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Long-term socio-ecological research requires comprehensive assessments of biodiversity that overcome historical taxonomic biases, such as the strong focus on the vascular flora. This is particularly relevant at high latitudes where the richness of non-vascular plant species exceeds that of vascular species. Additionally, with respect to geographical regions, there is also a marked bias towards ecological and conservation research in the northern hemisphere. In contrast, few studies have investigated patterns of non-vascular species richness in relation to conservation priorities at sub- Antarctic latitudes, particularly in the sub-Antarctic Magellanic ecoregion. In this work, we contribute to overcome such taxonomic, geographical and ecoregional biases by moving outside these limits, and therefore “changing the lenses” that are commonly used to assess and conserve biodiversity. We implemented these new “biocultural lenses” by including, for the first time, bryophytes in the floristic inventory of the southernmost island of the American continent: Gonzalo Island (56°31’16.8’’S; 68°42’53.5’’W) in the Diego Ramírez Archipelago, Chile. The first bryological exploration of the Diego Ramírez archipelago, SW of Cape Horn, revealed a bryophyte flora composed of 14 species, eight liverworts and six mosses. This number of non-vascular plant species almost doubles the eight vascular plants present on the island. Consequently, with our study, we aim to fill a critical gap in the knowledge of the flora of the Diego Ramírez archipelago, and establish an integral floristic characterization for the long-term socio-ecological research and conservation of the southernmost archipelago of South America. Based on the field material collected, the new nomenclatural combination Chiloscyphus secundifolius (Hook. f. & Taylor) J.J.Engel is proposed. The moss flora comprises Amblystegium serpens, a widespread moss, yet hitherto unknown for sub-Antarctic Chile. The bryoflora of Diego Ramírez has its greatest affinities with that of the sub-Antarctic Magellanic ecoregion and Maritime Antarctica. None of the liverworts present on Gonzalo Island occurs on continental Antarctica; in contrast, four of the six mosses are shared between these two areas.

Resumen: Este trabajo propone un nuevo concepto para cambiar la percepción de los hábitats de alta montaña en la región subantártica de Cabo de Hornos, desde un “desierto altoandino” hacia “jardineras” donde prevalecen las interacciones ecológicas positivas. Este cambio lo generamos a través de una práctica de la filosofía ambiental de campo, que incluyó la investigación en conjunto con la composición de metáforas y el diseño de actividades de campo ecológica y éticamente guiadas. El nuevo concepto procura afinar la observación y comprensión de los hábitos de vida de las plantas de alta montaña, donde la cooperación favorece la riqueza de especies que co-habitan en los hábitats altoandinos. Se demostró que el hábito de crecimiento en “cojín” es muy frecuente en estos ambientes, tanto en plantas vasculares como en musgos. Para promover la valoración ética y sintetizar descubrimientos ecológicos de estas formas de vida y las interacciones positivas que establecen con otras especies, se compuso la metáfora: “Jardineras altoandinas subantárticas”. Abstract: This work proposes a new concept for changing the perception about the high mountain habitats in the sub-Antarctic region of Cape Horn, from a “high-Andean desert” toward gardens where positive ecological interactions thrive. We generate this change through a practice of field environmental philosophy that involved the composition of metaphors and the design of field activities guided with an ecological and ethical orientation. This new concept aims to refine the observation and understanding about the life habits of mountain’s plants, where cooperation enhances the richness of species that con-inhabit in these high-Andean habitats. We demonstrated that cushion life-habit prevails in these environments, among both vascular and non-vascular plants. To foster an ethical valuation and a synthesis of the ecological discoveries about these life habits and the positive interactions they establish with other species, we composed the metaphor: “High-Andean sub-Antarctic gardens”.

El Parque Etnobotánico Omora, ubicado en la ecorregión subantártica y en la Reserva de Biosfera Cabo de Hornos (55° S) es el sitio más austral de la red LTSER-Chile. El Parque protege la cuenca hidrográfica del río Róbalo, que provee de agua a Puerto Williams, la capital de la Provincia Antártica Chilena. El año 2008, se inició un estudio a largo plazo sobre la diversidad, historias de vida y distribución de insectos acuáticos asociados al río Róbalo, y otros cursos de agua en la isla Navarino. Estos estudios son de gran interés para la red LTSER-Chile y la ciencia mundial por tres razones: 1) las características climáticas únicas de los ecosistemas dulceacuícolas de la ecorregión subantártica de Magallanes, que contrastan con aquellas del Hemisferio Norte; 2) las respuestas de los insectos dulceacuícolas y sus ciclos de vida son muy sensibles a la temperatura, y bajo condiciones de gradientes térmicos del gradiente altitudinal del río Róbalo se pueden hacer predicciones bajo distintos escenarios de Cambio Climático Global; y 3) los ciclos de vida de insectos dulceacuícolas han sido muy poco estudiados en el suroeste de Sudamérica, e incorporando el gradiente latitudinal con estudios similares de respuestas fenológicas de los insectos dulceacuícolas incorporando otros sitios de la Red LTSER-Chile permitiría evaluar señales tempranas de esta biota al cambio climático global. The Omora Ehtonobotanical Park (55° S) is the southernmost site of the LTSER network-Chile and the interdisciplinary research center of the Cape Horn Biosphere Reserve in the sub-Antarctic Magellanic ecoregion. The park protects the Róbalo River watershed that provides water to Puerto Williams, the capital of the Chilean Antarctic Province. In 2008, we initiated long-term studies on the diversity, distribution and life histories of aquatic insects associated with the Róbalo River and other streams on Navarino Island. These studies are of major interest to the LTSER-Chile network and to world science for three reasons: 1) the unique climatic characteristics of the sub-Antarctic Magellanic ecoregion, which contrast with those of the Northern Hemisphere; 2) responses of freshwater insects and their life cycles are very sensitive to temperature, and along the thermic variations associated with the altitudinal gradient of the Róbalo River we can make predictions for various scenarios of Global Climate Change; 3) the life cycles of freshwater insects have been understudied in southwestern South America, and by incorporating similar studies of phenological responses of freshwater insects at other sites LTSER-Chile sites along a latitudinal gradient will allow us to assess early signals of this biota to global climate change.

