A LOT OF CRANES ¡¡¡

TRANSLATED BY MARTIN KELSEY

After the successful experience of last winter 2012/2013 (see link) the Extremaduran crane enthusiasts have started a new census programme for the 2013/2014 season. Indeed, this time round, they have succeeded in promoting a national crane census, which took place in December 2013, the results of which have not yet been fully compiled. As a starter, we can provide briefly the figures for Extremadura. The second regional census results from 23-27 January are still pending, which will give us an overall more complete picture. Once the data are ready, we will publish a more detailed posting about the wintering crane population in Extremadura in 2013/2014.

Each cenus brings new record figures for this species. The final result for December 2013 was 128, 820 cranes counted, 29,515 in the provincia de Cáceres-Tajo basin, 82,532 in the Central Zone (see link) and 16,773 in the rest of Badajoz province. It is worth noting that within the Cáceres province census figures there are three roosts with about 7,500 birds that lie inside the territory of Toledo. In the national survey results, they will be treated as such, but given that these counts are undertaken in a coordinated way by observers from Cáceres, at the regional scale they are considered as part of the Extremadura total (as has been the case previously). Indeed, cranes have no borders. Compared with the previous census of December 2012, using the same methodology and similar effort, the result is 29,000 more cranes. In the Tajo basin of Cáceres the population has risen by 8,000 birds, despite the Brozas sector (with 1,500 more cranes) only getting partially surveyed, in the Central Zone there were some 20,000 more, and in Badajoz province about a thousand more cranes.

MORE THAN 100,000 CRANES IN EXTREMADURA (December 2012)

In December 2012 was carried on a common crane (Grus grus) census in Extremadura. As result, 95,282 cranes was counted. The coverage was almost complete, except for the region of La Serena and some roosts of Badajoz province. Estimating 6,000 cranes for no census areas, the final figure reached 101,000 cranes. The breakdown by areas is as follows: Zona Centro 63,207 individuals (62%), 22,292 Tagus basin (22%) and Guadiana basin 15,783 cranes (16%). Since a census of this scope is necessarily incomplete, it is possible that 120,000 cranes were present in Extremadura during winter 2012-2013. If we also consider that in February 2013 200,000 cranes have stopped at Gallocanta lagoon (Aragón), the figure of 120,000 cranes in Extremadura makes sense.

Two different methods have been used, on the one hand the traditional counting roosting, when cranes meet in wetlands to spend the night, and day counts at foraging areas. The latter has been used in the Zona Centro (Vegas Altas), one open agricultural region, with good visibility and extensive road network.

The comparison by sectors over the previous census of December 2007 (Prieta and del Moral, 2008) is shown in the table. For the whole of the region is estimated an increase of 20%. The Zona Centro grows very substantially (+65%), being the sole responsibility of the total increase. The Tagus basin remains very stable (+0'1%), offsetting rising sectors (Alagón and Almonte) those that decrease (Navalmoral and Cáceres). By contrast, the rest of the Guadiana basin, excluding La Serena, shows a drop of nearly 6,000 birds (-23%), mainly in the southern sectors of Alange and Azuaga. However, a census is a still image on a certain date and in the case of the crane wintering numbers can vary greatly between weeks in one place. Thus, after the census presented here, some sectors decreased (the Zona Centro declines slightly to 56,000 birds in January and February 2013), others areas were stable (Alagón) and other increased remarkably (Navalmoral rose by more than 4,000 cranes on February), to give some examples.

The evolution of the common crane population in Extremadura, as shown in the graph, remains positive with continued increases from the first data available in the 1980s. For the first time it has been found a figure of over 100,000 birds in the region, a value that duplicates the censuses conducted two decades ago (about 50,000 birds on average in 1989-1993 and 60,000 in 2001). All in accordance with the increase in Western Europe, where the current population is at least 300,000 cranes.

Sources: 

- Román, J. A. y Gómez Calzado, M. 2013. Invernada de la grulla común (Grus grus). Resultados del censo de diciembre de 2012 en Extremadura. Published on 26-03-2013, blog "Grullas Veo".

- Prieta, J. and Del Moral, J. C. 2008. The common crane wintering in Spain. Population in 2007 and census method. SEO / BirdLife. Madrid. [Download] 

Acknowledgements: This work would not have been possible without the invaluable participation of dozens of people who have dedicated time and effort as volunteers. 

