Patagonia Austral Research Articles

Using Landsat Image Series to Identify and Characterize Persistent Oceanographic Structures in a Dynamic Marine Protected Area (North of San Jorge Gulf, Argentinian Patagonia)

Coastal oceanographic processes, like up- and downwelling, topographic fronts, etc., have consequences in biological communities. In some cases, these processes show up as surface structures observable in satellite imagery at different scales. In this work, we focus on the persistent structures observed in the coastal marine protected area of Parque Interjurisdiccional Marino-Costero Patagonia Austral (PIMCPA), one of the most relevant areas of the Argentine coast in terms of biodiversity and productivity. Using 80 Landsat-8 30 m-resolution images from the years 2017–2021, more than 20 structures were identified in the PIMCPA that appear consistently across seasons in approximately the same areas. We focus on four of them, those that are persistent and of medium scale, whose dimensions do not extend in most cases more than 10 km from their region of generation, and describe their location and shape in detail, and analyze their dependence on forcing variables such as tides, wind, bathymetry, and seasonality. Tidal currents prove to be the most significant variable in the formation and evolution of the structures described, above wind or seasonal stratification, which play only a secondary role.

A sea bottom classification of the Robredo area in the Northern San Jorge Gulf (Argentina)

Benthic habitats are primarily determined by the nature of the substrate (i.e., the type of sediment or rock) and by the bathymetry (e.g., light availability, current, or waves exposition) both determining the viability of infaunal organisms. In this sense multibeam (MB) echosounders provide more data about the sea bottom than any other acoustic technique. During the 2014 Argentine-Canadian survey of the RV Coriolis II in the Gulf of San Jorge, MB data were acquired in the area of Robredo, west of the Marine Protected Area (MPA) Parque Interjurisdiccional Marino Costero Patagonia Austral (PIMCPA, Patagonia, Argentine). Acoustic data were affected by acquisition artifacts, so an ad hoc algorithm was required to restore the data. Moreover, during the survey, dredge samples were also acquired where acoustic data suggested changes in substrate properties, and two later scientific surveys acquired video transects of the sea bottom that allowed also a basic classification. A non-supervised classification of the seabed was performed, using a subsampling and voting algorithm, with the acoustic and bathymetric data. The final classification is in agreement with groundtruthing (dredge samples and video transects), showing that bottom structure complexity leads to a meaningful picture of the sea bottom classes in the area. Our results reveal that Robredo has two subareas, one with a fine substrate (west) and another with a coarse substrate (east), the latter being also characterized by outcropping rock formations of marked relief. Despite the small spatial coverage of the survey, the resulting sea bottom classification presented in this paper has described, for the first time, some important features of the benthic geohabitats in the PIMCPA.

Spatial use of multiple jurisdictions by Magellanic penguins and assessment of potential conflicts in the face of changing trawl fisheries scenarios

Seabirds often have wide distribution ranges and may travel relatively long distances to breeding grounds, often crossing jurisdictional boundaries. When engaged in foraging behaviour, seabirds are prone to interact with different fisheries and suffer incidental mortality. We assessed the spatial use of foraging Magellanic penguinsSpheniscus magellanicusbreeding at 3 colonies within the Patagonia Austral Marine Park (San Jorge Gulf, Argentina) in relation to different jurisdictions. We also quantified their spatial overlap with 3 trawl fisheries and bycatch (incidental mortality), an interaction previously reported in the region. Breeding Magellanic penguins mainly used waters under provincial jurisdiction within the gulf, with some use of federal waters depending on the breeding season and colony location. Spatial use by breeding penguins resulted in a variable but relatively low overlap with the operations of the 3 fishing fleets in 2014-2016 (1.1-26.3%). Changes in the spatial distribution of fishing operations in recent years resulted in a lower overlap than in 2005-2007 (12.1-60.8%). Incidental mortality during 2008-2014 was also variable and relatively low (0.0-0.363 birds per haul). Breeding Magellanic penguins foraged outside protected area boundaries where they can spatially overlap with and face potential threats from different fishing fleets that operate in waters of provincial and/or federal jurisdiction. Despite the current low spatial overlap, the relatively fast changes in fishing patterns in the recent past draw attention to the need for continuous monitoring. Data obtained in this study may prove valuable in case the implementation of spatial and temporal closures of fishing operations is needed.

