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Predation of Long-tailed Silky Flycatcher (Ptilogonys caudatus) by Ornate Hawk-Eagle (Spizaetus ornatus) in a cloud forest of Costa Rica
(2012-12) Acosta Chaves, Víctor; Granados Rodríguez, Federico; Araya Huertas, David
Predation of Long–tailed Silky Flycatcher (Ptilogonys caudatus) by Ornate Hawk–Eagle (Spizaetus ornatus) in a cloud forest of Costa Rica. This paper is the first record of a predation event made by an Hawk–Eagle (S.ornatus, Accipitridae) on a Long–tailed Silky Flycatcher (P. caudatus, Ptilogonatidae) in a cloud forest of Costa Rica, and this is the first prey item reported for this raptor in a middle elevation forest. Also this is the first predation event reported for the Ptilogonatidae family.
Shifts in the diversity of an amphibian community from a premontane forest of San Ramón, Costa Rica
(Universidad de Costa Rica, 2019-05-14) Acosta Chaves, Víctor; Madrigal Elizondo, Victor Hugo; Chaves, Gerardo; Morera Chacón, Brayan Heiner; García Rodríguez, Adrián; Bolaños Vives, Federico
Biological communities are experiencing rapid shifts of composition in Neotropical ecosystems due to several factors causing population declines. However, emerging evidence has provided insights on the adaptive potential of multiple species to respond to illnesses and environmental pressures. In Costa Rica, the decline of amphibian populations is a remarkable example of these changes. Here we provide evidence of variation in the amphibian richness of a premontane forest of San Ramón (Costa Rica) across a ~30 year period. We also quantified changes in the composition and abundance of the leaf-litter frog community occurring in the same premontane forest, by comparing diversity data with a difference of ~18 years. We evaluated the similarity of species richness from 1980s to 2010s based on several sources, and the dissimilarity of species diversity in the site comparing 28 standardized surveys from 1994-1995 and 2011-2012. We compared the relative abundance of some frogs that inhabit the leaf-litter layer between these same periods. Our results show that there is more similarity in amphibian richness between 1980s and 2010s (~ 52 %) than between 1980s and 1990s (~ 40 %). The richness of leaf-litter anurans was ~ 65 % similar between 1990s and 2010s. The diversity of leaf-litter anuran was clearly different between 1994-1995 and 2011-2012, and it was clustered among those periods. We determined that the amphibian community in this premontane forest drastically changed: many species have disappeared, or gradually declined through the decades (e.g. Pristimantis ridens, P. cruentus, Craugastor bransfordii) as in other well studied localities of Costa Rica, while some few species flourished after being almost absent from the site in the 1990s (e.g. Craugastor crassidigitus, Lithobates warszewistchii). Currently dominant species such as C. crassidigitus would be using developed resistance against Bd-fungus as an advantage (apparent competition) in the premontane forest where the disease is more virulent than in lowlands. Our analysis supports the hypothesis of individualized responses of anuran populations under distinct site and elevations. We suggest to continue monitoring the amphibian communities of premontane tropical forests to understand how this ecosystem gradually resist and adapts to this catastrophic time of biodiversity loss.
Priority research needs to inform amphibian conservation in the Anthropocene
(Wiley, 2023-07-19) Campbell Grant, Evan H.; Amburgey, Staci M.; Gratwicke, Brian; Acosta Chaves, Víctor; Belasen, Anat M.; Bickford, David; Brühl, Carsten A.; Calatayud, Natalie E.; Clemann, Nick; Clulow, Simon; Crnobrnja-Isailovic, Jelka; Dawson, Jeff; De Angelis, David A.; Dodd Jr, C. Kenneth; Evans, Annette; Ficetola, Gentile Francesco; Falaschi, Mattia; González Mollinedo, Sergio; Green, David M.; Gamlen Greene, Roseanna; Griffiths, Richard A.; Halstead, Brian J.; Hassapakis, Craig; Heard, Geoffrey; Karlsson, Catharina; Kirschey, Tom; Klocke, Blake; Kosch, Tiffany A.; Kusterko Novaes, Sophia; Linhoff, Luke; Maerz, John C.; Mosher, Brittany A.; O'Donnell, Katherine; Ochoa Ochoa, Leticia M.; Olson, Deanna H.; Ovaska, Kristiina; Roberts, J. Dale; Silla, Aimee J.; Stark, Tariq; Tarrant, Jeanne; Upton, R; Vörös, Judit; Muths, Erin
The problem of global amphibian declines has prompted extensive research over the last three decades. Initially, the focus was on identifying and characterizing the extent of the problem, but more recently efforts have shifted to evidence-based research designed to identify best solutions and to improve conservation outcomes. Despite extensive accumulation of knowledge on amphibian declines, there remain knowledge gaps and disconnects between science and action that hamper our ability to advance conservation efforts. Using input from participants at the ninth World Congress of Herpetology, a U.S. Geological Survey Powell Center symposium, amphibian on-line forums for discussion, the International Union for Conservation of Nature Assisted Reproductive Technologies and Gamete Biobanking group, and respondents to a survey, we developed a list of 25 priority research questions for amphibian conservation at this stage of the Anthropocene. We identified amphibian conservation research priorities while accounting for expected tradeoffs in geographic scope, costs, and the taxonomic breadth of research needs. We aimed to solicit views from individuals rather than organizations while acknowledging inequities in participation. Emerging research priorities (i.e., those under-represented in recently published amphibian conservation literature) were identified, and included the effects of climate change, community-level (rather than single species-level) drivers of declines, methodological improvements for research and monitoring, genomics, and effects of land-use change. Improved inclusion of under-represented members of the amphibian conservation community was also identified as a priority. These research needs represent critical knowledge gaps for amphibian conservation although filling these gaps may not be necessary for many conservation actions.
