José Tomás Ibarra

When Formal and Market-Based Conservation Mechanisms Disrupt Food Sovereignty: Impacts of Community Conservation and Payments for Environmental Services on an Indigenous Community of Oaxaca, Mexico

SUMMARY The impacts of Payments for Environmental Services (PES) and creation of formal Voluntary Conserved Areas (VCAs) on local diets, agricultural practices, subsistence hunting and livelihoods, were assessed in a Chinantec community of southern Mexico. The community has set aside VCAs covering 4 300 ha of its 5 928 ha of communal lands and forests, and has received over S769 245 in PES for protection of 2 822 ha of watersheds roughly overlapping the VCAs. Community members attribute decreased maize and other subsistence crop yields, reduction of area available for agriculture, and shortened fallow cycles to the new conservation policies. Meat consumption has decreased after a hunting ban, accompanied by increases in purchasing meat still consumed. By agreeing to conservation measures that restrict their use of ancestral agricultural land and prohibit hunting, villagers have seen local food security become less stable, leading to greater dependency on external food supplies. Continued strict preservation measures under the guise of community conservation could lead to losses of agrobiodiversity, dietary diversity, hunting skills and associated environmental knowledge. Appropriate application of the precautionary principle is essential to avoid structural displacement of local peoples and to ensure the success of community conservation initiatives.

Invasive American mink Mustela vison in wetlands of the Cape Horn Biosphere Reserve, southern Chile: what are they eating?

This article discusses invasive American mink Mustela vison and its ecological effect in wetlands of the Cape Horn Biosphere Reserve, southern Chile.

Rufous-legged Owl (Strix rufipes) and Austral Pygmy Owl (Glaucidium nanum) stand use in a gradient of disrupted and old growth Andean temperate forests, Chile

We studied how human induced structural changes in forests affect stand use of the Rufous-legged Owl (forest-specialist) and the Austral Pygmy Owl (forest-facultative), in a gradient from lowland disrupted forests to protected Andean forests in Chile. We also tested if the calls of one species influenced the calling behaviour of the other. We detected a total of 34 Rufous-legged Owls and 21 Austral Pygmy Owls during the four seasons. Rufous-legged Owls were found principally in old growth Araucaria-Nothofagus stands (32.4%), and Pygmy Owls in old growth evergreen stands (52.4%). For both species there was a seasonal effect on call response, with a drop in responses in autumn and winter. Our models suggested that Rufous-legged Owls inhabit a more specific range of habitat characteristics than Pygmy Owls. The former selected stands with tall trees, relatively low tree density, and high bamboo density. Pygmy Owls selected stands with tall trees and relatively high tree density. There was no evidence that either species influenced the calling behaviour of the other, suggesting no negative association between use of a territory by the two species. Our results emphasize the importance of structural components of old growth forests for both species, but also the relevance of stands surrounding protected areas. Estudiamos cómo los cambios estructurales en el bosque, inducidos por el ser humano, afectan el uso de hábitat del concón (especialista de bosque) y del chuncho (facultativo de bosque), en un gradiente desde bosques perturbados en zonas bajas hasta bosques andinos protegidos de Chile. También evaluamos si los llamados de una especie influencian el comportamiento de vocalización de la otra. Detectamos un total de 34 concones y 21 chunchos para las cuatro estaciones del año. Los concones fueron registrados principalmente en bosques antiguos de Araucaria-Nothofagus (32.4%), y los chunchos en bosques antiguos siempre-verdes (52.4%). Para ambas especies hubo una disminución de la actividad en otoño e invierno. Nuestros modelos sugirieron que el concón tiene requerimientos de hábitat más específicos que el chuncho. El concón seleccionó bosques con árboles altos y en baja densidad relativa, y una alta densidad de quila. Por su parte, el chuncho seleccionó bosques con árboles altos y en alta densidad relativa. No hubo evidencia de que los llamados de una especie afectaran las respuestas de la otra, sugiriendo que no existe una asociación negativa en el uso de un mismo territorio por ellas. Los resultados enfatizan la importancia de los elementos estructurales de los bosques antiguos para ambas especies pero, a su vez, la relevancia de los bosques periféricos a áreas protegidas.