New information of stopover sites for Chloephaga geese in central Patagonia: potential implications for Ruddy-headed Goose (Chloephaga rubidiceps) conservation

Three migratory species of sheldgeese (Chloephaga spp.) make seasonal movements across a large portion of the Argentine territory. All three of these species have been affected by anthropogenic actions which have caused dramatic population drops, especially for the Ruddy-headed Goose (Chloephaga rubidiceps). Although telemetry techniques have rapidly advanced, knowledge of the migratory routes of many Neotropical birds is still incipient. The study of migration routes should be a top priority, especially when conservation and management actions are necessary along the main migratory routes. The goal of this work is to present new evidence of important stopover sites and concentration areas of migratory sheldgeese in eastern Patagonia. We conducted fieldwork during the fall, winter and spring of 2017, all of 2018 and the summer of 2019 in Chubut province, Argentina. We identified one stopover area for sheldgeese within a recently created protected area, the Parque Interjurisdiccional Marino Costero Patagonia Austral (PIMCPA), that could be a key site for the protection of the three species, in particular for the Ruddy-headed Goose. Results will provide input for decision-making processes during the design of future infrastructure projects already planned in eastern Patagonia along the migratory route of several species.

Base de Información Bioantropológica de Patagonia Austral (B.I.B.P.A)

Los restos óseos humanos de Patagonia Austral se encuentran dispersos en numerosas instituciones europeas y americanas. Actualmente se contabilizan más de 1150 individuos. Esos sujetos y la información de orden bioantropológica publicada acerca de cada uno de ellos ha sido compilada en la Base de Información Bioantropológica de Patagonia Austral. Esta plataforma se concibe como una herramienta que busca facilitar y agilizar la labor de la comunidad de antropólogos biólogos y afines, de la región. Es de carácter público y código abierto, y se encuentra a disposición tanto de la comunidad científica como de la sociedad. Se actualizará de manera periódica, con la información que la comunidad genere y ponga a disposición de sus pares a través de los diversos formatos que los científicos tienen para difundir su labor científica.

Raúl González Tuñón en el país del viento. Crónicas escritas y periodismo en el viaje a la Patagonia

El artículo analiza las crónicas periodísticas (nunca editadas en libro) que el poeta argentino Raúl González Tuñón publicó en el diario Crítica en 1932 como corresponsal viajero a la Patagonia Austral. Más allá de los objetivos explícitos y utilitarios del viaje del escritor propuestos por el diario (impedir que la Patagonia quede aislada por la supresión de una línea aérea nacional), se examina la complejidad de estas corresponsalías para estudiar las diversas formas enunciativas en las notas de González Tuñón, la reescritura y apelación a saberes literarios y culturales sobre ese espacio geográfico, las elecciones ideológicas y estéticas en la construcción del itinerario del viaje y en las formas de la representación, y la intervención de denuncia y de contenido político y social que configura a la Patagonia como un espacio problemático, escenario permanente de crisis laborales y gremiales y terreno propicio para el conflicto obrero.