Effectiveness of personalized face-to-face and telephone nursing counseling interventions for cardiovascular risk factors: A controlled clinical trial
(2016-08-08) Vílchez Barboza, Vivian; Paravic Klijn, Tatiana María; Salazar Molina, Alide Alejandrina; Sáez Carrillo, Katia Lorena
Objective: to evaluate the effect and gender differences of an innovative intervention involving in-person and telephone nursing counseling to control cardiovascular risk factors (arterial hypertension, dyslipidemia, and overweight), improve health-related quality of life and strengthen self-efficacy and social support in persons using the municipal health centers' cardiovascular health program. Method: a randomized controlled clinical trial involving participants randomized into the intervention group who received traditional consultation plus personalized and telephone nursing counseling for 7 months (n = 53) and the control group (n = 56). The study followed the Consolidated Standards of Reporting Trials Statement. Results: women in the intervention group presented a significant increase in the physical and mental health components compared to the control group, with decreases in weight, abdominal circumference, total cholesterol, low-density lipoprotein cholesterol, and the atherogenic index. The effects attributable to the intervention in the men in the intervention group were increased physical and emotional roles and decreased systolic and diastolic pressure, waist circumference, total cholesterol, low-density lipoprotein cholesterol, atherogenic index, cardiovascular risk factor, and 10-year coronary risk. Conclusion: this intervention is an effective strategy for the control of three cardiovascular risk factors and the improvement of health-related quality of life.
Microsatellite development for Theridion evexum (Araneae: Theridiidae) using low-coverage genome sequencing and the MiMi script
(2025-09-15) Madrigal Brenes, Ruth; Barrantes Montero, Gilbert; Sandoval Vargas, Luis Andrés; Fuchs Castillo, Eric J.
Habitat fragmentation and unplanned urban expansion increasingly threatens biodiversity, yet the genetic impacts on arthropods, and particularly spiders, remains understudied due to the lack of suitable molecular makers. Here, we used low-coverage genome sequencing and a bioinformatics pipeline to develop polymorphic microsatellite markers for Theridion evexum, a tropical spider with urban and natural populations. To increase the yield of DNA extracted from small spiders like T. evexum, we also optimized a Cetyltrimethylammonium bromide (CTAB) DNA extraction protocol. We sequenced eight individuals at 4X using paired-end sequencing on an Illumina Novaseq 6000. Reads were cleaned and processed using the Multi-individual Microsatellite Identification (MiMi) python pipeline. MiMi produced a total of 3999 putative microsatellites. After filtering for polymorphic loci with an allelic richness greater than three and present in at least 5 of the 8 sequenced individuals, 34 final markers were identified. An experimental validation of 13 of these 34 markers showed that 10 loci were polymorphic with at least three detectable alleles, one locus was monomorphic, and two loci did not produce PCR products. These markers will allow a better assessment of the effects of urban fragmentation and isolation across populations of this spider species. Furthermore, developing markers using low-coverage next-generation sequencing (NGS) and bioinformatic protocols provide a valuable approach for uncovering microsatellite markers at a reduced cost for other tropical species, thereby broadening the scope of molecular ecology research in the tropics.