Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Introduction: Bonellia nervosa is a dry forest understory tree with reverse leafing phenology (it produces leaves during the dry season and is deciduous during the wet season). Being a phreatophytic species, it relies on substantial root biomass to access groundwater and flush leaves during the dry season. Objective: assess the population structure of B. nervosa in Santa Rosa National Park, Costa Rica; analyze the relationship between stem diameter and plant height; and examine how canopy structure and light availability influence its local abundance. We also evaluated fruit maturity and pre-dispersal fruit predation during the late wet season to understand its reproductive success. Methods: the study was conducted along the Indio Desnudo trail (6.16 ha). Hemispherical photographs were taken above or near each B. nervosa (n = 33) and at 10 random sites where the species was absent. We used principal component analysis to consolidate seven light and canopy structural variables. The Chapman-Richards model was applied to examine the relationship between stem diameter and height and to identify inflection points. We analyzed fruit weight and seed count and inspected each fruit for the presence of Tortricidae larvae. Results: Adults dominated the population (only three seedlings were found out of 33 individuals). The Chapman-Richards model identified an inflection point at 70.6 cm in height, indicating a shift from relatively rapid to progressively slower growth. Bonellia nervosa sites had higher canopy openness (14.68 %) and transmitted diffuse light (21.05 μmol/m²/s) than sites where the species was absent (12.42 % and 18.22 μmol/m²/s, respectively). Predispersal fruit predation was low (16 % of fruits, n = 39), and was effected by Tortricidae larvae. Conclusions: Seedlings are likely limited by high energy demands for reserve accumulation, vulnerability to drought-related mortality, mechanical damage, and susceptibility to herbivory and pathogens. Their scarcity creates a recruitment bottleneck. The dominance of adults, the low number of seedlings, and specific light preferences limit the plasticity and adaptive capacity of B. nervosa to environmental changes. Although pre-dispersal fruit predation was low, further monitoring is needed to assess its full impact. Future research should focus on the physiological mechanisms underlying B. nervosa’s reverse leaf phenology and its resilience to climate change.

Introducción: Los bosques secos tropicales (BST) se encuentran entre los ecosistemas neotropicales más amenazados, caracterizados por una gran biodiversidad y endemismo, pero cada vez más amenazados por las actividades antropogénicas. En Colombia, particularmente en la región del Caribe, los BST se han fragmentado ampliamente. A pesar de su importancia ecológica, los estudios sobre las comunidades de miriápodos siguen siendo escasos. Los miriápodos, incluidos los ciempiés (Chilopoda) y los milpiés (Diplopoda), desempeñan un papel esencial en la dinámica del suelo y el ciclo de los nutrientes. Sin embargo, su diversidad y sus asociaciones ecológicas en los BSTs de Bolívar siguen siendo poco conocidas. Objetivo: Evaluar la diversidad y distribución de ciempiés y milpiés en fragmentos de TDF dentro de Bolívar y examinar su relación con variables ambientales. Métodos: El trabajo de campo se llevó a cabo en octubre y noviembre de 2020 en cuatro fragmentos de TDF en Turbaco, San Jacinto, Magangué y El Carmen. Las muestras se recolectaron mediante búsqueda libre, monolitos de suelo, trampas de caída y trampas Winkler, en parcelas de 50 × 50 m. Se realizaron identificaciones taxonómicas y análisis ecológicos. Resultados: Se registraron en total 1106 individuos, que comprendían ocho órdenes, 15 familias y 32 morfoespecies. Los diplópodos exhibieron mayor riqueza y abundancia que los quilópodos. Polydesmida y Spirostreptida fueron los órdenes de milpiés dominantes, mientras que Geophilomorpha fue el orden de ciempiés más abundante. La riqueza de especies fue mayor en San Jacinto y Turbaco, mientras que Magangué y El Carmen mostraron una menor diversidad, probablemente debido a perturbaciones antropogénicas. El análisis canónico de correspondencias reveló que el pH, la temperatura y la humedad del suelo influyeron significativamente en la distribución de las especies, lo que refuerza el papel de los miriápodos como bioindicadores. Conclusión: Este estudio proporciona la primera evaluación sistemática de la diversidad de miriápodos en los TDF de Bolívar, enfatizando su importancia ecológica y la urgente necesidad de esfuerzos de conservación.