Beyond species richness: an empirical test of top predators as surrogates for functional diversity and endemism

Using surrogate species to monitor the status of target biodiversity in areas undergoing exceptional habitat loss requires extending the traditional assessment of surrogates for taxonomic diversity to validating surrogates for functional diversity. This validation will be critical to inform about broader ecosystem processes and stability. We compared the surrogacy reliability of the habitat-specialist Rufous-legged Owl (Strix rufipes) and the habitat-generalist Austral Pygmy-Owl (Glaucidium nana), and we examined potential underlying mechanisms for surrogacy relationships in Andean temperate forests, a global biodiversity hotspot in southern Chile. During 2011–2013, we conducted 1,145 owl surveys, 505 vegetation surveys, and 505 avian point-transect surveys across 101 sites comprising a range of conditions from degraded forest habitat to structurally complex old-growth forest stands. The habitat-specialist S. rufipes was a reliable surrogate for all avian biodiversity measures, including avian endemism and functional diversity measures (degree of community specialization and density of large-tree users, understory users, and cavity-nesters). On the contrary, the habitat-generalist G. nana did not function as a surrogate. With increasing occurrence of S. rufipes, the density of target specialized biodiversity (species, guilds, and communities) increased nonlinearly and peaked at the least degraded sites. This specialist aggregation might be driven by stand structural complexity available in older, more stable, forests. These results suggest that management actions tailored to promote occurrence of habitat-specialist owls, such as the S. rufipes, may result in enhanced density of endemic species, specialized communities, and likely ecosystem stability.

Influence of Anthropogenic Disturbances on Stand Structural Complexity in Andean Temperate Forests: Implications for Managing Key Habitat for Biodiversity

Forest attributes and their abundances define the stand structural complexity available as habitat for faunal biodiversity; however, intensive anthropogenic disturbances have the potential to degrade and simplify forest stands. In this paper we develop an index of stand structural complexity and show how anthropogenic disturbances, namely fire, logging, livestock, and their combined presence, affect stand structural complexity in a southern Global Biodiversity Hotspot. From 2011 to 2013, we measured forest structural attributes as well as the presence of anthropogenic disturbances in 505 plots in the Andean zone of the La Araucanía Region, Chile. In each plot, understory density, coarse woody debris, number of snags, tree diameter at breast height, and litter depth were measured, along with signs of the presence of anthropogenic disturbances. Ninety-five percent of the plots showed signs of anthropogenic disturbance (N = 475), with the combined presence of fire, logging, and livestock being the most common disturbance (N = 222; 44% of plots). The lowest values for the index were measured in plots combining fire, logging, and livestock. Undisturbed plots and plots with the presence of relatively old fires (> 70 years) showed the highest values for the index of stand structural complexity. Our results suggest that secondary forests < 70-year post-fire event, with the presence of habitat legacies (e.g. snags and CWD), can reach a structural complexity as high as undisturbed plots. Temperate forests should be managed to retain structural attributes, including understory density (7.2 ± 2.5 # contacts), volume of CWD (22.4 ± 25.8 m3/ha), snag density (94.4 ± 71.0 stems/ha), stand basal area (61.2 ± 31.4 m2/ha), and litter depth (7.5 ± 2.7 cm). Achieving these values will increase forest structural complexity, likely benefiting a range of faunal species in South American temperate forests.

