WINTERING PALLID SWIFTS IN ALANGE, BADAJOZ

Pallid Swift (Apus pallidus). Mérida, 01.03.2012. By Ángel Sánchez.

This blog post summarises a collaboration by Jesús Solana, author of the observations listed below. Fellow observers for the 6.12.2011 record were Vanessa de Alba, F. Castro and Antonio Núñez. The only observer on 11.12.2011 was Lorenzo Alcántara.

The Pallid Swift (Apus pallidus) is a summer visitor to Europe, wintering in Africa between the southern Sahara and the Equator. It stays in Extremadura much longer than the Common Swift (Apus apus), from which it is sometimes very hard to distinguish on the wing. The bookend dates in Cáceres are 1 February and 22 November, with arrival before 16 February in one third of the years. There is prolonged passage across the Straits of Gibraltar lasting from February to June in spring and from July to November on the return passage to Africa. There have also been one-off sightings in December and January in various points of the Iberian Peninsula (Prieta and Molina, forthcoming). In Extremadura's case there were no December records before the ones listed below and only one previous January sighting is known, on 24.01.2009 in Mérida by Jesús Solana.

In the village of Alange in Badajoz the first winter sighting of nine birds was made at dusk on 04.01.2010 from the village water tank. On the following day, 05.01.2010, another nine swifts were spotted from the same site. In this same month other observers saw Pallid Swifts at Alange Reservoir(08.01.2010; Ferguss Crystal) and in the industrial estate of Mérida (13.01.2010, Ángel Sánchez). In January 2011 there were other swift sightings in Alange: flocks of 15 and 11 birds on 04 and 05.01.2011. Next winter, the third in a row, six swifts were seen from the water tank and the church square on 29.11.2011, this time being definitively identified as Pallids. One bird was also seen entering roosting holes in the church called Iglesia de Nuestra Señora de los Milagros (see photo).

Half-hour visits were made to Alange between 01.12.2011 and 15.02.2012 in an attempt to ascertain the status of these swifts, always 15 minutes each side of dusk, though the ideal observation period would have been a full hour, 30 mins before and after dusk. Swifts were seen on all visits, as shown in the enclosed graph, with a minimum of seven and maximum of 15 on 06.12.2011, when there were four observers. Numbers seem to fall away as winter progresses, for unknown reasons, maybe because not all of them survive, maybe because some do migrate. One interesting fact is that all the birds roost in building-façade holes, entering in pairs. Fifty of the 58 records are of two birds sharing the same roosting hole and the remaining 8 records are of birds entering singly. This video shows Pallids entering their roosting holes on 27.12.2011 when the church was decked out with christmas decorations.

The commonest bird on Alange Church is the feral pigeon; there are also Spotless Starlings and several Stork's nests providing refuge for House Sparrows. Several of the nesting/roosting holes are occupied by the pigeons and disputes have been observed on three occasions between swifts and starlings for the same holes, though the starlings do not seem to oust the swifts in winter. Partially filled-in holes tend to favour the swifts over the starlings.

Wintering of Pallid Swifts in Alange in 2011/2012 would not seem to be an isolated event, judging from the sightings in previous winters. No recent similar situations are known in Spain, though something similar was described for Seville three decades ago (Cuadrado et al., 1985). Alange is fairly similar in its features to other towns and villages of Extremadura, but no other January observations are known apart from a couple of January sightings in Mérida (2009 and 2010). In 2011/12 searches were made in Mérida, Hornachos, Valverde de Mérida and Palomas in an attempt to find other wintering sites but the results were always negative.

Sources:
- Prieta, J. y Molina, B. En prensa. Vencejo pálido Apus pallidus. En, Atlas de las Aves Invernantes en España. SEO/BirdLife. Madrid.
- Cuadrado, M., Arjona, S. y Rodríguez, M. 1985. Hibernage du Martinet Pâle Apus pallidus dans le sud de l’Espagne. Alauda, 53: 306-307.

AUTUMN PASSERINE MIGRATION THROUGH THE SIERRA DE GATA

This post has been sent in by Jesús Serradilla Rodríguez and we'd like to thank him for his collaboration. It goes without saying that this blog is open to anyone interested in telling us anything about Extremadura's birdlife.