Analysis of a southern sub-polar short-term ozone variation event using a millimetre-wave radiometer

Abstract. Subpolar regions in the Southern Hemisphere are influenced by the Antarctic polar vortex during austral spring, which induces high and short-term ozone variability at different altitudes, mainly into the stratosphere. This variation may affect considerably the total ozone column changing the harmful UV radiation that reaches the surface. With the aim of studying ozone with a high time resolution at different altitudes in subpolar regions, a millimetre-wave radiometer (MWR) was installed at the Observatorio Atmosférico de la Patagonia Austral (OAPA), Río Gallegos, Argentina (51.6∘ S, 69.3∘ W), in 2011. This instrument provides ozone profiles with a time resolution of ∼1 h, which enables studies of short-term ozone mixing ratio variability from 25 to ∼70 km in altitude. This work presents the MWR ozone observations between October 2014 and 2015, focusing on an atypical event of the polar vortex and Antarctic ozone hole influence over Río Gallegos detected from the MWR measurements at 27 and 37 km during November of 2014. During the event, the MWR observations at both altitudes show a decrease in ozone followed by a local peak of ozone amount of the order of hours. This local recovery is observed thanks to the high time resolution of the MWR mentioned. The advected potential vorticity (APV) calculated from the MIMOSA high-resolution advection model (Modélisation Isentrope du transport Méso-échelle de l'Ozone Stratosphérique par Advection) was also analysed at two isentropic levels (levels of constant potential temperature) of 675 and 950 K (∼27 and ∼37 km of altitude, respectively) to understand and explain the dynamics at both altitudes and correlate the ozone rapid recovery with the passage of a tongue with low PV values over Río Gallegos. In addition, the MWR dataset was compared for the first time with measurements obtained from the Microwave Limb Sounder (MLS) at individual altitude levels (27, 37 and 65 km) and with the differential absorption lidar (DIAL) installed in the OAPA to analyse the correspondence between the MWR and independent instruments. The MWR–MLS comparison presents a reasonable correlation with mean bias errors of +5 %, −11 % and −7 % at 27, 37 and 65 km, respectively. The MWR–DIAL comparison at 27 km also presents good agreement, with a mean bias error of −1 %.

Osteocondritis disecante. Primeros resultados en restos humanos de cazadores-recolectores del Holoceno en Patagonia austral

La osteocondritis disecante (OCD) es una patología que afecta el cartílago articular y el hueso subcondral en las epífisis articulares de humanos y otros mamíferos. A pesar de que su etiología es multifactorial, la presencia de esta lesión ha sido frecuentemente atribuida a microtraumatismos reiterados por los efectos de la actividad física sobre las articulaciones afectadas. Este trabajo involucra un primer paso en el estudio de esta patología en restos humanos de Patagonia Austral, la cual no fue analizada en forma sistemática. El objetivo es analizar la variabilidad de la OCD en un conjunto de restos humanos de 26 individuos adultos pertenecientes a sociedades de cazadores-recolectores de esta región durante el Holoceno medio-tardío (ca. 5200-70 años AP) y su posible relación con la edad, el sexo, la dieta, la cronología y el geográfica de procedencia. Se discute si su expresión está vinculada con los patrones de actividad física desarrollados por los grupos, en función de las prácticas económicas llevadas a cabo. La prevalencia general observada en esta muestra (42,3%), mayor a la reportada para poblaciones actuales, sugiere que la actividad física habría desempeñado un rol importante en el desarrollo de la OCD en al menos parte de las personas afectadas.

Información bioantropológica publicada de Patagonia Austral. Un abordaje de la situación actual desde el data-sharing

Los avances técnicos de las últimas décadas han incidido en el ámbito científico conllevando un aumento en la generación de nuevos conocimientos. Estos nuevos desarrollos han permitido mejorar las comunicaciones y el acceso a la información. En estas condiciones, aparece una corriente global, el data sharing, que aboga por la libre puesta en disposición de los datos producto de las investigaciones científicas. Esta tendencia no está desarrollada en el área de Patagonia Austral. Sin embargo, antes de intercambiar datos, es importante conocer qué tipo de información se puede o pretende compartir. Con el fin de acercarnos a la situación en la que se encuentra la información disponible en la región, se realizó un análisis bibliográfico de las principales revistas donde se publican artículos del ámbito de la bioantropología en Patagonia Austral. Se analizaron 18 variables en 88 artículos. Los resultados mostraron que, si bien el dato final de la investigación es presentado de manera correcta, no lo es la información que contextualiza ese dato, los metadatos. Se plantea la necesidad de que la comunidad bioantropológica siente unas bases que permitan estandarizar aquello que se quiera compartir en un futuro, con especial atención a los metadatos.

