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First steps towards the conservation of the microendemic Patagonian frog Atelognathus nitoi
Abstract
Atelognathus nitoi is a microendemic lepto dactylid frog restricted to the area surrounding the pond Laguna Verde in the Nahuel Huapi National Reserve, north-west Patagonia, Argentina. Its habitat is potentially threatened by a number of anthropogenic and natural factors. The aim of this study was to obtain basic knowledge of the biology and habitat of the species, which would be useful for selecting management measures to ensure its conservation. The area was surveyed during all four seasons in 1996 and 1997 and Laguna Verde was sampled intensively in winter and in summer. Atelognathus nitoi is distributed patchily. The preferred microhabitats of adults and juveniles are the most humid areas of the forest. Reproduction and larval development occurs only in lentic environments. Laguna Verde is the only known permanent water body suitable for reproduction every year. During rainy years reproduction can also take place in temporary ponds. Action towards the conservation of A. Nitoi should be aimed at preserving both the terrestrial and aquatic habitats. Laguna Verde appears to be a key site for the A. Nitoi source population and plays an essential part in the conservation of this species. Zn terrestrial habitats it is vital to preserve the heterogeneity of the lower strata in the forest. The knowledge gained through this study has allowed the authors to suggest protective measures to mitigate or eliminate the impact of certain stressors on the ecology of the species.
... These kinds of environments are locally known as "mallines" (wet meadows) and are complex ecosystems cover by hygrophilous gramineae and different species of rushes, placed in high organic soils (Raffaele 1996;Cuassolo et al. 2011). These wetlands support a great biodiversity of invertebrates and vertebrates which in many cases are endemic species of the region (Ubeda et al. 1999;Chimner et al. 2011;Perotti et al. 2005;Weigandt et al. 2015). Andean wetlands are C reservoir and local estimations has suggested that they contain around 30% of the total ecosystem C in soils and vegetation biomass (Enriquez et al. 2015). ...
Seasonal wetlands are complex ecosystems highly dependent on climatic variation due to their small size and shallowness. Wetlands are carbon (C) reservoirs and the major fraction of the C is in the dissolved phase as part of the dissolved organic matter (DOM). Due to limited information about the characteristics of the DOM regarding source, molecular size/weight and diagenetic state, we aimed to performed an optical DOM characterization of 12 temporary wetlands located in the Argentinean Patagonia. As a result, we found that wetlands located in the austral forest have variable amount of dissolved organic carbon (DOC), ranging from 26.04 to 0.9 mg L⁻¹ in a strong longitudinal gradient from west to east, respectively. The proxy for terrestrial input (a350:DOC) showed high values suggesting an allochthonous origin of the DOM. The DOM molecular size (S275–275) showed that most of the wetlands were characterized by high molecular size/weight DOM. A multivariate analysis (RDA) ordinated the wetlands according to their longitudinal position, in which samples collected at west were characterized by high aromaticity and humification, and low recently produced DOM (low BIX). Meanwhile, at eastern side wetlands are characterized by low DOC, low humic DOM components but increasing values of recently produce DOM (high BIX). This study contributes to understand the interaction between terrestrial and aquatic systems in a pristine region which is increasingly impacted by global climate change.
... Batrachylidae present a total of 12 species, belonging to four genera: Chaltenobatrachus and Hylorina with one species each and Atelognathus and Batrachyla with five species each (Formas 1997, Barrasso & Basso 2019. Hylorina, Atelognathus and Chaltenobatrachus are typical pond-breeding amphibians that breed during spring and summer in lakes, lagoons, ponds or small streams (Barrio 1967, Úbeda et al. 1999, Cisternas et al. 2013, Barrasso et al. 2020. In contrast, Batrachyla species have developed the strategy of laying their eggs in humid soils with embryonic development outside water (Cei 1980, Úbeda 1998, Lobos et al. 2013Jara et al. 2019Jara et al. , 2021. ...
Hylorina sylvatica (Anura: Batrachyidae), or the emerald frog, is a pond-breeding anuran endemic to the austral temperate forests of Chile and Argentina. It is considered a vulnerable species in Argentina, where it has a narrow distribution; records and biological information relating to the frog in this area are scarce. In this study, conducted in 2016, the reproductive parameters of the emerald frog were investigated in detail in a semi-temporary wetland of Northwestern Patagonia, Argentina. During the spring, the wetland was visited weekly in search of calling males, adults and individuals in amplexus. When amplexus was observed, eggs and larvae were collected from among the aquatic vegetation using dip-nets. Egg size and larval stage at hatching were registered. Calling males were registered during the second week of October, and the first couples were observed on 26 October. Three pairs of emerald frogs were captured and placed in enclosures within the wetlands in the afternoon. The males were smaller than the females. After 24 h the number of eggs laid in each enclosure was counted, and the males and females were released. The eggs were kept in each enclosure until hatching. Hatching occurred after 10-14 days in the enclosures. This information contributes to our knowledge of the biology of the emerald frog in Patagonia, Argentina, and is the only information currently available on this species in Nahuel Huapi National Park, where the species breeds in various aquatic environments, from semi-temporary wet meadows to large permanent ponds. ACEPTED MANUSCRIPT
... Hylorina, Atelognathus and Chaltenobatrachus oviposit in the water of lakes, lagoons, ponds or small streams (e.g. Cei, 1965;Barrio, 1967a;Úbeda et al., 1999;Cisternas et al., 2013;Barrasso et al., 2020). Instead, species of Batrachyla lay their eggs on the forest floor where embryos go through prolonged intracapsular periods under parental care, until the rain floods the oviposition site and hatchlings move into the ponds (e.g. ...
The Patagonian rainforest has environmental conditions that may have been appropriate for the evolution of different reproductive strategies in anurans. Despite its low species richness, the endemic family Batrachylidae has a wide diversity of reproductive modes. All species have exotrophic tadpoles, but oviposition sites may vary from lakes/ponds to the forest floor and tree holes. Here we study the embryonic development of five species to explore the morphological diversity and heterochronic shifts related to aquatic vs. terrestrial development. The main differences concern the length of the intracapsular period, morphology at tailbud stage, and gut and hind-limb development. Terrestrial embryos of Batrachyla have some peculiar features also reported in species with endotrophic development, such as yolk-rich eggs, poorly developed gills, precocious development of hind limbs and delayed gut coiling. Furthermore, observations on embryos releasing from the jelly layers with the vitelline membrane intact plus the likely absence of hatching gland cells at hatching stages make it likely that differences can occur in the hatching mechanism. Our results highlight that batrachylids and other neoaustraranans offer an excellent opportunity to investigate the evolution and diversity of reproductive and developmental strategies divergent from aquatic/exotrophic development.
... Las segundas están arraigadas al fondo del cuerpo de agua, y a su vez pueden dividirse en sumergidas, natantes y emergentes. Las macrófitas sumergidas permanecen con todo su cuerpo vegetativo en el interior del agua, sobresaliendo sólo sus flores en la época reproductiva; las natantes o de hojas flotantes, en cambio, poseen hojas que flotan en la superficie del agua, y las radicantes emergentes se caracterizan por presentar una parte de su tallo bajo el agua, con hojas y flores en el aire Al igual que en otros ambientes acuáticos de Patagonia, como lagunas o lagos, las comunidades de macrófitas que se desarrollan en los humedales son muy diversas y con una alta proporción de endemismos, las cuales además, estarían reguladas fundamentalmente por el hidroperíodo (Ubeda & Grigera 1995, Whatley & Cusminsky 1995, Paggi 1999, Ubeda et al. 1999). ...
Los mallines son humedales patagónicos que se caracterizan por sus suelos en permanente anegación, en los cuales pueden generarse pequeños cuerpos de agua denominados pozas, que tienen la capacidad de albergar una vasta diversidad de flora y fauna. Dentro de estos ecosistemas las plantas acuáticas, llamadas macrófitas, se desarrollan y generan distintos hábitos de vida para adaptarse a las condiciones de humedad, además de ser capaces de regular las condiciones físicas y químicas del mallín. Este trabajo tuvo como objetivo relevar y comparar los atributos de la comunidad de macrófitas en función de su distribución en un gradiente oeste-este, el cual genera tres biozonas: bosque, estepa y ecotono. Durante el verano de 2014 se muestrearon un total de 20 mallines de la provincia del Chubut, donde se tomaron datos de abundancia y riqueza de macrófitas, para poder determinar la diversidad de las mismas, además se midieron características fisicoquímicas en las pozas. Para el estudio de las variables ambientales se realizaron análisis de componentes principales (ACP) y análisis de correspondencia canónica (ACC), de manera de vincular los atributos fisicoquímicos con los de la comunidad de macrófitas. Se determinaron un total de 62 taxones, la mayoría correspondiente a las familias Cyperaceae, Poaceae y Ranunculaceae. La mayor diversidad de macrófitas se presentó en los sitios esteparios, evidenciándose así la importancia de esta biozona para la integridad de las comunidades de plantas en la región. La estepa se diferenció del ecotono y el bosque por poseer características como pH alcalino, alta conductividad y valores elevados de fósforo reactivo soluble (PRS). Altos valores de PRS favorecieron la abundancia de plantas, pero a su vez el exceso de clorofila a indicó grados de eutrofización en estas pozas. Las algas fueron las principales indicadoras de degradación ambiental, sin embargo, las macrófitas emergentes también proliferaron con éxito en mallines con exceso de nutrientes. Teniendo en cuenta la importancia de la actividad ganadera en esta provincia, es primordial el conocimiento de las comunidades bióticas y de las características ambientales de los mallines de la zona para el desarrollo de actividades de mitigación y aprovechamiento. Este trabajo se plantea como herramienta en planes de monitoreo de vegetación acuática, y para el uso de bioindicadores de degradación ambiental principalmente en tierras donde la acción antrópica sea extensiva.
