Jeffrey A Sibaja-Cordero

• Professor
• Professor (Full) at University of Costa Rica

Introduction: Seasonal upwelling is a displacement offshore of surface seawater and replacement by cool deeper water with higher nutrient levels by the influence of the wind. On the north Pacific coast of Costa Rica the upwelling is present from December to April. Objective: Within this seasonal upwelling area, Salinas Bay was sampled to determine...

Introduction: Litter decomposition in mangrove forest is a process in which organic matter produced as leaves in the trees is later transferred to the sediment. Several invertebrates participate in the fragmentation of leaves, and they might have a great impact in the later stages of decomposition of mangrove leaves. Objective: The study aims to ch...

Increased human activities on sandy beaches have significantly impacted ecosystems. This study aims to determine whether beaches with higher tourism and human activities exhibit greater impact on various ecological indicators compared to less-visited beaches. Ecological monitoring was performed across three sandy beaches, where sand samples were co...

Introduction: Annelid polychaete worms of the family Sabellariidae build reefs by cementing together sand grains. These reefs increase local habitat heterogeneity and species diversity. The reefs are used as a refuge by invertebrates, and crustaceans are frequent. Objective: To list the species of crustaceans found in Phragmatopoma sp. reefs on two...

The ecology of macrofauna on the sandy bottom of oceanic islands in the tropics has rarely been studied. The present study was conducted at Isla del Coco, Costa Rica, a tropical oceanic island, to determine how the soft-bottom macrofauna assemblages vary along different levels of ocean exposure and their associated environmental conditions. The mac...

Introduction: Annelid polychaete worms of the family Sabellariidae build reefs by cementing together sand grains. These reefs increase local habitat heterogeneity and species diversity. The reefs are used as a refuge by invertebrates, and crustaceans are frequent. Objective: To list the species of crustaceans found in Phragmatopoma sp. reefs on two...

Rhodoliths are round calcareous red algae that form extensive beds and associated with them are a diverse suite of species. Rhodolith beds are among the least known coastal–marine ecosystems, and even less is understood about their associated flora and fauna. Here, we present an evaluation of the biodiversity larger than 500 μm associated with rhod...

This study was a baseline with quantitative data of marine litter along the Gulf of Nicoya, Costa Rica. The objective of the study was to quantify marine litter and its association with human activities in this estuarine gulf. A total of fourteen sandy beaches were cataloged by the degree of urbanization, tourism intensity, beach cleaning programs,...

Anelasma squalicola is a parasitic barnacle of members of the deep-water shark families Etmopteridae, Pentanchidae and Scyliorhinidae. We report the first published confirmation of this species in the Eastern Pacific Ocean, based on material collected off Costa Rica, its first record as a parasite of the Ninja lantern shark, Etmopterus benchley (Et...

Los cirripedios se conocen a nivel mundial como balanos y percebes. Viven adheridos a sustratos duros, conchas, caparazones de organismos, incluso a otros crustáceos y cetáceos. Su nombre tiene origen en la posesión de una serie de cirros en sus patas, mismos que les facilitan realizar diversas actividades, como la natación, alimentación, reproducc...

The cryptofauna are the small cryptic organisms that inhabit the interstices of coral colonies and have a great contribution to the biodiversity of the reef. Some of these species are vulnerable to environmental deterioration due to their dependency on living coral. In the 1990s, Culebra Bay, located in the North Pacific of Costa Rica, was consider...

Introduction: The latitudinal diversity gradient (LDG), a fundamental ecology pattern for higher organisms, has explained the increase of species diversity from the poles towards the tropics. Can we explain the biodiversity of Papillomaviruses based on this pattern? Objective: To analyse the phylogenetic diversity and phylogeography of most known...

Gastrotricha is a group of meiofaunal-sized, free-living invertebrates present in all aquatic ecosystems. The phylum includes over 860 species globally, of which 505 nominal species have been recorded in marine sandy sediments; another 355 taxa inhabit the freshwater environments, where they are recurrent members of the periphyton and epibenthos, a...