On 31 October 2011 a 2-hour count (08:30 to 10:30) was made of southward passerine migration through Sierra de Gata. The counting site was the pass called Puerto Viejo de Robledillo de Gata (Cáceres) on the border with Salamanca Province. Most birds were flying in single-species flocks, though there were also some mixed-species flocks, especially multi-finch flocks and Chaffinches with Meadow Pipits. The total count came out as 161 flocks and 757 birds; 13 different species were identified. The commonest were Chaffinch (63% of the total), Meadow Pipit (9%) and Goldfinch (7%). On the days before and after the count there was also visible migration of Linnets, Crag Martins and Corn Buntings. On other dates intense migration of Bee-eater and Swift was observed. It should be stressed here that our lookout point was only one shoulder of land among many in Sierra de Gata, ostensibly without any characteristic that might favour passage. From this pass, and also from the neighbouring pass of La Ventanera just to the east, the passage is funnelled through the valley of River Árrago towards the Cáceres plains.

At the moment an Environmental Impact Statement is pending on the 60-generator windfarm that would be set up precisely on the Salamanca side of this part of Sierra de Gata. The mockup below shows how windpower generator AR17 would be sited on the lookout point used in this count, and the AP1 on the shoulder of land known as Collado de La Ventanera. The compulsory Environment Impact Study before the actual ruling included an ornithological study. This study omitted this important passage point and even downplayed the importance of Sierra de Gata as a whole for bird migration. The simple study we conducted has shown that the passage of certain species tends to be concentrated in a few days at specific times. They are therefore species that might well be underestimated if the counts are not made at the right point and time. This sizeable passage is yet another reason for conserving these exceptional though overlooked sierras in western Iberia.

JANUARY 2012: NOTABLE SIGHTINGS IN EXTREMADURA

Little Bustard (Tetrax tetrax). Flock of 700 birds at La Serena (Badajoz) on 29/01/2012
(Santiago Villa / Spainbirds Nature Tours).

A list of the most notable January 2012 records sent to the GOCE birdwatching forum. Compiled by Sergio Mayordomo. The Vegas Altas Censusing Team (ECVA in Spanish initials) is made up by: Luis Lozano, Juan Pablo Prieto, Fernando Yuste, Ángel Sánchez, Ángel Luis Sánchez, Atanasio Fernández, Benigno Cienfuegos, Domingo Rivera, Javier Caldera, Javier Prieta, Manuel Gómez Calzado, Marcelino Cardalliaguet and Sergio Mayordomo.

- White-Fronted Goose: Three birds at Lugar Nuevo, Peraleda de la Mata (Cáceres), on 03/01 (Sergio Mayordomo; photograph).
- Barnacle Goose: One bird at La Trebolosa, Madrigalejo (Cáceres), on 14/01 (Javier Mahillo and César Clemente). On 18/01 one bird was seen at Madrigalejo (Cáceres) (Domingo Rivera, Benigno Cienfuegos and Ángel Luis Sánchez). Two birds at Moheda Alta during January (Luis Lozano and Manuel Gómez Calzado).
- Egyptian Goose: At Charca de Corral Alto, Zorita (Cáceres): 13 birds on 14/01 (Jesús Porras) and six on 29/01 (S. Mayordomo, Pilar Goñi, Pepe Guisado and C. Clemente). One bird at Ruecas Reservoir, Logrosán (Cáceres), on 14/01 (J. Mahillo and C. Clemente). Three birds at La Serena Reservoir (Badajoz) on 18/01 (Xurxo Piñeiro). Nine birds at Navalmoral de la Mata (Cáceres) on 24/01 (Pedro Gómez).
- Shelduck: Two birds at Los Canchales Reservoir (Badajoz) on 5/01 (Elvira del Viejo and Antonia Cangas)and three on 21/01 (Emilio Costillo). Three birds at Brovales Reservoir (Badajoz) on 10/01 and 14/01 (Francisco Montaño). At Valdecañas Reservoir (Cáceres): five birds on 13/01 (Javier Prieta) and four on 24/01 (Ángel Sánchez). At Sierra Brava Reservoir (Cáceres), 32 birds on 14/01 (S. Mayordomo, Marcelino Cardalliaguet, J. Prieta, J. Mahillo, Eva Palacios and C. Clemente) and on 29/01 (S. Mayordomo, P. Goñi, P. Guisado and C. Clemente). One bird at Santa Amalia ricefields (Badajoz) on 18/01 (S. Mayordomo and J. Prieta). Two birds at Cubilar Reservoir (Cáceres) on 29/01 (S. Mayordomo, P. Goñi, P. Guisado and C. Clemente).