... Overwintering tadpoles have been reported in at least 17 genera and 40 species of frogs in the northern and southern hemispheres. Included are: Rana (= Lithobates), Ascaphus, Alytes, Alsodes, Atelognathus, Batrachyla, Hylorina, Calyptocephalella, Chaltenobatrachus, and Polypedates (Martof 1956, Bradford 1983, Díaz and Valencia 1985, Thiesmeier 1992, Úbeda 1998, Úbeda et al. 1999, Hulse et al. 2001, Logares and Úbeda 2004, Cuello and Perotti 2006, Tattersall and Ultsch 2008, Navas et al. 2010, Basso et al. 2011, Hsu et al. 2012. In South America, larval overwintering has only been reported for temperate species such as Alsodes gargola Gallardo, 1970(Logares and Úbeda 2004, A. tumultuosus Veloso et al., 1979, andA. ...
We searched for tadpoles of the streambreeding
frog Odontophrynus occidentalis Berg,
1896 in the Río La Majadita (30°42'47.016'' S,
67°29'44.015'' W; 976 m a.s.l.) in San Juan
Province of the Chaco ecoregion in Argentina in
July 2018. We also undertook subsequent field
trips to the study area to observe the frogs.
Odontophrynus from this region originally was
identified as O. barrioi, but this species was
placed in the synonymy of O. occidentalis by
Martino et al. (2019). We searched the
headwaters of the Río Majadita by day looking
for tadpoles in every potential habitat (e.g., under
rocks and vegetation, and in crevices). We used
dipnets to catch the tadpoles and determine the
developmental stages (Gosner 1960).
... The impact of modifications and alterations caused by human activities as a result of direct (habitat loss) and indirect causes (contamination by chemicals, UV radiation, diseases) on the survival, bioecology, population status, dynamics and diversity of amphibians, began to be referenced in our country with some isolated studies since the mid-70s (Bustoabab et al., 1977;Salibián et al., 1984;Pérez-Coll et al., 1986, among others). However, since the 1990s, research on specific threats, as well as, the synergy of several threats, became a more notable beginning in 2005 (some examples: Rengel and Pisanó, 1991;Salibián, 1992;Lavilla and Buti, 1999;Lajmanovich et al., 1998Lajmanovich et al., , 2002Lajmanovich et al., , 2003aLajmanovich et al., ,b, 2005Lajmanovich et al., , 2010Lajmanovich et al., , 2011Lajmanovich et al., , 2015Lajmanovich et al., , 2017Úbeda et al., 1999;Natale et al., 2000;Lavilla, 2001;Izaguirre et al., 2000Izaguirre et al., , 2001Peltzer et al., , 2004Peltzer et al., , 2010Peltzer et al., , 2013Peltzer et al., , 2015Peltzer et al., , 2017Lajmanovich and Peltzer, 2001;Ponssa et al., 2001;Vaira, 2002;Attademo et al., 2005Attademo et al., , 2007Attademo et al., , 2011Perotti and Dieguez, 2006;Natale et al., 2006;Barrionuevo and Ponssa, 2008;Agostini et al., 2009Agostini et al., , 2012Cuello et al., 2006Junges et al., 2010;Bionda et al., 2011aBionda et al., ,b, 2013Nori et al., 2013;Sánchez et al., 2014;López et al., 2015;Pollo et al., 2016;Akmentins et al., 2015;Curi et al., 2017;Velasco et al., 2018). The studies are distributed in different localities, provinces or regions of the country, however, most of the research referring to the contamination by different substances was developed under laboratory conditions, being insufficient to those analyzed under real conditions of field or in situ. ...
In September 2005, the IUCN Species Survival Commission (SSC) held a summit for the conservation of
amphibians where specialists from around the world agreed that, in addition to the need to document
the declines and extinctions, we need to promote action strategies designed to respond to the global
biodiversity crisis. The outcome of this summit was expressed in the Amphibian Conservation Action
Plan (Gascon et al., 2007) with the recommendation that governments, civil society and the academic community
adopt it and implement the suggested measures.
Since 2007, almost 60 Action Plans have been developed at the national or regional level throughout the world,
including six in South American countries (source: http://www.amphibians.org/publications/national-actionplans/).
In Argentina, there is a growing number of research groups that develop projects related to the conservation
of amphibians with different approaches and objectives. However, a unified national strategy providing an
overview of amphibian conservation actions in the country including a declaration of principles, clearly defined
priorities, and short, medium and long-term goals for the implementation of conservation actions does
not yet exist.
It is certainly of great value to have a comprehensive strategy that provides both the national and provincial
governments with a framework to promote and support conservation programs and a tool that guides research
activities, promotes the creation of information networks, training programs, environmental education, and
outreach and community participation, thereby strengthening efforts to protect the biodiversity of our country.
The Asociación Herpetológica Argentina (AHA) has long led national actions related to the conservation of
amphibians by compiling and publishing the first Categorization of the State of Conservation of the Herpetofauna
of Argentina (Lavilla et al., 2000) And the subsequent update (Vaira et al., 2012). In a similar vein, the
AHA was actively involved in the first Global Amphibian Assessment (GAA) led by IUCN. Specialists convened
during the Argentine Herpetology Congress of Puerto Madryn in 2003 to contribute their knowledge
and validate the data compiled by the IUCN regional coordinator (http://oldredlist.iucnredlist.org/initiatives/
amphibians/process/methods).
As of a result of these activities, the need to design a national strategy for the conservation of amphibians
became evident, not only to evaluate the conservation status of amphibians of Argentina, but also to outline
and address the problems negatively affecting the species and the courses of action that should be taken.
Based on the input from a local network of specialists on various topics, the development of a base document
recommending priority actions was proposed, which could serve as a guideline for the design of conservation
initiatives and a national strategy for the conservation of amphibians in our country. The process included the
creation of a framework to organize the activities to be developed, the implementation of a standard procedure
and the formation of thematic groups of specialists. This initiative was launched in september 2015 during
the XVI Argentine Congress of Herpetology held in the city of San Miguel de Tucumán. There, the general
objectives of the strategy were outlined, and a tentative work schedule was developed, convening the local
specialists who wanted to join this proposal.
This was the starting point for the design and consolidation of specific programs and projects whose goals
and actions could be measured and evaluated periodically. It was then proposed to generate a list of concrete
and realistic goals, with respective actions and performance indicators that would allow their evaluation and
monitoring in the short, medium and long term.
As a result of the process, we finalized this Action Plan for the Conservation of Amphibians of Argentina,which outlines a set of 47 actions that respond to 18 identified problems grouped into 6 components that can
be undertaken in predefined terms. The Plan proposes to execute these actions that experts have considered
as priorities or necessary, however this does not imply that it constitutes a plan that has exhaustively evaluated
all of the problems and possible actions for the conservation of the amphibians of Argentina.
The Plan propose goals and actions that are considered priority to cover the existing information gaps and
face the current and future threats to the conservation of amphibians in our country. It aims to provide clear
guidance on issues that are considered relevant to conservation by identifying and ordering a set of measurable
goals and the respective actions that respond to specific recommendations grouped in the thematic lines
proposed and that can be implemented in the short, medium and long term (1, 3 and 5 years).
Since the fulfillment of the actions is expected to generate changes in the conservation status of the amphibian
species, the Plan includes monitoring of its development, evaluating the progress made in achieving the objectives
according to the established deadlines. This will allow for the incorporation of changes and addition
of new goals during the periodic reviews.
We hope that this Plan will become a starting point for the design and consolidation of inter-institutional and
interdisciplinary programs to guarantee the long-term persistence of the amphibian diversity of Argentina. We
also hope that this document will be relevant for all actors of civil society and that it will increase awareness
of the biodiversity crisis, encouraging them to participate in the proposed action plans.
Finnally, we acknowledge the revision of the english translation of the Plan by Kelsey Neam.
Marcos Vaira
Mauricio S. Akmentins
Esteban O. Lavilla
... Esta especie es microendémica del Parque Nacional Nahuel Huapi, Río Negro con una distribución restringida a una decena de pequeñas lagunas permanentes y temporarias y sus alrededores en un bosque caducifolio de altura entre 1300 y 1550 m s.n.m., en el Cerro Challhuaco (Barrio, 1973;Úbeda et al., 1999a). Posee un número relativamente bajo de huevos (50 a 300), y sin cuidado parental y presenta una Atelognathus nitoi (Barrio 1973). ...