Comparison of ozone profiles from DIAL, MLS, and chemical transport model simulations over Río Gallegos, Argentina, during the spring Antarctic vortex breakup, 2009

Abstract. This study evaluates the agreement between ozone profiles derived from the ground-based differential absorption lidar (DIAL), satellite-borne Aura Microwave Limb Sounder (MLS), and 3-D chemical transport model (CTM) simulations such as the Model for Interdisciplinary Research on Climate (MIROC-CTM) over the Atmospheric Observatory of Southern Patagonia (Observatorio Atmosférico de la Patagonia Austral, OAPA; 51.6° S, 69.3° W) in Río Gallegos, Argentina, from September to November 2009. In this austral spring, measurements were performed in the vicinity of the polar vortex and inside it on some occasions; they revealed the variability in the potential vorticity (PV) of measured air masses. Comparisons between DIAL and MLS were performed between 6 and 100 hPa with 500 km and 24 h coincidence criteria. The results show a good agreement between DIAL and MLS with mean differences of ±0.1 ppmv (MLS − DIAL, n = 180) between 6 and 56 hPa. MIROC-CTM also agrees with DIAL, with mean differences of ±0.3 ppmv (MIROC-CTM − DIAL, n = 23) between 10 and 56 hPa. Both comparisons provide mean differences of 0.5 ppmv (MLS) to 0.8–0.9 ppmv (MIROC-CTM) at the 83–100 hPa levels. DIAL tends to underestimate ozone values at this lower altitude region. Between 6 and 8 hPa, the MIROC-CTM ozone value is 0.4–0.6 ppmv (5–8 %) smaller than those from DIAL. Applying the scaled PV (sPV) criterion for matching pairs in the DIAL–MLS comparison, the variability in the difference decreases 21–47 % between 10 and 56 hPa. However, the mean differences are small for all pressure levels, except 6 hPa. Because ground measurement sites in the Southern Hemisphere (SH) are very sparse at mid- to high latitudes, i.e., 35–60° S, the OAPA site is important for evaluating the bias and long-term stability of satellite instruments. The good performance of this DIAL system will be useful for such purposes in the future.

Epigean Tenebrionids (Coleoptera: Tenebrionidae) from Leones and Tova-Tovita Islands (Chubut, Argentina) and Its Comparison with the Mainland Assemblage

The Parque Interjurisdiccional Marino Costero Patagonia Austral (PIMCPA) protects over 180 km of Patagonian Atlantic coastline of northern San Jorge gulf, including an archipelago that comprises more than 39 islands. In this work, we studied the darkling beetles (Coleoptera: Tenebrionidae) of the two largest islands in the PIMCPA archipelago: Leones and Tova-Tovita. Tenebrionids are reported for first time in these islands, in addition, we described their species assemblage. Likewise, a comparison between the islands and the mainland was also performed. The GLM, MDS, ANOSIM and PCA methods were employed. Islands share the same tenebrionid species assemblage but they differ from that displayed on the mainland. Considering both islands as a whole, the insular assemblage shows lower species richness and diversity than those seen in the mainland. We identified eight species in the islands which belong to eight genera and four tribes. We also found that six of these species were shared among islands. Psectrascelis punctipennis Kulzer was exclusively recorded from the Tova-Tovita, while Platesthes kuscheli Kulzer from the Leones island. The island assemblage is mainly composed of nocturnal or crepuscular species [including Praocis (Hemipraocis) sellata bergi Burmeister, Patagonogenius quadricollis (Fairmaire), Emmallodera crenaticostata crenaticostata Blanchard and Scotobius akidioides akidioides Waterhouse], while several diurnal species of Nyctelia Berthold are the most common and diverse darkling beetles among mainland fauna. Additionally, we discuss the effects of the mainland distance, paleoclimate, and the origin of insular assemblages. Finally, other insular implications of tenebrionid beetles are discussed.

