Examinando por Autor "Quirici, Verónica"
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Ítem Age and terminal reproductive attempt influence laying date in the thorn-tailed rayadito(Blackwell Publishing Ltd, 2019-10) Quirici, Verónica; Hammers, Martijn; Botero-Delgadillo, Esteban; Cuevas, Elfego; Espíndola-Hernández, Pamela; Vásquez, Rodrigo A.Age-specific variation in reproductive effort can affect population dynamics, and is a key component of the evolution of reproductive tactics. Late-life declines are a typical feature of variation in reproduction. However, the cause of these declines, and thus their implications for the evolution of life-history tactics, may differ. Some prior studies have shown late-life reproductive declines to be tied to chronological age, whereas other studies have found declines associated with terminal reproduction irrespective of chronological age. We investigated the extent to which declines in late life reproduction are related to chronological age, terminal reproductive attempt or a combination of both in the thorn-tailed rayadito Aphrastura spinicauda, a small passerine bird that inhabits the temperate forest of South America. To this end we used long-term data (10 years) obtained on reproductive success (laying date, clutch size and nestling weight) of females in a Chilean population. Neither chronological age nor terminal reproductive attempt explained variation in clutch size or nestling weight, however we observed that during the terminal reproductive attempt older females tended to lay later in the breeding season and younger females laid early in the breeding season, but this was not the case when the reproductive attempt was not the last. These results suggests that both age-dependent and age-independent effects influence reproductive output and therefore that the combined effects of age and physiological condition may be more relevant than previously thought. © 2019 Nordic Society Oikos. Published by John Wiley & Sons Ltd.Ítem Baseline Corticosterone, Stress Responses, and Leukocyte Profiles in Chicks of Precocial Birds in Rural and Urban Environments(Multidisciplinary Digital Publishing Institute (MDPI), 2023-11) Quirici, Verónica; Valeris-Chacín, Carlos E.; Parada, Pablo; Cuevas, Elfego; Wingfield, John C.The urban environment produces complex relationship among urban stressors that could change the levels of the steroid hormone, glucocorticoid (GCs). Studies that have evaluated baseline corticosterone (Cort) levels (the main GC in birds) and stress responses during development in urban and rural environments have obtained contrasting results. This ambiguity could partially be because the studies were carried out in altricial species, where parental care and sibling competition can affect Cort levels. Therefore, in this study, we compared levels of circulating baseline levels of CORT (blood sample obtained within 3 min of capture) and stress responses (blood sample obtained 30 min after capture) and the H/L ratio (an alternative method to measure stress) in chicks of a precocial bird, southern lapwings (Vanellus chilensis), from one rural (6 chicks), one urban low-polluted (13 chicks), and one urban high-polluted (10 chicks) site of Metropolitan Region of Santiago de Chile. We observed higher baseline Cort (2.41 ± 1.78 ng/mL) in the urban high-polluted site, a higher H/L ratio (0.51 ± 0.20) in the urban low-polluted site, and similar stress response across the three sites. We propose that the difference in stress physiology we observed within Santiago de Chile is because the two zones are at extremes in terms of stressors (noise, light, chemical, and human presence). It is unusual to find a precocious bird that lives in both urban and rural areas; therefore, the results of this study will advance our knowledge of the effect of the urban environment during the development of wildlife, which is relevant in terms of management and conservation. © 2023 by the authors.Ítem Effect of drought disturbance in a sclerophyll forest on the micromammal community in the Río Clarillo National Park, Metropolitan Region, Chile(0716078X, 0025-12) Fletcher, Susan; Sarmiento, Carlos; Stotz, Gisela C.; Quirici, VerónicaBackground: Micromammals play an important role in mediterranean ecosystems. The “megadrought” in the sclerophyll forest has caused a “browning” that implies, among other things, the reduction of canopy cover. The effects of forest browning on the taxonomic and functional diversity of micromammals were evaluated. Methods: Forests with high and low disturbance degree were characterized based on the level of browning and canopy cover. To study the community of micromammals in these forests, the Capture-Mark-Recapture method was used with Sherman traps. Community indices such as Shannon–Wiener and Pielou were calculated. The Coefficient of Variation was used to study functional diversity for each trait separately. Multivariate measures FRic, FEve and FDiv were used to determine multidimensional diversity. Results: We observed differences in species composition and in richness, diversity, and cover variables between forest types. However, micromammal communities were similar in taxonomic and functional diversity in highly and slightly disturbed forests. Discussion: The micromammal community appears to show some resistance to forest changes due to disturbance, which could be related to their generalist diet and high dispersal capacity. The presence of the genus Rattus could entail a decrease in native rodent diversity and could have a greater effect than the disturbance of the forest due to drought. These results are an invitation to conduct long-term studies to better understand the potential vulnerability of the different micromammal species to disturbed sclerophyll forests affected by drought. © The Author(s) 2025.