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Upland Goose Chloephaga picta, Ashy-headed Goose Chloephaga poliocephala and Ruddy-headed Goose Chloephaga rubidiceps are endemic goose-like threatened birds of southern South America. This work aimed to study how sheldgeese are distributed both temporally and spatially and characterize their habitat use in part of their breeding range in Southern Argentina, a little-explored subpolar region. We conducted nine surveys between spring 2013 and summer 2016 across a maximum of 235 km in Santa Cruz and 698 km in Tierra del Fuego per survey. We recorded the presence of non-breeding sheldgoose groups and Upland Goose pairs. We collected data at site-scale (~ 0.8 km2) and extracted data from geographic information systems for landscape-scale (5 km2) analyses. We recorded 2396 non-breeding groups containing one, two or the three species, 788 Upland Goose pairs and 102 solitary individuals. The Upland Goose was present in almost all groups and was the most abundant sheldgoose, followed by the Ashy-headed Goose. The Ruddy-headed Goose was observed only in 15 locations. Poa grasslands, meadows and Festuca grasslands were the habitats in which we detected most individuals. Sheldgoose density was higher in Tierra del Fuego than in Santa Cruz, and increased from spring to autumn and decreased in winter. The largest sheldgoose groups were concentrated in meadows and waterbodies. Sheldgeese selected sites with greater habitat diversity, habitat richness and number of habitats patches. Our results provide information to understand which environmental conditions favour sheldgeese and to aid in the selection of important areas for the conservation of these species.

Conflicts between waterfowl and agriculture are common in many nations around the world. However, these birds can also provide a variety of benefits that humanity can obtain from nature. There are three migratory and endemic sheldgeese (Ruddy-headed Goose Chloephaga rubidiceps, Ashy-headed Goose Chloephaga poliocephala and Upland Goose Chloephaga picta) which are species of conservation concern in Argentina. Sheldgeese are in constant conflict with the agricultural practices in the Pampas region of Argentina. The objective was to measure possible damages and benefits due to geese grazing on winter wheat crops during different growth stages, in the southeast of Buenos Aires province, Argentina. We established a stratified random plot design in nine fields, where we placed geese exclosure plots and plots without exclosure, allowing sheldgeese to graze. From May to September, we visited each field every two weeks. We performed transects where we counted and collected feces in order to estimate the grazing intensity. We analyzed the total concentration of Nitrogen (N) and Phosphorus (P) in the feces in the period before and after the wheat emergence. We also performed microhistogical analysis to evaluate sheldgeese diet in these two periods. During the crop growth and at harvest, we evaluated possible damages (wheat cover, percentage of eaten plants, percentage of eaten tillers, chlorophyll content, grain yield per plot, harvest index, weight of 1000 grains) and benefits (number of tillers per plant, percentage of weed cover, protein content) of geese grazing. We found that sheldgeese grazing varied along the different visits and among the experimental fields. Geese grazing negatively affected the wheat cover but there was no effect on the final yield. The input of nutrients provided by sheldgeese feces was higher in the period after the crop emergence, when they only ate wheat. Results on the birds’ diet showed that they fed on weeds before wheat emergence thus providing an ecosystem service. In this study, we found elements that could help to shed light on the real impact of sheldgeese in crops and discovered some benefits that these birds could be providing to crops in the Pampas ecoregion.

Durante las últimas décadas, las poblaciones de cauquenes (Chloephaga sp.) en Argentina han disminuido drásticamente. En Bahía Franklin, Isla de los Estados, se registraron y estudiaron 21 nidos de Cauquén Común (Chloephaga picta) y 4 de Cauquén Real (Chloephaga poliocephala). Todos los nidos estaban ubicados en el suelo en sectores de pendiente muy baja. La distancia entre nidos fue de 216.6 y 973 m, su densidad de 0.10 y 0.02 nidos/ha y el tamaño promedio de puesta de 5.4 y 4.7 huevos para el Cauquén Común y el Cauquén Real, respectivamente. Los nidos estaban ubicados principalmente en el turbal graminoideo, seguido por el pastizal y el arbustal. Las plantas predominantes en las inmediaciones del nido fueron Marsippospermum grandiflorum, Poa flabellata, Empetrum rubrum y Chiliotrichum diffusum, con una altura promedio de la vegetación de 72 cm en los nidos del Cauquén Común y 97 cm en los del Cauquén Real, y una baja cobertura. Se observó una asociación espacial interespecífica, posiblemente de tipo “nidificación protectora”, entre ambos cauquenes con el Pingüino Penacho Amarillo (Eudyptes chrysocome) y el Pingüino Patagónico (Spheniscus magellanicus). En el sur de la Patagonia, los perros (Canis lupus familiaris) y el visón americano (Neovison vison), entre otras especies nativas y exóticas, están provocando consecuencias negativas para la nidificación de los cauquenes. La Isla de los Estados aún no ha sido colonizada por estos predadores, lo que la hace un sitio de importancia para la reproducción y conservación de estas aves amenazadas. During the last decades wild geese (Chloephaga sp.) populations in Argentina have decreased dramatically. We recorded and studied 21 nests from the Upland Goose (Chloephaga picta) and 4 from the Ashy-headed Goose (Chloephaga poliocephala) in Bahía Franklin, Staten Island. All the nests were located on the ground in low slope areas. Distances between nests were 216.6 and 973 m, nest densities were 0.10 and 0.02 nests/ha, and clutch size was 5.4 and 4.7 eggs for the Upland Goose and the Ashyheaded Goose, respectively. Nests were located mainly on the graminoid bog, followed by grasslands and shrubby areas. Predominant plants near the nest were Marsippospermum grandiflorum, Poa flabellata, Empetrum rubrum and Chiliotrichum diffusum, with an average vegetation height of 72 cm for nests of the Upland Goose and 97 cm for nests of the Ashy-headed Goose, and low cover. We observed an interspecific spatial association between both species and the Rockhopper Penguin (Eudyptes chrysocome) and the Magellanic Penguin (Spheniscus magellanicus), possibly from the type “protective nesting”. In southern Patagonia dogs (Canis lupus familiaris) and the American mink (Neovison vison), among other native and exotic predators, have negative consequences for the nesting geese. Staten Island has not been yet colonized by these predators, thus highlighting the relevance of this site for the reproduction and conservation of these endangered species.

