Biology subjects

Calderon, E.

Publications and source records attributed to Calderon, E..

2 recordsLinked to original sources

bioRxiv2025

Distribution patterns of aquatic birds in a high-Andean wetland in southeastern Peru: an approach based on environmental factors

High-Andean wetlands play a crucial role in the conservation of avian biodiversity, acting as ecological oases amidst the arid Andes. However, these ecosystems face increasing anthropogenic and climatic pressures, jeopardizing both the ecosystem services they provide and the biodiversity they harbor. Moreover, research on these ecosystems remains scarce, limiting the knowledge necessary for their effective conservation. This study, conducted in Lake Piuray in the southeastern Andes of Peru, investigated the spatial and temporal distribution patterns of aquatic birds, assessing the influence of environmental variables such as depth and chlorophyll-a content. From December 2022 to November 2023, monthly surveys were carried out at 13 counting points distributed across four zones of the lake, encompassing natural and altered habitats such as lakeshore beaches and cultivated areas. Distribution maps were generated using weighted interpolation models and additive models to analyze non-linear relationships between bird abundance and environmental variables. Additionally, differences between seasons (wet and dry) and the evaluated zones were analyzed using non-parametric tests. A total of 43 aquatic bird species were recorded, with 19,768 individuals. Areas with low depth (<15 m) and intermediate to high levels of chlorophyll-a (I543 index: 0.20-0.25) concentrated the highest abundance and species richness. Zones with lakeshore beaches showed greater abundance and richness, while deeper zones exhibited the lowest values. At the family level, shorebirds preferred shallow waters, and diving birds tolerated greater depths. Although no significant differences in richness, abundance, and diversity were found between seasons at the community level, differences were identified in six families, with variations in their abundance between the wet and dry seasons. These results highlight the importance of shallow areas with high chlorophyll-a concentrations for the conservation of aquatic birds in high-Andean wetlands. This study is one of the few to analyze the influence of environmental and temporal factors on the distribution of high-Andean aquatic birds, and its representative nature makes it a valuable model for identifying priority areas for the conservation of these species.

ecology↗

bioRxiv2020

The genomes of invasive coral Tubastraea spp. (Dendrophylliidae) as tool for the development of biotechnological solutions

Corals have been attracting huge attention due to the impact of climate change and ocean acidification on reef formation and resilience. Nevertheless, some species like Tubastraea coccinea and T. tagusensis have been spreading very fast replacing the native ones which affect the local environment and decrease biodiversity of corals and other organisms associated with them. Despite some focal efforts to understand the biology of these organisms, they remain understudied at the molecular level. This knowledge gap hinders the development of cost-effective strategies for both conservation and management of invasive species. In this circumstance, it is expected that genome sequencing would provide powerful insights that could lead to better strategies for prevention, management, and control of this and other invasive species. Here, we present three genomes of Tubastraea spp. in one of the most comprehensive biological studies of corals, that includes flow cytometry, karyotyping, transcriptomics, genomics, and phylogeny. The genome of T. tagusensis is organized in 23 chromosomes pairs and has 1.1 Gb, the T. coccinea genome is organized in 22 chromosome pairs and has 806 Mb, and the Tubastraea sp. genome is organized in 21 chromosome pairs and has 795 Mb. The hybrid assembly of T. tagusensis using short and long-reads has a N50 of 227,978 bp, 7,996 contigs and high completeness estimated as 91.6% of BUSCO complete genes, of T. coccinea has a N50 of 66,396 bp, 17,214 contigs and 88.1% of completeness, and of Tubastraea sp. has a N50 of 82,672 bp, 12,922 contigs and also 88.1% of completeness. We inferred that almost half of the genome consists of repetitive elements, mostly interspersed repeats. We provide evidence for exclusive Scleractinia and Tubastraea gene content related to adhesion and immunity. The Tubastraea spp. genomes are a fundamental study which promises to provide insights not only about the genetic basis for the extreme invasiveness of this particular coral genus, but to understand the adaptation flaws of some reef corals in the face of anthropic-induced environmental disturbances. We expect the data generated in this study will foster the development of efficient technologies for the management of coral species, whether invasive or threatened.

evolutionary biology↗