The impact of exotic plants on the stopover behavior of migrant bird species is poorly understood... more The impact of exotic plants on the stopover behavior of migrant bird species is poorly understood. As a general hypothesis, it can be supposed that habitat change due to the presence of exotic plants will affect migrants, having a negative impact on bird abundance, on avian community assemblage, and/or on fuel deposition rate. To test these predictions, we used data obtained in August 2011 at a ringing station in a coastal wetland in northern Iberia which contained both unaltered reedbeds (Phragmites spp.) and areas where the reedbeds had been largely replaced by the invasive saltbush (Baccharis halimifolia). Passerines associated with reedbeds during the migration period were used as model species, with a particular focus on sedge warblers (Acrocephalus schoenobaenus). The saltbush promoted a noticeable change on bird assemblage, which became enriched by species typical of woodland habitats. Sedge warblers departed with a higher fuel load, showed a higher fuel deposition rate, and ...
Since 1999 we are monitoring the hobby population that distributes in Bizkaia. Until now we have ... more Since 1999 we are monitoring the hobby population that distributes in Bizkaia. Until now we have sea¡ched 41 territories. These territories a¡e on Atlantic landscape (5), on sublitoral landscape (14), on interior landscape (13) and on mountain areas (9). Most ofterritories we¡e in forestry lands, all areas where hobbies nested were mature and with a medium covert area. We found lloccupied nests, they were made by Carrion Crows, and the mean distance from the ground was 27,16m. The average date oflaid was 28ü ofJune and the average ofchicks that flight was 2,4.
The breeding season of birds of prey and owls is usually so long that they rarely produce more th... more The breeding season of birds of prey and owls is usually so long that they rarely produce more than one clutch per year (i.e. Newton, 1979; Cramp & Simons, 1985; Donazar, 1993; Zuberogoitia et al., 2002). In fact, the onset of one breeding season occurs relatively soon after the end of the previous season (Newton, 1979; Marti, 1994; Taylor, 1994; Zuberogoitia, 2000; Zuberogoitia et al., 2002). Second broods have been rarely reported for owls (Kellomäki et al., 1977; Mikkola, 1983; Cramp & Simmons, 1985; Millsap & Bear, 1990; Martínez et al., 2003). Only Barn Owls Tyto alba produce re-gularly two or three clutches yearly (Marti, 1994; Taylor, 1994; Martínez & López, 1999; Zuberogoitia, 2000). Nevertheless, replacement clutches (if first clutches fail early during incu-bation) are more common (Mikkola, 1983; Cramp & Simmons, 1985; Fry et al., 1988; Bull & Henjum, 1990; Forsman et al., 1997; Olsson, 1997). Producing second clutches is possible, for instance, if first clutches are laid ...
ABSTRACT Restoration and the creation of artificial wetlands can mitigate the loss and degradatio... more ABSTRACT Restoration and the creation of artificial wetlands can mitigate the loss and degradation of natural wetlands. The chief wetland areas in northern Iberia are the estuaries situated along the coast of the Bay of Biscay. These areas are tidal in nature and often small in size. These characteristics, together with high levels of human, disturbance can cause significant limits on the conservation of waterbirds. At the end of 2009, an old polder within the Urdaibai marshes in Spain was modified to create an artificial lagoon (Orueta Lagoon). The goal of this study was to evaluate the use of this lagoon by waterbirds, and its contribution to waterbird assemblage and richness at Urdaibai. Orueta Lagoon contributed 26.8% of total abundance, including 11 species not present in other zones of Urdaibai. Thus, it provided a new and attractive habitat for several waterbird species, especially ducks, coots and allies, shorebirds and grebes. Therefore, Orueta Lagoon plays a fundamental role in the enrichment of the waterbird assemblage at Urdaibai and hence is of great value from a conservation standpoint.
The impact of exotic plants on the stopover behavior of migrant bird species is poorly understood... more The impact of exotic plants on the stopover behavior of migrant bird species is poorly understood. As a general hypothesis, it can be supposed that habitat change due to the presence of exotic plants will affect migrants, having a negative impact on bird abundance, on avian community assemblage, and/or on fuel deposition rate. To test these predictions, we used data obtained in August 2011 at a ringing station in a coastal wetland in northern Iberia which contained both unaltered reedbeds (Phragmites spp.) and areas where the reedbeds had been largely replaced by the invasive saltbush (Baccharis halimifolia). Passerines associated with reedbeds during the migration period were used as model species, with a particular focus on sedge warblers (Acrocephalus schoenobaenus). The saltbush promoted a noticeable change on bird assemblage, which became enriched by species typical of woodland habitats. Sedge warblers departed with a higher fuel load, showed a higher fuel deposition rate, and ...
Since 1999 we are monitoring the hobby population that distributes in Bizkaia. Until now we have ... more Since 1999 we are monitoring the hobby population that distributes in Bizkaia. Until now we have sea¡ched 41 territories. These territories a¡e on Atlantic landscape (5), on sublitoral landscape (14), on interior landscape (13) and on mountain areas (9). Most ofterritories we¡e in forestry lands, all areas where hobbies nested were mature and with a medium covert area. We found lloccupied nests, they were made by Carrion Crows, and the mean distance from the ground was 27,16m. The average date oflaid was 28ü ofJune and the average ofchicks that flight was 2,4.
The breeding season of birds of prey and owls is usually so long that they rarely produce more th... more The breeding season of birds of prey and owls is usually so long that they rarely produce more than one clutch per year (i.e. Newton, 1979; Cramp & Simons, 1985; Donazar, 1993; Zuberogoitia et al., 2002). In fact, the onset of one breeding season occurs relatively soon after the end of the previous season (Newton, 1979; Marti, 1994; Taylor, 1994; Zuberogoitia, 2000; Zuberogoitia et al., 2002). Second broods have been rarely reported for owls (Kellomäki et al., 1977; Mikkola, 1983; Cramp & Simmons, 1985; Millsap & Bear, 1990; Martínez et al., 2003). Only Barn Owls Tyto alba produce re-gularly two or three clutches yearly (Marti, 1994; Taylor, 1994; Martínez & López, 1999; Zuberogoitia, 2000). Nevertheless, replacement clutches (if first clutches fail early during incu-bation) are more common (Mikkola, 1983; Cramp & Simmons, 1985; Fry et al., 1988; Bull & Henjum, 1990; Forsman et al., 1997; Olsson, 1997). Producing second clutches is possible, for instance, if first clutches are laid ...
ABSTRACT Restoration and the creation of artificial wetlands can mitigate the loss and degradatio... more ABSTRACT Restoration and the creation of artificial wetlands can mitigate the loss and degradation of natural wetlands. The chief wetland areas in northern Iberia are the estuaries situated along the coast of the Bay of Biscay. These areas are tidal in nature and often small in size. These characteristics, together with high levels of human, disturbance can cause significant limits on the conservation of waterbirds. At the end of 2009, an old polder within the Urdaibai marshes in Spain was modified to create an artificial lagoon (Orueta Lagoon). The goal of this study was to evaluate the use of this lagoon by waterbirds, and its contribution to waterbird assemblage and richness at Urdaibai. Orueta Lagoon contributed 26.8% of total abundance, including 11 species not present in other zones of Urdaibai. Thus, it provided a new and attractive habitat for several waterbird species, especially ducks, coots and allies, shorebirds and grebes. Therefore, Orueta Lagoon plays a fundamental role in the enrichment of the waterbird assemblage at Urdaibai and hence is of great value from a conservation standpoint.
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