Summary. In Argentina, predominantly in the Pampas ecoregion, the natural rangelands have increasingly been replaced by crops. Avifaunal studies have shown that the population density of several species decreased as the proportion of cropland in the landscape increased. The Greater Rhea Rhea americana and two migratory sheldgeese: The Upland Goose Chloephaga picta and Ashy-headed Goose Chloephaga poliocephala, are medium-large native species that have been common and sympatric inhabitants of the Pampas ecoregion. We aimed to analyse and compare the current ecological niches occupied by the three species during the non-breeding season in the southern Pampas of Argentina, the region where their original distributions overlapped, using Ecological Niche Factor Analysis. The three species showed high global marginality values, indicating that they occupied only a specific subset of environmental conditions of those available across the region. Suitable areas for Greater Rhea were located in the west and south of the study area, overlapping grazing lands and native habitats. The three species responded to landscape composition and configuration, as indicated by the low proportion of areas with suitable conditions for these medium-large birds. Suitable areas for Ashyheaded and Upland Geese were especially concentrated in the eastern part of the area and suitable areas for Upland Goose were more widespread than those suitable for the Ashy-headed Goose. We provide compelling evidence of low overlap between the ecological niches of the three species in the southern Pampas, which highlights the need for specific management strategies to ensure the conservation of these emblematic species.-Pedrana, J., Bernad, L., Maceira, N.O. & Isacch, J.P. (2018). Niche overlap determination through habitat suitability models: A management tool for native birds of the Argentinean Pampas. Ardeola, 65: 25-40. Fil: Pedrana, Julieta. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina Fil: Bernad, Lucia. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina Fil: Maceira, Nestor Oscar. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina Fil: Isacch, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina

Sheldgeese species are currently the subject of serious conservation concern and have been a source of historical conflict with agricultural interests. Here we assess the relative effects of environmental and anthropogenic predictors on Sheldgeese (Ruddy-headed Goose Chloephaga rubidiceps, Ashy-headed Goose Chloephaga poliocephala and Upland Goose Chloephaga picta) distribution in the southern Pampas at different spatial scales. These birds were declared an “agriculture plage” by the government and this conflict with humans has been so far resolved with species persecution. We evaluate whether its current wintering distribution is shaped by anthropogenic disturbances or whether it can be better explained by differences in topography and preference for wetlands, or by landscape composition and configuration. We characterized the study region using 17 potential predictors related to environmental, human and landscape characteristics. We built habitat-suitability models to examine the relative effect of the variables on the regional occurrence of Sheldgeese. We performed vehicle surveys in southern Buenos Aires province, in two years (2011–2012), surveying 9200 km of roads and recording 281 Sheldgeese flocks. Generalized additive models were used to model the presence/absence of Geese in 250-m cells. The habitat suitability models of Sheldgeese suggest that: (1) areas of low elevation surrounded by waterbodies are one of the main positive drivers of species distribution, (2) centers of human activity, which are regions with greater road accessibility, have a negative impact on species distribution, (3) heterogeneous landscape composed of croplands and grazing fields are preferred environments Fil: Pedrana, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina Fil: Bernad, Lucia. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina Fil: Maceira, Nestor Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina Fil: Isacch, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina

Summary Aspergillosis in Wild Goose (Chloephaga poliocephala Scl., 1857) in Chile The first report of Aspergillus fumigatus in wild goose (Cloephaga poliocephala Scl., 1857) in the South of Chile is presented. The diagnosis was carried out considering the anatomo-pathological characteristics of the lesions and the isolation identification of the aethiological agent according to Thom and Raper's methodology. Resumen Se comunica el primer hallazgo de Aspergillus fumigatus en ganso silvestre (Chloephaga poliocephala) en el sur de Chile. El diagnostico fue realizado considerando caracteristicas anatomopatologicas de las lesiones presentes y aislamiento e identificacion del agente etiologico mediante la clave de Thom y Raper (1945). Zusammenfassung Aspergillose bei Wildgansen (Graukopfgans, Chloephaga poliocephala Scl., 1857) in Chile Es wird der erste Fall von Aspergillus-fumigatus-Mykose bei einer Wildgansart (Graukopfgans, Chloephaga poliocephala) im Suden Chiles mitgeteilt. Die Diagnose wurde aufgrund pathologischanatomischer Befunde und durch Isolierung und Identifizierung des atiologischen Agens mittels des Schlussels von Thom und Raper (1945) gestellt.