- Ruddy Shelduck: Still 4 birds at Portaje Reservoir (Cáceres), seen on 7/01 (S. Mayordomo), 16/01 (S. Mayordomo and Marta Gómez) and 28/01 (S. Mayordomo; photograph).
- Gadwall: 2620 birds on 14/01 at Sierra Brava Reservoir (Cáceres) (J. Prieta and E. Palacios).
- Mallard: 7525 birds on 14/01 at Sierra Brava Reservoir (Cáceres) (J. Prieta and E. Palacios). Leucistic birds: One at Portaje Reservoir (Cáceres) on 16/01 (S. Mayordomo and M. Gómez) and another at Sierra Brava Reservoir (Cáceres) on 29/01 (S. Mayordomo, P. Goñi, P. Guisado and C. Clemente).
- Shoveler: 17,900 birds on 14/01 at Sierra Brava Reservoir (Cáceres) (J. Prieta and E. Palacios).
- Pintail: 13,250 birds on 14/01 at Sierra Brava Reservoir (Cáceres) (J. Prieta and E. Palacios).
- Teal: 15,700 birds on 14/01 at Sierra Brava Reservoir (Cáceres) (J. Prieta and E. Palacios).
- Red-Crested Porchard: Two birds at Llerena-Arroyoconejos Reservoir (Badajoz) on 14/01 (Gustavo Gahete). At Balsa de Moheda Alta, Navalvillar de Pela (Badajoz): one female on 14/01 (S. Mayordomo and M. Cardalliaguet) and two drakes and one female on 29/01 (S. Mayordomo, P. Goñi, P. Guisado and C. Clemente). Eleven birds at Madrigalejo (Cáceres) on 18/01 (D. Rivera, B. Cienfuegos and Á. L. Sánchez). One pair at Morantes Reservoir, Badajoz (Badajoz), on 21/01 (José Luis Bautista).
- Pochard: 104 birds at Manantío-Atalaya gravel pit, Cáceres (Cáceres), on 12/01 (A. Gil). 180 birds at Orellana Reservoir (Badajoz) on 18/01 (D. Rivera, B. Cienfuegos and Á. L. Sánchez).
- Tufted Duck: 41 birds at Horno Tejero Reservoir, Cordobilla de Lácara (Badajoz), on 12/01 (Alberto Gil). 46 birds at Charca de Brozas (Cáceres) on 15/01 (Carlos Fernández). 27 birds at Charca de Corral Alto, Zorita (Cáceres), on 13/01 (J. Porras) and on 29/01 (S. Mayordomo, P. Goñi, P. Guisado and C. Clemente).
- Ferruginous Duck: Four birds at Manantío-Atalaya gravel pit, Cáceres on 12/01 (A. Gil). Two birds at Villalba de los Barros Reservoir (Badajoz) on 17/01 (Lorenzo Alcántara).
- Quail: One bird at Galisteo (Cáceres) on 22/01 (J. Prieta).
- Great Crested Grebe: 665 birds at Alange Reservoir (Badajoz) on 15/01 (L. Alcántara and Jesús Solana). 504 birds at La Serena Reservoir (Badajoz) on 18/01 (X. Piñeiro).
- Black-Necked Grebe: Five birds at Sierra Brava Reservoir (Cáceres) on 10/01 and 51 at Orellana Reservoir on 11/01 (Á. L. Sánchez). Two birds at Charca de Brozas (Cáceres) on 15/01 (C. Fernández). Nine birds at La Serena Reservoir on 18/01 (X. Piñeiro). One bird at Charca de Moheda Alta, Navalvillar de Pela (Badajoz), on 24/01 (Martin Kelsey).
- Glossy Ibis: One bird at Santa Amalia ricefields (Badajoz) on 18/01 (Fernando Yuste). One bird at La Garrovilla gravel pit (Badajoz) on 19/01 (Antonio Horrillo) and possibly the same bird on 21/01 at Montijo Reservoir, Mérida (Badajoz) (J. Solana). Three birds at Moheda Alta, Navalvillar de Pela (Badajoz), on 24/01 (M. Kelsey).

