Tuesday 31 August 2010

FIRST BREEDING RECORD OF GREAT WHITE EGRET IN EXTREMADURA

Great White Egret (Egretta alba), adult in breeding plumage. Arrocampo Reservoir, Cáceres. 12.05.10 (Javier Prieta)

The Great White Egret (Egretta alba) has at last been proven to breed in Extremadura. Inevitably, the site of this long-expected event was Arrocampo Reservoir (Cáceres), where eight species of heron now breed (Grey Heron, Purple Heron, Little Egret, Great White Egret, Cattle Egret, Squacco Heron, Night Heron and Little Bittern), a ninth regularly winters (Bittern) and a tenth has been seen on a few occasions (a presumed hybrid between Little Egret and Western Reef Egret). Numbers of Great White Egret in Arrocampo have steadily built up over the last decade, with a notable roost of 25-30 birds in winter 2009-2010, the biggest flock ever recorded in Extremadura (D. Langlois and S. Langlois, personal observation).

Great White Egrets in breeding plumage have been observed each spring in Arrocampo since 2006, sometimes up to three at once. It is therefore quite on the cards that the species has been breeding there unbeknown to anyone for several years. The breeding has finally been proven by Javier Prieta (JP), Sergio Mayordomo (SM) and Eva Palacios (EP). Suspicions first arose on 12 May 2010 when a bird in breeding plumage seemed to have taken up residence in a reedmace bed (top photo) with another bird in breeding plumage seen elsewhere in the reservoir (JP). On 23 May these suspicions were confirmed when a pair of birds in breeding plumage were seen flying in with nesting material (SM and EP, bottom photo). On successive visits in June and July the pair was again seen winging in and out of the suspected nesting site, impossible to see among the thick vegetation (JP and SM). The site was last visited on 5 August, with few other heron species left in the reservoir and little hope of proving anything either way (JP). But the pair of Great White Egret, with lingering traces of breeding plumage, were still there. They flew in to feed the invisible and clearly audible young several times. The begging calls of the young suggested that at least two were involved. Then came the key moment: for just a couple of seconds a Great White Egret flew up from the nest and landed in a visible site after two short flights. It was a young bird: the first one ever to take wing in Extremadura.

Great White Egret (Egretta alba), adult in breeding plumage carrying nesting material. Arrocampo Reservoir, Cáceres. 23.05.10 (Eva Palacios).

The Great White Egret is a species in clear expansion throughout Western Europe. It was present on the Iberian Peninsula in the nineteenth century but there were no known records from 1894 to 1965 (de Juana and Ferrer, 1996). Breeding in Spain was first confirmed in the Ebro Delta in 1997, where it has been nesting regularly in increasing numbers since 2000 (Fouce, 2003). It has also bred at least in Doñana (in 1998; Fouce, 2003), in Albufera de Valencia (breeding attempt in 2000; Fouce, 2003), in Toledo (three nests in Azután Reservoir in 2009; de la Cruz et al. 2009) and in Huesca (one successful nest in Sariñena lake in 2010). In Extremadura, the species had been seen only 6 times by 1995 and regular sightings did not begin until 1997, with a steadily upward trend thereafter (top graph; Prieta 2007). After 2004 the number of sightings added up to well over one hundred a year and the bird ceased to be a species for which all sightings were recorded. Also from 2004 onwards flocks of over 10 birds were observed in Arrocampo and the Caceres part of Tiétar Valley (15 in 2004, 16 in 2007 and 24 in 2009; J. Prieta and S. Mayordomo, unpublished record). Taken together these two sites make up the best area for the species in Extremadura.

References:
- De Juana, E. and Ferrer, X. 1996. El estatus de la garceta grande (Egretta alba) en la península Ibérica y las islas Baleares. Ardeola 43:225-229.
- De la Cruz, J.; M. A. de la Cruz, A. de la Cruz, A. Herrero and L. Herrero/SEO-Talavera y Ardeidas. 2009. Garceta grande Egretta alba. Noticiario ornitológico. Ardeola 56:156.
- Fouce, V. 2003. Garceta grande Egretta alba. En: Martí, R., and del Moral, J. C. Atlas de las aves reproductoras de España, p. 610. SEO/BirdLife. Madrid.
- Prieta, 2007. Aves de Extremadura vol. 3, 2001-2003. ADENEX. Mérida.

Friday 27 August 2010

PEREGRINE FALCON IN EXTREMADURA (2008)

In 2008 SEO/BirdLife brokered a national Peregrine Falcon (Falco peregrinus) census. The census fell short of the overall objective, however, with nil or partial counts in 18 of Spain's provinces. Extremadura was one of the regions where the census was partial, coming up with a figure of 44 occupied territories, 7 of them rated as only probable. This is a bottom-line figure because the actual population is bound to be greater, though it is very difficult to pinpoint by how much; maybe the real figure is over 60-65 pairs. Almost the whole known population is in Cáceres (42 pairs, 95%; more than 55 estimated); Badajoz accounts for only two pairs (5-10 estimated). This makes Extremadura the nation's second least important region ahead of only Madrid, containing 1.6% of Spain's 2462 to 2804 pairs. By provinces, Cáceres ranks 25th, while Badajoz comes in last together with Seville. The density is the country's lowest, with only 0.11 territories per 100 km2, way below the national mean density of 0.56.

