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Estado actual de las poblaciones de Lonchocarpus sanctuarii (Fabaceae) en Honduras

JOEL A. ORTEGA CESIA B. FLORES (2023, [Artículo])

Lonchocarpus sanctuarii, cono- cido popularmente como “chaperno negro’’ es un árbol nativo de Mesoamérica que se distribuye en México, El Sal- vador, Honduras y Nicara- gua. Esta especie habita en fragmentos de bosque seco subtropical y húmedo sub- tropical, y en Honduras se encuentran en el municipio Distrito Central y sus mayo- res amenazas son las expan- siones urbanas. Se realizaron giras de campo a tres sitios de las cinco poblaciones registra- das: UNAH-CU, Residencial La Cañada y la Colonia Hato de Enmedio. La mayoría de los individuos son brinzales (jóvenes) y las especies nati- vas con distribución restringi- da como L. sanctuarii son esenciales para mantener un equilibrio ecológico.

ADULTOS ABUNDANCIA BRINZALES DISTRIBUCIÓN HABITAT POBLACION NATIVA BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL

Determinación del habitat potencialmente utilizable por la especie Salmo trutta en un tramo del río Lozoya, España

EZEQUIEL GARCIA RODRIGUEZ Polioptro Martinez-Austria diego Garcia de Jalon LUIS ARMANDO OCHOA FRANCO (2009, [Artículo])

En el presente trabajo se efectúa la estimación del hábitat potencialmente utilizable y del caudal que lo maximiza para los estadios de vida adulto, juvenil, alevín y freza de la especie Salmo trutta (trucha común), especie muy apreciada en la pesca deportiva y para el consumo humano. Para tal fin, de acuerdo con la metodología IFIM (Instream Flow Incremental Methodology), se efectuó la simulación del hábitat físico fluvial de un tramo de 609 m del río Lozoya (Madrid, España) utilizando un modelo bidimensional de la hidrodinámica, un modelo para la simulación del hábitat y los modelos de preferencia de hábitat de la especie antes mencionada.

Ingeniería Hidráulica en México (0186-4076), 24(1) Ecosistemas fluviales Curva caudal-habitat Hidrodinámica fluvial Simulación INGENIERÍA Y TECNOLOGÍA

Insights into the transboundary stock structure of white seabass, Atractoscion nobilis, along the coast of California and Baja California

Perspectivas sobre la estructura del stock transfronterizo de la corvina blanca, Atractoscion nobilis, a lo largo de la costa de California y de Baja California

ARTURO FAJARDO YAMAMOTO (2023, [Tesis de doctorado])

The white seabass (Atractoscion nobilis) is a transboundary fishery resource that ranges from California, U.S., to Baja California Sur, Mexico, and within the north of the Gulf of California. It has been proposed two stock structure hypotheses that exist across their range in the eastern Pacific. However, still there are important data gaps to fill to understand the stock structure of this species. The aim of this study was to develop more information to understand the Pacific stock structure of the white seabass by (1) enhancing the baseline (catch-effort) information for the Mexican WSB fishery, (2) estimating the size-at-maturity and (3) describe the horizontal movement patterns and habitat utilization of adult WSB. Results suggest that the landings of the Mexican white seabass fishery showed an overall increase over the past 70 years. Landing fluctuations were associated with shifts in contextual factors, such as market changes and geopolitical events. For the past 20 years, the majority of harvest has come from Baja California Sur, with landings concentrated primarily in the fishery offices of Ciudad Constitución, Punta Abreojos, and San Carlos. White seabass females from southern Baja California mature at a size of 72.7 cm, while the males mature at a size of 58 cm. Moreover, regional differences of maturity were estimated where WSB from California matures larger than those from southern Baja California. A connectivity degree of white seabass adult was estimated between the coast of California and the west coast of the Baja California Peninsula. Overall, areas around islands and coastal areas are high-use areas for adult WSB. The Channel Islands, the region off Coronado Islands-Ensenada, the San Quintin region, and the Vizcaino Bay region are essential areas for WSB since different WSB ontogenic stages have been recorded. The spawning (March-September) and none spawning (October-February) seasons for adult WSB have marked differences in habitat utilization. Two migration pathways were estimated: one, a dispersal movement where adult white seabass moved northward to an area around the Channel Islands in California and a southward movement along the coast of the west coast of the Baja California Peninsula where multiple high-use areas were occupied and, second a return movement from north and south areas to a constrained and restricted area off the coast of Tijuana and San Quintin. Considering the information generated in this thesis, we have ...

