Abstract:

Isolated rocky outcrops can act as patch habitats that host great biodiversity through the diversity of microhabitats, presence of restricted taxa and the high turnover of species in the patch matrix. The isolated rocky outcrops of Paraje Tres Cerros (ARPTC), Corrientes, Argentina, are a unique landscape in the region and biologically little explored. We conducted a study to describe for the first time the bird community of the forest and grassland of the ARPTC, using 136 lists following the ten species Mackinnon method from the breeding and non-breeding seasons. We evaluated the diversity, trophic guilds and phenology of the species, and compared attributes of grassland and forest communities. The total species richness was 107, with the forest being 1.3 times more diverse than the grassland. Completeness of inventories ranged from 83-90 % in the grassland and 88 to 99 % in the forest. The habitat complementarity was 62 %, indicating the presence of several species exclusive of forest and grassland habitats. The trophic structure of communities showed a good representation of insectivorous birds in both habitats. Frugivorous birds were more frequent in the forest and granivorous birds were more frequent in the grasslands. Due to the arrival of migrant species, both habitats had significantly higher richness in the breeding season than in the non-breeding season. Our results showed similar general aspects and patterns for bird communities and with specific studies for bird communities of rocky outcrops. The present study highlights the importance of the isolated rocky outcrops of Paraje Tres Cerros for the protection of local and regional bird biodiversity and represents a benchmark for the management and the protection of these ecosystems.

Author affiliation: Fandiño, Blas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundacion Amado Bondpland; Argentina. Provincia de Santa Fe. Ministerio de Medio Ambiente; Argentina

Author affiliation: Fernández, Juan Manuel. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Thomann, Maria Luz. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura; Argentina

Author affiliation: Cajade, Rodrigo. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Hernando, Alejandra Beatriz. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura; Argentina

Abstract:

Las palomas y cotorras pueden resultar perjudiciales para cultivos anuales en algunas regiones de Sudamérica. En este estudio analizamospatrones de uso de hábitat de las palomas torcaza (Zenaida auriculata), manchada (Patagioenas maculosa) y picazuró (P. picazuro) y la cotorra(Myiopsitta monachus) durante la primera emergencia del cultivo de soja en Entre Ríos, Argentina. Se estimó el uso y la disponibilidad de hábitatsy se calculó la selección mediante intervalos de confianza de Bonferroni. Ninguna de las 4 especies seleccionó el cultivo de soja. La paloma torcazaseleccionó rastrojos de trigo y colza, las palomas picazuró y manchada seleccionaron hábitats con árboles nativos e introducidos; finalmente,la cotorra común seleccionó hábitats con árboles introducidos. Esto reforzaría la hipótesis de que estas especies solo seleccionaron lotes concotiledones de soja cuando existe escasez de granos en el ambiente. Asumiendo que esta hipótesis sea verdadera, una alternativa para disminuirda˜nos por aves en soja en emergencia sería disuadirlas de utilizar los lotes de soja, ofreciendo granos para atraerlas a otros sitios y evitar queda˜nen el cultivo. Esta disuasión podría lograrse haciendo coincidir el espacio y la temporalidad de la siembra de soja con la cosecha de cultivosinvernales, o bien ofreciendo granos como atrayentes para las aves.

Pigeons and parrots can damage annual crops in some regions of South America. We analyzed bird damage patterns for Eared Doves (Zenaida auriculata), Spotted-winged Pigeon (Patagioenas maculosa), Picazuro Pigeon (P. picazuro), and Monk Parakeet (Myiopsitta monachus), during the emergence first seedtime in soybean crops in Entre Ríos, Argentina. We estimated habitat use and availability. Habitat selection was estimated by means of Bonferroni confidence intervals. None of the 4 species selected soybean fields. Eared Doves selected wheat and canola stubbles. Picazuro Pigeon and Spotted-winged Pigeon showed strong selection for both native and introduced wooded habitats. Finally Monk Parakeet selected habitats with introduced trees. These results reinforce the idea that these species only selected fields with soybean cotyledons when there is a shortage of grain in the environment. An alternative to reduce bird damage in soybean crops first seedtime could be to offer grains in alternative places to attract them away from the soybean fields. Deterrence could be achieved by coordinating spatio-temporality soybean planting with harvest of winter grain crops, or by offering grains attractive to birds.

EEA Paraná

Author affiliation: Dardanelli, Sebastian. INTA. Estación Experimental Agropecuaria Paraná; Argentina

Author affiliation: Fandiño, Blas. Santa Fe. Ministerio de Medio Ambiente; Argentina

Author affiliation: Calamari, Noelia Cecilia. INTA. Estación Experimental Agropecuaria Paraná; Argentina

Author affiliation: Canavelli, Sonia Beatriz. INTA. Estación Experimental Agropecuaria Paraná; Argentina

Author affiliation: Zaccagnini, Maria Elena. INTA. Instituto de Recursos Biológicos; Argentina