How Can We Teach Our Children if We Cannot Access the Forest? Generational Change in Mapuche Knowledge of Wild Edible Plants in Andean Temperate Ecosystems of Chile

Abstract For many indigenous peoples, the contributions of wild edible plants go well beyond nourishment; they are often also used as dye and medicines, as well as markers of identity. However, historical and contemporary processes of land grabbing, forest loss, acculturation, and lifestyle changes may erode the transmission of plant knowledge to new generations. In this paper, we document 1) the botanical knowledge of wild edible plants and 2) perceived influences on the transmission of this knowledge to younger generations in a Mapuche community in Andean temperate forests, Chile. Thirty-seven people participated in this study. We conducted participant observation, freelists, and informal, photo-elicitation, and semi-structured interviews. A total of 47 wild edibles were recorded (42 plants were determined to species level by participants). Digüeñe (Cyttaria espinosae; Smith’s Index of Saliency, S = 0.82) was the most salient wild edible, followed by changle (Ramaria flava, S = 0.68), maqui (Aristotelia chilensis, S = 0.67), murra (Rubus ulmifolius, S = 0.59), and piñón (Araucaria araucana, S = 0.56). Participants provided detailed information on species seasonality, ecology, and changes in availability over time. Most adult women and elders had a comprehensive knowledge of wild edibles. However, younger generations were not learning what the elders had once learned. The lack of access to forests and the formal school regime were reported as the main factors interrupting the transmission of knowledge. Because Mapuche pedagogy is oral and in situ, land loss and the school regime have left younger generations with few opportunities to engage in these forms of indigenous pedagogy.

Reproductive life-history variation in a secondary cavity-nester across an elevational gradient in Andean temperate ecosystems

ABSTRACT Avian reproductive strategies have been hypothesized to vary with elevation. Shorter breeding seasons due to harsh environmental conditions, and potentially higher predation risks, may reduce clutch sizes at higher elevations, which in some species leads to increased parental care and offspring survival. However, this phenotypically plastic and potentially adaptive response has been documented only in a handful of species in the Northern Hemisphere. For the first time in a southern temperate ecosystem, we studied whether the breeding strategy of a secondary cavity-nester varied along an elevational gradient in Andean temperate forests, Chile. We installed 240 nest-boxes at 260–1,115 m elevation and monitored the breeding activity of 162 nests of Thorn-tailed Rayaditos (Aphrastura spinicauda) over 2 seasons (2010–2012). We included 50 nests from a third season only for recording clutch size and nestlings per clutch. As predicted, the breeding season was shorter in highland forests than in lower elevations, by 28% and 55% over the 2 successive seasons. Although timing of egg laying (1 egg every second day) and incubation period (average = 15 days) did not vary with elevation, we found smaller clutch sizes (average = 4.1 vs. 4.5) and fewer nestlings per clutch (average = 3.5 vs. 4.2) at higher elevations. The extent of parental care, expressed as the duration of the nestling period, was slightly but significantly greater in highland than in lowland forests (22.2 vs. 21.6 days). Despite the longer nestling period at higher elevations, nesting success was lower at high elevations, mainly because of nest predation. Our findings suggest that Thorn-tailed Rayaditos may change to a slower reproductive strategy along elevational gradients. Yet these changes do not appear to compensate for the increased predation rates at higher elevations, calling into question the potential adaptive significance of this strategy.

Spatial patterns over a 24-year period show an increase in native vegetation cover and decreased fragmentation in Andean temperate landscapes, Chile