Ítem Effects of traffic noise exposure on corticosterone, glutathione and tonic immobility in chicks of a precocial bird(Conservation Physiology, 2019-01-01) Flores, Romina; Mario, Penna; Wingfield, John C.; Cuevas, Elfegod; Vásquez, Rodrigo A.; Quirici, Verónica; Conservation PhysiologyRepeated exposure to traffic noise may be perceived as a succession of stressors, and therefore, noisy urban environments could lead to a state of chronic stress. In developing animals, glucocorticoids can have organizational effects on the hypothalamic-pituitary-adrenal axis in addition to the classic activation effects, so evaluating the effect of traffic noise during development is urgently needed. To our knowledge, to date six studies have investigated the effects of traffic noise on baseline corticosterone (CORT) and/or the stress response in birds during development; however, these studies were performed in nestling (altricial species), where confounding factors (e.g. communication between nestlings and parents) could mask the real impact of traffic noise on stress. In this study, we evaluated the effect of traffic noise (traffic noise group vs. rural noise group) on baseline levels of CORT and stress responses in chicks of a precocial bird species, the Japanese quail (Coturnix japonica). Because CORT can also decrease glutathione (GSH) levels (antioxidant and neurotransmitter/modulator), secondly by means of path analysis we investigated whether the strength of the association between CORT levels, GSH levels and tonic immobility (TI) varied in relation to treatment. We observed (i) similar baseline levels of CORT in both groups, (ii) a trend toward higher stress response in the traffic noise group (P = 0.08), (iii) similar TI duration in both groups, (iv) higher GSH levels in the traffic noise group and (v) differences in the strength and sign of the associations in relation to the treatment (traffic vs. rural). We conclude that the acoustic environment perceived during development has implications for physiology and behaviour; as more research is done on this topic, the need for sustainable urban planning will become clearer. © 2019 The Author(s) 2019. Published by Oxford University Press and the Society for Experimental Biology.Ítem Extrapair paternity in two populations of the socially monogamous thorn-tailed rayadito aphrastura spinicauda (Passeriformes: Furnariidae)(John Wiley and Sons Ltd, 2020-11) Botero-Delgadillo, Esteban; Quirici, Verónica; Ippi, Silvina; Kempenaers, Bart; Vásquez, Rodrigo A.Studies on extrapair paternity (EPP) are key to understanding the ecological and evolutionary drivers of variation in avian mating strategies, but information is cur-rently lacking for most tropical and subtropical taxa. We describe the occurrence of EPP in two populations of a South American socially monogamous bird, the Thorn-tailed Rayadito, based on data from 266 broods and 895 offspring that were sam-pled during six breeding seasons in north-central and southern Chile. In the northern population, 21% of the broods contained at least one extrapair young and 14% of all offspring were sired by an extrapair male, while in the southern population, we detected extrapair offspring (EPO) in 14% of the broods, and 6% of all offspring were EPO. Variation in the frequency of EPP could stem from population differences in the duration of the breeding season or the density of breeding individuals. Other factors such as differences in breeding synchrony and variation in food availability need to be evaluated. More reports on EPP rates are necessary to determine the patterns of taxonomic and geographic variation in mating strategies in Neotropical birds, and to better understand the differences in ecological dynamics between northern and southern hemisphere populations.