The Peregrine Falcon breeds in all Spain's provinces, recording its highest density in the Canary and Balearic archipelagos and the Canabrian and Mediterranean coastline. Inland the most important areas are the Cantabrian, Pyrenean and Iberian mountain ranges. In Extremadura its range takes in the mountain ranges of the north and east of Caceres, with scattered presence in the centre of Cáceres and northeast Badajoz. The most important areas are Ibores-Villuercas (17 pairs), Valle del Jerte (8), Las Hurdes (7) and Monfragüe (4), with odd breeding pairs in the Sierra de Gata (2), Valle del Alagón (2), La Vera (2), La Serena (1) and La Siberia (1). There are nonetheless thought to be several more pairs in the Sierra de Gata (1-2), Valle del Ambroz (2), La Vera (1) and Villuercas (3). In 1998-2002 its presence was recorded in sites with nil counts in 2008, such as the Sierra de San Pedro (4 pairs) and scattered points of the centre and south of Cáceres and the centre and east of Badajoz. In Extremadura, therefore, it can be said to favour areas of a higher altitude and less of a Mediterranean influence. Particular notable is its absence in the southern thirds of both provinces, a lacuna stretching to Huelva, Seville, Córdoba and the meseta sur (Southern Tableland). The reasons for this seem to be lack of nesting sites and competition with other raptors like the Eagle Owl (Bubo bubo).

In 2008 all Extremadura's Peregrine were ledge nesters. Most of these cliffs were quartzite, although nests are also built on granite cliff ledges in the Sistema Central (Central Mountain Ranges), with rarer recourse to rocks of slate and other material. There are no known nests on artificial structures (accounting for 4.3% of Peregrine nests nationwide), including power line pylons (2.8% in Spain, used especially in Valladolid and, to a lesser extent, in León, Córdoba et al). Curiously enough there was one tree-nesting pair in 2008, in Seville, using an old Black Kite's pinetree nest (there are other records of tree nests in Ávila). There are a score of nests in built-up areas in Spain as a whole but none in Extremadura; in any case many of these urban breeders are actually the result of reintroduction projects.

There is very little to go on in terms of the Peregrine's breeding performance in Extremadura, although 10 out of the 12 pairs that are known to have begun incubation in 2008 actually ended up breeding successfully (83%). There is also a recorded productivity figure of 1.79 young per pair in 2002, above the Spanish mean of 1.42 in 2008 and similar to the 1.74 figure of Andalucía and the 1.8 of Castilla-La Mancha.

The fact that no complete counts have ever been conducted in Extremadura makes it hard to ascertain the regional trend of the Peregrine Falcon. Partial information is available for the years 2000 (38-44 pairs), 2002 (49-60) and 2007 (50). The graph shows the maximum figures known in these years rather than the real population trend. Nonetheless, judging from the highest-density and best-surveyed areas, the trend seems to be stable, with traditional territories regularly occupied and few known cases of abandoned territories. Thus, the figures for these areas in the years 2000, 2002 and 2008, were, respectively 9, 8 and 9 pairs in Gata-Hurdes; 6, 10 and 10 in Gredos and 14, 18 and 17 in Ibores-Villuercas. Nonetheless the Peregrine's numbers are falling in nearly all the provinces bordering on Extremadura (Salamanca, Ávila, Toledo, Córdoba and Sevilla), especially in river valleys (only one territory remains in the Adaja valley in Ávila; the number of pairs along the Tagus as it runs through Toledo have fallen from 30 to 2 pairs and similar cases are recorded for Guadalajara and Madrid) and in western Sierra Morena (where it no longer breeds). Several reasons are put forward for this decline, though mention is always made of the Eagle Owl as competitor for nesting sites and predator of adult and young Peregrines. Closer attention will therefore have to be paid to Extremadura's population to pinpoint any possible decline.

Most of the figures on Peregrine Falcon in Extremadura in 2008 were furnished by the Dirección General del Medio Natural (Environment Board) of the Junta de Extremadura (Regional Council of Extremadura), with subsequent phasing in of additional information from SEO-Cáceres. The photographer is J. M. Domínguez Robledo.

Sources:
Prieta, J. 2009. El halcón peregrino en Extremadura. Pp. 115-118.
Prieta, J. 2009. El halcón peregrino en Badajoz. Pp. 118-119.
Prieta, J. 2009. El halcón peregrino en Cáceres. Pp. 119-120.
En: Del Moral, J. C. (Ed). 2009. El halcón peregrino en España. Población reproductora en 2008 y método de censo. SEO/BirdLife. Madrid.


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).