... El impacto de las modificaciones y alteraciones por actividades humanas por causas directas (pérdida de hábitat) e indirectas (contaminación por químicos, radiación UV, enfermedades) en la supervivencia, bioecología, el estatus poblacional, dinámica y diversidad de anfibios, comenzaron a ser referenciadas en nuestro país con algunos estudios aislados desde mediados de la década del ´70 (Bustoabab et al., 1977;Salibián et al., 1984;Pérez-Coll et al., 1986, entre otros). Sin embargo, a partir de la década de los ´90 se incrementaron las investigaciones y aproximaciones sobre el estudio de una amenaza puntual como el sinergismo de varias de éstas, tendencia que fue más notable desde el año 2005 (algunos ejemplos: Rengel y Pisanó, 1991;Salibián, 1992;Lavilla y Buti, 1999;Lajmanovich et al., 1998Lajmanovich et al., , 2002Lajmanovich et al., , 2003aLajmanovich et al., ,b, 2005Lajmanovich et al., , 2010Lajmanovich et al., , 2011Lajmanovich et al., , 2015Lajmanovich et al., , 2017Úbeda et al., 1999;Natale et al., 2000;Lavilla, 2001;Izaguirre et al., 2000Izaguirre et al., , 2001Peltzer et al., , 2004Peltzer et al., , 2010Peltzer et al., , 2013Peltzer et al., , 2015Peltzer et al., , 2017Lajmanovich y Peltzer, 2001;Ponssa et al., 2001;Vaira, 2002;Attademo et al., 2005Attademo et al., , 2007Attademo et al., , 2011Perotti y Dieguez, 2006;Natale et al., 2006;Barrionuevo y Ponssa, 2008;Agostini et al., 2009Agostini et al., , 2012Cuello et al., 2006Junges et al., 2010;Bionda et al., 2011aBionda et al., ,b, 2013Nori et al., 2013;Sánchez et al., 2014;López et al., 2015;Pollo et al., 2016;Akmentins et al., 2015;Curi et al., 2017;Velasco et al., 2018). Los estudios se encuentran distribuidos en distintas localidades, provincias o regiones del país, sin embargo, la mayoría de las investigaciones referidas a la contaminación por distintas sustancias han sido desarrolladas bajo condiciones de laboratorio, siendo insuficientes las analizadas en condiciones reales de campo o in situ. ...
... El impacto de las modificaciones y alteraciones por actividades humanas por causas directas (pérdida de hábitat) e indirectas (contaminación por químicos, radiación UV, enfermedades) en la supervivencia, bioecología, el estatus poblacional, dinámica y diversidad de anfibios, comenzaron a ser referenciadas en nuestro país con algunos estudios aislados desde mediados de la década del ´70 (Bustoabab et al., 1977;Salibián et al., 1984;Pérez-Coll et al., 1986, entre otros). Sin embargo, a partir de la década de los ´90 se incrementaron las investigaciones y aproximaciones sobre el estudio de una amenaza puntual como del sinergismo de varias de éstas, tendencia que fue más notable desde el año 2005 (algunos ejemplos: Rengel y Pisanó, 1991;Salibián, 1992;Lavilla y Buti, 1999;Lajmanovich et al., 1998Lajmanovich et al., , 2002Lajmanovich et al., , 2003aLajmanovich et al., ,b, 2005Lajmanovich et al., , 2010Lajmanovich et al., , 2011Lajmanovich et al., , 2015Lajmanovich et al., , 2017Úbeda et al., 1999;Natale et al., 2000;Lavilla, 2001;Izaguirre et al., 2000Izaguirre et al., , 2001Peltzer et al., , 2004Peltzer et al., , 2010Peltzer et al., , 2013Peltzer et al., , 2015Peltzer et al., , 2017Lajmanovich y Peltzer, 2001;Ponssa et al., 2001;Vaira, 2002;Attademo et al., 2005Attademo et al., , 2007Attademo et al., , 2011Perotti y Dieguez, 2006;Natale et al., 2006;Barrionuevo y Ponssa, 2008;Agostini et al., 2009Agostini et al., , 2012Cuello et al., 2006Junges et al., 2010;Bionda et al., 2011aBionda et al., ,b, 2013Nori et al., 2013;Sánchez et al., 2014;López et al., 2015;Pollo et al., 2016;Akmentins et al., 2015;Curi et al., 2017;Velasco et al., 2018). Los estudios se encuentran distribuidos en distintas localidades, provincias o regiones del país, sin embargo, la mayoría de las investigaciones referidas a la contaminación por distintas sustancias han sido desarrolladas bajo condiciones de laboratorio, siendo insuficientes las analizadas en condiciones reales de campo o in situ. ...
El público general desconoce que la República Argentina es uno de los países con mayor diversidad de anfibiosen América Latina, presentando unas 175 especies, con una gran proporción de endemismos, ciclos de vidaúnicos y adaptaciones fisiológicas y/o comportamentales a ambientes extremos (entre otras). La visión generales que la diversidad de anfibios se limita solo a sapos, ranas (inclusive, es común que sean consideradas elfemenino de los sapos) y escuerzos. Uno de los aspectos más problemáticos a la hora de generar interés en lacomunidad sobre la conservación de anfibios, es el desconocimiento del rol que cumplen en los ecosistemas, asícomo también los beneficios que este grupo puede proveer. También, abundan en el saber popular leyendas omitos sobre la peligrosidad o características nocivas de los anfibios. En gran parte, esta falta de conocimiento sebasa en la dificultad que enfrenta el público general, educadores y/o interesados en la naturaleza para acceder ainformación de calidad y con un lenguaje simple sobre la fauna de anfibios. Bajo la premisa ?no se conserva loque no se conoce? es que se debería lograr generar información, sobre la diversidad de especies de anfibios de laArgentina y sus problemáticas de conservación, que involucre un lenguaje claro y resulte accesible a todo tipode público.Por otra parte, los museos, privados o estatales (nacionales, provinciales y municipales), son los lugares máscomunes donde el público general concurre a interiorizarse sobre las ciencias naturales. Aunque los anfibiosrara vez ocupan lugares preponderantes dentro de las exposiciones permanentes o temporales, esta tendenciase ha revertido en los últimos años, principalmente por iniciativas como ?La Noche de los Museos?, dondelos investigadores pueden comunicar directamente al público concurrente la información sobre sus líneas deinvestigación y organismos de estudio.
... El impacto de las modificaciones y alteraciones por actividades humanas por causas directas (pérdida de hábitat) e indirectas (contaminación por químicos, radiación UV, enfermedades) en la supervivencia, bioecología, el estatus poblacional, dinámica y diversidad de anfibios, comenzaron a ser referenciadas en nuestro país con algunos estudios aislados desde mediados de la década del ´70 (Bustoabab et al., 1977;Salibián et al., 1984;Pérez-Coll et al., 1986, entre otros). Sin embargo, a partir de la década de los ´90 se incrementaron las investigaciones y aproximaciones sobre el estudio de una amenaza puntual como del sinergismo de varias de éstas, tendencia que fue más notable desde el año 2005 (algunos ejemplos: Rengel y Pisanó, 1991;Salibián, 1992;Lavilla y Buti, 1999;Lajmanovich et al., 1998Lajmanovich et al., , 2002Lajmanovich et al., , 2003aLajmanovich et al., ,b, 2005Lajmanovich et al., , 2010Lajmanovich et al., , 2011Lajmanovich et al., , 2015Lajmanovich et al., , 2017Úbeda et al., 1999;Natale et al., 2000;Lavilla, 2001;Izaguirre et al., 2000Izaguirre et al., , 2001Peltzer et al., , 2004Peltzer et al., , 2010Peltzer et al., , 2013Peltzer et al., , 2015Peltzer et al., , 2017Lajmanovich y Peltzer, 2001;Ponssa et al., 2001;Vaira, 2002;Attademo et al., 2005Attademo et al., , 2007Attademo et al., , 2011Perotti y Dieguez, 2006;Natale et al., 2006;Barrionuevo y Ponssa, 2008;Agostini et al., 2009Agostini et al., , 2012Cuello et al., 2006Junges et al., 2010;Bionda et al., 2011aBionda et al., ,b, 2013Nori et al., 2013;Sánchez et al., 2014;López et al., 2015;Pollo et al., 2016;Akmentins et al., 2015;Curi et al., 2017;Velasco et al., 2018). Los estudios se encuentran distribuidos en distintas localidades, provincias o regiones del país, sin embargo, la mayoría de las investigaciones referidas a la contaminación por distintas sustancias han sido desarrolladas bajo condiciones de laboratorio, siendo insuficientes las analizadas en condiciones reales de campo o in situ. ...
... El impacto de las modificaciones y alteraciones por actividades humanas por causas directas (pérdida de hábitat) e indirectas (contaminación por químicos, radiación UV, enfermedades) en la supervivencia, bioecología, el estatus poblacional, dinámica y diversidad de anfibios, comenzaron a ser referenciadas en nuestro país con algunos estudios aislados desde mediados de la década del ´70 (Bustoabab et al., 1977;Salibián et al., 1984;Pérez-Coll et al., 1986, entre otros). Sin embargo, a partir de la década de los ´90 se incrementaron las investigaciones y aproximaciones sobre el estudio de una amenaza puntual como del sinergismo de varias de éstas, tendencia que fue más notable desde el año 2005 (algunos ejemplos: Rengel y Pisanó, 1991;Salibián, 1992;Lavilla y Buti, 1999;Lajmanovich et al., 1998Lajmanovich et al., , 2002Lajmanovich et al., , 2003aLajmanovich et al., ,b, 2005Lajmanovich et al., , 2010Lajmanovich et al., , 2011Lajmanovich et al., , 2015Lajmanovich et al., , 2017Úbeda et al., 1999;Natale et al., 2000;Lavilla, 2001;Izaguirre et al., 2000Izaguirre et al., , 2001Peltzer et al., , 2004Peltzer et al., , 2010Peltzer et al., , 2013Peltzer et al., , 2015Peltzer et al., , 2017Lajmanovich y Peltzer, 2001;Ponssa et al., 2001;Vaira, 2002;Attademo et al., 2005Attademo et al., , 2007Attademo et al., , 2011Perotti y Dieguez, 2006;Natale et al., 2006;Barrionuevo y Ponssa, 2008;Agostini et al., 2009Agostini et al., , 2012Cuello et al., 2006Junges et al., 2010;Bionda et al., 2011aBionda et al., ,b, 2013Nori et al., 2013;Sánchez et al., 2014;López et al., 2015;Pollo et al., 2016;Akmentins et al., 2015;Curi et al., 2017;Velasco et al., 2018). Los estudios se encuentran distribuidos en distintas localidades, provincias o regiones del país, sin embargo, la mayoría de las investigaciones referidas a la contaminación por distintas sustancias han sido desarrolladas bajo condiciones de laboratorio, siendo insuficientes las analizadas en condiciones reales de campo o in situ. ...