- Bittern: One bird at Valdefuentes gravel pit, Galisteo (Cáceres), on 8/01 (S. Mayordomo). At Arrocampo Reservoir (Cáceres): one bird on 10/01 (S. Mayordomo), on 21/01 (Justiniano Julián) and on 27/01 (Luis Sitges; photograph), and two birds on 28/01 (Unai Fuente).
- Little Bittern: Two birds at River Guadiana, Badajoz, on 17/01 (J. C. Paniagua). At Arrocampo Reservoir: one bird 25/01 (S. Mayordomo) and on 28/01 (Unai Fuente). Two birds at Valdefuentes gravel pit, Galisteo (Cáceres), on 22/01 (S. Mayordomo).
- Night Heron: One bird at Alange Reservoir (Badajoz) on 14/01 (L. Alcántara and J. Solana). At River Guadiana, Mérida (Badajoz), six birds were seen on 21/01 (E. del Viejo and A. Cangas) and then 15 birds in four roosts (J. Solana).
- Squacco Heron: At Arrocampo Reservoir: two birds on 10/01 (S. Mayordomo) and 21/01 (Vicente Risco, J. Julián and Javier Briz). One bird at Brovales Reservoir on 14/01 (F. Montaño). One bird at Logrosán ricefields (Cáceres) on 18/01 (M. Gómez Calzado).
- White Stork: About 1000 birds at Laguna del Palancoso, Navalmoral de la Mata (Cáceres), on 15/01 (V. Risco and J. Briz). 1.071 birds at Riolobos ricefields (Cáceres) on 17/01 (J. Prieta).
- Black Stork: One bird at La Zarza (Badajoz) on 10/01 and another at Cornalvo Reservoir (Badajoz) on 12/01 (J. Solana). Three birds at Charca del Sevillano, Puebla de Alcocer (Badajoz), on 13/01 (Juan Antonio Barquero). On 14/01 one bird at Charca de La Isla, Logrosán (Cáceres) (J. Mahillo and C. Clemente) and another at Cornalvo Reservoir (Badajoz) (J. Solana). Two birds at Navalvillar de Pela (Badajoz) on 18/01 (M. Gómez Calzado). One bird at Monfragüe (Cáceres) on 30/01 (Rafael Abuín).
- Osprey: Five birds at Alqueva Reservoir (Badajoz) on 11/01 (Á. Sánchez). One
bird at Cubilar Reservoir (Cáceres) on 14/01 (J. Mahillo and C. Clemente) and 29/01 (S. Mayordomo, P. Goñi, P. Guisado and C. Clemente). One bird at Dehesa Nueva, Saucedilla (Cáceres), on 15/01 (V. Risco and J. Briz). One bird at Torrejoncillo Reservoir, Pedroso de Acim (Cáceres), on 20/01 (A. Pacheco). One bird at Arrocampo (Cáceres) on 21/01 (J. Julián). One bird at Llerena Reservoir (Badajoz) on 22/01 (V. de Alba and A. Núñez). One bird at Los Canchales Reservoir (Badajoz) on 29/01 (José Antonio Molina).
- Red Kite: Roost with 400 birds at Monesterio (Badajoz) on 8/01 (A. Pacheco).
- Egyptian Vulture: Two birds at Portaje (Cáceres) on 28/01 (S. Mayordomo).
- Imperial Eagle: One bird calling at Villanueva de la Vera (Cáceres) on 28/01; first sighting in the area in ten years (D. Langlois).
- Long-Legged Buzzard: One bird, probably a juvenile light phase, at Almonte River, Santiago del Campo (Cáceres), on 15/01 (Juan José Ramos Encalado).
- Goshawk: One bird at Monfragüe (Cáceres) on 26/01 (A. Pacheco) and on 31/01 (J. Prieta).
- Little Bustard: Flock of 700 birds at La Serena (Badajoz) on 29/01 (Santiago Villa).

