Central Pacific Of Costa Rica Research Articles

Historical analysis of timber exploitation in the Central Pacific Mountains of Costa Rica

Abstract [Introduction] The mountainous region of the Central Pacific of Costa Rica, currently made up mostly of the cantons of Turrubares, Puriscal and Mora, and to a lesser extent by the southwest of Acosta, was one of the most deforested areas since colonial times. [Objective] To comprehensively analyze the historical, socioeconomic, geo-climatic and ecological factors that possibly favored the logging exploitation of the forests of that region. [Methodology] The historical documents, and the geo-climatic, ecological and socioeconomic factors of the region were reviewed. In addition, a census was carried out among forestry professionals and industrialists to determine the timber species possibly extracted from the forests based on the floristic composition of protected forest areas in the region. [Results] The mountainous region was a transit and settlement site for Spanish colonists since the 16th century, which facilitated the development of access roads. Its proximity to the Central Valley, which needed forest and agricultural products for the growing urban area, together with the existence of an ecological convergence zone extraordinarily rich in trees of commercial importance, greatly facilitated the extraction of forest products. [Conclusion] The early colonization of the region, the existence of infrastructure, high demand for forest products at the national and international level, and the availability of forest resources in an area where the tropical dry forest, the cloud forest and the humid forest converge, and the edaphoclimatic conditions that also facilitated the development of agricultural crops, favored the change in land use and therefore the forestry exploitation of the region.

Multivariate data analysis applied to groundwater geochemical characterization, Central Pacific, Costa Rica

This research has allowed to provide new information about the geochemical groundwater composition in the Central Pacific of Costa Rica, a place with an important commercial, touristic, and real estate development with a continues water resource demand. Previous reports of iron and manganese elevated concentrations, and flow water rate decrease in production wells, turn the area into an object of hydrogeological studies as the resource demand increases. The main objective of this research was to provide information about the quality and composition of the groundwater, and to understand the relationship with the geological and structural context. A total of 25 groundwater samples were collected, subsequently hierarchical clustering method were applied to analyze chemical concentrations and characterized the groundwater. Results showed some samples with atypical trace elements concentrations such as Al, Mn, and Fe, which are above the water quality limits. After applied the hierarchical clustering, results evidence the presence of two main clusters, which one cluster have samples with high temperatures and mineralized waters in common. The groups are distributed between three major neotectonics faults Barranca, Jesús María, and Tárcoles that creates a complex structural context that provides pathways movement for the contribution of thermal waters which can strongly dissolve the rocks, and provide a certain water chemical composition related with the presence of volcanic rocks with high concentrations of K, Mg, Mo, P, Rb, Si, Fe, Mn, F and U, and sedimentary rocks with high concentrations of B, Ba, Ca, Cu, Fe, Ge, Li, Na, S, SO4 and Zn.

Trends and variability in local abundances of sailfish Istiophorus platypterus in Pacific waters of Costa Rica: Controls and effects on recreational fisheries

Fishing tourism represents a vital industry in Costa Rica, generating over US$520 million and attracting 150,000 tourists every year. The main objective of this study is to examine trends and variability in local abundances of sailfish Istiophorus platypterus, the main sportfish in Pacific waters of Costa Rica, and quantify the influence of environmental and anthropogenic factors. We compiled and analyzed sailfish information collected from sportfishing operations. Sailfish abundances were examined in relation to environmental conditions and commercial fishing. Timeseries analyses showed significant declining trends in local abundances of sailfish in the southern and central Pacific of Costa Rica over the last decade. Bycatch records from the commercial purse seine fleet operating in Costa Rican waters also show a declining trend in sailfish numbers. On the other hand, commercial landings from the national longline fleet show a significant increase of 108%, on average, over the past decade. Different numerical models indicated that fishing pressure from the national fleet and also sea surface temperature with different time lags affect local abundances of sailfish. While other countries in Central and North America protect sailfish and other species of tourist interest, Costa Rica still allows the landing and sales of billfishes as seafood. The results presented in this study highlight the need to allow for the recovery of local abundances of sailfish and promote the development of the coastal communities that depend on marine tourism as their main source of income.