Changes in landscape pattern were studied in a temperate landscape of the La Araucania Region, Chile. Using aerial photographs from 1983 and 2007, we created land use/land cover maps. We then quantified the changes in composition and configuration by using landscape metrics and an adjacency matrix. By 2007, the dominant land cover had changed from agriculture to native vegetation. Residential areas showed the largest relative increase (670%) and had significant adjacency with native vegetation. The native vegetation increased by 375 ha, but the number of patches decreased by 45% and the mean patch area increased by 124%, which indicated that fragmentation decreased. The growth of tourism and the preference for “natural” spaces by new residents are suggested as the main drivers of this native vegetation recovery. Understanding the process of forest recovery may be helpful for reversing the general trend of forest loss in temperate forests of South America. This research is a first approach in exploring specific cases of native vegetation recovery and decreases in fragmentation in this Global Biodiversity Hotspot. Los cambios en los patrones espaciales fueron estudiados en un paisaje templado de la region de La Araucania, Chile. Se hicieron mapas de cobertura y uso del suelo a partir de fotografias aereas de los anos 1983 y 2007. Los cambios en composicion y configuracion del paisaje se obtuvieron a partir de metricas y una matriz de adyacencia. Para el ano 2007, la cobertura dominante cambio desde agricultura a vegetacion nativa. Las areas residenciales presentaron el mayor aumento porcentual (670%) y una importante relacion de adyacencia con la vegetacion nativa. La vegetacion nativa aumento en 375 ha, pero el numero de parches de esta disminuyo en un 45% y el area media de los parches aumento un 124%, lo que indica una disminucion en la fragmentacion. El incremento del turismo y la preferencia de espacios naturales entre los nuevos residentes del area seria la principal fuerza de cambio detras de la recuperacion de la vegetacion nativa. Considerando la perdida actual de la vegetacion nativa en el area, se hace importante que futuros estudios consideren casos especificos de recuperacion de esta, para asi entender los factores asociados a este proceso. Esta investigacion es una primera aproximacion para entender la recuperacion y disminucion de la fragmentacion de la vegetacion nativa de los ecosistemas templados de America del Sur.Sugarcane cultivation has expanded in south-eastern Brazil in the last decade, mainly for biofuel (ethanol) production. This expansion has occurred on land that was originally covered with pasture and used for livestock production. The purpose of this study is to experimentally determine the impact on runoff and erosion produced by replacing pasture with sugarcane. Runoff plots of 100 m2 were established at a farm in Itirapina, Sao Paulo (SP), Brazil, on a hill with a 9% slope and sandy soil. An 18-year-old pasture and a new sugarcane plantation were studied. The degrees of runoff and erosion were determined after each rain event for the first year of cultivation. From 1,459 mm of annual rainfall, the pasture had lower runoff than the sugarcane cover (40.5 vs 56.1 mm, respectively). Soil erosion under pasture was lower than sugarcane, where the highest values were recorded at the beginning of the rainy season, just after cane planting. In the first year, the results indicate an increase in soil loss of almost 500% for sugarcane compared to pasture, from 0.58 to 2.58 Mg ha-1 year-1 under our experimental conditions. Overall, changing land cover from pasture to sugarcane increases soil erosion. El cultivo de cana de azucar se convirtio en el cultivo de mayor expansion durante los ultimos anos en el sudeste de Brasil, ya que se utiliza como materia prima para la produccion de biocombustible (etanol). En el estado de Sao Paulo, la expansion ocurre principalmente en areas que eran ocupadas por praderas. La sustitucion tiene impactos sobre la escorrentia y la erosion de suelos debido a los cambios en la cobertura y las practicas agricolas. El objetivo del presente estudio es cuantificar experimentalmente el impacto en la escorrentia y erosion de suelos causado por la sustitucion de pradera por cana de azucar. Se construyeron parcelas de escorrentia (100 m2) en una hacienda del municipio de Itirapina-SP, sobre una ladera con 9% de pendiente y suelo arenoso. Una pradera con pastos sembrados hace mas de 18 anos y una plantacion nueva de cana de azucar fueron evaluados, con tres repeticiones para cada cobertura. La escorrentia y erosion de suelos fueron medidas despues de cada evento de lluvia durante el primer ano desde la plantacion de cana de azucar. Se registraron 1.459 mm de precipitaciones, donde pradera presento menos escorrentia que cana de azucar (40,5 vs 56,1 mm respectivamente). La erosion en pradera fue minima comparada con cana de azucar, alcanzando los mayores valores en el inicio de la temporada lluviosa, justo despues de la plantacion. Los resultados indican una perdida de suelo de 0,58 Mg ha-1 ano-1 en pradera a 2,58 Mg ha-1 ano-1 en cana de azucar. El cambio de cobertura desde pradera a cana de azucar aumenta la erosion de suelo.

