Monday, 23 August 2010

THE GOLDEN EAGLE IN EXTREMADURA (2008)

In 2008 SEO/BirdLife promoted the 2nd National Golden Eagle Census (Aquila chrysaetos). A total of 123 pairs were found in Extremadura, although 14 of these are only probable. The shareout between Extremadura's 2 provinces is pretty even, with 65 pairs (6 probable) in Cáceres and 58 (8 probable) in Badajoz. Although the coverage was good, the census may well understate the actual Golden Eagle population. These figures mean that the region has middling importance on a national scale, ranking fifth with 7% of the total census of 1553-1769 pairs. Broken down by provinces, Cáceres and Badajoz come 8th and 13th, respectively, with densities similar to the national mean of 0.35 pairs per 100 km2 (density of 0.3 pairs per 100 km2 in Extremadura, 0.33 in Cáceres and 0.27 in Badajoz).

The Golden Eagle occupies much of Extremadura's territory; it is missing only from the plains of the rivers Guadiana, Alagón and Tiétar and almost the whole of southwest Badajoz. In Cáceres it breeds in the districts of Gata-Hurdes (3 pairs), Gredos (7), SPA Canchos de Ramiro (2), southwest of the province from Tajo internacional to Sierra de San Pedro (15), Monfragüe and the surrounding area (18, six in Monfragüe itself), Ibores-Villuercas (17) and Montáchez-Trujillo (3). In Badajoz it breeds in the Sierra de San Pedro (4 pairs), La Siberia (11), La Serena (14), Campiña Sur (9), central sierras (10), Sierra Morena-Tentudía (10) and the south western corner (one isolated pair).
Although most pairs are rock nesters, 24% did nest in trees in 2008, using the following tree species: Holm Oak (13 pairs), Cork Oak (9), Maritime Pine (4) and Eucalyptus (2). At least one Gall-Oak nest is known from previous years. The proportion of tree nests is higher in Badajoz (27%) than in Cáceres (18%), with a similar breakdown of tree species. The sectors with most tree nesters were the area between Monfragüe and Llanos de Cáceres (9 pairs), Tentudía (7) and Campiña sur (5); there were also tree nests in Sierra de San Pedro (3), La Siberia (2), Villuercas (1) and Trujillo (1).

No detailed breeding information is to hand, although it is known that at least 73 pairs laid eggs and 58 pairs bred successfully (79%). Figures from 2020 point to a productivity of 0.83 young per breeding pair, similar to the national mean in 2008 of 0.8.

The published figures indicate a steady upward trend with an observed growth rate of 35% in 20 years. The trend is similar in Spain as a whole, with an observed growth rate of 40% and estimated growth rate of 20%. Broken down by periods, from 1988 to 1994 the observed increase in Extremadura was 16%; the period 1994 to 2002 clocked up a similar 17% growth rate, although 10% came in only two years (2000 to 2002); lastly, numbers apparently held steady from 2002 to 2008. Part of the increase can almost certainly be put down to better surveying than a real increase in the bird's population. This supposition is borne out by two factors: firstly, the fact that the sharpest increase came in a period of only two years and, secondly, the higher proportion in recent years of tree nesters (trees nests are harder to find and were probably overlooked in earlier counts). In general many of the traditional nest sites repeat from one census to another, though there are known cases of abandoned territories and occupation of new ones, some in flat almost treeless areas. Given that the objective and subjective factors of this apparent increase cannot really be disentangled, the most prudent conclusion is to assume that the Golden Eagle is holding steady in Extremadura.

The 2008 Extremadura Golden Eagle Census was carried out by the Dirección General del Medio Natural (Environment Board) of the Junta de Extremadura (Regional Council of Extremadura) with subsequent grafting on of information from SEO-Cáceres.

Sources:
Prieta, J. 2009. El águila real en Extremadura. Pp. 107-110.
Prieta, J. 2009. El águila real en Badajoz. Pp. 111-112.
Prieta, J. 2009. El águila real en Cáceres. Pp. 112-114.
In: Del Moral, J. C. (Ed). 2009. El águila real en España. Población reproductora en 2008 y método de censo. SEO/BirdLife. Madrid

Friday, 20 August 2010

THE EGYPTIAN VULTURE IN EXTREMADURA (2008)