- Sandhill Crane: The bird seen in December was sighted again, this time at Hernán Cortés, Don Benito (Badajoz), on 2/01 (J. A. Román; photograph).
- Purple Swamphen: One bird at Miajadas (Cáceres) on 18/01 (Javier Caldera and Á. Sánchez).
- Black-Winged Stilt: 1642 birds at Vegas Altas ricefields (Badajoz) on 18/01 (ECVA)
- Avocet: One bird throughout January at Galisteo lake-ricefield (Cáceres) (S. Mayordomo, M. Gómez and J. Prieta). 37 birds at Palazuelo ricefields (Badajoz) on 14/01 (S. Mayordomo, J. Mahillo, E. Palacios and C. Clemente). 89 birds at Puebla de Alcollarín (Badajoz) on 18/01 (M. Cardalliaguet and Juan Pablo Prieto).
- Grey Plover: One bird at Brozas Reservoir (Cáceres) on 15/01 (C. Fernández).
- Kentish Plover: Ten birds at Palazuelo ricefields (Badajoz) on 14/01 (S. Mayordomo, J. Mahillo, E. Palacio and C. Clemente). 34 birds counted in the area of Vegas Altas (Badajoz) on 18/01 (ECVA). One bird at Alqueva Reservoir, Olivenza (Badajoz), on 21/01 (S. Mayordomo and CTO pupils). 75 birds at Valdecañas Reservoir (Cáceres) on 24/01 (Á. Sánchez). Several birds at Santa Amalia ricefields (Badajoz) on 26/01 (F. Yuste).
- Curlew: Four birds at Santa Amalia ricefields (Badajoz) on 2/01 (F. Yuste). Eight birds at Hernán Cortés (Badajoz) on 10/01 (J. P. Prieto). Two birds at Puebla de Alcollarín (Badajoz) on 18/01 (M. Cardalliaguet and J. P. Prieto). One bird at Galisteo (Cáceres) on 28/01 (S. Mayordomo).
- Black-Tailed Godwit: Over 3000 birds at Santa Amalia ricefields (Badajoz) on 6/01 (F. Yuste). 7369 birds counted on ricefields in the area of Vegas Altas (Badajoz) on 18/01 (ECVA).
- Jack Snipe: One bird at Cañaveral Reservoir (Cáceres) on 11/01 (S. Mayordomo).
- Woodcock: One bird at Valle del Viar, Montemolín-Monesterio (Badajoz), on 8/01 (A. Pacheco).
- Redshank: 133 birds counted in the area of Vegas Altas (Badajoz) on 18/01 (ECVA).
- Spotted Redshank: At Galisteo ricefield (Cáceres): four birds on 2/01 and one on 27/01 (S. Mayordomo). On 13/01 13 birds were seen at Valdecañas Reservoir (Cáceres) (J. Prieta) and one at la Charca Grande de Esparragalejo (Badajoz) (E. del Viejo and A. Cangas). At Vegas Altas (Badajoz) 41 birds were counted on 18/01 (ECVA). Three birds at Charca del Ejido, Villa del Rey (Cáceres), on 23/01 and one bird at Membrío Reservoir (Cáceres) on 25/01 (Helios Dalmau).
- Greenshank: 107 birds in the area of Vegas Altas on 18/01 (ECVA).
- Wood Sandpiper: 2 birds at Zurbarán ricefields (Badajoz) on 18/01 (L. Lozano).
- Ruff: 631 birds in the area of Vegas Altas on 18/01 (ECVA).
- Dunlin: Over 1000 birds at Santa Amalia (Badajoz) on 6/01 (F. Yuste). 3878 birds in the area of Vegas Altas on 18/01 (ECVA).
- Little Stint: 178 birds in the area of Vegas Altas on 18/01 (ECVA).
- Temminck's Stint: One bird at Alqueva Reservoir, Olivenza (Badajoz), on 20/01 (S. Mayordomo).
- Black-Headed Gull: 2000 birds at Alange Reservoir (Badajoz) on 15/01 (L. Alcántara and J. Solana).
- Mediterranean Gull: 3 birds at Los Canchales Reservoir (Badajoz) on 21/01 (Joaquín Fernández and Ángel Sánchez).
- Yellow-Legged Gull: One adult at Valdecañas Reservoir (Cáceres) on 3/01 (S. Mayordomo) and two on 13/01 (J. Prieta). One third-winter bird at Alqueva Reservoir (Badajoz) on 20/01 (S. Mayordomo).
- Lesser Black-Backed Gull: 453 birds at Valdecañas Reservoir (Cáceres) on 13/01 (J. Prieta), 4500 at Alange Reservoir (Badajoz) on 15/01 (L. Alcántara and J. Solana) and 915 birds at Laguna Grande de La Albuera (Badajoz) on 21/01 (S. Mayordomo).


