Browsing by Author "Novoa, Fernando J."
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- ItemAltered fire regimes modify lizard communities in globally endangered Araucaria forests of the southern Andes(NATURE PORTFOLIO, 2021) Infante, Jose; Novoa, Fernando J.; Ibarra Eliessetch, José Tomás; Melnick, Don J.; Griffin, Kevin L.; Bonacic, CristianWildfire regimes are being altered in ecosystems worldwide. The density of reptiles responds to fires and changes to habitat structure. Some of the most vulnerable ecosystems to human-increased fire frequency are old-growth Araucaria araucana forests of the southern Andes. We investigated the effects of wildfires on the density and richness of a lizard community in these ecosystems, considering fire frequency and elapsed time since last fire. During the 2018/2019 southern summer season, we conducted 71 distance sampling transects to detect lizards in Araucaria forests of Chile in four fire "treatments": (1) unburned control, (2) long-term recovery, (3) short-term recovery, and (4) burned twice. We detected 713 lizards from 7 species. We found that the density and richness of lizards are impacted by wildfire frequency and time of recovery, mediated by the modification of habitat structure. The lizard community varied from a dominant arboreal species (L. pictus) in unburned and long-recovered stands, to a combination of ground-dwelling species (L. lemniscatus and L. araucaniensis) in areas affected by two fires. Araucaria forests provided key habitat features to forest reptiles after fires, but the persistence of these old-growth forests and associated biodiversity may be threatened given the increase in fire frequency.
- Item¿Cómo responden los gremios de aves a los incendios del bosque templado andino de Chile?(2017) Novoa, Fernando J.; Ibarra Eliessetch, José Tomás; Altamirano, Tomás A.; Bonacic Salas, CristianLa frecuencia e intensidad de los incendios forestales están aumentando en el bosque templado. Los incendios modifican el hábitat, pero se desconoce cómo los distintos gremios de aves responden a estos eventos. Evaluamos los efectos de los incendios sobre: la diversidad de aves, gremios alimenticios (GA), gremios de uso de hábitat (GH) y gremios reproductivos (GR) en la zona andina de La Araucanía. Entre 2016-2017, realizamos 80 puntos de conteo y 80 parcelas de hábitat (40 en sitios quemados sólo una vez y 40 en no quemados/control). La riqueza total fue menor en zonas quemadas, no así la abundancia. La riqueza y abundancia de aves granívoras (GA) fue mayor en zonas quemadas. Las aves insectívoras (GA) y aves especialistas de sotobosque (GH) fueron las más disminuidas, tanto riqueza como en abundancia, en zonas quemadas. Las aves que usan cavidades (GR) y las especialistas de árboles grandes (GH) presentaron una menor riqueza en zonas quemadas, pero no una menor abundancia. Nuestros resultados preliminares sugieren que los incendios forestales afectan a los gremios de aves de forma diferencial. Este estudio en proceso evaluará sitios quemados dos veces y los mecanismos relacionados a los cambios en diversidad en los próximos años
- ItemEcosystem engineers show variable impacts on habitat availability for cavity nesters in South American temperate forests(2024) Lima, Cecilia Cuatianquiz; Altamirano, Tomas A.; Jara, Rocio; Price, Edwin R.; Novoa, Fernando J.; Ibarra, Jose TomasEcosystem engineers are organisms that impact their environment and co-existing species by creating or modifying habitats, and thus they play important roles as drivers of community assembly. We examined whether cavity characteristics and/or habitat attributes associated with cavities provided by 4 ecosystem engineers influence the presence of nests of 3 secondary cavity-nesting birds-Aphrastura spinicauda (Thorn-tailed Rayadito), Tachycineta leucopyga (Chilean Swallow), and Troglodytes aedon (Southern House Wren)-and whether these variations influence their reproductive success. We tested this by: (1) assessing nest presence in cavities supplied by ecosystem engineers and (2) quantifying the reproductive success of secondary cavity nesters as a function of cavity characteristics and habitat attributes supplied by ecosystem engineers. Between 2009 and 2022, we recorded 757 cavities in 546 trees in old-growth and second-growth forests in a Global Biodiversity Hotspot in the Andes of southern Chile. Insect/fungi and Pygarrhichas albogularis (White-throated Treerunner) play a key role as the primary producers of cavities. Insect/fungi generated the cavities for 82% of A. spinicauda nests and 95% of T. aedon nests; in contrast, 57% of T. leucopyga nests were cavities excavated by P. albogularis. Characteristics of cavities (size of cavity entrance, volume, and height above ground) were associated with nest presence of secondary cavity nesters and with reproductive success of A. spinicauda and T. aedon. Habitat attributes such as tree density and canopy cover influenced nest presence for A. spinicauda and T. leucopyga, but did not correlate with the reproductive success of any secondary cavity nester. Bamboo density and forest type were related to reproductive success of A. spinicauda and T. aedon. Diameter at Breast Height of trees was related to the reproductive success of T. leucopyga. This study contributes to understanding the importance of various ecosystem engineers for the conservation of secondary cavity-nesting birds in temperate forests and beyond.