In 2008 SEO/BirdLife promoted the 3rd National Egyptian Vulture Census (Neophron percnopterus). A total of 179 pairs were found in Extremadura, although 12 are rated as only probable breeders. The shareout between Extremadura's two provinces is very uneven, Cáceres weighing in with 80% (143 pairs; 12 probable) and Badajoz with the remaining 20% (36 pairs). Although the coverage was good, the census probably understates the real population due to the difficulty of censusing the species (it is calculated that 3 visits per territory will detect only 75% of the population). These figures mean that the region ranks third in importance nationwide, behind Castilla y León and Aragón, accounting for 11.5% of the 1452-1556 pairs found in the nationwide census. Broken down by provinces, Cáceres boasts the country's biggest Egyptian Vulture population, ahead of Huesca and Navarre; while Badajoz ranks in a modest 18th place nationwide. The mean regional density was 0.42 pairs per 100 km2, well above the national mean density of 0.3). Cáceres recorded a much higher density (0.79) than Badajoz (0.16).

The Egyptian Vulture has an ample range throughout the province of Cáceres; it is missing only in flat areas (river plains of Alagón and Tiétar, Llanos de Brozas, Cáceres, Trujillo y Zorita) and some mountainous areas such as the Sierra de Gata. In the northern third of the province there are three small clusters: Las Hurdes (2 pairs), Alagón medio (3) and Gredos (7). The rest of the territory is occupied fairly evenly: centre-east, in the final half of Alcántara reservoir, including Canchos de Ramiro (19 pairs); Monfragüe (34); the area southwest of Monfragüe, between Cañaveral and the rivers Almonte and Tamuja (9); southwest of the province, taking in the Tajo Internacional, Sierra de San Mamede and the rivers Aurela and Salor (30); Sierra de San Pedro (12); Ibores and Villuercas (25) and three isolated pairs in Montánchez, Llanos de Cáceres and Trujillo. Particularly worthy of note is the high density recorded in Monfragüe, Tajo internacional and Canchos de Ramiro. The species is scarcer and more local in the province of Badajoz, where it breeds in La Siberia (10 pairs), La Serena (11), central sierras (6) and Alburquerque-Sierra de San Pedro (9). Broadly speaking the Egyptian Vulture is a rock nester on cliffs and crags in extensive livestock rearing areas. Curiously enough, however, this census unearthed one Cáceres pair of Egyptian Vulture breeding in a White Stork's nest in a Stone Pine (Pinus pinea). This was apparently the only tree nest in Spain in 2008, although there are past records of two pairs breeding on Holm Oak and Pyrenean Oak in 1990 in Salamanca.

There is little to go on in terms of breeding performance. In the province of Cáceres 81 pairs began incubation with a failure rate thereafter of 18% (15 pairs). Likewise, a sample of 34 nests with initiated breeding in Monfragüe and Tajo Internacional shows a breeding success rate of 1.03 young per pair that began breeding and a fledgling rate of 1.25. Both figures were the best recorded in Spain in 2008, well above the respective national means of 0.88 and 1.03. They should be taken with some caution, however, in default of any detailed information about the monitoring procedure.

The published figures suggest that the Egyptian Vulture in Extremadura is recording a steadily upward trend. Each census has always recorded higher figures than the previous one. The 50% increase recorded from 1987 (108 pairs) to 1992 (151 pairs) is due mainly to increased efficiency of the census. In the eight year period running from 1992 to 2000 the population increased by 13% up to 170 pairs; in the next eight year period, running from 2000 to 2008, the growth rate was 5%, increasing to 179 pairs. Given that it is impossible to ascertain how far this increase is due to a better knowledge of the species, the most prudent conclusion to draw is that the Egyptian Vulture is holding steady in Extremadura.
Between the censuses of 2000 and 2008, 42 territories were apparently abandoned while 61 new ones were taken up. These are very high figures that do not tally with the findings of other better studied areas; they could therefore be due to differences in criteria and quality from one census to another. At provincial level the situation seems to be better in Cáceres, where a certain growth is observed, than in Badajoz where the population seems to be stable. On a smaller scale, local differences are observed within the general scenario of ongoing stability, with a continuation of the abovementioned pre-2000 trend of abandoned territories in peripheral areas and new territories taken up in areas of lower density. Such are the cases of Monfragüe, Tajo Internacional and Villuercas, where real increases are recorded; conversely, declines have been observed in northern Cáceres or La Siberia in Badajoz. It should be pointed out here that cases of poisoning have been discovered in the latter district, and this may well be behind the specie's decline.

The 2008 Extremadura Egyptian-Vulture census was carried out by the Dirección General del Medio Natural (Environment Board) of the Junta de Extremadura (Regional Council of Extremadura), with subsequent addition of information from SEO-Cáceres.

