Browsing Artículos científicos by Title
Now showing items 288-307 of 331
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Scorpion maintenance in captivity for venom extraction in Costa Rica
(Revista de Biologia Tropical Vol.64 No.3 1019-1027, 2016-04-04)Approximately 2 000 scorpion species can be found around the world; although few species are considered “harmful” to human beings, a high number of scorpionism cases are reported all over the world. The ... -
Seasonal changes of phytoplankton in the Paquera-Tambor Marine Area for Responsible Fishing, Gulf of Nicoya, Costa Rica
(Universidad Nacional (Costa Rica), 2016-07)The implementation of Marine Areas for Responsible Fishing (MARF) is a tool for fisheries management; therefore, baseline studies play an important role in understanding the ecological dynamics from the bases of the food ... -
Seasonal Guild Variation of a Bat Assemblage in an Agricultural Landscape of a Tropical Dry Forest of Costa Rica
(Instituto Tecnológico de Costa Rica, 2019-07)In Costa Rica, the tropical dry forest is restricted into the North Pacific, being one of the few remnants of the Mesoamerican dry forest. This forest presents remarkable climatic variation throughout the year, especially ... -
Seasonal impact of grazing, viral mortality, resource availability and light on the group‑specifc growth rates of coastal Mediterranean bacterioplankton
(Nature Research, 2020-12)Estimation of prokaryotic growth rates is critical to understand the ecological role and contribution of diferent microbes to marine biogeochemical cycles. However, there is a general lack of knowledge on what factors ... -
Simulación de una cohorte de Anchoa Panamesis (Steindachner, 1975) en el Golfo de Nicoya, Costa Rica
(Universidad Nacional [Costa Rica], 1987-01-01)Se aplica el modelo de simulación de stock de Jansen a una cohorte hipotético de 100.000 peces de Anchoa panamensis, utilizando una tasa de mortalidad natural de 0.274 mensual, obtenida para esta población en 1981 y dos ... -
Skin texture change in diasporus hylaeformis (Anura: Eleutherodactylidae
(Sociedad Herpetologica Mexicana, 2020-11)La Rana Martillito de Altura, Diasporus hylaeformis, fue observada mostrando un cambio de textura de la piel durante una sesión fotográfica. Se ha sugerido que este comportamiento, reportado recientemente en anuros, puede ... -
Snake diversity (squamata: Serpentes) in Quebrada González sector of Braulio Carrillo National Park, Costa Rica
(Malcolm L. McCallum, 2019-04-30)Within Braulio Carrillo National Park (BCNP) of Costa Rica, there is a lack of quantitative data regarding the snake community despite its informally reported abundance and relevance to human health. The objective of this ... -
Social effects in growth experiments. Growth of jaguar guapote (Cichlasoma managuense) in isolation and in small groups
(Universidad Nacional (Costa Rica), 1997)Se evaluaron el crecimiento y la conversión alimenticia de juveniles de guapote tigre (Cichlasoma managuense) mantenidos a densidades constantes de 1, 2, 5, 10 y 20 individuos por pecera. La densidad mostró una correlación ... -
Spontaneous spawning in captivity of the first generation hatchery-produced weakfish, Cynoscion squamipinnis (Perciformes: Sciaenidae)
(Universidad Nacional (Costa Rica), 2017-01)The aim of this study was to evaluate the spontaneous spawning of the first generation of weakfish (Cynoscion squamipinnis) reared in captivity in order to conduct restocking programs and mariculture projects. Juveniles ... -
Spontaneous spawning, ontogeny and growth in captivity of Cynoscion squamipinnis
(Universidad de Costa Rica, 2016-09-03)The croakers or drums are commercial species, which have been overfished in the Nicoya Gulf, Costa Rica. This study aimed to describe, for the first time, the reproduction and the ontogeny of weakfish, Cynoscion squamipinnis ... -
Spotted rose snapper (Lutjanus guttatus) aquaculture research and development as socio-economic alternative for Costa Rican fishing communities
(2010-06-01)The spotted rose snapper (Lutjanus guttatus) is one of the main target coastal species, but landings are decreasing in quantity and size. Reports include a mean capture size of 50 cm with gill nets and 38 cm with bottom ... -
Strategy of bioremediation in recirculating aquaculture systems using constructed microbial mats
(Journal of Chemical, Biological and Physical Sciences, 2014-11-30)Due to strict international standards, every day there is greater interest in developing environmentally sound treatment systems in aquaculture facilities that can remove contaminants from effluent and allows for the reuse ... -
Tamaños y proporción sexual de Ucides occidentalis (Crustacea: Gecarcinidae) en un manglar de Costa Rica
(Universidad Nacional (Costa Rica), 1995-02-22)Sizes and sex ratios of Ucides occidentalis (ORT-MANN 1897) were studied in the mangrove area of Estero Panama, Guanacaste, Costa Rica, from March to August 1982. The caparace length was 36.7-84.5 mm for males and 36.00-60.8 ... -
Tendencias en las concentraciones de nitratos y determinación de sus orígenes usando isótopos estables (18O y 15N) en el agua subterránea de la parte oeste del Valle Central, Costa Rica
(2013-08-22)El nitrato es el contaminante más común en el agua subterránea y se deriva principalmente de la lixiviación de fertilizantes sintéticos y desde sistemas in situ de disposición de aguas negras, especialmente en áreas con ... -
Teorías y modelos aplicados al estudio de la conducta del pescador: implicaciones en procesos de gestión
(Universidad Nacional (Costa Rica), 2017-01)En el proceso de toma de decisiones para el manejo de pesquerías se ha incrementado la atención en considerar aspectos de la dimensión humana de la pesca adicionalmente a la dimensión ecológica. En la dimensión humana, el ... -
The effect of high rearing densities on the growth of juveniles of the cichlid, cichlasoma managuense
(Universidad Nacional, Costa Rica, 1992-01-01)The effect of high density culture on the growth of juvenile jaguar cichlids was investigated. Mean growth rate decreased with density, while the growth rate of the largest fishes was not affected. Reduction in mean growth ... -
The effect of Ibuprofen on female and male reproduction of the open thelyca marine shrimp, Litopenaeus
(Aquaculture Research, 2013-03-11)A research was designed to explore the effect of ibuprofen (IBU) as an intervening agent for prostaglandin biosynthesis on male and female reproduction of three species of Litopenaeus. Ovarian maturation was studied in L. ... -
The first gynandromorph of the Neotropical bee Megalopta amoena (Spinola, 1853) (Halictidae) with notes on its circadian rhythm
(Pensoft Publishers, 2020-04-27)Gynandromorphy is an anomaly that results in an organism phenotypically expressing both male and female characteristics. Here we describe the first gynandromorph of the bee species Megalopta amoena (Spinola, 1853) (Halictidae, ... -
The geographic distribution of Costa Rican velvet worms (Onychophora: Peripatidae)
(Revista de Biologia Tropical vol.64 no.4 1401-1414 2016, 2016-06-06)Velvet worms, “peripatus” or onychophorans, are “living fossils” that were geographically widespread in Cambrian seas but now occur exclusively on terrestrial habitats. The only extant species studied in some detail are ... -
The growth of juvenile jaguar guapote (Cichlasoma managuense) fed diets with different carbohydrate levels
(Universidad Nacional (Costa Rica), 1995-06-27)Se evaluó el crecimiento de juveniles del guapote tigre (Cichlasoma managuense) alimentado con dietas isocalóricas conteniendo niveles de carbohidrato del 11 al 36 por ciento. El experimento se realizó en un sistema de ...