... El impacto de las modificaciones y alteraciones por actividades humanas por causas directas (pérdida de hábitat) e indirectas (contaminación por químicos, radiación UV, enfermedades) en la supervivencia, bioecología, el estatus poblacional, dinámica y diversidad de anfibios, comenzaron a ser referenciadas en nuestro país con algunos estudios aislados desde mediados de la década del ´70 (Bustoabab et al., 1977;Salibián et al., 1984;Pérez-Coll et al., 1986, entre otros). Sin embargo, a partir de la década de los ´90 se incrementaron las investigaciones y aproximaciones sobre el estudio de una amenaza puntual como del sinergismo de varias de éstas, tendencia que fue más notable desde el año 2005 (algunos ejemplos: Rengel y Pisanó, 1991;Salibián, 1992;Lavilla y Buti, 1999;Lajmanovich et al., 1998Lajmanovich et al., , 2002Lajmanovich et al., , 2003aLajmanovich et al., ,b, 2005Lajmanovich et al., , 2010Lajmanovich et al., , 2011Lajmanovich et al., , 2015Lajmanovich et al., , 2017Úbeda et al., 1999;Natale et al., 2000;Lavilla, 2001;Izaguirre et al., 2000Izaguirre et al., , 2001Peltzer et al., , 2004Peltzer et al., , 2010Peltzer et al., , 2013Peltzer et al., , 2015Peltzer et al., , 2017Lajmanovich y Peltzer, 2001;Ponssa et al., 2001;Vaira, 2002;Attademo et al., 2005Attademo et al., , 2007Attademo et al., , 2011Perotti y Dieguez, 2006;Natale et al., 2006;Barrionuevo y Ponssa, 2008;Agostini et al., 2009Agostini et al., , 2012Cuello et al., 2006Junges et al., 2010;Bionda et al., 2011aBionda et al., ,b, 2013Nori et al., 2013;Sánchez et al., 2014;López et al., 2015;Pollo et al., 2016;Akmentins et al., 2015;Curi et al., 2017;Velasco et al., 2018). Los estudios se encuentran distribuidos en distintas localidades, provincias o regiones del país, sin embargo, la mayoría de las investigaciones referidas a la contaminación por distintas sustancias han sido desarrolladas bajo condiciones de laboratorio, siendo insuficientes las analizadas en condiciones reales de campo o in situ. ...
... El impacto de las modificaciones y alteraciones por actividades humanas por causas directas (pérdida de hábitat) e indirectas (contaminación por químicos, radiación UV, enfermedades) en la supervivencia, bioecología, el estatus poblacional, dinámica y diversidad de anfibios, comenzaron a ser referenciadas en nuestro país con algunos estudios aislados desde mediados de la década del ´70 (Bustoabab et al., 1977;Salibián et al., 1984;Pérez-Coll et al., 1986, entre otros). Sin embargo, a partir de la década de los ´90 se incrementaron las investigaciones y aproximaciones sobre el estudio de una amenaza puntual como del sinergismo de varias de éstas, tendencia que fue más notable desde el año 2005 (algunos ejemplos: Rengel y Pisanó, 1991;Salibián, 1992;Lavilla y Buti, 1999;Lajmanovich et al., 1998Lajmanovich et al., , 2002Lajmanovich et al., , 2003aLajmanovich et al., ,b, 2005Lajmanovich et al., , 2010Lajmanovich et al., , 2011Lajmanovich et al., , 2015Lajmanovich et al., , 2017Úbeda et al., 1999;Natale et al., 2000;Lavilla, 2001;Izaguirre et al., 2000Izaguirre et al., , 2001Peltzer et al., , 2004Peltzer et al., , 2010Peltzer et al., , 2013Peltzer et al., , 2015Peltzer et al., , 2017Lajmanovich y Peltzer, 2001;Ponssa et al., 2001;Vaira, 2002;Attademo et al., 2005Attademo et al., , 2007Attademo et al., , 2011Perotti y Dieguez, 2006;Natale et al., 2006;Barrionuevo y Ponssa, 2008;Agostini et al., 2009Agostini et al., , 2012Cuello et al., 2006Junges et al., 2010;Bionda et al., 2011aBionda et al., ,b, 2013Nori et al., 2013;Sánchez et al., 2014;López et al., 2015;Pollo et al., 2016;Akmentins et al., 2015;Curi et al., 2017;Velasco et al., 2018). Los estudios se encuentran distribuidos en distintas localidades, provincias o regiones del país, sin embargo, la mayoría de las investigaciones referidas a la contaminación por distintas sustancias han sido desarrolladas bajo condiciones de laboratorio, siendo insuficientes las analizadas en condiciones reales de campo o in situ. ...
... El impacto de las modificaciones y alteraciones por actividades humanas por causas directas (pérdida de hábitat) e indirectas (contaminación por químicos, radiación UV, enfermedades) en la supervivencia, bioecología, el estatus poblacional, dinámica y diversidad de anfibios, comenzaron a ser referenciadas en nuestro país con algunos estudios aislados desde mediados de la década del ´70 (Bustoabab et al., 1977;Salibián et al., 1984;Pérez-Coll et al., 1986, entre otros). Sin embargo, a partir de la década de los ´90 se incrementaron las investigaciones y aproximaciones sobre el estudio de una amenaza puntual como del sinergismo de varias de éstas, tendencia que fue más notable desde el año 2005 (algunos ejemplos: Rengel y Pisanó, 1991;Salibián, 1992;Lavilla y Buti, 1999;Lajmanovich et al., 1998Lajmanovich et al., , 2002Lajmanovich et al., , 2003aLajmanovich et al., ,b, 2005Lajmanovich et al., , 2010Lajmanovich et al., , 2011Lajmanovich et al., , 2015Lajmanovich et al., , 2017Úbeda et al., 1999;Natale et al., 2000;Lavilla, 2001;Izaguirre et al., 2000Izaguirre et al., , 2001Peltzer et al., 2003Peltzer et al., , 2004Peltzer et al., , 2006Peltzer et al., , 2008Peltzer et al., , 2010Peltzer et al., , 2013Peltzer et al., , 2015Peltzer et al., , 2017Lajmanovich y Peltzer, 2001;Ponssa et al., 2001;Vaira, 2002;Attademo et al., 2005Attademo et al., , 2007Attademo et al., , 2011Perotti y Dieguez, 2006;Natale et al., 2006;Barrionuevo y Ponssa, 2008;Agostini et al., 2009Agostini et al., , 2012Cuello et al., 2006Cuello et al., , 2009Junges et al., 2010;Bionda et al., 2011aBionda et al., ,b, 2013Nori et al., 2013;Sánchez et al., 2014;López et al., 2015;Pollo et al., 2016;Akmentins et al., 2015;Curi et al., 2017;Velasco et al., 2018). Los estudios se encuentran distribuidos en distintas localidades, provincias o regiones del país, sin embargo, la mayoría de las investigaciones referidas a la contaminación por distintas sustancias han sido desarrolladas bajo condiciones de laboratorio, siendo insuficientes las analizadas en condiciones reales de campo o in situ. ...
... El impacto de las modificaciones y alteraciones por actividades humanas por causas directas (pérdida de hábitat) e indirectas (contaminación por químicos, radiación UV, enfermedades) en la supervivencia, bioecología, el estatus poblacional, dinámica y diversidad de anfibios, comenzaron a ser referenciadas en nuestro país con algunos estudios aislados desde mediados de la década del ´70 (Bustoabab et al., 1977;Salibián et al., 1984;Pérez-Coll et al., 1986, entre otros). Sin embargo, a partir de la década de los ´90 se incrementaron las investigaciones y aproximaciones sobre el estudio de una amenaza puntual como el sinergismo de varias de éstas, tendencia que fue más notable desde el año 2005 (algunos ejemplos: Rengel y Pisanó, 1991;Salibián, 1992;Lavilla y Buti, 1999;Lajmanovich et al., 1998Lajmanovich et al., , 2002Lajmanovich et al., , 2003aLajmanovich et al., ,b, 2005Lajmanovich et al., , 2010Lajmanovich et al., , 2011Lajmanovich et al., , 2015Lajmanovich et al., , 2017Úbeda et al., 1999;Natale et al., 2000;Lavilla, 2001;Izaguirre et al., 2000Izaguirre et al., , 2001Peltzer et al., , 2004Peltzer et al., , 2010Peltzer et al., , 2013Peltzer et al., , 2015Peltzer et al., , 2017Lajmanovich y Peltzer, 2001;Ponssa et al., 2001;Vaira, 2002;Attademo et al., 2005Attademo et al., , 2007Attademo et al., , 2011Perotti y Dieguez, 2006;Natale et al., 2006;Barrionuevo y Ponssa, 2008;Agostini et al., 2009Agostini et al., , 2012Cuello et al., 2006Junges et al., 2010;Bionda et al., 2011aBionda et al., ,b, 2013Nori et al., 2013;Sánchez et al., 2014;López et al., 2015;Pollo et al., 2016;Akmentins et al., 2015;Curi et al., 2017;Velasco et al., 2018). Los estudios se encuentran distribuidos en distintas localidades, provincias o regiones del país, sin embargo, la mayoría de las investigaciones referidas a la contaminación por distintas sustancias han sido desarrolladas bajo condiciones de laboratorio, siendo insuficientes las analizadas en condiciones reales de campo o in situ. ...