Sources:
Prieta, J. 2009. El alimoche común en Extremadura. Pp. 106-109.
Prieta, J. 2009. El alimoche común en Badajoz. Pp. 109-111.
Prieta, J. 2009. El alimoche común en Cáceres. Pp. 111-114.
In:
Del Moral, J. C. (Ed). 2009. El alimoche común en España. Población reproductora en 2008 y método de censo. SEO/BirdLife. Madrid.

Monday, 9 August 2010

JULY 2010: Notable bird sightings in Extremadura

List drawn up by Sergio Mayordomo showing the most interesting records sent to the GOCE forum in July 2010. Unless otherwise stated the province involved is Cáceres. Photo: Purple Glossy Starling (Lamprotornis purpureus), Almendralejo (Badajoz). Photographer: Antonio Matador.

-Red-Backed Shrike: 1 male, 2 females and 8 juveniles at Puerto de Tornavacas on 31/07; one of the juveniles was within the territory of Cáceres (Eva Palacios and Sergio Mayordomo)
-Collared Pratincole: Over 40 birds on 20/07 at Casas de Hitos, Madrigalejo (Martin Kelsey) -Little Ringed Plover: Noteworthy sighting of over 370 birds at Casas de Hitos, Madrigalejo, on 20/07 (Martin Kelsey).
-Kentish Plover: 4 birds at Casas de Hitos, Madrigalejo, on 20/07 (Martin Kelsey).
-Black Winged Stilt: Noteworthy sighting of over 350 birds at Casas de Hitos, Madrigalejo, on 20/07 (Martin Kelsey).
-Cuckoo: A free-flying juvenile being fed by a Corn Bunting at Barquilla de Pinares, Talayuela, on 25/07 (Dave Langlois).
-Spoonbill: Noteworthy sighting of 46 birds at Charco Salado, Casatejada, on 19/07 and 32 birds on 26/07 (Sergio Mayordomo).
-Purple Glossy Starling (Lamprotornis purpureus): One bird at Almendralejo, Badajoz, on 16/07; this bird has been seen in the area since 2009 (Antonio Matador).
-Squacco Heron: One bird at Valdeobispo Lake on 11/07 (Eva Palacios and Sergio Mayordomo).
-Peregrine Falcon: One pair at Monesterio, Badajoz, on 12/07, the first known territory in southern Badajoz (Alberto Pacheco).
-Night Heron: Possible breeding in Portaje Reservoir, where two juveniles, two adults and one second-year bird were seen by Eva Palacios and Sergio Mayordomo between 9 and 23/07.
-Dipper: One bird at Garganta de San Martín, Tornavacas, at a height of about 1500 m.a.s.l. on 31/07 (Eva Palacios and Sergio Mayordomo).
-Bluethroat: One bird in breeding territory at Collado del Herido, Tornavacas, on 31/07 (Eva Palacios and Sergio Mayordomo).
-Black-Necked Grebe: One bird at Sierra Brava Reservoir, Zorita, on 20/07 (Martin Kelsey).
-Whimbrel: One bird at Casas de Hitos, Madrigalejo, on 20/07 (Martin Kelsey).

First post-breeding record:
-Snipe: One bird at Galisteo lake on 22/07 (Sergio Mayordomo).
-Wood Sandpiper: One bird at Galisteo lake on 08/07 (Javier Prieta and Sergio Mayordomo). 10 birds at Casas de Hitos, Madrigalejo, on 20/07 (Martin Kelsey).
-Common Sandpiper: One bird at Fresnedillas pond, Oliva de Plasencia, on 05/07 (Sergio Mayordomo)
-Greenshank: 26 passage migrants at Galisteo Lake on 08/07 (Sergio Mayordomo).
-Redshank: 15 birds at Casas de Hitos, Madrigalejo, on 20/07 (Martin Kelsey).
-Spotted Redshank: At Charco Salado, Casatejada: 2 birds on 19/07 and 5 birds on 26/07 (Sergio Mayordomo).
-Garganey: Two birds on Galisteo Lake on 16/07 and one bird on 22/07 (Sergio Mayordomo).
-Teal: 6 birds at Charco Salado, Casatejada, on 26/07 (Sergio Mayordomo).
-Ringed Plover: One bird at Casas de Hitos, Madrigalejo, on 20/07 (Martin Kelsey).
-Ruff: Over 40 birds at Casas de Hitos, Madrigalejo, on 20/07 (Martin Kelsey).
-Dunlin: 4 birds at Casas de Hitos, Madrigalejo, on 20/07 (Martin Kelsey) and 2 birds at Valdesalor Reservoir, Cáceres, on 24/07 (Carlos Fernández).
-Shoveler: One female at Galisteo Lake on 02/07 (Sergio Mayordomo) and one female and 2 drakes on 03/07 (César Clemente and Javier Mahillo).
-Lesser Black Backed Gull: In Badajoz on 24/07: 4 at Azud del Guadiana and 50 at Puente Viejo (Juan Carlos Paniagua).