Coordinators: Jose Antonio Roman, Manuel Gómez Calzado and Javier Prieta. Collaborators: Samuel Langlois, Dave Langlois, Manuel Flores, Marcelino Tirado, José María Guerrero, Jorge Pedro Durán, Sergio Méndez, César Clemente, Javier Mahíllo, Goyo Naharro, Agustín Iglesias, Vicente Sánchez, Javier Prieta, Sergio Mayordomo, Iván Hernández, Carlos Fernández Diaz, José Carlos López Fuentes, Marcelino Cardalliaguet, Andrés Maestre, Carlos Luengo, Marta Gómez, Javier Esteban, Martin Kelsey, Jesús Porras, Vicente Risco, Santiago Cáceres, Javier Caballero, José Luis Caballero, Estela Herguido, Antonio Galán, Helios Dalmau, Agustín Martín Ruano, José Antonio Pérez Burón, Daniel Pérez, Luis Venancio, Pedro Schreur, Justo Tarriño, Godfried Schreur, Jacobo Hernández, Jerónimo Milán, Jesús Solana, Francisco Lopo, Elvira del Viejo, Lucas J. Navareño, Carolina Climent, Iván Sánchez, Antonia Cangas, José Antonio Román, José Ángel Sánchez, Luis Salguero, Antonio Núñez, Gustavo Gahete, Francisco Montaño, Miguel Corvillo, Alfonso Pérez del Barco, Esther Gañán, Chema Traverso, Carmen Galán, Yasmina Annichiarico, Natalia Franco, Amparo Sánchez, Agustín Santana, Víctor Manuel Quintana, Manuel Calderón, Teresa Tena, Gerardo Pizarro, Fernando Pizarro, Manuel Gómez Calzado, Antonio Torrijo, Fernando Salas, José Luis Ciudad, Emilio Peña, Marc Gálvez, José Guerra, Fernando Yuste, Juan Pablo Prieto, Manuel Iglesias, Marisa García, Juan Carlos Núñez Crespo, Juan Manuel Rodríguez, Juan Miguel Segador, Gabriel Vidal, Manuel Azabal, Amalia Sánchez, Javier Monforte, José Leonardo Baena, Raúl Calle, Taimar Domínguez, Luis Bernardo Flores, Juan Pablo García, Pablo Hernández, Jorge Jara, Jaime Jiménez, Pablo Jorge Díaz, Alberto León, Mario Martín, Daniel Martín, José Antonio Mateos, David Morón, Antonio Moyano, Abel Murillo, Álvaro Rodríguez, Andrés Rodríguez, Juan Sánchez, Alberto Sánchez, Blas Serrano, Janette Valhondo, Antonio Ávila, Francisco Javier Alba, Juan Gabriel Díaz, Jorge Domínguez Patricio Liberal, Rubén Marcos, Álvaro Martín, David Neila, Valentín Pérez, Carlos Pinos, Juan Carlos Recio Borja Retamal, Ángel Rodríguez, Francis Rodríguez, Cristian Salguero, Juan Marcos Simón, Saúl Torrescusa, Juan Carlos Velarde, Jesús Sánchez, Pedro Muñoz, Jaime Rodríguez, Luis Alberto López, Juan Pablo Resino, Azucena Díaz.

FESTIVAL OF THE CRANES IN EXTREMADURA 2012

The IV Festival of the Cranes will be held this year on Saturday December 1, again at Moheda Alta,Navalvillar de Pela, Badajoz. You can enjoy a day observing nature, with your family or friends, watching the cranes that come from northern Europe and remain here until spring. The final program has no been published yet, but will consist of guided ornithological walks, presentations, folklore and popular food tasting.. For interested parties there are free buses from Cáceres, Badajoz and Meridal to Moheda Alta, returning in the evening.

On Sunday December 2 ADENEX also has, in the same place, the 21st edition of the "Day of the Cranes in Extremadura", starting at 16 h.

More information can be found on the Birding in Extremadura website where the program of activities is published.

HOW MANY CRANES WERE WINTERING IN SPAIN AND EXTREMADURA IN JANUARY 2011?

Quite honestly, we can't really answer this question because we have no formal counts to go on. We can, however, draw on figures from elsewhere to gain some sort of an idea. First of all we should remember that that the last Spanish Crane count (Grus grus) was held in December 2007, thanks to the effort of hundreds of collaborators. The results showed a significant increase in Spain's wintering population, with about 150,000 birds in the whole country and 80,000 in Extremadura. It also showed a tendency for the species to winter further north: Extremadura's share of the national total thus fell from 87% in 1980 to 53% in 2007. Nonetheless, due to the huge overall growth, Extremadura's population grew tenfold in this period (Prieta and Del Moral, 2008).

Coming back to today's situation, we have three main sources of information to gauge the current trend of the western European population. First of all there are the many counts of autumn migration carried out in the region of Central Hesse, Germany. In autumn 2010 no fewer than 210,000 cranes were counted up to 13 December (Kraft, 2010). Yet another all-time high, showing that the population has not yet peaked. Four autumns ago, in 2006, the figure for Hesse was 190,000 birds, with an estimate of 230,000 for the total European population. Simple extrapolation gives a current estimate of about 250,000 birds, one quarter of a million, which is not to be sniffed at. The second source of information comes from the equally numerous winter counts conducted in France (Deschartes, 2011). In January 2011 France clocked up another record figure: 108,000 cranes, topping the 103,000 figure for January 2010 and the 81,600 for January 2009. In 2011 the region of Aquitaine in southwest France accounted for the lion's share, with 66,000 cranes, followed by Champagne-Ardenne (20,200) and central France (15,000). The third source of information comes from Gallocanta Lake in Aragón, Spain, where regular counts are conducted. This year's January count of 18,500 cranes was slightly down on the mean figure of previous years (Heraldo.es).