Ítem Latitudinal gradients of haemosporidian parasites: Prevalence, diversity and drivers of infection in the Thorn-tailed Rayadito (Aphrastura spinicauda)(Australian Society for Parasitology, 2020-04) Cuevas, Elfego; A. Vianna, Juliana; Botero-Delgadillo, Esteban; Doussangg, Daniela; González-Acuña, Daniel; Barroso, Omar; Rozzi, Ricardo; A. Vásquez, Rodrigo; Quirici, VerónicaLatitudinal gradients are well-suited systems that may be helpful explaining distribution of haemosporidian parasites and host susceptibility. We studied the prevalence, diversity and drivers of haemosporidian parasites (Leucocytozoon, Plasmodium and Haemoproteus) along a latitudinal gradient (30°–56° S), that encompass the total distribution (~3,000 km) of the Thorn-tailed Rayadito (Aphrastura spinicauda) in the South American temperate forests from Chile. We analyzed 516 individuals from 18 localities between 2010 and 2017 and observed an overall prevalence of 28.3% for haemosporidian parasites. Leucocytozoon was the most prevalent parasite (25.8%). We recorded 19 distinct lineages (13 for Leucocytozoon, five for Plasmodium, and one for Haemoproteus). Differences in haemosporidian prevalence and diversity by genus and type of habitat were observed in the latitudinal gradient. Further, we support the existence of a latitudinal associate distribution of Leucocytozoids in South America, where prevalence and diversity increase toward higher latitudes. Distribution of Leucocytozoon was associated with sub-antarctic habitat (higher latitude) and explained by cold temperature and high precipitation. On the other hand, we lacked to find a latitudinal associate pattern for Plasmodium and Haemoproteus, however low prevalence and high diversity were recorded in areas considered as a hotspot of biodiversity in Central Chile. Our findings confirmed the importance of habitat and climatic variables explaining prevalence, diversity and distribution of haemosporidian parasites in a huge latitudinal gradient, belonging the distribution of the Thorn-tailed Rayadito in the world's southernmost forests ecosystems. © 2019 The AuthorsÍtem The avifauna of bosque Fray Jorge National Park and Chile's Norte Chico(Academic Press, 2016-03) Kelt, Douglas A.; Cofré, Hernán; Cornelius, Cintia; Engilis, Andrew; Gutiérrez, Julio R.; Marquet, Pablo A.; Medel, Rodrigo; Meserve, Peter L.; Quirici, Verónica; Samaniego, Horacio; Vásquez, Rodrigo A.The avifauna of Chile is relatively depauperate, comprising 469 extant species, of which 213 are terrestrial. However, the Coquimbo Region presents a broad ecological transition from the hyperarid Atacama Desert to the north, and the more mesic Chilean Mediterranean region of central Chile, resulting in relatively high species diversity. Approximately 130 species are found here, 8 of which are endemic to Chile although not to this region. Bosque Fray Jorge National Park is a 9959 ha Biosphere Reserve dominated by matorral habitat and hosting up to 123 bird species. Through avian surveys and banding over nearly a decade we have documented 63 terrestrial species and discerned predictable seasonal and interannual structure to avian assemblages, at least through an extended dry period. Recent studies in the matorral habitats of the park indicate seasonal patterns that fall into 4 patterns: year-round resi dents, winter visitors, summer breeders, and transients. Short-term banding studies demonstrate co occurring wintering and breeding cohorts among species of Sierra-finches (Phrygilus) in the park; such assemblages and dynamics are reminiscent of North American Mediterranean avian assemblages and pose interesting ecological comparisons. In this period of surveys there appears to have been a gradual transition of the avifauna that may be a response to anthropogenic influence and/or climate change. Research on the foraging behavior of 2 insectivorous species indicate that one of these is convergent on better-known North American taxa while the other clearly is not; these efforts suggest useful avenues for further comparative research. A remarkable coevolutionary association between the Chilean Mockingbird (Mimus thenca) and endoparasitic mistletoes (Tristerix) provides insight into po tential convergent ecologies in desert regions with different evolutionary histories. Less than 1% of the park comprises temperate forest remnants that subsist due to extensive water input from fog. Research in these remnants has emphasized the role of habitat fragmentation on avian assemblage composition and on reproductive ecology by forest-dependent species. The avifauna here comprises a subset of that found in intact Valdivian rainforest to the south, and forest remnant size alone explains over 90% of the variation in species numbers. One species has been particularly well studied; the Thorn-tailed Rayadito (Aphrastura spinicauda) is more abundant and has higher nestling survival in larger fragments. We summarize other work on stress responses and variation in song structure in this species. Finally, the role of birds in tree recruitment here has important implications in the face of a recent history of reduction in sizes of forest remnants; numerous birds consume the fruit of the dominant tree, olivillo(Aextoxicon punctatum), but they fail to promote successful recruitment because they defecate viable seeds in locations that provide poor survival of seedlings. Ornithological research in Chile is undergoing a modest renaissance, and while dryland avifaunas are characterized more by what is not known and has yet to be studied than by actual ecological under standing, they provide a baseline for many exciting studies ranging from natural history to the role of migration to comparative dynamics of independent lineages in North and South America. © 2015 Elsevier Ltd. All rights reserved