La corvina blanca (Atractoscion nobilis) es un recurso pesquero transfronterizo que se extiende desde California, EE. UU., hasta Baja California Sur, México, y dentro del norte del Golfo de California. Se han propuesto dos hipótesis que describen la estructura del stock de la corvina blanca a lo largo de su área de distribución en el Pacífico oriental. Sin embargo, aún quedan vacíos en la información biológica-pesquera que nos permita comprender de una manera más robusta la estructura del stock. El objetivo de este estudio fue el desarrollar más información que nos permita comprender la estructura del stock de la corvina blanca que habita el Pacífico mediante (1) la reconstrucción de los desembarques de la pesquería mexicana, (2) la estimación del tamaño de madurez y (3) la descripción de los patrones de movimiento horizontal y el uso de hábitat de la corvina blanca adulta. Los resultados sugieren que los desembarques de la pesquería mexicana de corvina blanca mostraron un aumento en los últimos 70 años. Durante los últimos 20 años, la mayor parte de la captura proviene de Baja California Sur, concentrándose los desembarques en las oficinas pesqueras de Ciudad Constitución, Punta Abreojos y San Carlos. Las hembras de corvina blanca del sur de la Península de Baja California Sur maduran a una talla de 72,7 cm, mientras que los machos lo hacen a una talla de 58 cm. Además, se estimaron diferencias regionales de madurez, siendo que las corvinas blancas de California maduran a una talla mayor que las del sur de la Península de Baja California. Se estimó un cierto grado de conectividad de la corvina blanca adulta entre la costa de California y la costa oeste de la península de Baja California. En general, las áreas alrededor de las islas y las zonas costeras son zonas de alto uso para la corvina blanca adulta. Las islas del Canal, la región frente a las islas Coronado-Ensenada, la región de San Quintín y la región de la bahía Vizcaíno son zonas esenciales para la corvina blanca, ya que se han registrado diferentes fases ontogénicas en dichas zonas. El uso del hábitat de las corvinas blancas adultas durante la temporada de desove (marzo-septiembre) y la no desove (octubre-febrero) fue diferente. Se estimaron dos rutas migratorias: una, con movimientos de dispersión donde la corvina blanca adulta se desplazó hacia el norte alcanzando el área alrededor de las Islas del Canal en California, y un movimiento hacia el sur, a lo largo de la costa del litoral oeste...

White seabass, stock structure, landings reconstruction, size-at-maturity, habitat utilization Corvina blanca, estructura del stock, reconstrucción de desembarques, talla de madurez sexual, uso de hábitat CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS PECES Y FAUNA SILVESTRE DINÁMICA DE LAS POBLACIONES DINÁMICA DE LAS POBLACIONES

Biodiversity conservation in an anthropized landscape: Trees, not patch size drive, bird community composition in a low-input agroecosystem

ERIC MELLINK BIJTEL (2017, [Artículo])

One of the most typical agro-ecosystems in the Llanos de Ojuelos, a semi-arid region of central Mexico, is that of fruit-production orchards of nopales (prickly pear cacti). This perennial habitat with complex vertical structure provides refuge and food for at least 112 species of birds throughout the year. Nopal orchards vary in their internal structure, size and shrub/ tree composition, yet these factors have unknown effects on the animals that use them. To further understand the conservation potential of this agro-ecosystem, we evaluated the effects of patch-size and the presence of trees on bird community composition, as well as several habitat variables, through an information-theoretical modelling approach. Community composition was obtained through a year of census transects in 12 orchards. The presence of trees in the orchards was the major driver of bird communities followed by seasonality; bird communities are independent of patch size, except for small orchard patches that benefit black-chin sparrows, which are considered a sensitive species. At least 55 species of six trophic guilds (insectivores, granivores, carnivores, nectivores, omnivores, and frugivores) used the orchards. Orchards provide adequate habitat and food resources for several sensitive species of resident and migratory sparrows. The attributes that make orchards important for birds: trees, shrubs, herb seeds, and open patches can be managed to maintain native biodiversity in highly anthropized regions with an urgent need to find convergence between production and biological conservation. © 2017 Mellink et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

agroecosystem, carnivore, chin, conservation biology, driver, frugivore, granivore, habitat, human, insectivore, landscape, nonhuman, omnivore, orchard, resident, seasonal variation, shrub, sparrow, theoretical model, agriculture, animal, biodiversit CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Waterhole detection using a vegetation index in desert bighorn sheep (Ovis canadensis cremnobates) habitat

Jonathan Gabriel Escobar Flores (2019, [Artículo])

In arid ecosystems, desert bighorn sheep are dependent on natural waterholes, particularly in summer when forage is scarce and environmental temperatures are high. To detect waterholes in Sierra Santa Isabel, which is the largest area of desert bighorn sheep habitat in the state of Baja California, Mexico, we used the normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) from Sentinel-2 satellite images. Waterhole detection was based on the premise that sites with greater water availability, where NDVI was higher, can be identified by their density of vegetation greenness. For the detected waterholes, we estimated the escape terrain (presence of cliffs or steep, rocky slopes) around each by the vector ruggedness measure to determine their potential use by desert bighorn sheep based on the animals’ presence as documented by camera traps. We detected 14 waterholes with the NDVI of which 11 were known by land owners and 3 were unrecorded. Desert bighorn were not detected in waterholes with high values of escape terrain, i.e., flat areas. Waterhole detection by NDVI is a simple method, and with the assistance and knowledge of the inhabitants of the Sierra, it was possible to confirm the presence each waterhole in the field. © 2019 Escobar-Flores et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Article, bighorn sheep, environmental aspects and related phenomena, environmental parameters, habitat, Mexico, nonhuman, normalized difference vegetation index, normalized difference water index, water availability, waterhole, animal, bighorn sheep, CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS CIENCIA FORESTAL CIENCIA FORESTAL