Maintaining ecosystem resilience: functional responses of tree cavity nesters to logging in temperate forests of the Americas

Logging often reduces taxonomic diversity in forest communities, but little is known about how this biodiversity loss affects the resilience of ecosystem functions. We examined how partial logging and clearcutting of temperate forests influenced functional diversity of birds that nest in tree cavities. We used point-counts in a before-after-control-impact design to examine the effects of logging on the value, range, and density of functional traits in bird communities in Canada (21 species) and Chile (16 species). Clearcutting, but not partial logging, reduced diversity in both systems. The effect was much more pronounced in Chile, where logging operations removed critical nesting resources (large decaying trees), than in Canada, where decaying aspen Populus tremuloides were retained on site. In Chile, logging was accompanied by declines in species richness, functional richness (amount of functional niche occupied by species), community-weighted body mass (average mass, weighted by species densities), and functional divergence (degree of maximization of divergence in occupied functional niche). In Canada, clearcutting did not affect species richness but nevertheless reduced functional richness and community-weighted body mass. Although some cavity-nesting birds can persist under intensive logging operations, their ecosystem functions may be severely compromised unless future nest trees can be retained on logged sites.

Diversidad y singularidad de la avifauna en turberas esfagnosas australes de la Reserva de Biosfera Cabo de Hornos, Chile

Sphagnum -dominated peat bogs that are strongly embedded within the southern temperate forest matrix are increasingly being used for agriculture. Nevertheless, little is known about their biodiversity. Moreover, the remote areas of southern Chile where peat bogs are found, such as the Cape Horn Biosphere Reserve (CHBR, 54-55oS), where birds are the most diverse and best represented group of vertebrates, have not been wellinvestigated. With the aim to broaden this knowledge in the CHBR, we studied the diversity of the avian assemblage in peat bogs on Navarino Island. We compared the composition of avian species between wetlands with and without peat bogs to test if Sphagnum bogs represented a singular habitat for birds in this area. Furthermore, the 37 bird species recorded in these habitats were classified according to guild structure. The community similarity values showed that peat bogs hosted a bird composition that was different from that present in wetlands without Sphagnum , suggesting that peat bogs are a singular type of habitat for birds in the CHBR. The most frequently feeding groups recorded in these wetlands were insectivores (48.7%), followed by omnivores (23.1%). Our results showed that, in contrast to previous studies of birds in peat bogs, these environments constituted a distinct wetland habitat for feeding, reproduction and sheltering for some species in the CHBR. Thus, plans for the conservation and rational use of peat ecosystems should consider the high value of these habitats for biodiversity on a landscape scale, especially for birds of the southernmost extreme of the Americas. Las turberas esfagnosas que se encuentran fuertemente embebidas en la matriz de bosques templados australes, se utilizan de forma creciente en agricultura. Sin embargo, el conocimiento de su biodiversidad es escaso. Mas aun, zonas remotas del sur de Chile donde se encuentran las turberas, como la Reserva de Biosfera Cabo de Hornos (RBCH, 54-55o S), donde las aves constituyen el grupo de vertebrados mas diverso y representativo, aun han sido escasamente estudiadas. Con el objetivo de aportar en su conocimiento en la RBCH, se estudio la diversidad del ensamble de aves en turberas esfagnosas de la isla Navarino. Se exploro si su composicion especifica es igual al de los humedales sin turbera, probando si las turberas constituyen o no un habitat singular para las aves. Tambien se clasifico a las 37 especies de aves registradas en estos habitats de acuerdo a la estructura de gremios. Los valores de similitud taxocenotica senalaron que la composicion de aquellos con turbera difirio de aquellos sin turbera, sugiriendo que este habitat es singular para las aves. El tipo de alimentacion mas frecuente fue la insectivoria (48,7%), seguido por la omnivoria (23,1%). Los resultados muestran que, a diferencia de lo senalado en trabajos previos sobre aves de turberas, estos ambientes constituyen un humedal-habitat singular para la alimentacion, reproduccion y refugio de algunas especies en la RBCH. De esta manera, la conservacion y uso racional de turberas debe considerar el valor que tienen como habitat para la biodiversidad a escala de paisaje, especialmente para las aves del extremo sur americano.