Introduction: Orey swamp forests (Campnosperma panamense) are found on the Caribbean coast of Central America, from Nicaragua to Panama, and in the Pacific of Colombia to Northern Ecuador. In Panama, orey grows in monospecific stands or is the dominant species in inundated mixed forests, mainly along the coasts of Bocas del Toro province and Comarca Ngäbe-Buglé. The species was known to occur in Darien province, in the Pacific, although almost no information on its distribution and forest extension in the region existed. Objective: To describe the structure and floristics of orey forests in Darien, map their extension, and propose a model for their regeneration strategy. Methods: This work is part of a vegetation mapping project of the Matusagaratí complex of wetlands. It includes the use of drones, ground truthing, vegetation sampling through temporary plots, and general plant collecting. A supervised classification of a Landsat satellite image was performed to delimit the orey forest extension. To study the orey forest regeneration strategy, a digitalization of forest gaps in high resolution WorldView-2 and Planet Scope images over years was performed. Gap frequency and turnover time for forest stands were calculated. Results: Several monospecific orey mature forest patches were found in remote areas of the Matusagaratí complex of wetlands, for a total of 1 267 hectares. A description of the floristics and structure of orey forests in Darien is presented. A conceptual model of orey mature forest development and gap regeneration is proposed. Conclusions: Our knowledge of the floristic composition, structure and distribution of orey forests in the Republic of Panama has increased. For the first time, a model about their regeneration strategy is proposed. These forests seem to be evolving to different formations. Finally, some hypotheses are proposed about how they might respond to changing environmental conditions.

Introduction: The spotted rose snapper Lutjanus guttatus is one of the commercially most important fish species in tropical and subtropical areas of the Eastern Tropical Pacific. In Costa Rica, L. guttatus is one of the main target species of the artisanal fishery; traditionally, its management has considered a single population that extends along the entire coastal zone. However, there is no evidence that there is only one population unit, which could affect the effective management of this valuable resource. Objective: Determine the population structure of L. guttatus caught on the Pacific coast of Costa Rica through demographic parameters. Methods: A total of 428 specimens, collected in different zones along the Pacific coast of Costa Rica were analyzed, including 190 males and 238 females. The size structure, total length-weight relationship, maturity stages, mean size at sexual maturity, age and growth were estimated, differentiating between the Northern, central, and Southern Pacific of Costa Rica. Results: Demographic variations were observed in size structure, total length-weight relationship, the average size of sexual maturity, and growth rates among the organisms caught in the three sampling regions. Conclusion: The demographic variations of L. guttatus in the different capture areas suggest the probable existence of two separate population units; the first corresponds to the Northern Pacific, and the second includes the central and Southern Pacific areas. The above has important implications for the management of the resource.

Introduction: Marine macroalgae exhibit a wide variety of shapes and sizes, influencing habitat preferences for various organisms, including polychaetes and sipunculans. Objective: To evaluate the relationship between the richness and abundance of polychaetes and sipunculans with red, green, and brown marine macroalgae using specimens collected in Isla Cayo Serrana, Colombian Caribbean, deposited at the Colecciones Biológicas de la Universidad CES (CBUCES). Methods: To estimate the richness and abundance of polychaetes and sipunculans associated with macroalgae, the specimens were separated from each batch of macroalgae. Also, a χ2 test was performed to evaluate if there was an association between annelids and macroalgae. In addition, some morphological measurements were taken for green and red algae, and the relationship between algae morphological complexity and richness and abundance of polychaetes was assessed using Spearman’s correlation coefficient. Results: A total of 460 polychaetes and eight sipunculans were recorded in this study, distributed in 42 species. The polychaete family with the highest richness and abundance was Syllidae, whereas in sipunculans was Phascolosomatidae. Herein, we did not find an association between red, green, and brown macroalgae regarding the richness and abundance of polychaetes and sipunculans. However, a correlation (ρ 0.56–0.78, p < 0.03) was found between some morphological measurements of width, leaf area, wet weight, and displaced volume of green macroalgae of the genus Halimeda with the polychaetes richness and abundance. In contrast, there was no correlation between measurements of red macroalgae (Jania and Amphiroa) and polychaete richness and abundance (ρ between -0.1 and 0.39). Conclusions: This study underscores the relevance of specific morphological attributes of green macroalgae (Halimeda) in enhancing polychaete richness and abundance.

Introduction: The size, density, and composition of primate social groups are essential for understanding group dynamics and determining population management plans for primate conservation. Objective: To determine the size, density, and composition of howler monkeys (Alouatta palliata) and white-faced monkey (Cebus imitator) groups in dry forest environments and areas of reduced canopy in Palo Verde National Park, Costa Rica. Understanding how these species respond to different environments has important implications for conservation and reforestation efforts. Methods: Field sampling was carried out during February 2023 during the peak hours of primate activity (6:00-12:00 and 14:00-18:00). The individuals of both primate species were counted, recognizing the groups found in both types of environments (dry forest and reduced canopy areas). Results: Howler monkey group sizes were significantly larger in dry forests and at a higher percent of canopy cover. As for white-faced monkeys, a higher density was recorded in dry forests compared to the last census in 1987. Conclusion: Greater availability of resources (abundance of food and shelter sites) in closed environments favors the presence of a greater number of howler monkeys. Our analyses show that group size in this primate species depends on the type of environment. This study highlights the importance of long-term monitoring and studies of these parameters in wild primate groups.