Las áreas marinas protegidas se han establecido con la expectativa de beneficiar las poblaciones de organismos para mejorar su resiliencia y asegurar sus beneficios ecológicos. En ambientes costeros, la zona rocosa entre mareas tiene poblaciones de gasterópodos de interés humano. Por lo tanto, debe estudiarse si el establecimiento de zonas de prote...

El acceso a datos actualizados, sobre los nombres y distribución de las especies de crustáceos presentes en un área en particular, es un primer paso para evaluar cambios debidos a factores locales, regionales o globales, como la sobrepesca, la contaminación y el cambio climático. Los datos en este estudio están basados en las expediciones de los bu...

Clumps of the gooseneck barnacle Pollicipes elegans were found in the central Pacific on a rocky shore of Costa Rica. This species is known to be abundant in northern and southern latitudes of the eastern tropical Pacific. This study describes aspects of its demography and size structure, as well as habitat features in Costa Rica. The clumps were g...

Surveillance influence in a rocky shore within a marine protected area, Central Pacific of Costa Rica. Rocky intertidal are important sites for fish, birds, invertebrates and algae, among others, which are used for the extraction of food resources for coastal communities. We present the results of conservation assessment of a rocky shore in the Cen...

Surveillance influence in a rocky shore within a marine protected area, Central Pacific of Costa Rica. Rocky intertidal are important sites for fish, birds, invertebrates and algae, among others, which are used for the extraction of food resources for coastal communities. We present the results of conservation assessment of a rocky shore in the Cen...

Rocky intertidal are important sites for fish, birds, invertebrates and algae, among others, which are used for the extraction of food resources for coastal communities. 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 ind...

Data set of Spatial distribution of count data of sandy beach macrofauna Caribbean Coast, Costa Rica. The data is in format .cvs for analysis in R. Methodology: The data are 29 sediment samples and these were collected (September 2006) each 200m in a parallel transect on the low spring tide level in a sandy beach of the Caribbean coast of Costa Ric...

Sequence of commands for spatial distribution of count data (Negative Binomial Distribution). Aggregated distribution of individuals of Scolelepis squamata in a sandy beach on the Caribbean, Costa Rica.

Sequence of commands for spatial distribution of count data (Poisson Distribution). Random distribution of isopod individuals in a sandy beach on the Caribbean, Costa Rica

The coral reef at Cahuita National Park in the Caribbean coast of Costa Rica represents very diverse marine ecosystem. Most of this diversity knowledge has been the result of benthic surveys, while very little is known from pelagic studies. A zooplankton survey sampling was conducted monthly from September 2010 to August 2011, finding new records o...

Spatial and temporal structure of the ichthyofauna of the Estuary of Tamarindo, Las Baulas National Marine Park, Costa Rica. Fish communities in mangrove areas have an ecological and socio-economic importance. The management in this kind of habitat is based on the data information about spatial and temporal patterns. The main goal of the study is d...

Knowing the spatial pattern and densities of individuals in a population is basic to understand ecology such as their response to environmental gradients. The main goal of the present study is to describe the abundances and distribution of the benthic fauna in the lower intertidal level of a sandy beach at Pacuare Reserve, Caribbean Coast, Costa Ri...

The availability of baseline data on water parameters and primary productivity is essential in comparative studies aimed at identifying environmental trends, like eutrophication, in coastal embayments. In this context, the objetive of this work is to make accessible data, collected from 2000 to 2002, on 13 water parameters (Secchi depth, temperatur...

Seasonal changes in rainfall might have an impact on the decomposition of mangrove leaf litter. This study analyzed the influence of weather conditions (season) on the decay rate, nitrogen, and phosphorus content as a decomposition indicator of leaf litter of Rhizophora racemosa. These measurements were taken at two sites in the Térraba-Sierpe Nati...