El Plan de Acción para la Conservación de los Anfibios de la República Argentina que reseña un conjunto de 47 acciones que responden a 18 problemáticas identificadas,
agrupadas en 6 componentes que pueden acometerse en plazos preestablecidos. El Plan propone ejecutar estas acciones que los especialistas convocados han considerado prioritarias o necesarias, aunque ello no implica que constituya un Plan que haya agotado y evaluado todos los problemas y acciones posibles para la conservación de los anfibios de la República Argentina.
... Esta especie es microendémica del Parque Nacional Nahuel Huapi, Río Negro con una distribución restringida a una decena de pequeñas lagunas permanentes y temporarias y sus alrededores en un bosque caducifolio de altura entre 1300 y 1550 m s.n.m., en el Cerro Challhuaco (Barrio, 1973;Úbeda et al., 1999a). Posee un número relativamente bajo de huevos (50 a 300), y sin cuidado parental y presenta una Atelognathus nitoi (Barrio 1973). ...
... Overwintering tadpoles were reported for several species from the Northern and Southern Hemispheres, including the genera Rana (= Lithobates), Ascaphus, Alytes, Alsodes, Atelognathus, Batrachyla, Hylorina, Calyptocephalella, Chaltenobatrachus and Polypedates (Martof, 1956;Bradford, 1983;Díaz and Valencia, 1985;Thiesmeier, 1992;Úbeda, 1998;Úbeda et al., 1999;Hulse, McCoy and Censky, 2001;Logares andÚbeda, 2004, 2006;Cuello and Perotti, 2006;Tattersall and Ultsch, 2008;Navas et al., 2010;Basso et al., 2011;Hsu, Kam and Fellers, 2012). Instead, a long larval development that includes more than one winter was demonstrated only for Ascaphus montanus and A. truei (Brown, 1990;Bury and Adams, 1999) in North America. ...
Overwintering is an anuran strategy to survive in cold-temperate climates. Those aquatic species that withstand harsh conditions and short growing seasons are candidates for having long larval periods. Prolonged larval development, which includes overwintering for more than two years, has been reported for North-American and Euro-Asiatic species, but this strategy has been poorly studied in the Southern Hemisphere. Alsodes pehuenche is an endemic frog from the high Andes mountains of Argentina and Chile, recently categorized as Endangered by the Asociación Herpetológica Argentina (AHA) and as Critically Endangered by the International Union for Conservation of Nature (IUCN). We studied egg laying in this species and its larval development by marking tadpoles with elastomers. We found that eggs are laid in clumps at the beginning of summer. The larval cycle includes four winters, although a fifth winter should not be ruled out. This is the first study that demonstrates a long larval development (four winters) in South-American species and has important implications for conservation biology.
... 31 On the other hand, Lake Verde, as most mountain lakes, freezes every year for several months and displays either inverse stratification or homogeneous temperature profiles in the water column. 23,32 Although the actual radiation doses experienced by the copepod populations would be difficult to quantify, it is likely that they do differ between the two lakes, being likely higher in the mountain lake Verde, due to differences in altitude, light penetration and the lack of a depth refuge. 2,23 In addition to differences in the physical environment, the two lakes have different trophic structures: most notably, fish (i.e., visual planktivores) are only present in Lake Morenito. ...
The bio-accumulation of mycosporine-like amino acids (MAAs) is common in planktonic copepods that inhabit environments exposed to high levels of solar radiation. MAAs accumulation in copepods can be affected both by extrinsic (environmental) and intrinsic factors (local adaptation, genotype, etc.). Laboratory experiments were performed to study the bio-accumulation of MAAs in two geographically-isolated populations of Boeckella gracilipes from a mountain and a piedmont lake of North Patagonia. We performed two series of 10-day incubations of B. gracilipes from the different lakes applying two radiation conditions (PAR + UVR and darkness), at five different temperatures (5 to 20 °C) and providing a MAA-free flagellate as food. We assumed that differences in final MAAs concentrations between copepod populations should be exclusively due to environmental factors, and that any difference in the patterns of MAAs accumulation should exclusively arise from differences in MAAs concentration at the time of collection. MAAs concentration was three fold higher in B. gracilipes from Lake Verde than in copepods from the Lake Morenito. The MAAs suite was dominated (∼90%) by a combination of porphyra-334 and mycosporine-glycine in copepods from Lake Verde, and porphyra-334 and MAA-332 in those from Lake Morenito. Two exclusive MAA compounds were identified, mycosporine-glycine in copepods from Lake Verde and shinorine in the copepod population from Lake Morenito. Laboratory experiments showed that: (i) exposure to PAR + UVR stimulated the accumulation of MAAs in both copepod populations; (ii) temperature affected the response of MAAs and, remarkably, low temperatures stimulated MAAs accumulation even in dark incubations, (iii) the response to radiation and temperature in MAAs accumulation was more pronounced in the population with low initial MAAs than in the population with high initial MAAs concentrations. The differences in intrinsic factors between B. gracilipes populations, such as local adaptation to contrasting UV and temperature scenarios, among others, appear to play an important role in determining levels and patterns of MAAs accumulation in B. gracilipes.
... Esta especie es microendémica del Parque Nacional Nahuel Huapi, Río Negro con una distribución restringida a una decena de pequeñas lagunas permanentes y temporarias y sus alrededores en un bosque caducifolio de altura entre 1300 y 1550 m s.n.m., en el Cerro Challhuaco (Barrio, 1973;Úbeda et al., 1999a). Posee un número relativamente bajo de huevos (50 a 300), y sin cuidado parental y presenta una Atelognathus nitoi (Barrio 1973). ...
... The ways to address the impact of pine plantations at the regional scale were: the replacement of biodiversity key zones by plantations, and the level of occupancy or fragmentation of the natural area with them. Priorities areas for conservation were determined through workshops (Bran et al. 1999;Vila et al. 1999;Rusch et al. 2008), based on published (Chehébar et al. 1986;Monjeau et al. 1994;Aizen and Escurra 1998;Úbeda et al. 1999;Marcelli and Gallo 2000;Prémoli and Kitzberger 2000) and unpublished works of scientists from the region. Those sites were important for their high diversity, level of endemism, presence of endangered species, unique processes or ensembles. ...
In NW Patagonia region, Argentina, South-America, there are about 70,000 ha of planted forests replacing from native forests to grasslands with different degrees of deterioration due to previous land use. Although forestry development has been quite slow in this region compared to other regions of the country, it is expected that this activity will be increasing in the future due to provincial and national government policies of forestry incentives. In general, only scarce information is available about the environmental impact of forestation in the region. Our objective was to bring together the knowledge about the changes in biodiversity, water cycle and water resources, soil characteristics and the risk of invasion of introduced exotic fast-growing coniferous species on native ecosystems. The analyses revealed that the greatest changes in biodiversity, water consumption and invasion risk occurred when the introduction of trees was in grasslands compared to forest or shrublands. However, from our results we can conclude that, at the current developmental stage of forestry activity in Patagonia, the negative environmental impact is very low or even nil, with the positive impacts –economic and social-possibly being higher and leading to a more positive balance as a whole. However, we recognize that potential negative impacts, whose magnitude will depend on several aspects discussed in the paper, could increase in the future in relation to the expansion of the forested areas. With the available information we can then formulate prescriptions and management strategies for exotic systems, in order to guarantee the long term sustainability of the activity. In this regard, we have the opportunity of developing a sustainable production activity from the very beginning.
... Together with other rare endemic species (e.g. Úbeda et al. 2002), S. carbonensis is a focal species of a critical area of conservation priority of Nahuel Huapi National Park, Argentina. Continued study of the causes of rarity will also improve the theoretical and practical foundations of conservation programs of other threatened species (Gaston 1994). ...
We tested the hypothesis that South Andean populations of the highly polymorphic and mostly Northern Hemisphere perennial forb Cerastium arvense L. show ecotypic variation along distinct habitats. We compared differences in morphology and flowering phenology among six natural populations occurring in different environments. Genetic differences were analyzed by a common-garden experiment and isozyme electrophoresis. Several of the morphological differences observed in the field were maintained after more than a year of cultivation in the common garden (e.g., plant height and leaf width). Mean tests and multivariate analyses on morphological traits generally distinguished high-elevation populations from the rest, and a similar grouping of populations was obtained from isozyme data at 10 loci. Cerastium arvense had genetic polymorphism levels of >50% in all populations and an average genetic diversity (HT = 0.254) of which approximately 20% was distributed among populations. These marked genetic differences are probably maintained by restricted gene flow due to variation in flowering time. Morphological and genetic differences suggest ecotypic variation in C. arvense in the southern Andes, which seems to have originated by disruptive selective pressures in different environments and the effect of genetic drift in response to the extreme climatic changes occurring during the Pleistocene.Key words: common-garden experiment, ecotypic variation, elevation and precipitation, genetic diversity, Patagonian Andes, phenology.