- Short-Eared Owl: Ten birds at Hernán Cortés (Badajoz) on 25/01 (Ricardo Montero). One bird at Santa Amalia (Badajoz) on 29/01 (Á. Sánchez).
- Pallid Swift: Seven birds at Alange (Badajoz) on 10/01 (J. Solana).
- Lesser-Spotted Woodpecker: Sighting in a built-up area: one pair in the city park called Parque del Príncipe, Cáceres (Cáceres), on 8/01 (Juan José Bote).
- Chough: Two birds at Albuera mine, Montemolín (Badajoz), on 8/01 (A. Pacheco).
- Carrion Crow: Six birds at Santa Cruz de Paniagua (Cáceres) on 6/01 (S. Mayordomo).
- Wheatear: One bird at Santa Marta de Magasca (Cáceres) on 12/01 (Merilyn Jewitt and Colin Jewitt).
- Alpine Accentor: Eight birds at the castle of Benquerencia de la Serena (Badajoz) on 28/01 (S. Villa). One bird at Montánchez castle (Cáceres) on 31/01 (M. Kelsey).
- Waxbill: 30 birds in the olive groves/broom scrub of Montehermoso (Cáceres) on 21/01 (J. Mahillo).
- White Wagtail: Subspecies M. a. yarrellii: One bird at El Gordo (Cáceres) on 3/01 (S. Mayordomo). One bird at Los Canchales Reservoir (Badajoz) on 5/01 (E. del Viejo and A. Cangas). On 8/01, one bird at Avarientos gravel pit, another at Valdefuentes gravel pit, Galisteo (Cáceres), (S. Mayordomo), and another at Montijo Reservoir (Badajoz) (F. Montaño). Five birds seen in a roost at Valdefuentes gravel pit on 22/01 and three birds in a recently ploughed field at Galisteo (Cáceres) on 27/01 (S. Mayordomo). During January the bird already recorded in December continued in Plasencia (E. Palacios).
- Bullfinch: Few wintering birds in La Vera this year (D. Langlois). At Santa Cruz de Paniagua (Cáceres): eight birds on 1/01 (Juan Carlos Paniagua) and two on 6/01 (S. Mayordomo). Two birds at Valle del Viar, Montemolín-Monesterio (Badajoz), on 8/01 (A. Pacheco). In Monfragüe (Cáceres): one bird at Corchuelas on 11/01 and two at Huerto del Ojaranzo on 23/01 (S. Mayordomo). Several birds at three sites in La Codosera (Badajoz) on 22/01 (G. Schreur).

EARLY SUMMER VISITORS
- Great Spotted Cuckoo: One bird at La Roca de la Sierra (Badajoz) on 21/12/2011 (Manolo Iglesias). Two birds at Santa Marta de Magasca (Cáceres) on 30/01 (M. Kelsey).
- House Martin: Three birds flocking with Crag Martins at La Zarza (Badajoz) on 10/01 (J. Solana). Two birds at La Codosera (Badajoz) on 19/01 (Godfried Schreur). On 28/01 several birds at Navalmoral de la Mata (Cáceres) (J. Briz). At Monfragüe (Cáceres): one bird on 28/01 (Á. Sánchez) and 40 on 31/01 (J. Prieta).
- Swallow: One bird at Talayuela (Cáceres) on 15/01 (V. Risco and J. Briz). On 22/01, several birds at Los Canchales Reservoir (Badajoz) (E. Costillo) and one at Pago de San Clemente (Cáceres) (M. Kelsey).

SIERRA BRAVA: DUCK COUNTS

Vast rafts of ducks on Sierra Brava Reservoir (Cáceres) on the morning of 14 January 2012.

No, it's not a swarm of mosquitoes or a negative of the Milky Way but several thousand ducks
resting up on part of the reservoir (click to see it larger). By Javier Prieta.