Quantification and Evaluation of Water Requirements of Oil Palm Cultivation for Different Climate Change Scenarios in the Central Pacific of Costa Rica Using APSIM

Climate change is a variation in the normal behavior of the climate. These variations and their effects will be seen in the coming years, the most imminent being anomalous fluctuations in atmospheric temperature and precipitation. This scenario is counterproductive for agricultural production. This study evaluated the effect of climate change on oil palm production for conditions in the Central Pacific of Costa Rica, in three simulation scenarios: the baseline between the years 2000 and 2019, a first climate change scenario from 2040 to 2059 (CCS1), and a second one from 2080 to 2099 (CCS2), using the modeling framework APSIM, and the necessary water requirements were established as an adaptive measure for the crop with the irrigation module. A decrease in annual precipitation of 5.55% and 7.86% and an increase in the average temperature of 1.73 °C and 3.31 °C were identified, generating a decrease in production yields of 7.86% and 37.86%, concerning the Baseline, in CCS1 and CCS2, respectively. Irrigation made it possible to adapt the available water conditions in the soil to maintain the baseline yields of the oil palm crop for the proposed climate change scenarios.

A Sea Breeze Study during Ticosonde-NAME 2004 in the Central Pacific of Costa Rica: Observations and Numerical Modeling

Surface and upper air observations and MM5v3 simulations examined the structure and inland penetration of sea breeze (SB) along the Grande de Tárcoles river basin (GTRB), central Pacific, Costa Rica, for two different intensity regimes of the Caribbean Low-Level Jet (CLLJ). Data comprise the period of 1 July to 16 September 2004 from Ticosonde-North American Monsoon Experiment, and a local University of Costa Rica-National Meteorological Institute field campaign. Maximum precipitation occurs between 14:00–17:00 LST, showing a time lag of 2 to 3 h after the temperature maximum, suggesting that local diurnal heating is key to convection. July–August precipitation exhibited a rainfall decrease along GTRB due to the SB dynamical processes interaction with a strong CLLJ. The SB maximum inland incursion was 24 km, with no evidence of its penetration into the Central Valley. The MM5v3 simulations for two convective and boundary layer (BL) schemes captured some SB structure features along the GTRB. Comparison of model results with observed data shows deficiencies in the model representation of the surface flow near coastal regions. Differences may be the result of time lag model’s poor responses to actual early morning BL sea–land temperature gradients. MM5v3 configurations used in this study resulted in biased wind speed simulations.

Microplastic ingestion by a herring Opisthonema sp. in the Pacific coast of Costa Rica

Current knowledge of the presence of microplastics (MP) in marine species in tropical areas is still limited. The presence of MP was examined in the gastrointestinal content of 30 filter feeders of the herring Opisthonema complex (Clupeiformes: Clupeidae) from the Central Pacific of Costa Rica. MP were detected in 100% of the individuals with an average of 36.7 pieces per fish, of which 79.5% were fibers and 20.5% particles. No direct association between biometric variables or sex and the amount of microplastic was found. Different physicochemical analyses were carried out to determine the composition and characteristics of the microplastics. Most of the fibers were classified as polypropylene. Remarkably, some plastic particles turned out to be composed exclusively of minerals. This study demonstrates the high presence of MP in planktivorous fishes of the Pacific coast of Central America. Also, we propose the Opisthonema complex as a model for biomonitoring microplastic pollution in the Tropical Eastern Pacific due to its wide distribution, biometric homogeneity of the schools, non-selective feeding type, and its crucial position in the marine food webs.

Hydrogeological vulnerability in Jacó coastal aquifers, Central Pacific, Costa Rica

In the last two decades, the Central Pacific of Costa Rica experienced a strong growth in urban and tourism development. If not regulated, this development can result in a pressure to groundwater resources and, therefore, a threat in terms of quality and quantity. In this study, a hydrogeological vulnerability map of Jacó aquifers was performed, by the GOD method. Geological profiles were elaborated, and field verification was performed. It is confirmed that, in the study area, two aquifers are found: a) a detritic, porous, unconfined coastal aquifer, settled in the Jacó alluvial plain and, b) an aquifer in the basaltic fractured rocks of the Nicoya Complex, unconfined in the mountainous zone and underlying the detritic formation in the central area, where the groundwater is integrated to that of the detrital aquifer. The zone of the alluvial aquifer resulted in a medium vulnerability index, whereas the mountainous areas in a low vulnerability. Management recommendations were proposed.