... Together with other rare endemic species (e.g. Úbeda et al. 2002), S. carbonensis is a focal species of a critical area of conservation priority of Nahuel Huapi National Park, Argentina. Continued study of the causes of rarity will also improve the theoretical and practical foundations of conservation programs of other threatened species (Gaston 1994). ...
We studied morphological variation, reproductive biology and genetic structure of Senecio carbonensis, a narrow endemic from high elevations of the southern Andes, and compared it to Senecio peteroanus, a closely related widespread congeneric species. Using ANOVAs and discriminant analysis we showed that populations of S. carbonensis were more similar to each other in their morphology, had comparatively limited reproductive capacity and presented lower plant density and more reduced plant cover than populations of S. peteroanus. Similar high genetic variation was found at the population and species level in both species, based on isozyme variation at 14 and 11 putative gene loci that were resolved in S. carbonensis and S. peteroanus, respectively. The two species were genetically distinct. However, the small genetic distance between populations of each species suggests that either they were recently founded and that genetic drift did not have time to promote divergence, or that its effects are masked by significant current gene flow. These results show that ecological and reproductive characteristics of S. carbonensis may limit its extension and abundance. In contrast, high genetic variation at the population level is probably favored by self-incompatibility. Despite the restricted geographical distribution and low plant density of S. carbonensis populations, genetic characteristics do not seem to be limiting their long-term persistence. This information suggests that populations of S. carbonensis are not at risk of extinction as a result of genetic factors, although it is important to study and monitor population dynamics to further assess the degree of recruitment through time.
El objetivo principal de este Manual es el desarrollo de un compendio de técnicas y protocolos estándares para el inventario y monitoreo de poblaciones de anfibios, actualizado con los procedimientos, herramientas y técnicas de análisis más recientes y adaptado a las condiciones y realidades nacionales. Su contenido está destinado a ayudar a superar algunas de las dificultades que se pueden enfrentar al configurar un programa de inventario y monitoreo para anfibios. Pretendemos brindar una orientación práctica sobre cómo diseñar y llevar a cabo estudios que puedan servir para múltiples aplicaciones más allá de las necesidades de un proyecto particular. En este manual compilamos las experiencias y consejos de numerosos especialistas sobre diferentes temáticas que pudieran permitir a los lectores y usuarios de este manual obtener la mayor cantidad y calidad de datos durante la realización de futuros proyectos de investigación relacionados con estas temáticas.
Anuran amphibians of the Andean-Patagonian forest show a
wide variety of adaptations to different aquatic environments
and regional environmental conditions. These adaptations include
particularities in their life cycles, such as that all or
most of the cycle occur out of water. This work summarizes information
about the life cycle of the anuran Batrachyla
taeniata, or banded wood frog, which reproduces from midsummer
to midautumn, laying eggs out of the water, in the
moist soil, where they are incubated. Particularly our studies
were carried out in the forest of the Llao Llao Municipal Park,
where the species lives in different aquatic environments.
Tadpoles hatch when autumn rains cause an increase in water
level or during flooding of a wetland, in a state of development
that allows them to feed immediately and continue
their growth in the water at low temperatures for several
months before arrival of spring. Through field observations
and incubation of eggs under laboratory conditions we were
able to determine the high dependence that exists between
precipitation, temperature and the effective development of
eggs and their subsequent hatching. Finally, we point out the
potential effects of climate change on a regional scale and
how this phenomenon could affect the survival of this common
species of rainforests of the Nahuel Huapi National Park.
The seven species of southern South American frogs belonging to the genus Atelognathus occur in a variety of environments, such as the extra‐Andean Patagonian steppe, temperate Nothofagus forests, and ecotonal zones between them in Argentina and Chile. Most species are known only from their type localities and sometimes also nearby surrounding areas. The temperate forests and the ecotones are inhabited by A. nitoi, A. ceii, and A. salai. The taxonomic status of these species is evaluated herein using morphological characters and DNA sequences of cytochrome b, control region, and recombination‐activating protein 1 gene. In addition, we reevaluate the diagnostic characters proposed in the original description of each species. Contrary to what expected, we found very low genetic divergence among taxa. Both DNA sequence data and morphological characters did not support the current taxonomy arrangement within Atelognathus. We suggest the recognition of only A. nitoi inhabiting the temperate forests, with A. ceii and A. salai being junior synonyms. This species putatively expanded in a northwards direction across Patagonia, undergoing a recent demographic expansion from southern populations. We evaluated the taxonomic status of Atelognathus nitoi, A. ceii, A. salai, and one unnamed population from Lago General Vintter using morphological characters and DNA sequences of cyt b, CR, and RAG1. Both DNA sequence data and morphological characters did not support the current taxonomy of the Atelognathus species studied. We found a single species under a geographic expansion process from southern populations, and we suggest that A. ceii and A. salai are junior synonyms of Atelognathus nitoi.
anurans living along the andes cordillera exploit several thermal environments that vary with altitude and latitude. studies on moderate and high-elevation tropical species suggest co-adaptation between thermal ecology and thermal physiology. our objective was to test whether this is the case for three patagonian anuran species. We focused on larval stages and analyzed critical maximum and minimum temperatures granting survivorship. The species studied were Alsodes gargola, Pleurodema bufoninum and Rhinella spinulosa papillosa. Alsodes gargola lives primarily in high-elevation lakes and montane streams, has long larval development and overwinters. in contrast, tadpoles of P. bufoninum and R. s. papillosa use marshes and lower elevation ponds, and develop in three months. Tadpoles of Alsodes gargola tolerated experimental temperatures up to 32°c and those of the other two species lost the ability to move at temperatures near 38°c. Tadpoles of all species tolerated experimental exposure to 0°c for a limited period of time, but A. gargola had higher mortality rates when exposed to freezing than the other two species. These results are consistent with some traits of thermal ecology, exemplified by the higher thermal stability of the environments used by A. gargola. however, other factors such as physiological trade-offs may partially explain this pattern.
Remote lakes of northern Patagonia are ideal sites for examining climate- and non-climate-driven changes in aquatic ecosystems because there is little evidence of human influence and there is no detailed information on recent environmental trends in the region (i.e. the last 200 years). Subfossil chironomids (Diptera: Chironomidae) are useful paleoindicators due to their specific response to numerous environmental factors. Here, we analyze the chironomid subfossil assemblages from two remote lakes located in different environmental settings in Nahuel Huapi National Park of northern Patagonia, Argentina. Chironomids combined with sedimentary pigments (chlorophyll derivatives and total carotenoids) and organic matter provided information on the environmental history of the lakes for the last ca. 200 years. The 210Pb chronology and tephra layers are used to establish the chronology of changes in the chironomid assemblages associated to different environmental factors that impacted the area during the period covered by the study. The deposition of volcanic ash affected the abundance and composition of chironomid assemblage throughout the record of both lakes. However, changing climate conditions and human activities are also responsible for chironomid changes in the last 50 years.
Invasive alien species management in Patagonia, Argentina: Prioritization, achievements and science-policy integration challenges identified by the National Parks Administration: Invasive alien species are a threat to biodiversity. Management options encompass prevention, early detection, eradication, control, exclusion and even "no action." More technical information is needed to achieve complex management actions successfully. In addition, managers and researchers address the problem with different approaches. Managers seek to prioritize management actions, and for researchers, these species are an opportunity to study basic and/or theoretical aspects, but not always applied to management. However, the management strategies offer a unique opportunity for both groups to work together seeking mutual benefits. Currently, management decisions are often based on experiences or information from other countries, which is not always useful for local problems. We present several management experiences in the Argentine National Parks Administration to show achievements, difficulties and challenges usually faced by managers. We found that: a) it is important, when resources are scarce, to generate effective prioritization tools and networks; b) it is also vital to involve the community in the management actions; c) on the other hand, research directly applied to pilot eradication is required; and d) also, a careful planning, and continuity and monitoring of management actions and environmental results based on different types of first class technical information, are key aspects for successful management. Finally, managers and researchers must ensure that the results of applied research are known and understood by decision makers and the general public, to secure management support.
Almost 5 % of the lansdscape of Patagonia is occupied by wetlands. In the extra-andean region and the patagonian desert, wetlands are essential for sustaining biodiversity and wildlife. Besides, North patagonian wetlands present complex aquatic communities and provide habitat for threatened species of fishes and amphibians. These ecosystems have complex dynamics mostly driven by climatic fluctuations which make them vulnerable to the effect of climate change. Nowadays, the main impact on patagonian wetland is due to land use, species introduction, and the interaction of these disturbances with climate change. In this paper we summarize geographic, geomorphological and climatic information of several wetlands located in North Patagonia (Argentina). Besides, we present information on aquatic vegetation, fish and amphibian fauna distributions and endemisms with the aim of emphasizing the importance of wetlands to sustain regional biodiversity. Finally, we highlight the processes impacting wetlands at present time and point out the importance of obtaining basic information for management and conservation strategies.