The celebration of World Wetlands Day is as good a time as any to look at one of Extremadura's most outstanding waterfowl sites. Sierra Brava Reservoir lies in the southeast of the province of Cáceres in the catchment area of the River Guadiana, the whole reservoir falling within the municipality of Zorita. It forms part of the irrigation scheme called Central Zone of Extremadura, comprising several reservoirs and a vast area of cropfields, mainly maize, rice and orchards. Built in 1994, Sierra Brava did not become half full until 1998. In January 2002 it was "discovered" by the birding world. In 1995 the traditional wintering wildfowl count fell into disuse in Extremadura so there is no information on the wintering wildfowl of its early years. In January 2002, the recently created GOCE group (Grupo Ornitológico Cacereño, today SEO-Cáceres) decided to re-establish the wildfowl count in Cáceres. Their findings were a huge surprise. No one imagined such a massive concentration of ducks on one reservoir, reckoned to be about 61,000. And Sierra Brava is not alone; other smaller and larger reservoirs of the Central Zone also have huge duck flocks.

Ten years later SEO-Cáceres repeated the wintering wildfowl count in January 2012, aiming to take in the whole of Extremadura. Obviously this time Sierra Brava wasn't to come as such a big surprise. On Saturday 14 six members of SEO-Cáceres set out to census the wetlands of the Central Zone, concentrating on Sierra Brava. Anyone who knows the reservoir will realise that it is impossible to count the birds in situ (see above photo). The chosen method, partially tried out in earlier years, was a mixture of photographic and direct counting. Weather forecasts predicted mist for that day and it even rained on the way there but the morning turned out to be splendid, sunny and windless. This enabled us to make a detailed telescoping scan of the famous rafts of ducks from a nearby high point. For four hours the least numerous species were counted (Greylag Goose, Shelduck, Wigeon and Gadwall), the shores and inlet waters were checked out while also sketching out the proportions of the most abundant species. The fieldwork thus came up with no final result.

The second part of the study came back at home, counting one by one the photographed birds and also indicating species. The working material amounted to 199 photographs and several pages crammed with notes. The photos with fewer ducks were counted on the computer screen, while the more complex photos were printed out in colour. The number of birds per photo ranged from three to 2093 (mean of 252), adding up to 50,187, which turned out to be 86% of the total (58,000). Ascertaining how many corresponded to each species was not as difficult as might be thought since the duck species do tend to flock together on the reservoir. Thus, thanks to 72 field observation points, counting 9703 individual birds (c.20% of the total), one of the great rafts was seen to be formed 99.9% by Shovelers. The figures obtained for this species are reckoned to be accurate. The other big raft was formed almost exclusively by Teal at one end and Pintail at the other, merging in the centre. In most of the photos it proved possible to identify the species, so estimates were made only in doubtful cases in certain parts of the reservoir. Now it remained only to tally these findings with the field counts of scarcer species and zones not visible in the photos (the Mallards occupy above all the outer zones and shores).

Detail of Sierra Brava Reservoir (Cáceres) on 14-01-2012. A total of 1019 ducks has been counted in this image, the immense majority being Teal (Anas crecca) with some Pintail (Anas acuta) in the foreground. By Eva Palacios.

As in other posts of this blog, the idea was to check the previous information published on Sierra Brava and the Central Zone. There is little to go on but we do have the official January counts of Extremadura passed on by SEO/BirdLife to the Environment Ministry. These figures are summed up in the tables below. Unfortunately there is no indication of the methods used, the authors of the count or the dates (some counts seem to have been conducted in February), so we decided to eschew any thorough check. The trend graph shows wild swings; this came as a surprise to us since the many visits paid to Sierra Brava over the last 10 years showed no such thing. It is also surprising to find that some counts give figures of zero Teal or only 140 Shoveler, figures that hardly tally with the real situation. The total Sierra Brava figures, ranging from 11,000 to 102,000 Anatidae, coots and grebes, have been quite controversial for various reasons. At least on two occasions there were simultaneous counts: in 2002 on the same day, throwing up estimates of 45,000 in one case and 73,000 in the other (66% difference; we decided to split this difference); in 2003 the two estimates were similar (about 100,000 birds) but with a very different species breakdown. Despite this, Sierra Brava's importance is unquestionable, accounting as it does for over half of Extremadura's wintering Anatidae on most occasions. If we consider the Central Zone as a whole the area ranks third in Spain for wintering wildfowl, coming behind only Doñana and Ebro Delta.