The eastern tropical Pacific (ETP) is an isolated oceanic region exposed to extreme oceanographic conditions, including low salinity, low pH, high temperatures during El Niño, and low temperatures during La Niña and seasonal upwelling. The coral reefs in this region have a relatively limited suite of species compared to other coral reef areas of th...

Reports on the abundances and on metal concentrations in intertidal estuarine invertebrates from the Eastern Tropical Pacific are rare. Thus, the objectives of this report are to make accessible data on the abundances (1984-1987, 49 dates; 2013, 12 dates) of sipunculans, brachiopods and hemichordates from a sand-mud flat; and on trace metals (1996,...

Free download: http://authors.elsevier.com/a/1TW9A4wy0KTFgJ The marine macrofauna of the shallow sandy bottom of Isla del Coco, Costa Rica (5°32′N-87°04′W) was assessed in April 2010. Comparisons of richness, density and diversity between levels of exposure to ocean influence were carried out. During this study 15,407 specimens with a mean density...

Las playas rocosas y arenosas son afectadas por diversos factores antropogénicos, que pueden tener una influencia sobre la biodiversidad, aún dentro de las áreas protegidas por el SINAC (Quesada-Alpízar 2005). Esto puede darse por intromisión o exceso de pesca de organismos clave en regular dichos ambientes; una sobrecarga de la visitación turístic...

Las playas rocosas y arenosas son afectadas por diversos factores antropogénicos, que pueden tener una influencia sobre la biodiversidad, aún dentro de las áreas protegidas por el SINAC (Quesada-Alpízar 2005). Esto puede darse por intromisión o exceso de pesca de organismos clave en regular dichos ambientes; una sobrecarga de la visitación turístic...

The objectives of this report are to provide an updated list of the annelid polychaete worm species found at a tropical estuarine intertidal flat, describe long term oscillations of 11 of the species, and the impact of red tides as evidenced by PCA.From 1984 to 1987 (49 dates) 14 sediment cores (17.7 cm2- 15 cm deep) were collected per date at low...

Invertebrate species richness in sandy beaches and rocky coast of Costa Rican North Pacific. This study summarizes published information on the number of invertebrate species reported for the intertidal zone of rocky coasts and sandy beaches of the North Pacific of Costa Rica. In addition, we present new data on macrofaunal species richness for sev...

The intertidal rocky shore of Bahía Panama, within Bahía Culebra in the North Pacific coast of Costa Rica, was sampled to study the biodiversity and the spatial patterns (three sites with differences in wave exposure, and five strata, from low to high tide levels) and temporal variation (a single date in 2007 and 2013) in different microhabitats (o...

Benthic macrofauna found in Sandy beaches from Osa Conservation Area, Puntarenas, Southern Pacific coast of Costa Rica. The diversity and species composition of the intertidal sandy beaches in the southern Pacific coast of Costa Rica were studied by means of cores collected along perpendicular transects to the beaches. The numbers of strictly marin...

The present study shows spatial patterns in the faunal assemblage of decaying wood and sediments, with emphasis on the polychaetes. The survey was executed across a salinity gradient in a tropical mangrove estuary of Costa Rica. To capture the organisms we analyzed decomposing logs found in the Térraba mangrove and sediment samples were taken with...

The diversity and species composition of the intertidal sandy beaches in the southern Pacific coast of Costa Rica were studied by means of cores collected along perpendicular transects to the beaches. The numbers of strictly marine species varied between 5 to 13 taxa, representing an intermediate value compared to those previously reported for thes...

Seagrasses in the eastern Pacific are mainly confined to temperate and subtropical regions of North America, with limited reports of presence in Central America and Chile. We report a unique monospecific meadow of Halophila baillonii for the Eastern Tropical Pacific in Golfo Dulce, southern Pacific coast of Costa Rica. This report constitutes the f...