These three sources of information are pretty much all we have to go on. Bearing in mind, however, that cranes also winter in Portugal, Morocco and Germany, about 130,000 cranes are likely to have wintered in Spain in 2010-2011, somewhat below the figure for 2007-2008 (the French estimate a figure of 124,000 cranes in Spain during the previous winter, January 2010). The dearth of information from Spain, except for Gallocanta and a roost or two elsewhere, rules out any estimate of the population in Extremadura. Nonetheless, everything seems to suggest that it was also down on the 80,000 figure for 2007. Who knows if for the first time in many centuries Extremadura has lost its status as Europe's biggest crane wintering area, losing out to Aquitaine in France? Food for thought: how much have we changed Europe in only two decades for a bird to change its winter range so radically?

Figures apart, another small reflection as the cranes begin to wing north again for spring. The crane spawns all sorts of conferences, festivals and presentations, mainly with a tourism bent. Curiously enough, however, we know very little about the resource we are selling because we don't know exactly how many cranes come here each winter. We can't hope to complete with the industrious French and German and the instant data they are capable of coming up with at the drop of a hat. But it still wouldn't be amiss to conduct at least some sort of joint count in Spain every few years.... Some there are, even on specialist forums, who have asked if cranes still winter in Extremadura (no comment).

Graph. Wintering Common Crane (Grus grus) Trend in France (taken from Dechartes & Le Roy, 2010).

Sources:
- Deschatres, Aurelien. 2011 (Francia). Message in the Forum grus-grus.
- Deschartes, A. & Le Roy, E. 2010. La grue cendrée en France. Migrations et hivernage - Saison 2009-2010 (Migration and Wintering of the Common Crane in France, 2009-2010) [download].
- Kraft, Martin. 2010 (Germany). Message in the Forum grus-grus.
- Heraldo.es (Aragón). 4 Febuary 2011. [read]
- Prieta, J. and Del Moral, J. C. 2008. La grulla común invernante en España. Población en 2007 y método de censo. SEO/BirdLife. Madrid. [download]

THE CRANES ARE HERE

Common Crane (Grus grus). Oliva de Plasencia, Cáceres. 30-08-2010 (J. L. Rivero/Objetivo Verde)

Ever since the end of summer the first winter visitors have been trickling in to Extremadura. This invasion has picked up pace since early October and by now skylarks, meadow pipits, robins, lapwings and red kites are daily sightings just about everywhere. The real red-letter moment of winter arrivals, however, is always the first Common Crane (Grus grus), without doubt one of Extremadura's flagship winter visitors. The first recorded cranes were the 13 seen flying over Trujillo on 9 October (M. Kelsey). But the first real sign of a mass influx was the sudden appearance of 3000 cranes in the Aragón lake of Gallocanta on the 12th, many of which flew off southwards on the morning of the 13th with other groups moving in to replace them (J. Mañas).

They didn't take long to get to Extremadura. On the morning of this same day, the 13th, a flock of 18 was seen in Oliva de Plasencia (R. Montero) and 56 in the central zone (M. Gómez Calzado). On the following days they turned up in many places: 26 over Casas de Miravete (G. Naharro) and 21 in Navas del Madroño on the 14th (G. Schreur and J. Tarriño), 36 on passage over Plasencia (J. Prieta) and 30 in Gabriel y Galán (A. Pacheco) on the 15th, etc. The numbers are now going from strength to strength: by the 14th there were 1200 in the central zone (M. Gómez Calzado), 1000 in Santa Amalia on the 15th (Á. Sánchez) and thousands in Los Canchales on the 16th (A. Matador). In short, an appreciable arrival of birds spread throughout all their traditional wintering areas.

Manolo Gómez Calzado tells us in his blog, dealing almost exclusively with cranes, that their average arrival date in central Extremadura has moved forward about two weeks over the last 20 years. We've checked the Extremadura birdwatching yearbooks to see if the same thing has happened in the region as a whole but no arrival dates were recorded until 2000. From then on, however, the dates have changed little, with the main arrival around 15 October and a few forerunners in the last days of September. It is sad to note that until recently there was so little interest in recording and communicating such a striking event.

These checks of the yearbooks from 1998-2008 did have a serendipitous result, however. They served to confirm that there were no previous records of cranes oversummering in Extremadura, something that has in fact occurred in various sites in 2010. One example has already been mentioned on several occasions in this blog (sightings of June and August): a 2nd-year bird present in Oliva de Plasencia at least from 12 June to early October and seen by numerous birdwatchers (R. Montero, S. Mayordomo, J. Prieta, J. L. Rivero, E. Palacios, J. C. Paniagua, et al; top photo). Another was seen on 22 June in the reservoir of Los Canchales (T. Álvarez in Quercus 294:47), where it was still around on 18 September (Á. Sánchez). And apparently another two cranes oversummered around the reservoir of Orellana (M. Gómez Calzado) and three more in Gallocanta, Aragón (J. Mañas). In previous years there were records of cranes in Extremadura in spring and summer, at times until August, never in September. It was always mooted that these were sick birds unable to migrate. But we can confirm here that the first two abovementioned birds in summer 2010 seemed to be in perfect nick.