Influencia de la vigilancia en una zona rocosa dentro de un área marina protegida, Pacífico Central de Costa Rica

We present the results of conservation assessment of a rocky shore in the Central Pacific of Costa Rica (Playa Hermosa-Punta Mala National Wildlife Refuge) using the biological indicators proposed by the national environmental ministry. This study aims to analyze the influence of surveillance, between two sites, over the rocky shore habitat. The sampling was carried out during both the dry and rainy seasons in 2015. Our data shows that Nerita scabricosta -harvested in small-scale fisheries- presents a high number of colonies formed by few individuals. Moreover, the abundance varied between seasons, probably due to a storm surge. Macroalgae differed slightly among sites, where turf had higher percentage coverage in low surveillance areas, while brown algae had higher coverage in high surveillance areas. Mechanical damage (abrasion due to rocks overturning) associated with tourism and harvesting could be influencing the low surveillance area, explaining these differences. Macroalgae presented a seasonal change, probably related to the storm surge. The density of the Tetraclita stalactifera did not exhibit variations. The surveillance level and enforcement influenced some bioindicators of the rocky shore, and therefore could be used to assess the extractive pressure.

The community of Mata de Limón, central Pacific coast of Costa Rica and the extraction of colonchos Callichirus seilacheri (Bott, 1955) (Decapoda: Axiidea: Callianassidae)

We conducted monthly visits to the coastal community of Mata de Limón (December 2011 to November 2012) in central Pacific of Costa Rica for assessment the extraction of the burrowing shrimp called coloncho Callichirus seilacheri, a species intensely caught as bait for fishing along the Pacific coast of Central America. The outcomes indicate that fishery effort varied between 4 and 14 harvesters day-1 with a high percentage of them from the same community (70-100%). Daily catch varied between 76 and 1120 shrimps and its value was strongly correlated with catches realized for the local harvesters (R2= 0.88). The shrimps density and total abundance in Mata de Limón was estimated in 1.2 ± 0.88 ind m-2 and 49,607 ± 3,638 individuals, respectively. Ovigerous females were exclusively present between May and November, peak in September. According to our outcomes, population of C. seilacheri in Mata de Limón could be in risk of overfishing if the daily catches exceed 800 individuals. The main results of the present study allow recommend the implementation of a total fishing ban during the reproduction peak of C. seilacheri directed to protection and conservation of this local resource for its sustainable harvesting. Also, we suggest the establishment of a management program between the community of Mata de Limón and the Instituto Costarricense de Pesca y Acuicultura (INCOPESCA) in order to optimize and legalize the extraction of this important resource.

A checklist of the amphibians and reptiles of San Isidro de Dota, Reserva Forestal Los Santos, Costa Rica

We present an inventory of amphibians and reptiles of San Isidro de Dota, northwest of the Cordillera de Talamanca in the Central Pacific of Costa Rica. The study was conduced from January to August 2012 in premontane wet forest from 689 m to 800 m elevation. We found a total of 56 species, including 30 species of amphibians and 26 of reptiles. It results striking the presence of the frog Leptodactylus insularum , uncommon above 400 m elevation, and the lizard Coloptychon rhombifer , a very uncommon species.

Beach almond (Terminalia catappa, Combretaceae) seed production and predation by scarlet macaws (Ara macao) and variegated squirrels (Sciurus variegatoides).

