Monday, 1 April 2013
GREYLAG GOOSE IN EXTREMADURA. JANUARY 2013
The 2012-2013 winter has come to an end and it is time to talk about the wintering birds in Extremadura. There are many who are interested after waterfowl, crane and cormorant censuses. I think its a good idea to start with the wintering greylag goose (Anser anser). The census of January 2013 recorded 23,173 individuals in Extremadura, almost triple that of January 2012 (8,020 birds). The graph shows the official census figures for January in the last 23 years. The interpretation must be made with caution, because of the large difference in census coverage over the years (very low in 2011 or 2009, for example, and several years without information). Still, there is a very clear upward trend, as already stated in a previous post. However, the distribution of the species is restricted to a few locations, the same as contained in the censuses of the early 1990s, over two decades ago.
The most prominent location is again Vegas Altas (#1), which has primarily rice stubble and, to a lesser extent, corn and other crops. Within the wide area available each year, most are concentrated in the eastern part of the county, it being too complicated to count scattered foraging areas and roosts (although in some seasons, as in 2007, there were more than 8,000 geese in Sierra Brava reservoir). On 14 and 15 January 2013, there were estimated 18,800 greylag geese, mostly at Logrosán municipality (15,000), and the rest between Madrigalejo (3000), Navalvillar de Pela (600) and other localities (200). This is the highest known, thanks to the good condition of the flooded rice fields. Quite the opposite during the dry winter before, when in January 2012, just over 4,000 geese were counted. The previous high dating back to January 2006, when there were 13,800 Greylag Geese.
The remaining traditional greylag locations for winter populations harbored more modest numbers and in no case exceeded previous highs. So, in the reservoir of El Borbollón (#3) 186 were counted compared to the 458 of 2005. In Gabriel y Galán reservoir (#4) there were only 156 birds, half the maximum of 300 in 2000. Portaje reservoir (#5) had 206 geese in 2013, and the maximum was 293 in 2006. In Salor reservoir (#6), and nearby wetlands, there were only 56 individuals. The geese wintering in Llanos de Cáceres may vary location according to the years, the last two being focused on Valdesalor, when before they were at the ebmalse de Guadiloba, with the most in the region (250 birds in 2006). Los Canchales reservoir (#7) was the third location in importance in 2013, with 377 individuals, still far from the 900 of January 2000. Meanwhile, the Torremejía lagoons (#8) had 206 birds, well below the 1,050 peak of January 1999. This subpopulation occupies both these lagoons as Alange reservoir depending on water levels. Finally, the Llerena-Arroyoconejos reservoir (#7) showed a figure of 120 geese, far below the 1,100 in 2002. Although in other locations there can be geese in winter, they are not regular wintering areas. So in the January 2013 census, there were19 sites, and in January 2012, 21 sites. Other censuses, show more than 80 places with a greylag presence, in some cases it could be semi-domestic geese.
Collaborators. Emilio Peña, Adrián Chaves, Alberto Pacheco, Amado Franco, Andrés Maestre, Ángel Luis Sánchez, Ángel Sánchez, Antonio Calvo, Benigno Cienfuegos, Carlos Fernández, Casimiro Corbacho, César Clemente, Daniel Vicente, Dave Langlois, Diego Recio, Domingo Jiménez, Domingo Rivera, Emiliano Godoy, Emilio Costillo, Eva Palacios, Federico Hernández, Felipe Paniagua, Fernando Yuste, Francisco Bernáldez, Francisco Montaño, Godfried Schreur, Heliodoro Barquero, Inés García, Iván Castro, Iván Sánchez, Jasper Quak, Javier Briz, Javier Caballero, Javier Fernández, Javier Mahíllo, Javier Prieta, Jesús Montero, Jesús Porras, Jesús Solana, Joaquín Fernández, Joaquín Vázquez, John Muddeman, José Antonio Román, José Carlos López, José Fernández, José Luis Bautista, José Luis Caballero, José Manuel Rama, José María Guerrero, José Guerra, Juan Carlos Paniagua, Juan Fernández-Blanco, Juan Fernando Trejo, Juan José Blanco, Juan Pablo Prieto, Juan Rodríguez, Julián Panadero, Lorenzo Alcántara, Luis Lozano, Luis Salguero, Manuel Flores, Manuel García del Rey, Manuel Gómez Calzado, Manuel Rodríguez, Marc Gálvez, Marcelino Cardalliaguet, María José Moreno, Martin Kelsey, Miguel Ángel Romo, Óscar Llama, Paula Rodríguez, Rafael Alberto Rubio, Samuel Langlois, Santiago Cáceres, Sergio Mayordomo, Sergio Pérez y Vicente Risco. Coordinador: Javier Prieta.