Subtidal sediments of Isla del Coco (Cocos Island), Costa Rica were described in their grain size, sorting, organic matter, and carbonates from 27 dredge samples (3–75 m), collected in April 2010. The organic matter range between 1.37–3.31% and carbonates presented a mean of 74±17%. The sorting was moderately or poorly. The grain size ranged betwee...

Samples from the scarcely-studied sedimentary seabed from the Isla del Coco (Costa Rica) yielded a single species of Tanaidacea, belonging to a new genus of Leptocheliidae, Cocotanais. The new genus shows affinities with Pseudonototanais and Heterotanais in bearing a conspicuous forcipate cheliped in the males, which in Cocotanais has a modified me...

During an expedition aimed to study the benthos of subtidal sand bottoms (3-75 m) of Isla del Coco National Park, on the Pacific Ocean side of Costa Rica, a total of 40 species of mollusks were collected and identified. The gastropods were the most diverse with 21 species, followed by the bivalves with 16 species. Also, one species of Polyplacophor...

The availability of data sets for time periods of more than a year is scarce for tropical environments. Advances in hardware and software speed-up the re-analysis of old data sets and facilitates the description of population oscillations. Using recent taxonomic literature and software we have updated and re-analized the information on crustacean d...

The subtidal benthos of tropical islands has been poorly studied in the Eastern Tropical Pacific. Several studies have been published on taxonomic collections from oceanic islands in the region, but ecological features and community structure are practically unknown. In the present study, composition of the polychaete community along a depth gradie...

The lancelet Asymmetron lucayanum complex was collected from subtidal (5-42 m) sandy bottom during a benthic survey designed to describe the biota of Cocos Island National Park (Parque Nacional Isla del Coco), Costa Rica, a World Heritage Site. Taxonomically significant characters of A. lucayanum (number of myotomes, gonads only on the right side o...

Geographic Information Systems (GIS) applications used in marine habitats are powerful tools for management and monitoring of marine reserves and resources. Here, we present a series of maps of the soft and hard substrates in the shallow waters (>80 m depth) of Parque Nacional Isla del Coco (PNIC= Isla del Coco National Park). We use bathymetry dat...

Due to limited seagrass presence, seagrass studies in the eastern Pacific have been scarce. There are only 2 seagrass species reported for the Pacific coast of Costa Rica (Ruppia maritima and Halophila baillonii). The present study is the first in 15 years which examines the presence of a seagrass meadow in the Pacific coast of Costa Rica, the firs...

An extensive collecting effort resulted in identification of 106 species of polychaetes from the intertidal and shallow subtidal of Isla del Coco, Costa Rica. One hundred and three of the species reported here are new records. Only two species had not been previously collected from the Pacific coastline between Mexico and Chile. Transport of polych...

The availability of data sets covering more than a year is scarce for tropical environments. Advances in hardware and software speed-up the re-analysis of old data sets and facilitates the identification of hidden data patterns. From February 1984 to April 1987 (49 sampling dates), core samples (17.7cm2, 15cm deep) were collected at low tide at a s...

El proyecto “Interacción océano-atmósfera y la biodiversidad marina del Parque Nacional Isla del Coco, Costa Rica” es financiado por el Consejo Nacional de Rectores (CONARE). Del 30 de junio al 10 de julio del 2011, un grupo de científicos del Centro de Investigación en Ciencias del Mar y Limnología (CIMAR) de la Universidad de Costa Rica, y del Ce...

A photographically sampling was conducted at Islas Cies, NW, Spain with the goal of determinate the upper and lower limits of vertical distribution of sessile organisms on the intertidal rocky shore of this National Park. The response of the species to different Atlantic Ocean exposure was tested at west coast (exposed) and east coast (sheltered) o...

Several biological and physical factors change the rocky shore communities. The desiccation time and the tolerance of the intertidal species produce the vertical zonation. In many studies around the world, a temporal change in this zonation is presented.In Costa Rica, only studies that include temporal trends were carried out in Punta Mala and Mont...