Introduction: The birds in tropical cities are subject to changes in community composition and structure based on landscape properties and habitat heterogeneity. Urban landscapes offer a set of fragmented habitats restricting dispersion and promoting the metacommunity structure of birds. Objective: To analyze the structure of an urban bird community with a meta-community perspective. Methods: With a spatial array of 60 bird sampling points between May 2015 and February 2016, and estimations of landscape metrics with a satellite image classification, we measured the coherence, turnover, and boundary clumping of three subsets of birds to fit a metacommunity structure pattern and correlate with landscape properties of Tuxtla Gutierrez, a neotropical city with potential for bird conservation. Results: The bird species composition comprises a dominant subset of exotic and synurbic species, another of resident abundant species, and one of rare native species. The dominant species seem to be determined by a Clementsian structure, associated with a bird community with a similar response to the environmental gradient. Both dominant and rare species showed a nested structure associated with environmental filtering processes, such as the amount of available habitat. The occurrence and distribution of abundant to rare species composition were associated with the amount of natural vegetation cover, whereas the dominant species abundance with the extension of urban coverage. Conclusions: The bird species composition in urban landscapes of tropical dry forest regions can be structured as a metacommunity in response to a gradient of vegetation fragmentation due to anthropogenic changes. Synurbic and native species do not show a homogenization of diversity composition. To ensure the conditions for bird diversity conservation in tropical urban landscapes, knowledge of the correlation of landscape elements with community structure and habitat conditions in fragmented environments is needed.

Introduction: Functional diversity is crucial in understanding species performance and monitoring ecological restoration processes. In Valle del Cauca, Colombia, where only a small percentage of tropical dry forest remains, ongoing ecological restoration efforts are vital. However, monitoring of restoration efforts is typically not conducted. Objective: To compare the functional diversity of two plant communities, restored two and eight years ago, in the Loma Larga reserve, Colombia. Methods: We assessed nine functional traits in the five most significant species of each community. The analysis included contrast tests for functional trait differences, as well as functional diversity indices. Results: The 8-year community displayed greater values for maximum height, diameter at breast height, and specific leaf area. Conversely, the 2-year community exhibited higher leaf thickness. Moreover, the 8-year community presented the highest values in the functional indices: richness, evenness, divergence, dispersion, and specialization. Conclusions: Ecological restoration had a positive impact on plant communities, as evidenced by increased functional diversity and structural complexity in the 8-year community compared to the 2-year community. This suggests that ecological succession processes advance significantly over time, leading to more resilient and functionally diverse communities. The analysis of functional traits stands out as an effective tool for monitoring the success of restoration and guiding future efforts in critically threatened ecosystems such as tropical dry forests.

Introduction: The Magdalena River in Colombia has a high anthropic intervention, and this high load of pollutants that enter mainly in the middle and upper basin of its course are becoming increasingly noticeable in the lower basin. Objective: This study evaluated the environmental condition of a section of the Magdalena River in the lower basin as it passes through the Department of Atlántico, using the Ecological Quality Index (EQI) based on phytoplankton. Methods: Six sampling events were carried out between 2021 and 2022, in order to cover contrasting moments of the hydrological regime, at six monitoring stations on the Western bank of the river. Physicochemical and phytoplankton variables were sampled to establish reference categories based on the EQI. Results: Conductivity was determined as the variable that explained the greatest variation in the environmental gradient, generating reference ranges to establish categories of poor, fair and good ecological quality. 77 phytoplankton morphospecies were recorded, of which five were sensitive to the physicochemical conditions of the Magdalena River, with high optimum values and low tolerance limits: Pinnularia sp2, Diatoma sp3, Navicula sp1, Closterium limneticum, C. rostratum. Conclusions: In general, the Magdalena River in the Atlántico showed a fair ecological quality condition, which deteriorated even more during the dry periods of the year. The EQI showed a relationship with the proportion of diatom groups and the abundance of phytoplankton, obtaining better quality values when diatoms predominate over the cyanobacteria group and when the abundance of the phytoplankton is relatively low.

Introduction: Turtles are extensively harvested to supply the demand for food, pets, and products. Conservation strategies often involve the release of seized individuals and ex-situ breeding programs. However, several traded species have particular genetic characteristics, and the origins of captive individuals are often unknown. Despite their potential to aid in the recovery of populations, these strategies have faced criticism due to the risk of outbreeding depression and genetic diversity loss. Objective: To explore the use of mitochondrial sequencing to estimate the origin of captive individuals from three of Colombia's most traded turtle species: Chelonoidis carbonarius, Trachemys venustacallirostris, and Rhinoclemmys melanosterna. Methods: Firstly, we constructed genetic reference databases using 350 sequences from previous phylogeographic studies and new ones from individuals with known origins. Secondly, through phylogenetic and population genetics analyses we delimited phylogeographic groups. Thirdly, we compared the sequences of 157 turtles of unknown origins, successfully assigning them to their species and the most likely areas of origin. Results: We identified genetic structure in wild populations, heterogeneity of origins in captive individuals, and complex trade networks involving harvesting from multiple distant poaching areas and transportation to central regions. Conclusions: This study shows the efficacy of mitochondrial molecular markers in determining the possible region of origin for confiscated turtle individuals affected by illegal trade and emphasizes the importance of intra-specific conservation efforts to safeguard Colombian wildlife’s genetic identity and diversity.