Knowledge of ecological impacts of exotic beach almond (Terminalia catappa) in the central Pacific of Costa Rica are little known, but studies have found this species to be a potentially important food source for endangered scarlet macaws (Ara macao). In this study, reproductive phenology and seed predation by variegated squirrels (Sciurus variegatoides) and scarlet macaws were measured during March and April 2011 on beaches of central Pacific coastal Costa Rica. Seed productivity and predation levels were quantified on a weekly basis for 111 beach almond trees to assess the importance of beach almond as a food source for scarlet macaws and the extent of resource partitioning between seed predators. Seed production of the trees was great (about 194 272 seeds) and approximately 67% of seeds were predated by seed predators. Macaws consumed an estimated 49% of seeds while squirrels consumed 18%. Additionally, evidence of resource partitioning between squirrels and macaws was found. Scarlet macaws preferred to feed on the northern side and edge of the canopy while squirrels preferred to feed on the southern and inside parts of the canopy. Both species ate most seeds on the ocean side of the tree. Despite the status of this tree as an exotic species, the beach almond appears to be an important resource for scarlet macaw population recovery. The resource produced by this tree should be taken into account as reforestation efforts continue in Costa Rica.

Crecimiento y desempeño fotosintético de cinco plántulas de especies arbóreas en respuesta a regímenes lumínicos naturales del Pacífico Central de Costa Rica

Environmental heterogeneity mostly dominated by differing light regimes affects the expression of phenotypic plasticity, which is important for plant growth and survival, especially in the forest understory. The knowledge about these responses to this heterogeneity is a key factor for forest restoration initiatives. In this study, we determine several phenotypic responses to contrasting light conditions in five native tree seedling species of La Cangreja National Park, Central Pacific of Costa Rica, four of them with threatened or relict populations. After 14 weeks at a medium gap condition (24% of full sun), seedlings were transferred and acclimated for 11 weeks to three different natural light regimes: large gap (LG), medium gap (MG) and small gap (SG), corresponding to 52%, 24%, 9% of the mean direct and indirect radiation at each site from full sun. Growth, biomass allocation and leaf gas exchange were measured after the acclimation period. Four species strongly reduced relative growth rate (RGR) in the lower light condition. Total biomass (TB) and RGR were different in Hymenaea courbaril and Platymiscium curiense. H. courbaril and Astronium graveolens had significant changes in the maximum assimilation rate, with a mean value in the LG of 11.02 and 7.70 micromolCO2/m2s, respectively. P. curuense showed the same trend and significant changes in RGR and biomass allocation. Aspidosperma myristicifolium and Plinia puriscalensis showed no adjustments to the light regimes in any of the measured variables. This study remarks the importance of determining the growth and physiological performance of these tree native species. It also demonstrates that the most threatened species are those with the less plastic responses to the light regimes, which stresses the difficult situation of their natural populations. This study highlights an urgent definition of the conservation and restoration needs of the degraded forests of the Costa Rican Central Pacific area, where these species dwell.

Tectonic evolution and sequence stratigraphy of the Central Pacific margin of Costa Rica

On the Central Pacific of Costa Rica, more than 1600 km of seismic reflection data, and potential field data, located offshore and onshore, joined to the surface geology data have been analyzed in order to clarify the structural configuration, tectonic evolution and characteristics of the sedimentary infill. Two main depocenters are recognaized in the area: the Nicoya basin comprising about 3.5 km of Cretraceous-Tertiary sediments in the offshore region of the Nicoya Gulf and extending toward the noretheast on the onshore region; and the Parrita basin located offshoreand onshore with a sedimentary fill of more 4.5 km. Both basins are limited on the south by a shallow uplift of the basement which represents an extension of the outer arc over the platform.It is interpreted that in the Cretaceous, the area now occupied by the Nicoya and Patarrita basins, was part of an extense forearc system that spanned along the Pacific margin of Costa Rica encompassing the Tempisque and Terraba basins. The present structural configuration of the Parrita and Nicoya Basins initiates in the Middle Eocene, relatedto shear stresses caused by the rotationin clockwise direction of the southern portion of the Costa Rica territory along a main transcurrent fault zone. Such movement displaced the Tempisque and Terraba basins on the south and north respectively, developing the half-graben configuration and the extense system of strike-slip faults of the transtension and the subsidence along this series of faults, transverse to the coast, which are in some cases, still active.The seismic stratigraphy analysis defines five seismic sequences and a equal number of time structure maps, besides the top of basement. This analysis has been tied up to the surface geology information and discussed under the light of sequence stratigraphy concepts. In general, the sediment in depocenters of this central Pacific region of Costa Rica, can be characterized as a shallowing upward megasequence, including deposits ranging from slope to shallow marine.