Tuesday, 13 July 2010

JUNE 2010: Notable bird sightings in Extremadura

Pato colorado (Netta rufina). Macho nupcial. Por Javier Prieta.

-Red-Backed Shrike: One male at Puerto de Tornavacas, Ávila, on the border with Cáceres, on 06/06 (Dave and Sammy Langlois)
-Green Sandpiper: First post-breeding dispersal observations, 9 birds in Galisteo ricefields and 2 in Galisteo lake on 15/06 (Sergio Mayordomo)
-Lapwing: First post-breeding dispersal observations, 3 birds in Galisteo ricefields on 15/06 (Sergio Mayordomo)
- Rüppell's Griffon : One immature at Salto del Gitano, Monfragüe, on 5/06 and 6/06 (Jesús Porras, Ernest García, Manolo García del Rey, Sergio Mayordomo et al)
-Long-Legged Buzzard: One second-year bird in Llanos de Belén, Trujillo, on 11/06 (Ernest García), and other or the same bird on 22/06 in Los Cerralbos, Trujillo (Martin Kelsey)
-Spoonbill: 12 birds on the lakes of La Albuera, Badajoz, on 22 and 27/06 (Juan Carlos Paniagua)
-Whiskered Tern: At least 10 birds on the lakes of La Albuera, Badajoz, on 22/06 (Juan Carlos Paniagua)
-Egyptian Goose: One bird on 16/06 in a livestock pool in Parque Natural de Cornalvo, Badajoz (José Ledo)
-Black-Headed Gull: First post-breeding dispersal observation in Galisteo ricefield on 04/06 (Sergio Mayordomo)
-Crane: One over-summering bird in Oliva de Plasencia on 12/06 and 18/06 (Ricardo Montero)
-Red-Crested Pochard: 2 drakes at Arrocampo reservoir on 20/06 (César Clemente)
-Rock Thrush: 2 males at the mountain pass of Castilla, Gata, at about 1100 masl on 13/06 (Sergio Mayordomo)

Tuesday, 6 July 2010

SPANISH IMPERIAL EAGLE. DOWNWARD TREND IN EXTREMADURA?

We have just received the results of the Environment Ministry's 2009 Spanish Imperial Eagle census (Aquila adalberti). These figures have not yet been cross checked against official sources so they should probably be taken with a pinch of salt.

It is promising to see that the Spanish population of this threatened raptor, which is just about the worldwide population, put in a good showing again this year. The following graph shows this upward trend, with 12 new breeding pairs and a doubling of the figures from only 10 years ago (from 133 pairs in 1999 to 261 in 2009).

On the other hand we are saddened to see Extremadura bucking this bright trend, with a 16% downturn, 8 pairs fewer, in only two years. No other region has seen a reduction in any year of the last decade; Extremadura has now plunged from the region with most Imperial Eagles to last place.

It would now be enlightening if the authority responsible for the conservation of this species gave more information to bear out or rebut these figures. This is unlikely to happen, however, since little or no information is given on the monitoring of threatened species, despite the general interest. Little or nothing was said about the sudden increase from 40 to 49 pairs in two years and we have no idea how it came about. Now we know just as little about this decline or its causes. At least census figures are forthcoming for Monfragüe, showing that the population has held steady at 12 pairs in recent years.

The following table shows the complete breakdown by region from 1999 to 2009. The figures have been taken from the Environment Ministry (figures sometimes differ from one source to another so this one source was chosen for the sake of consistency). Figures are also available from other sources in other regions: Castilla y León (with a detailed map), Castilla-La Mancha (there is a magnificent book and an article about Toledo in Ardeola) and Andalucía (with excellent official information in internet on the monitoring of threatened species). Unfortunately there is nothing similar in Extremadura, despite the existence of a website for this purpose and the public funds pumped into the much vaunted "information society".

Wednesday, 16 June 2010

MAY 2010: Notable bird sightings in Extremadura

A list is given below of the most interesting records sent to the GOCE forum in May 2010. Our intention is to publish monthly summaries from now on. The merit of compiling and selecting the records is due to Sergio Mayordomo and the photo, a Honey Buzzard, is by Sammy Langlois.