RESUMEN Sobre la base de una evaluación del estado de conservación de la herpetofauna de Argentina, publicada recientemente, se analizan los factores determinantes del estatus asignado, con énfasis en las especies de las categorías que indican una mayor amenaza. De los 484 taxa evaluados el 23 % tiene problemas de conservación. Una proporción importante de estas especies tiene áreas de distribución restringidas, especialización en el uso del hábitat, está poco protegida y sufre acciones extractivas. Se analizan los principales factores de amenaza sobre los herpetozoos, encontrándose que la mayoría está afectada por la alteración del hábitat. Los reptiles sufren el comercio más intensamente que los anfibios. Se comparan los resultados de la nueva evaluación con la previa. El número de taxa de anfibios categorizados se incrementó un 42 % y el de reptiles un 58 %. Aparece la categoría Insuficientemente Conocida, que comprende el 33 % de la herpetofauna. PALABRAS CLAVES: estado de conservación, amenazas, anfibios, reptiles, Argentina. ABSTRACT Based on the new evaluation of the conservation status of Argentinian herpetofauna, recently published, the factors determining the assigned status are analyzed, with emphasis on the threatened species. Of the 484 taxa evaluated, 23 % has conservation problems. An important proportion of these species have restricted distribution areas, are habitat specialists, have poor protection and are subject to extractive actions. The main factors of threat to the herpetozoos are analyzed. The majority of them is affected by the alteration of the habitat. Reptiles undergo the trade more intensely than amphibians. The results of the new evaluation and the previous one are compared. The number of taxa of categorized amphibians was increased by 42 % and that of reptiles by 58 %. The newly created category, Insuffi-ciently known, includes 33 % of the herpetofauna.
Las especies exóticas invasoras amenazan la biodiversidad. Existen diferentes opciones para su manejo: prevención, detección temprana, erradicación, control, exclusión e incluso la "no acción". A mayor complejidad de manejo, más información se requiere para ejecutarlo exitosamente. Además, gestores e investigadores abordan la problemática con enfoques e intereses diferentes. Mientras los primeros priorizan acciones de manejo, los segundos encuentran una oportunidad para estudiar aspectos básicos y/o teóricos, no siempre aplicados al manejo. La gestión de estas especies ofrece una ocasión única para que ambos grupos trabajen juntos en busca de beneficios mutuos. Actualmente, las decisiones de manejo suelen basarse en experiencias o información de otros países, no siempre adaptables a la problemática local. En este trabajo presentamos varias experiencias de manejo en la Administración de Parques Nacionales para exponer logros, dificultades y desafíos a los que usualmente se enfrenta la gestión institucional. Encontramos que: a) ante recursos escasos es importante generar herramientas de priorización efectivas y redes de trabajo; b) es imprescindible involucrar a la comunidad en las acciones de manejo; c) se requieren investigaciones aplicadas al manejo específico; y d) es necesario una detallada planificación previa y un monitoreo de las acciones ejecutadas y de sus resultados, basados en información técnica de primer nivel, ya que son aspectos claves para un manejo exitoso. Finalmente, gestores e investigadores deben cerciorarse que los resultados de estas investigaciones aplicadas sean conocidos y comprendidos por los tomadores de decisiones y la opinión pública, para asegurar el apoyo a la gestión. [Palabras clave: áreas protegidas, conservación, control, erradicación, gestión, invasiones biológicas, manejo, Patagonia, planificación]
The Patagonia frog Atelognathus patagonicus (Anura, Ceratophryidae) is endemic to north-western Patagonia where it inhabits permanent and temporary water bodies in a system of endorheic ponds on the basaltic plateau in and around Laguna Blanca National Park, northwestern Patagonia, Argentina. This Endangered species is emblematic of the decline and extinction of amphibian populations as a result of the introduction of fish to Laguna Blanca. Therefore, the aims of this study were to determine the patterns of larval development in ponds with different hydro periods and to evaluate the occurrence of different developmental strategies and their implications for conservation management. In permanent ponds, A. patagonicus tadpoles showed a double strategy, with the presence of both seasonal (short larval period; metamorphs in the same growing season) and overwintering tadpoles (undergoing metamorphosis the following spring). In temporary ponds, desiccation seems to exert great pressure, with accelerated larval development, resulting in short larval periods. Atelognathus patagonicus showed plasticity in the length of larval development, adjusting to the different hydroperiods observed in these wetlands. As a result of this dual strategy, overwintering tadpoles in permanent ponds are larger than seasonal tadpoles. This notable plasticity in developmental strategy enables this species to colonize widely varying environments. These results highlight the importance of preserving a variety of wetlands, including both temporary and permanent ponds, to allow this species to continue to breed and develop in the face of current and potential anthropogenic disturbance, in particular that caused by the activity of local native pastoralists.
Based on the new evaluation of the conservation status of Argentinian herpetofauna, recently published, the factors determining the assigned status are analyzed, with emphasis on the threatened species. Of the 484 taxa evaluated, 23 % has conservation problems. An important proportion of these species have restricted distribution areas, are habitat specialists, have poor protection and are subject to extractive actions. The main factors of threat to the herpetozoos are analyzed. The majority of them is affected by the alteration of the habitat. Reptiles undergo the trade more intensely than amphibians. The results of the new evaluation and the previous one are compared. The number of taxa of categorized amphibians was increased by 42 % and that of reptiles by 58 %. The newly created category, Insufficiently known, includes 33 % of the herpetofauna
Almost 5 % of the lansdscape of Patagonia is occupied by wetlands. In the extra-andean region and the patagonian desert, wetlands are essential for sustaining biodiversity and wildlife. Besides, North patagonian wetlands present complex aquatic communities and provide habitat for threatened species of fishes and amphibians. These ecosystems have complex dynamics mostly driven by climatic fluctuations which make them vulnerable to the effect of climate change. Nowadays, the main impact on patagonian wetland is due to land use, species introduction, and the interaction of these disturbances with climate change. In this paper we summarize geographic, geomorphological and climatic information of several wetlands located in North Patagonia (Argentina). Besides, we present information on aquatic vegetation, fish and amphibian fauna distributions and endemisms with the aim of emphasizing the importance of wetlands to sustain regional biodiversity. Finally, we highlight the processes impacting wetlands at present time and point out the importance of obtaining basic information for management and conservation strategies.
Atelognathus patagonicus is an endangered leptodactylid frog endemic to a small region in and around Laguna Blanca National Park in northern Patagonia, Argentina. All of the lakes and small ponds of the region (except Laguna Blanca itself) contain A. patagonicus and in all but one of these lakes the species shows clinical signs of a previously undiagnosed disease, the characteristics of which suggested a ranavirus. We collected symptomatic and asymptomatic A. patagonicus frogs and tadpoles from 4 small lakes and analyzed tissues for ranavirus and the chytrid fungus Batrachochytrium dendrobatidis using PCR amplification of pathogen DNA. Of the 32 specimens tested, 25 were positive for ranavirus major capsid protein (MCP). Sequence alignments of the ranavirus MCP from these specimens showed 100% similarity with published FV3 and FV3-like viruses from anurans, 98 to 99 % similarity with Bohle iridovirus, and 95 % similarity with Ambystoma tigrinum virus (ATV) and Regina ranavirus (RRV). A search of the NCBI Blast nucleotide database using the 500 base pair MCP sequence obtained from these samples did not suggest any homology to any other pathogen. In addition, 1 sample (3 pooled individuals) from 1 lake tested positive for B. dendrobatidis. The clinical signs observed primarily in late-stage tadpoles and recent metamorphs, which have reoccurred each year since at least 2001, are consistent with ranaviral disease, but until histopathology of diseased individuals is carried out, chytridiomycosis or other diseases cannot be ruled out.
Extinctions are normal biological phenomena. Both mass extinctions in geological time and local extinctions in ecological time are well documented, but rates of extinction have increased in recent years—especially in vertebrates, including amphibians—as illustrated by recent reports of their population declines and range reductions. We suggest that long-term population data are necessary for rigorously evaluating the significance of the amphibian declines. Due to the physiological constraints, relatively low mobility, and site fidelity of amphibians, we suggest that many amphibian populations may be unable to recolonize areas after local extinction.
Las extinciones son un fenómeno biológico normal. Extinciones en masa en una escala temporal geológica y extinciones locales en una escala temporal ecológica, están bien documentadas, pero en años recientes las tasas de exinción han incrementado, especialmente en vertebrados, incluyendo a los anfibios tal como ha sido ejemplificado en reportes recientes sobre la declinación de su población y la reducción de su área de distribución. Nosotros sugerimos que datos poblacionales a largo plozo son necesarios para evaluar rigurosamente la significancia de la declinación en anfibios. Nosotros sugerimos que muchas de las poblaciones de anfibios son incapaces de recolonizar áreas después de extinciones locales debido a las restricciones fisiológicas, la relativamente baja movilidad y la filopatría de los anfibios.