Reestructuración productiva en Patagonia Austral. Alternativas de desarrollo en Santa Cruz y sus mercados de trabajo

Las Provincias de Chubut, Santa Cruz y Tierra del Fuego, conforman el subsistema regional de la Patagonia Austral. Al caracterizar cada una de dichas provincias, se han visualizado sectores económicos que componen sus respectivas estructuras de producción, pudiéndose observar la evolución que han presentado en su desarrollo.Su análisis, permitió conocer la adaptación de la región a los cambios operados en la economía y particularmente en los mercados de trabajo a partir de la reestructuración de los años ´90.Especial atención merecieron aquellos sectores considerados como enclaves, predominantes en las estructuras económicas de la región, y cuyos comportamientos reflejaron importantes modificaciones a partir de políticas neo liberales llevadas a cabo a través de la Reforma del Estado de fines de la década de los ´80. La apertura económica, el predominio de las privatizaciones –de gran impacto en Patagonia Austral-, la desindustrialización, el aumento del desempleo, la flexibilización laboral, la desregulación financiera, generaron importantes transformaciones, modificando la estructura social del trabajo y las condiciones de vida de la población a nivel nacional.La crisis post devaluatoria de 2001 y la recuperación de un Estado presente dieron lugar a nuevas condiciones económicas imperantes y con ello la construcción de un nuevo escenario regional. Sectores económicos emergentes, al amparo de condiciones favorables hicieron posible pensar en una reconfiguración de la tradicional matriz productiva provincial -basada en producciones tradicionales y la renta estatal-.Por su parte, la crisis financiera internacional de 2008 modificó sustancialmente el entorno, profundizando la pérdida de competitividad lograda con la devaluación, iniciando un nuevo ciclo inflacionario interno, e impactando fuertemente en nuestra economía y en el nuevo perfil productivo emergente.Más allá de ello, el modelo que ha prevalecido en la Provincia de Santa Cruz ha sido caracterizado por este mismo equipo investigador como de carácter subsidiador y rentista, advirtiendo que la mayor parte de la población “no vive” de las producciones propias de la región (carbón, petróleo, gas, minería e industria), sino que se beneficia con la redistribución que realiza el Estado por la explotación exógena de dichos recursos y la percepción de regalías, garantizando con ello mejores condiciones de vida a sus habitantes.

Distribution and origin of trace metals in sediments of a marine park (Northern San Jorge Gulf) from Argentina

The Northern San Jorge Gulf (NSJG) was designated Interjurisdictional Coastal Marine Park “Patagonia Austral” in 2008 with the objective of conserving biodiversity and natural resources. Metals released to the environment can be accumulated by organisms and can be toxic in some cases, making it necessary to evaluate their presence and biological risk. This study examined concentrations of Fe, Mn, Zn, Cu, Cr, Ni, Cd and Pb in intertidal sediments of the NSJG, and was the first study of its kind to be conducted in this area. Concentrations of all metals fell below biological risk levels. Anthropogenic enrichment was only found for Ni around the Aristizábal lighthouse and was attributed to the frequent oil spills that impact this particular area.

The Third Danish Scientific Expedition to Patagonia and Tierra del Fuego, 1982–83

Frederiksen, Peter: The Third Danish Scientific Expedition to Patagonia and Tierra del Fuego, 1982,83. Geografisk Tidsskrift 84: 1–5. Copenhagen January 1984. Soil and landscape mapping of Tierra del Fuego and Patagonia austral was executed based on LANDSAT false colour composite images, and ground control (augerings and profile studies). A dear relation between 1) the images patterns and land units was established. Further a basis for comparison between northern and southern hemispheric soil development in regions influenced by Pleistocene glaciations was established.