PRIMERA DESCRIPCIÓN SOBRE LA ANIDACIÓN DEL DACNIS ANDINO NORTEÑO (XENODACNIS PETERSI) EN ECUADOR

Resumen ∙ Se presenta nueva información sobre la biología reproductiva del Dacnis Andino Norteño (Xenodacnis petersi). En Ecuador esta especie se encuentra en los altos Andes, principalmente en el Parque Nacional Cajas, donde encontramos cinco nidos entre septiembre de 2017 y noviembre de 2018. Los nidos en forma de taza estaban construidos en cuatro plantas diferentes, con la pubescencia de las flores de Puya sp., musgo, paja y ramas secas como materiales principales. El tamaño de la puesta fue de uno a dos huevos y se colocaron en días consecutivos. La hembra estuvo a cargo de la incubación, mientras que ambos sexos se hicieron cargo de las crías. La incubación duró entre 17 y 20 días, y los polluelos permanecieron en el nido durante 16 a 18 días. Abstract ∙ First nesting description of the Streaked Dacnis (Xenodacnis petersi) in Ecuador Here we report new information on the reproductive biology of the Streaked Dacnis (Xenodacnis petersi). In Ecuador, this species is found in the high Andes, mainly in Cajas National Park, where we found five nests between September 2017 and November 2018. The cup-shaped nests were built on four different plants, with the pubescence of flowers of Puya sp., moss, straw and dry branches as the main materials. Clutch size was one or two eggs and these were laid on consecutive days. The female was in charge of the incubation, while both sexes took care of the chicks. Incubation lasted between 17 to 20 days, and the chicks remained in the nest for 16 to 18 days

Model-based analysis of the potential of macroinvertebrates as indicators for microbial pathogens in rivers

The quality of water prior to its use for drinking, farming or recreational purposes must comply with several physicochemical and microbiological standards to safeguard society and the environment. In order to satisfy these standards, expensive analyses and highly trained personnel in laboratories are required. Whereas macroinvertebrates have been used as ecological indicators to review the health of aquatic ecosystems. In this research, the relationship between microbial pathogens and macrobenthic invertebrate taxa was examined in the Machangara River located in the southern Andes of Ecuador, in which 33 sites, according to their land use, were chosen to collect physicochemical, microbiological and biological parameters. Decision tree models (DTMs) were used to generate rules that link the presence and abundance of some benthic families to microbial pathogen standards. The aforementioned DTMs provide an indirect, approximate, and quick way of checking the fulfillment of Ecuadorian regulations for water use related to microbial pathogens. The models built and optimized with the WEKA package, were evaluated based on both statistical and ecological criteria to make them as clear and simple as possible. As a result, two different and reliable models were obtained, which could be used as proxy indicators in a preliminary assessment of pollution of microbial pathogens in rivers. The DTMs can be easily applied by staff with minimal training in the identification of the sensitive taxa selected by the models. The presence of selected macroinvertebrate taxa in conjunction with the decision trees can be used as a screening tool to evaluate sites that require additional follow up analyses to confirm whether microbial water quality standards are met

Ciencia ciudadana e interacciones entre aves nectarívoras y plantas de páramo en el Parque Nacional Cajas

We analyzed the interactions between nectarivores birds and paramo plants at Cajas National Park, Azuay, Ecuador, using citizen science information from the eBird platform. Our analysis was based on clues extracted from photographs and videos available on this platform. A total of 24 interactions were identified between eight nectarivores birds and 14 plant genera. At the network level, we calculated connectance (C), and at the species level, we calculated degree (D), or the number of interactions of each species. We used the platform R to visualize the interactions network and calculate each index. We found that the endemic hummingbird Violet-throated Metaltail, Metallura baroni, and Blue-mantled Thornbill, Chalcostigma stanleyi, as well as genus Gynoxys, showed the majority of interactions, suggesting their importance for the ecosystems of Cajas National Park.En este estudio se analiza la red de interacciones entre aves nectarívoras y plantas de páramo en el Parque Nacional Cajas, Azuay, Ecuador, utilizando información de ciencia ciudadana de la plataforma eBird. La información para el análisis fue extraída de fotografías y videos disponibles en esta plataforma. En total se identificaron 24 interacciones entre ocho especies de aves y 14 géneros de plantas. A nivel de red se calculó el índice de conectancia (C), mientras que, a nivel de especie, se calculó el grado (D) o número de interacciones de cada especie. Se utilizó el software R para visualizar la red de interacción y calcular cada índice. Se encontró que el colibrí endémico Metalura Gorjivioleta, Metallura baroni, y el Picoespina Dorsizaul, Chalcostigma stanleyi, así como el género Gynoxys, mostraron una mayor cantidad de interacciones, sugiriendo su importancia en los ecosistemas del Parque Nacional Cajas

A methodology to model environmental preferences of EPT taxa in the Machangara river basin (Ecuador)

Rivers have been frequently assessed based on the presence of the Ephemeroptera— Plecoptera—Trichoptera (EPT) taxa in order to determine the water quality status and develop conservation programs. This research evaluates the abiotic preferences of three families of the EPT taxa Baetidae, Leptoceridae and Perlidae in the Machangara River Basin located in the southern Andes of Ecuador. With this objective, using generalized linear models (GLMs), we analyzed the relation between the probability of occurrence of these pollution-sensitive macroinvertebrates families and physicochemical water quality conditions. The explanatory variables of the constructed GLMs differed substantially among the taxa, as did the preference range of the common predictors. In total, eight variables had a substantial influence on the outcomes of the three models. For choosing the best predictors of each studied taxa and for evaluation of the accuracy of its models, the Akaike information criterion (AIC) was used. The results indicated that the GLMs can be applied to predict either the presence or the absence of the invertebrate taxa and moreover, to clarify the relation to the environmental conditions of the stream. In this manner, these modeling tools can help to determine key variables for river restoration and protection management.Rivers have been frequently assessed based on the presence of the Ephemeroptera— Plecoptera—Trichoptera (EPT) taxa in order to determine the water quality status and develop conservation programs. This research evaluates the abiotic preferences of three families of the EPT taxa Baetidae, Leptoceridae and Perlidae in the Machangara River Basin located in the southern Andes of Ecuador. With this objective, using generalized linear models (GLMs), we analyzed the relation between the probability of occurrence of these pollution-sensitive macroinvertebrates families and physicochemical water quality conditions. The explanatory variables of the constructed GLMs differed substantially among the taxa, as did the preference range of the common predictors. In total, eight variables had a substantial influence on the outcomes of the three models. For choosing the best predictors of each studied taxa and for evaluation of the accuracy of its models, the Akaike information criterion (AIC) was used. The results indicated that the GLMs can be applied to predict either the presence or the absence of the invertebrate taxa and moreover, to clarify the relation to the environmental conditions of the stream. In this manner, these modeling tools can help to determine key variables for river restoration and protection management