Solar ultraviolet (UV) radiation poses a threat to most living organisms. Aquatic organisms have evolved three basic mechanisms to cope with harmful levels of radiation. Two mechanisms, avoidance (e.g. vertical migration) and photoprotection (e.g. production of photoprotective compounds that act as filters, antioxidants, etc.), serve to minimize the dose of UV radiation that reaches the organism's vital structures (DNA, membranes, etc.). The third mechanism, repair (e.g. dark repair mechanisms, such as nucleotide excision repair; or photoreactivation mechanisms, such as photoenzymatic repair), serves to repair the damage following UV exposure, Here, we compare the vulnerability to UV-B radiation of three copepod species (Boeckella brevicaudata, Boeckella gibbosa, and Boeckella gracilipes) that occur in lakes that differ in UV-B penetration and depth. Our aim was to gain insight into the significance of each of the three mechanisms in different UV-B environments. Results from a 3-day 'in situ' incubation in ultra-oligotrophic Lake Toncek showed that B.gracilipes is highly vulnerable to UVB and UV-A radiation. In contrast, virtually no mortality was observed in B.gibbosa and B.brevicaudata during the same period. In order to discriminate the contribution of photoprotection and photoreactivation, the three species were subsequently exposed in the laboratory to an artificial source of UV-B radiation, both in the presence and absence of visible radiation (recovery radiation). The photoprotection potential (i.e. resistance to UV-B in the absence of recovery radiation) of B.gracilipes and B.gibbosa was lower than that of B.brevicaudata. On the other hand, photoreactivation (higher resistance to UV-B in the presence of recovery radiation) was observed in B.brevicaudata and B.gibbosa, but not in B.gracilipes. To cope with damaging UV-B levels in nature, B.gracilipes depends exclusively on the attenuation by the external media (i.e. avoidance). Although B.gibbosa tends to avoid the surface waters of lakes, it also occurs in shallow transparent pools. Most likely its ability to survive in these shallow, high UV environments is due to its photoreactivation potential. Finally, despite its occurrence in highly turbid lakes, B.brevicaudata seems extremely well suited to cope with UV-B radiation thanks to a combination of photoreactivation and photoprotection.
En el presente trabajo se evalúa el estado de conservación, a nivel nacional y local, de las aves del Parque Nacional Nahuel Huapi, mediante un índice compuesto por 12 variables relevantes para la sobrevivencia de las especies. Este índice fue calculado para las 113 especies de aves autóctonas residentes en el área de estudio, lo que permitió realizar un listado de estas especies priorizadas según su necesidad o estado de conservación en el país. Con el agregado de una variable referida a una condición particular de las especies en el Parque, se obtuvo otro listado que refleja la necesidad o estado de conservación de las aves dentro del mismo. Las variables del índice que más contribuyeron a aumentar su valor (y en consecuencia el valor de conservación de las especies), fueron las referidas a distribución, plasticidad en el uso del espacio vertical, potencial reproductivo y amplitud trófica. La priorización obtenida fue comparada con calificaciones del estado de conservación de las mismas especies realizadas por otros autores, detectándose diferencias y similitudes. Se concluye que la metodología empleada responde cumpliendo con los objetivos trazados y que es una herramienta útil para el manejo y la conservación de la fauna silvestre.
1. This review considers the periodic cycles of species dominance in a wide selection of temperate lakes. By ascribing individual species to assemblages, a high incidence of similarity among periodic cycles is demonstrated. Reference to lakes at high and low latitudes, as well as to rivers, shows conformity to parts of the same broad patterns.
2. The role of population dynamics in shaping community structure is emphasized. Two types of change are recognized: autogenic, undirectional subsequences (successions), regulated by specific responses to critically changing resource-ratio gradients; and allogenic changes, regulated by variability in the physical environment.
3. Analysis of the responses of representative species to allogenic change permits further grouping of the assemblages. These groupings coincide with clear morphological distinctions among the same phytoplankton species according to their unit sizes and surface area/volume ratios.
4. It is argued that these properties condition the physiological responses of algae to seasonal variations in temperature, mixing and exposure to the underwater light field. The responses are compounded by relative resistances to loss processes (sinking, grazing), by short-term photosynthetic adaptation and vertical migratory behaviour.
5. Graphical summaries are presented that relate the morphologically-, physiologically- and behaviourally-mediated responses to a hierarchy of physical, chemical and biotic environmental variables. Phytoplankton periodicity is the outcome of these interactions.
Ley 2056, Arts. 8, 9 and 12
- Rí Provincia
- Negro
Provincia de Rí Negro (1993) Ley 2056, Arts. 8, 9 and 12. Disposició n Subdirecció n de Fauna 05/93: Especies protegidas de la Fauna Silvestre Provincial.
Amphibian Species of the World: Additions and Corrections, Special Publication No. 21, i–iii, pp. 372. The University of Kansas, Museum of Natural History
- W E Duellman
Duellman, W.E. (1993) Amphibian Species of the World: Additions and Corrections, Special Publication No. 21, i–iii, pp. 372. The University of Kansas, Museum of Natural History, Lawrence, KS, USA.
Biogeografí de Amé Latina, Segunda edició n, Serie de Biologí, Monografí No. 13, vi+ pp. 117. Secretarí General de la OEA
- A L Cabrera
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Cabrera, A.L. & Willink, A. (1980) Biogeografí de Amé Latina, Segunda edició n, Serie de Biologí, Monografí No. 13, vi+ pp. 117. Secretarí General de la OEA, Programa Regional de Desarrollo Cientifí y Tecnoló gico, Washing-ton, D.C.
Amphibian Species of the World. A Taxonomic and Geographical Reference Allen Press Inc. and The Association of Systematics Collections Measuring and Monitoring Biological Diversity
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- L A C Hayek
- M S Foster
Frost, D.R. (1985) Amphibian Species of the World. A Taxonomic and Geographical Reference, pp. 732. Allen Press Inc. and The Association of Systematics Collections, Lawrence, KS, USA. Heyer, W.R., Donnelly, M.A., McDiarmid, R.W., Hayek, L.A.C. & Foster, M.S. (1994) Measuring and Monitoring Biological Diversity. Standard Methods for Amphibians, pp. 364. Smith-sonian Institution Press, Washington and London. IUCN (1996) 1996 IUCN Red List of Threatened Animals. IUCN — The World Conservation Union, Gland, Switzerland.
Cartas de precipitació de la zona oeste de las provincials de Rí Negro y Neuqué. Primera Contribució n, pp. 28 + figs The tadpole of Atelognathus nitoi (Leptodactylidae: Telmatobiinae)
- V R Barros
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- O N G Pizzio
Barros, V.R., Cordon, V.H., Moyano, C.L., Mé, R.J., For-quera, J.C. & Pizzio, O. (1983) Cartas de precipitació de la zona oeste de las provincials de Rí Negro y Neuqué. Primera Contribució n, pp. 28 + figs. Universidad Nacional del Comahue and Centro Nacional Patagó nico-CONICET, Cinco Saltos, Rí Negro. Basso, N.G. & U ´ beda, C.A. (1997) The tadpole of Atelognathus nitoi (Leptodactylidae: Telmatobiinae). Alytes, 15(3), 121 – 126.
Declining amphibian populations — a global phenomenon? Findings and
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- H J Morowitz
Wake, D.B. & Morowitz, H.J. (1991) Declining amphibian populations — a global phenomenon? Findings and
Nota sull'uso dei volumi algali per la stima della biomassa
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Trevisan, R. (1979) Nota sull'uso dei volumi algali per la stima
della biomassa. Rivista di Idrobiologia, 17(3), 345-357.
Fitoplancton de lagos Andino-Patagónicos
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Diaz, M. (1994) Fitoplancton de lagos Andino-Patagó. Su relació con factores abió, pp. 178. PhD thesis, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires.
Una nueva especie de Telmatobius (Anura, Leptodactylidae) procedente del dominio austral cordillerano argentino
- A Barrio
Barrio, A. (1973) Una nueva especie de Telmatobius (Anura,
Leptodactylidae) procedente del dominio austral cordillerano argentino. Physis (Buenos Aires) Secc. C, 32(84), 207-213.
The relations between zooplankton and phytoplankton in lake Erken
- Nauwerk
Cartas de precipitation de la zona oeste de las provincials de Rio Negro y Neuquhi. Primera Contribution, pp. 28 + figs
- V R Barros
- V H Cordon
- C L Moyano
- R J Mendez
- J C Forquera
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Barros, V.R., Cordon, V.H., Moyano, C.L., Mendez, R.J., Forquera, J.C. & Pizzio, O. (1983) Cartas de precipitation de la
zona oeste de las provincials de Rio Negro y Neuquhi. Primera
Contribution, pp. 28 + figs. Universidad Nacional del
Comahue and Centro Nacional Patagonico-CONICET,
Cinco Saltos, Rio Negro.
Serie de Biologia, Monografia No. 13, vi + pp. 117. Secretaria General de la OEA
- A L Cabrera
- A Willink
Cabrera, A.L. & Willink, A. (1980) Biogeografia de America
Latina, Segunda edition, Serie de Biologia, Monografia No.
13, vi + pp. 117. Secretaria General de la OEA, Programa
Regional de Desarrollo Cientifico y Tecnologico, Washington, D.C.
Fitoplancton de lagos Andino-Patagdnicos. Su relation con factores abioticos
- M Diaz
Diaz, M. (1994) Fitoplancton de lagos Andino-Patagdnicos. Su
relation con factores abioticos, pp. 178. PhD thesis, Facultad
de Ciencias Exactas y Naturales, Universidad de Buenos
Aires.
IUCN Red List of Threatened Animals
- Iucn
IUCN (1996) 1996 IUCN Red List of Threatened Animals.
IUCN-The World Conservation Union, Gland,
Switzerland.
Ley 2056, Arts. 8, 9 and 12. Disposition Subdireccion de Fauna 05/93: Especies protegidas de la Fauna Silvestre Provincial
- Provincia De
- Rio Negro
Provincia de Rio Negro (1993) Ley 2056, Arts. 8, 9 and 12.
Disposition Subdireccion de Fauna 05/93: Especies protegidas
de la Fauna Silvestre Provincial.
Declining amphibian populations-a global phenomenon? Findings and recommendations
- D B Wake
- H J Morowitz
Wake, D.B. & Morowitz, H.J. (1991) Declining amphibian
populations-a global phenomenon? Findings and recommendations. Workshop sponsored by the Board on Biology, National Research Council of the USA. Alytes, 9(2),
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