We don't know if photographic counts were employed on earlier occasions; judging from our 2012 experience, however, it is the method we recommend. Obviously there will be some error but we believe it to be simple and objective. The main limitation might be bad weather with bad light or especially, wind, so the right days do need to be carefully chosen. Coverage also needs to be improved on shores and some of the inlet waters to detect above all Mallards, which might well have been underestimated by this current count.

In case anyone is wondering, we also tried a computer count, using Photoshop, as well as the photographic count. The method works and it proved possible to determine the number of points per photo, but the figures came out 20-30% below the direct count since 2 or more adjacent birds might merge into a single point.

The 2012 count in the Central Zone of Extremadura forms part of the Extremadura Wintering Wildfowl Count brokered by SEO-Cáceres. The most meritworthy work in this endeavour was carried out by Eva Palacios, who patiently took the photos and even more painstakingly counted up the ducks on each one. Javier Prieta completed the fieldwork and came up with the final figures for Sierra Brava. Sergio Mayordomo, Marcelino Cardalliaguet, César Clemente and Javier Mahíllo censused the rest of the Central Zone. Independently, Miguel Ángel Romo and Javier Pérez Gordillo covered the ponds of Manzanares (Campo Lugar, Cáceres). Lastly, our thanks go to Raúl Guzmán for coming up with the alternate computer method and to Blas Molina (SEO/BirdLife) for the figures from the counts of earlier years.

WADERS IN LAS VEGAS ALTAS. JANUARY 2012

On 2 February 1971 the Convention on Wetlands was signed in the Iranian city of Ramsar. Since that date a World Wetlands Day has been held every year on 2 February. Many events have been scheduled in Spain over the coming days. Wetlands are perhaps the habitat most assiduously visited by birders; the waterfowl on show are often striking to the eye, the flocks are sometimes spectacular and rare vagrants are likely to turn up from time to time. Extremadura, rivers apart, is not exactly rich in natural wetlands like marshes or lakes. But in recent years many artificial wetlands have been created by man. This is certainly a controversial subject. Destroying natural habitat to create artificial habitat. A tricky dilemma. We have in fact talked about this contradiction on this blog. Reservoirs are the best known example; ricefields have less of a press, for good or ill. Many foreigners are in fact often surprised to find out that Extremadura is a big rice producer, in some years Spain's biggest. By 2009 there were over 30,000 hectares of ricefield in the region, the bulk of them in the area known as Vegas Altas. Ascertaining their birdlife is no easy task. Last January, however, a coordinated count of Vegas Altas ricefields was organised. To do so the 70,000+ hectares of ricefields were broken down into nine different sectors, each sector being visited on 18 January by one or two people. The joint result of the count was almost 54,000 water birds, pride of place going to waders, whose figures are shown in the following table.

It is worthwhile glossing these figures species by species. The Black-Winged Stilt count was the biggest regional figure ever recorded, multiplying tenfold the mean Extremadura figure in the period 2005-2008 (130 birds). The Little Stint also outnumbered its mean (16 birds). Avocet, Dunlin, Ruff, Curlew and the three little plovers (Ringed, Little-Ringed and Kentish) threw up normal figures. As regards the Black-Tailed Godwit, its pre-breeding migration starts as early as January so the birds seen are not really overwintering. By February the flocks build up to over 25,000 birds (see here). The figures for Lapwing, Golden Plover and Snipe understate the real population because the scattered flocks and birds are hard to count. Lastly, there is little past information to go on in terms of the three "shanks" (Red-, Green- and Spotted) and the three sandpipers (Common-, Green- and Wood) but the figures in general seem to be higher than past records, perhaps due to the wider, though hardly complete, coverage. Two Wood Sandpipers were once again seen, a scarce but regular winter visitor since 2002 in Vegas Altas.

The 2012 waterfowl count in Arrozales de Vegas Altas, part and parcel of the wintering waterfowl count in Extremadura, was organised by Luis Lozano, Juan Pablo Prieto and Fernando Yuste. Other participators were Ángel Sánchez, Atanasio Fernández, Javier Caldera, Domingo Rivera, Manuel Gómez Calzado, Ángel Luis Sánchez, Benigno Cienfuegos, Sergio Mayordomo, Marcelino Cardalliaguet and Javier Prieta.