Stomach content analyses of the threadfin anglerfish Lophiodes spilurus (Lophiiformes: Lophiidae) associated with deepwater shrimp fisheries from the central Pacific of Costa Rica

Our knowledge of deepwater ecosystems along the Pacific of Central America is extremely limited. We analyzed the diet composition of 200 adult specimens of Lophiodes spilurus ranging in size from 7.8 to 17.8 cm total length (TL). Samples were obtained from deep bottom trawls (depth: 105-238 m) along the central Pacific of Costa Rica. We calculated the percentage of number (% N), weight (% W), and occurrence (% O) of each food item encountered in the stomachs; based on this information, the Index of Relative Importance (IR) was calculated. Moreover, we estimated diet overlap for three different size classes (<10.1, 10.1-15.0 and > 15.1 cm TL). The results revealed exclusively two groups of benthic prey items: crustaceans (30%) and teleost fish (70%) in their diet. The most frequent preys were pandalid shrimps Plesionika trispinus (% O = 17) and the fathom mora Physiculus rastrelliger (% O = 12). The greatest diversity and frequency of abundance of food items was observed in intermediate-sized individuals (10.1-15.0 cm TL). Small-sized L. spilurus (< 10.1 cm TL) fed mainly on teleost fish, while larger (> 15.0 cm TL) preyed on large-sized stomatopods and teleost fish. There was a clear diet overlap between small and intermediate-sized L. spilurus (p < 0.05). However, differences in diet-overlap were not detected in small and large-sized individuals or intermediate and large-sized specimens (p > 0.05). Our results suggest that L. spilurus feeds exclusively on crustaceans (Decapoda and Stomatopoda) and benthic teleost fish along the Pacific of Costa Rica. While small and large-sized individuals showed a more pronounced selectivity for certain prey items, the high diversity of benthic prey items observed in intermediate-sized specimens suggest a more opportunistic foraging behavior.

Variación genética y flujo de genes entre poblaciones de Crocodylus acutus (Crocodylia: Crocodylidae) en tres ríos del Pacífico Central, Costa Rica

The crocodylid Crocodylus acutus is found in the Central Pacific of Costa Rica only in small populations, and the species is protected by law. RAPD was used to analyze 70 DNA samples of Crocodylus acutus from the rivers Jesus Maria, Tarcoles and Tusubres in the Central Pacific of Costa Rica in order to estimate genetic diversity, differentiation among populations, gene flow and genetic distance between them. Genetic diversity was low in the three rivers, H = 0.2201 in the Jesus Maria river, 0.2358 in the Tarcoles river and 0.2589 in the Tusubres river. Among the three populations there is a metapopulational dynamic (GST = 0.0367), mainly between the populations of the Jesus Maria and Tarcoles rivers. The value of gene flow (Nm = 13.1361) and the number of individuals reported for each river in 2004 suggests that the population of the Tarcoles river is the source and those from Jesus Maria and Tusubres are the drains. There was a direct relationship between the genetic distance and the geographical distance (z = 1.1449, r = 0.9731, p < 0.0010). A conservation strategy for these crocodiles must consider the existence of the metapopulation between the three rivers and the importance of studying the genetics of the American Crocodile in the rest of the Pacific coast of Costa Rica, as well as over the entire distribution range of this species.

Revisión taxonómica del grupo Haplothrips-Karnyothrips (Thysanoptera: Phlaeothripidae)

The generic group ("ensemble") Haplothrips-Karnyothrips is reviewed, following the most recently published criteria for distinguishing generic characters. We establish a new diagnosis for each genus. A review of a Central American collection is included and a new genus of Phlaeothripidae is described from the Central Pacific of Costa Rica from specimens collected on Cyperaceae flowers during the dry season. The genus can be distinguished by widely separated maxillary stylets, absent maxillary bridge, pelta shape and the setae B1, which measures two thirds of the tube length. We include a key based on characters of phylogenetic importance.