Gastrotricha is a group of meiofaunal-sized, free-living invertebrates present in all aquatic ecosystems. The phylum includes over 860 species globally, which 505 nominal have been recorded marine sandy sediments; another 355 taxa inhabit the freshwater environments, where they are recurrent members periphyton and epibenthos, and, to lesser degree, plankton interstitial fauna. Gastrotrichs part permanent meiofauna general, rank among top five groups for abundance within meiobenthic...

Rhodoliths are round calcareous red algae that form extensive beds and associated with them a diverse suite of species. Rhodolith among the least known coastal–marine ecosystems, even less is understood about their flora fauna. Here, we present an evaluation biodiversity larger than 500 μm rhodoliths at Isla del Coco National Park, Costa Rica, oceanic island in Eastern Tropical Pacific, km offshore mainland. This research determined influence rhodolith degree aggregation (distance individual...

Spatial-temporal tendencies of marine faunal observations in touristic dives (Isla del Coco, Costa Rica). Data on several species collected over 15 years (1991 to 2007), by dive-masters the diving company Undersea Hunter, at 27 sites around Isla Coco (Cocos Island), Pacific Rica, were analyzed. The goal was create a base line pelagic that live waters Island based reports their activity during tourist dives. A data matrix generated and multivariate methods used determine patterns temporal...

Seagrasses in the eastern Pacific are mainly confined to temperate and subtropical regions of North America, with limited reports presence Central America Chile. We report a unique monospecific meadow Halophila baillonii for Eastern Tropical Golfo Dulce, southern coast Costa Rica. This constitutes first sighting seagrasses from Rica since disappearance only reported seagrass meadow, Ruppia maritima baillonii, 1996. Twenty sediment cores (5 cm diam., 15 deep) were taken at 10 locations...

An extensive collecting effort resulted in identification of 106 species polychaetes from the intertidal and shallow subtidal Isla del Coco, Costa Rica. One hundred three reported here are new records. Only two had not been previously collected Pacific coastline between Mexico Chile. Transport to island either as larvae, adults, or by rafting is discussed. Comparisons made with less well-analyzed polychaete fauna Galapágos Islands, lower richness on smaller ecologically variable Coco....

Geographic Information Systems (GIS) applications used in marine habitats are powerful tools for management and monitoring of reserves resources. Here, we present a series maps the soft hard substrates shallow waters (>80 m depth) Parque Nacional Isla del Coco (PNIC= National Park). We use bathymetry data field as input GIS, GAM, kriging methods to generate that describe bottom characteristics. Eight types were found PNIC by composition grain size. The shore island islets consisted rocky...

The vertical zonation of epifauna and algae on rocky substrates the Gulf Nicoya, Costa Rica. distribution epifaunal algal species was studied at five intertidal shore sites de Nicoya estuary, Pacific coast Each site visited once during low tide, between April July 2004. Two sampling were located each side mouth estuary (Montezuma Punta Agujas), one in middle zone (Caldera), two inner (Cocorocas, Yuca island), latter close to Tempisque river. Sites selected measure variation distri- bution...

This study presents a description of the tropical intertidal shores Cocos Island (Isla del Coco), Pacific, Costa Rica. The zones were surveyed photographically with 116 digital images quadrats (25 x 25 cm), and 130 cliffs in five days. percent cover abundance species estimated by image analysis. Twenty-three taxa found, Mollusca was most specious (12 species). Littorinid neritid mollusks dominant higher littoral area. predator snails Plicopurpura patula pansa, Thais brevidentata, high...

The intertidal rocky shore of Bahia Salinas (seasonal upwelling area), northern Pacific coast Costa Rica, was studied to determine the vertical zonation algae and invertebrates. In two sheltered exposed sites communities were sampled twice, once during (April) again nonupwelling season (October). At each site five strata with 25x25cm quadrats. Each stratum had quadrats digital photographs quadrat taken. Digital image analysis used estimate percent cover sessile species abundance mobile...

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 industrial or agrochemical environmental pollutants that disrupt the endocrine system of reptiles. One group compounds concern is persistent organic (POPs), some which have been detected in Costa Rican Some POPs, such as polychlorinated biphenyls and DDT its metabolites, exhibit estrogenic...

The sipunculan fauna of Isla del Coco was found to be quite diverse with eleven species reported. Several the species, as well echiuran Thalassema steinbecki, have been encountered previously from Pacific Costa Rica. More surprising is occurrence several sipunculans not known eastern region such Siphonosoma cumanense, Phascolosoma scolops, Aspidosiphon gosnoldi, A. misakiensis, and (Paraspidosiphon) laevis. Possible larval sources for those unknown this are discussed. identity specimens...

The present study shows spatial patterns in the faunal assemblage of decaying wood and sediments, with emphasis on polychaetes. survey was executed across a salinity gradient tropical mangrove estuary Costa Rica. To capture organisms we analyzed decomposing logs found Térraba sediment samples were taken corer sand bottom. Seven different phyla samples. Of 192 individuals samples, 18 polychaetes belonging to nine families 11 species. Analyses resulted 2 564 distributed five phyla. Polychaetes...

Several biological and physical factors change the rocky shore communities. The desiccation time tolerance of intertidal species produce vertical zonation. In many studies around world, a temporal in this zonation is presented.In Costa Rica, only that include trends were carried out Punta Mala Montezuma, Pacific coast 80's. Cocos Island National Park, Rica surveyed photographically. Chatham bay was sampled three expeditions (January 2007, October 2007 April 2008). Photos corresponding to...

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, World Heritage Site. Taxonomically significant characters A. (number myotomes, gonads only on right side body, shape metapleural folds) are discussed. These lancelets were living in poorly sorted and slightly gravelly sand. Although this taxon has circumtropical...

<p>Este estudio resume información publicada sobre las especies de invertebrados reportadas para la zona intermareal costa rocosa y playas arena del Pacífico Norte Costa Rica. Además, se presentan datos nuevos riqueza comunidad varias áreas protegidas o no muestreadas durante el año 2012. Los resultados indican una amplia variación en número reportadas, siendo los principales contribuyentes a fauna moluscos, crustáceos poliquetos. El dependió grupo faunístico esfuerzo muestreo estudios...

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 old facilitates identification hidden patterns. From February 1984 to April 1987 (49 sampling dates), core samples (17.7cm2, 15cm deep) were collected at low tide sand-mud flat mid upper Gulf Nicoya estuary, Pacific, Costa Rica. Predator exclusion experiments (cages 0.5 x 0.2m, galvanized wire, mesh size 5mm), conducted site 1985 (dry rainy...

The subtidal benthos of tropical islands has been poorly studied in the Eastern Tropical Pacific. Several studies have published on taxonomic collections from oceanic region, but ecological features and community structure are practically unknown. In present study, composition polychaete along a depth gradient sand bottom Bahía Chatham, Isla del Coco National Park, Costa Rica is analyzed. Fifty species polychaetes belonging to 28 families were found. There peak diversity, abundance richness...