across Morocco , Algeria , Mauritania , Mali , Guinea and Liberia , flying over open sea, mountains, deserts, savannahs and forests. Since then, as in 2012, the signals from Liberia have been sporadic, presumably because the deep canopy cover of the forest there impedes the correct working of the solar-powered transmitter.
The data obtained agree with other studies carried out in Europe . For example, with eleven Swedish Honey Buzzards tagged, they show that the adults maintain, as does Picoto, small permanent territories in the African forest (stars), whilst the juveniles first of all spend some time in the northern zone of the forest belt and then move in the months that follow between 2,400 and 4,000 kms, without fixed territories or fixed travel direction and without return to Europe during their second year (Strandberg et al. 2012).
All of these findings have been possible thanks to SEO/BirdLife and the Junta de Extremadura. The work forms part of the Programa Migra of SEO/BirdLife.
Strandberg R., Hake M., Klaassen R.H.G. & Alerstam T. 2012. Movements of immature European Honey Buzzards Pernis apivorus in tropical Africa . Ardea 100: 157–162.
“Picotin” the sole chick reared by Picoto in 2013m just days before leaving its territory.
Honey Buzzard (Pernis apivorus), juvenile, Valle del Jerte (Cáceres), 28th August 2013
Picoto, the first Iberian Honey Buzzard (Pernis apivorus) tracked by satellite, was the star of a popular posting in this blog which attracted even the press. On that occasion we told the story of his outward and return journeys between Spain and Liberia and of his travels in Liberia during the winter of 2012-2013. His next journey to Africa has also been the object of attention and the information obtained has been of great interest.
Covering 365 days, a complete year, from the first migration, the time spent migrating has been 33 days (9%), the time spent in Extremadura has been 111 days (30%) and the period in his winter home in the Liberia forests has been no less than 221 days (61%). In the two years of the study Picoto has occupied the same territories and the same nest, demonstrating that Honey Buzzard show a great faithfulness to both breeding and wintering areas.
Notwithstanding that the information is partial, Picoto’s movements in the Jerte valley were limited to a well-defined breeding territory, with some differences between the first part of spring (May – June, in the red circle and upper left map) compared with summer (July – August, green circle and upper right map). At the start, contact with Picotowas in the lower part of the valley, with no difference between the sunny and shady slopes. In the later months almost all of the activity was on the sunny slopes with a wider range of altitude, crossing the Jerte River towards the south on two occasions. Outside his territory, he only showed a short displacement down the valley to Rebollar and once outside the Jerte valley to Hervás.
Almost all of the contacts with Picoto were from within Pyrenean oak woodland (Quercus pyrenaica), which is a habitat under much pressure in the Jerte valley, having lost much of its area and quality over the last few decades, as a result of the unstoppable spread of cherry production. This photo of part of Picoto’s territory clearly shows the high level of fragmentation of the oak woodland. Given that Picoto spends seven months a year in the Liberian forest, his problems do not end here, as in Africa also there are threats to the forest, illegal logging for timber for example, which are even more serious.
The post-breeding migration in 2013 was very similar to that undertaken in 2012. Picoto left the Jerte valley on 29th August; in two days reached the Straits of Gibraltar and crossed toÁfrica on the morning of 31st August, crossing the 30 kms of open sea over the Atlantic and reaching the African coast next to Tangier. In 2012 he crossed the straits on the morning of 1st September, just a day later. Between the 2nd and 7thSeptember Picoto crossed the Sahara, the second great geographic barrier that he had to encounter. After crossing the savannahs of the Sahel belt he entered more forested areas. Finally on 15th September he reached the wintering area, the jungles of eastern Liberia , after 16 days and 4,000 kms journey across Morocco , Algeria , Mauritania , Mali , Guinea and Liberia , flying over open sea, mountains, deserts, savannahs and forests. Since then, as in 2012, the signals from Liberia have been sporadic, presumably because the deep canopy cover of the forest there impedes the correct working of the solar-powered transmitter.
The data obtained agree with other studies carried out in Europe . For example, with eleven Swedish Honey Buzzards tagged, they show that the adults maintain, as does Picoto, small permanent territories in the African forest (stars), whilst the juveniles first of all spend some time in the northern zone of the forest belt and then move in the months that follow between 2,400 and 4,000 kms, without fixed territories or fixed travel direction and without return to Europe during their second year (Strandberg et al. 2012).
All of these findings have been possible thanks to SEO/BirdLife and the Junta de Extremadura. The work forms part of the Programa Migra of SEO/BirdLife.
Strandberg R., Hake M., Klaassen R.H.G. & Alerstam T. 2012. Movements of immature European Honey Buzzards Pernis apivorus in tropical Africa . Ardea 100: 157–162.
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