The sipunculan fauna of Isla del Coco was found to be quite diverse with eleven species reported. Several of the sipunculan species, as well as the echiuran Thalassema steinbecki, have been encountered previously from Pacific Costa Rica. More surprising is the occurrence of several species of sipunculans not previously known from the eastern Pacifi...

The sipunculan fauna of Isla del Coco was found to be quite diverse with eleven species reported. Several of the sipunculan species, as well as the echiuran Thalassema steinbecki, have been encountered previously from Pacific Costa Rica. More surprising is the occurrence of several species of sipunculans not previously known from the eastern Pacifi...

La zona entre mareas rocoso de las bahías Chatham y Wafer en la Isla del Coco, Costa Rica fueron muestreadas fotográficamente con cuadrículas de 25x25cm en enero y octubre de 2007. Bahía Chatham también se visitó en abril 2008. El intermareal de Chatham estaba constituido por roca basáltica y en Wafer por basalto y cantos rodados de ignimbrita. Las...

The phoronid Phoronopsis albomaculata was collected in subtidal (28– 35 m) sandy sediments in Bahía Chatham during a benthic survey designed to describe the biota of Cocos Island (Isla del Coco), Costa Rica, a national park and Human Heritage Site. Occurrence of this widespread species in Cocos Island is the first report of a phoronid for Costa Ric...

Las Perlas Archipelago (LPA) is located off the Pacific Coast of Panama and was designated as a marine protected area (MPA) in 2007. This baseline study of the shallow and deeper sedimentary habitats of the islands partly informed the MPA designation. Ninety-two grab stations and twenty trawl stations were sampled. Sediment grab sample results were...

Olive ridley sea turtles (Lepidochelys olivacea) distribute widely throughout Eastern Pacific (EP) waters. During reproduction these animals aggregate near coastal waters where they may be exposed to indus-trial or agrochemical environmental pollutants that may disrupt the endocrine system of these reptiles. One group of compounds of concern is the...

Spatial-temporal tendencies of marine faunal observations in touristic dives (Isla del Coco, Costa Rica). Data on several marine species collected over 15 years (1991 to 2007), by dive-masters of the diving company Undersea Hunter, at 27 sites around Isla del Coco (Cocos Island), Pacific Costa Rica, were analyzed. The goal was to create a base line...

Spatial-temporal tendencies of marine faunal observations in touristic dives (Isla del Coco, Costa Rica). Data on several marine species collected over 15 years (1991 to 2007), by dive-masters of the diving company Undersea Hunter, at 27 sites around Isla del Coco (Cocos Island), Pacific Costa Rica, were analyzed. The goal was to create a base line...

This study presents a description of the tropical intertidal shores of Cocos Island (Isla del Coco), Pacific, Costa Rica. The intertidal zones were surveyed photographically with 116 digital images of quadrats (25 x 25 cm), and 130 of the cliffs in five days. The percent of cover and abundance of species in the intertidal zones were estimated by di...

The intertidal rocky shore of Bahía Salinas (seasonal upwelling area), northern Pacific coast of Costa Rica, was studied to determine the vertical zonation of algae and invertebrates. In two sheltered and two exposed sites the communities were sampled twice, once during the upwelling (April) and again during the non-upwelling season (October). At e...

The vertical distribution of epifaunal and algal species was studied at five intertidal rocky shore sites on the Gulf de Nicoya estuary, Pacific coast of Costa Rica. Each site was visited once during low tide, between April and July 2004. Two sampling sites were located on each side of the mouth of the estuary (Montezuma and Punta Agujas), one in t...

The vertical zonation of epifauna and algae on rocky substrates of the Gulf of Nicoya, Costa Rica. The vertical distribution of epifaunal and algal species was studied at five intertidal rocky shore sites on the Gulf de Nicoya estuary, Pacific coast of Costa Rica. Each site was visited once during low tide, between April and July 2004. Two sampling...