- Honey Buzzard: First sighting on 02/05 in Plasencia (Jenny and Michel Viskens)
- Osprey: One in Arrocampo reservoir on 04/05 (Godfried Schreur) and another in Zarza la Mayor reservoir on 22/05 (Javier Mahillo)
- Bar-Tailed Godwit: two birds in Portaje reservoir on 07/05 (Sergio Mayordomo)
- Hobby: First sighting on 04/05 in Arrocampo reservoir(Godfried Schreur)
- Lesser Kestrel: New breeding colony, at least two pairs in Tejeda del Tiétar (Javier Prieta)
- Golden Plover: One very late bird seen on 11/05 in Campo Lugar (E. Barnes and P. Barnes)
- Grey Plover: Four birds in breeding plumage in Portaje reservoir on 7/05 and 16/05 (Sergio Mayordomo).
- Dunlin: Last observation of three birds in breeding plumage in Portaje reservoir on 16/05 (Sergio Mayordomo)
- Garden Warbler: One on 20/05 in Villanueva de la Vera (Dave Langlois).
- Spoonbill: late passage of 13 birds in Galisteo lake on 15/05 (Sergio Mayordomo)
- Little Egret: New breeding colony in Portaje reservoir (César Clemente, Javier Mahillo and Sergio Mayordomo)
- Great White Egret: 11 birds in flight over Villanueva de la Vera on 12/05 (Dave Langlois)
- Cattle Egret: New breeding in Portaje reservoir(César Clemente, Javier Mahillo and Sergio Mayordomo)
- Penduline Tit: Confirmed breeding along River Jerte in Plasencia, at least two nests with young (Javier Prieta, Ricardo Montero and Sergio Mayordomo)
- Tufted Duck: One pair on 28/05 in Charca de Juana Morena, Talaván (Sergio Mayordomo)
- Wryneck: Possible breeding in Plasencia, at least two pairs (Ricardo Montero and Javier Prieta) and in Villanueva de la Vera (Dave Langlois)
- White-Rumped Swift: first sightings on 25/04, one bird in Portilla del Tiétar and another in Salto del Gitano, Monfragüe (Martin Kelsey)
- Pied-Billed Grebe: one in Huertas de la Magdalena, Trujillo, on 13/05 (Nigel Milbourne, John Barnet, Jack Willmott, Pete Massey and Jesús Porras), 14/05 (Pieter Vantieghem) and 15/05 (Nigel Milbourne).

Monday, 7 June 2010

A RÜPPELL’S VULTURE IN MONFRAGÜE

The normal range of the Rüppell’s vulture(Gyps rueppellii), also known as Ruppell’s Griffon or Rueppell’s Vulture, takes in Subsaharan Africa, north of the equator from Guinea to Tanzania. It is catalogued worldwide as Near Threatened due to its recent decline. It is considered to be a rarity in Spain with only 31 sightings involving at least 43 birds accepted by SEO’s Rarities Committee up to 2007. Most were seen in Andalucía, especially near the Straits, and further inland. In Extremadura it has been spotted on several occasions although only three records have been officially accepted: one bird in May and June 1992 in Valencia de Alcántara and Santiago de Alcántara, an immature bird in Oliva de Mérida in May 2000 and an adult in June 2004, again in Valencia de Alcántara. Other claimed sightings since 1990 were not accepted. As for Monfragüe there is only one sighting pending acceptance, of an immature seen at the Portilla del Tiétar in May 2008, backed up by on-the-spot photos.

Another immature Rüppell’s has now turned up in Extremadura, observed on 5 and 6 June 2010 in the famous birdwatching spot called Salto del Gitano in Monfragüe. As part of the "Aves en vivo y en directo" (Birds live and on the spot) programme, SEO/BirdLife have been running a weekend and holiday information stand on this spot from 13 March to 6 June 2010, patiently manned by Sergio Mayordomo and Manuel García del Rey. On the morning of 5 June a local guide called Jesús Porras spotted the Rüppell’s Vulture in flight from the lookout point, whereupon it was also seen by the other people present at the time. Ernest García, ex-member of SEO’s rarities committee, happened to be in the area that weekend and also saw the bird on Saturday afternoon and Sunday morning, duly confirming the identification. The photos at the start and end of this blog entry clearly show an immature Rüppell’s Vulture, possibly a juvenile born in 2009 making its first moult. This therefore represents the fifth Extremadura record, all in the months of May and June, at which time immature birds in post-breeding dispersal probably join up with flocks of Griffon Vultures wintering in Africa and return with them to Europe in spring. Nonetheless, adult birds have also been recorded on the border between Cáceres and Portugal, including a bird sitting on a nest in 1998 on the Portuguese side of the border.