Invasive exotic species of mammalian predators represent a major cause of vertebrate animal extinctions on islands, particularly those that lack native mammalian carnivores. In 2001, the American mink (Mustela vison) was recorded for the first time on Navarino Island, in the Cape Horn Biosphere Reserve (55° S) in Chile, representing the southernmost population of mink worldwide. In order to assess its potential impact on native fauna, we studied its diet on Navarino Island, as part of an integrative management program on invasive species. Over a three-year period (2005-2007) we collected 512 scats in semi-aquatic habitats: marine coasts, riparian and lake shores. Overall, the main prey was mammals (37 % biomass), and birds (36 %), followed by fish (24 %). Over the spring and summer, mink consumed significantly more birds, whereas mammals constituted the main prey over the autumn and winter when migratory birds had left the area. Among birds, the mink preyed mainly on adult Passeriformes, followed by Anseriformes and Pelecaniformes, caught as chicks. Among mammals, the exotic muskrat (Ondatra zibethicus) was the most important prey, and together with the native rodent Abrothrix xanthorhinus it accounted for 78 % of the biomass intake. For an integrated management of invasive exotic mammal species on Navarino Island and in the Cape Horn Biosphere Reserve it is important to further research interactions established here among the various introduced mammals, and to initiate immediate control of the mink population in its initial stage of invasion. Las especies exóticas de mamíferos carnívoros invasores constituyen una de las principales causas de extinciones de vertebrados en islas, particularmente en aquellas que carecen de predadores mamíferos nativos. En 2001, el visón norteamericano (Mustela vison) fue registrado por primera vez en Isla Navarino en la Reserva de Biosfera Cabo de Hornos (55° S) en Chile, representando la población de visones más austral del mundo. Para estudiar su impacto potencial sobre la fauna nativa, estimamos su dieta en Isla Navarino como parte de un programa de control de especies invasoras. Durante tres años (2005-2007) colectamos 512 fecas en diversos habitats semiacuáticos: costa marina, riberas de ríos y lagos. La dieta consistió principalmente en mamíferos (37 % biomasa), aves (36 %) y peces (24 %). Durante la primavera y el verano el visón consumió significativamente más aves, sin embargo los mamíferos constituyeron la presa principal durante el otoño y el invierno, cuando las aves migratorias han abandonado la region. La depredación sobre aves afectó principalmente a Passeriformes adultos, seguidos por Anseriformes y Pelecaniformes que fueron capturados como polluelos. Respecto a los mamíferos, un roedor exótico, la rata almizclera (Ondatra zibethicus), fue la presa principal y junto al roedor nativo Abrothrix xanthorhinus constituyó el 78 % de la biomasa de presas de mamíferos. Para un manejo integral de especies de mamíferos exóticos invasores en Isla Navarino y la Reserva de Biosfera Cabo de Hornos es importante desarrollar investigación sobre las interacciones entre los mamíferos introducidos e iniciar un control inmediato de la población de visones en su estado inicial de invasión.

Invasive exotic species of mammalian predators represent a major cause of vertebrate animal extinctions on islands, particularly those that lack native mammalian carnivores. In 2001, the American mink (Mustela vison) was recorded for the first time on Navarino Island, in the Cape Horn Biosphere Reserve (55° S) in Chile, representing the southernmost population of mink worldwide. In order to assess its potential impact on native fauna, we studied its diet on Navarino Island, as part of an integrative management program on invasive species. Over a three-year period (2005-2007) we collected 512 scats in semi-aquatic habitats: marine coasts, riparian and lake shores. Overall, the main prey was mammals (37 % biomass), and birds (36 %), followed by fish (24 %). Over the spring and summer, mink consumed significantly more birds, whereas mammals constituted the main prey over the autumn and winter when migratory birds had left the area. Among birds, the mink preyed mainly on adult Passeriformes, followed by Anseriformes and Pelecaniformes, caught as chicks. Among mammals, the exotic muskrat (Ondatra zibethicus) was the most important prey, and together with the native rodent Abrothrix xanthorhinus it accounted for 78 % of the biomass intake. For an integrated management of invasive exotic mammal species on Navarino Island and in the Cape Horn Biosphere Reserve it is important to further research interactions established here among the various introduced mammals, and to initiate immediate control of the mink population in its initial stage of invasion.