- ItemFIRST REPORT OF A MAGELLANIC HORNED OWL (BUBO MAGELLANICUS) NESTING IN A BUILDING BALCONY(2020) Novoa, Fernando J.; Blanco, JoseThe ability of a species to successfully adapt to urban areas is controlled by certain ecological limiting factors. Many owl species have a negative response to urbanization, while there are others that seem to tolerate, or even thrive, in urban environments. Here, we report a nest of the Magellanic Horned Owl (Bubo magellanicus) in a building balcony in a suburban area in the commune of Lo Barnechea, Santiago, Chile. The nest was found in the first week of August 2018, at first bearing a single egg. After 92 days of monitoring, two nestlings successfully abandoned the nest. The use of human-made structures by the Magellanic Horned Owl had not been previously recorded; consequently, this record evidences new nesting opportunities for this owl in urban areas, revealing a change in its reproductive behavior.
- ItemNew record of the rare viscacha Lagidium wolffsohni (Thomas, 1907) in northern Patagonia, Chile(2023) Novoa, Fernando J.; Gomez, Gabriel; Ojeda, Diego; Diez, AndresFew records of Lagidium wolffsohni exist in both Chile and Argentina. Through camera traps, we obtained a new record of L. wolffsohni in northern Patagonia, Chile. We also describe its feeding activity and other behavioral aspects.
- ItemReport on beak abnormalities of some birds of Patagonia(2018) Valdebenito, Jose O.; Grandon-Ojeda, Alexandra; Pantoja-Maggi, Vicente; Novoa, Fernando J.; Gonzalez-Acuna, DanielAvian beaks are complex and highly specialized structures that if altered could hinder many aspects of bird biology. Here, we provide evidence from incidental sightings of 24 birds from 9 species presenting a mild to severe degree of beak abnormality, including species from Passeriformes, Falconiformes, Sphenisciformes, and Charadriiformes, recorded in Chile (2013-2016). The most common alterations corresponded to crossed beaks and excessive elongation of the upper beak (25% each). The Austral Thrush (Turdus falcklandii; n = 11) and Chilean Mockingbird (Mimus thenca; n = 5) were the birds most frequently recorded with abnormalities. With the exception of the Austral Thrush and Magellanic Penguin (Spheniscus magellanicus), all beak abnormalities mentioned here are the first recorded for each species.
- ItemTree-cavity nesting records of the American kestrel (Falco sparverius) in two Andean forest sites of southern Chile(2021) Ibarra Eliessetch, José Tomás; Novoa, Fernando J.; Altamirano, Tomas A.; Vargas, F. HernánEl cernícalo americano (Falco sparverius) nidifica en cavidades o pequeños agujeros protegidos, inclu yendo oquedades de árboles (excavadas o producidas por descomposición), galerías en paredes rocosas o arenosas, entretechos de edificios y cajas nido. La biología reproductiva de esta especie es escasamente conocida en los ecosis temas templados de América del Sur. Entre 2015 y 2020, observamos siete eventos de nidificación del cernícalo en dos cavidades de árboles en un área boscosa del sur de Chile. El tamaño de puesta fue 4˗5 huevos, la incubación duró 28˗29 días, el tamaño de nidada fue 3˗4 polluelos, los polluelos permanecieron 28˗30 días en el nido y el número de volantones fue 2˗4. Nuestras observaciones amplían la comprensión de la historia natural y biología reproductiva del cernícalo en áreas boscosas templadas del sur de Chile.
- ItemTree-cavity survival for biodiversity in temperate forests of South America: A multi-scale approach(Elsevier B.V., 2023) Paratori Girardi, Mariangela Antonieta; Novoa, Fernando J.; Altamirano, Tomás A.; Ibarra Eliessetch, José Tomás; Bonacic, Cristian© 2023 Elsevier B.V.Tree cavities are critical habitat attributes for a diversity of species that use them for reproduction and shelter. Worldwide, their availability has shown an intense decline in forests because of the loss of old-growth stands and the reduction in cavity recruitment. These disturbance processes are influenced by factors occurring across different scales: from cavities to landscapes. We analyzed the survival of 613 cavities in 455 trees in old-growth and second-growth forests over 10 years in Andean temperate forests in southern South America, Chile. Kaplan–Meier and Cox proportional hazards models were used to determine median cavity survival and its influencing factors at the cavity, tree, stand and landscape scales. The median survival was six years. Non-excavated cavities (6 years) survived longer than excavated cavities (4 years), with a significantly longer lifespan in large decaying trees. Cavities’ survival was strongly influenced by cavity- and tree-scale factors, including their origin, the vertical cavity depth, tree decay class, tree branch order and tree diameter class. In old-growth forests, most cavities were found in live decaying trees, while in second-growth forests they were mostly in long-dead trees (snags). We suggest that management should maintain forest structural complexity, retaining dead wood and trees in different stages of decay to permit a continuous supply of substrates over time for the formation of cavities.