scholarly journals Characterization of deepwater invertebrates at Isla del Coco National Park and Las Gemelas Seamount, Costa Rica

2017 ◽  
pp. 303-319
Author(s):  
Richard M. Starr ◽  
Jorge Cortés ◽  
Cheryl L. Barnes ◽  
Kristen Green ◽  
Odalisca Breedy

The deepwater faunas of oceanic islands and seamounts of the Eastern Tropical Pacific are poorly known. From 11-22 September 2009, we conducted an exploration of the deepwater areas around Isla del Coco National Park and Las Gemelas Seamount, located about 50km southwest of Isla del Coco, Costa Rica using a manned submersible to survey the seafloor habitats. The goal of the exploration was to characterize the habitats and biota, and conduct quantitative surveys of the deepwater portions of Isla del Coco National Park and Las Gemelas. We completed a total of 22 successful submersible dives, spanning more than 80hr underwater, and collected a total of 36hr of video. With respect to invertebrates, our objectives were to gather quantitative information on species composition, density, distribution and habitat associations as well as to compare the invertebrate communities between the two sites. A total of 7172 invertebrates were counted from analysis of the video collected on this project. Larger organisms were counted and placed into 27 taxonomic groups to characterize the deepwater invertebrate fauna of Las Gemelas Seamount and Isla del Coco National Park. The Shannon-Weiner Index for biodiversity (H’) was calculated to be 0.14 ± 0.02 for Isla del Coco and 0.07 ± 0.03 for Las Gemelas surveys. Although richness was fairly equal between the two sites, evenness was greater at Isla del Coco (J = 0.04 ± 0.006) when compared to Las Gemelas (J = 0.02 ± 0.01). This lower level of evenness in the community at Las Gemelas was a result of high densities of a few dominant species groups, specifically sea urchins and black corals. We also evaluated invertebrate percent cover at both Isla del Coco and Las Gemelas Seamount with respect to habitat type, slope and rugosity. Results indicated that highly rugose habitats contained the highest frequencies of all invertebrates at both sites, with the exception of glass sponges and polychaetes at Isla del Coco, which were found in greater quantities at intermediate levels of rugosity. Information obtained from these submersible surveys indicate that seamounts in the tropical eastern Pacific Ocean may be an important source of biodiversity and that more quantitative surveys are needed to characterize the fauna of the region. Citation: Starr, R.M., J. Cortés, C.L. Barnes, K. Green & O. Breedy. 2012. Characterization of deepwater invertebrates at Isla del Coco National Park and Las Gemelas Seamounts, Costa Rica. Rev. Biol. Trop. 60 (Suppl. 3): 303-319. Epub 2012 Dec 01.

2017 ◽  
pp. 347-362
Author(s):  
Richard M. Starr ◽  
Kristen Green ◽  
Enric Sala

The deepwater faunas of oceanic islands and seamounts of the Eastern Tropical Pacific are poorly known. From 11-22 September 2009 we conducted an exploration of the deepwater areas of the Isla del Coco Marine Conservation Area, Costa Rica and a nearby seamount using a manned submersible. The goal of the exploration was to characterize the habitats and biota, and conduct quantitative surveys of the deepwater portions of Isla del Coco National Park and Las Gemelas Seamount, located about 50km southwest of Isla del Coco. We completed a total of 22 submersible dives, spanning more than 80hr underwater, and collected a total of 36hr of video. We surveyed habitats from 50-402m and observed more than 45 species of fishes, some of which have not yet been described and are likely new to science. The diversity of fish species in deep water at Isla del Coco National Park was lower than the diversity of fishes in shallow water, and eight species groups accounted for more than 95% of the total fish biomass. The combined density of all fish species was higher at Las Gemelas Seamount (253 fishes/100m2) than at Isla del Coco National Park (138 fishes/100m2). The combined density of fishes in habitats comprised primarily of bedrock or large boulders outcrops was more than three times as high at Las Gemelas Seamount as it was at Isla del Coco National Park. This discrepancy was caused by the extremely high concentration of Anthiinae fishes in rocky habitats at Las Gemelas Seamount. Densities of fishes in the other habitats were similar between the two sites. Similarly, when estimates of fish density were plotted by slope categories the density was much greater on steep slopes, which were usually comprised of rock habitats. Also, the density of fishes was greatest on high rugosity habitats. Results of these submersible surveys indicate that seamounts in the tropical eastern Pacific Ocean may be an important source of biodiversity and that more quantitative surveys are needed to characterize the fauna of the region. Citation: Starr, R.M., K. Green & E. Sala. 2012. Deepwater fish assemblages at Coco Island National Park and Las Gemelas Seamounts, Costa Rica. Rev. Biol. Trop. 60 (Suppl. 3): 347-362. Epub 2012 Dec 01.


Check List ◽  
2014 ◽  
Vol 10 (6) ◽  
pp. 1401 ◽  
Author(s):  
Atsunobu Murase ◽  
Arturo Angulo ◽  
Yusuke Miyazaki ◽  
William Bussing ◽  
Myrna López

A checklist of the marine and estuarine fishes of the inner part of the Gulf of Nicoya, Pacific coast of Costa Rica, Central America, was compiled by examining a museum fish collection, resulting in 72 families and 274 species. Of these species, 127 (46.4%) were marine species and 147 (53.6%) were estuarine-associated species. In terms of their life history and considering the habitat type classification, 188 (almost 70% of the total) were categorized as species inhabiting soft-bottom habitats, reflecting the large estuarine environment and rich fish diversity of the Gulf despite its relatively small area in the tropical Eastern Pacific region. Furthermore, the list contains 13 threatened species of IUCN Red List, which need further research to understand their abundance and their exposure to habitat loss in the Gulf. Further detailed studies on its fish fauna and habitat are needed to better understand and conserve biodiversity within the whole Gulf.


2017 ◽  
pp. 275-278
Author(s):  
Andrés López-Garro ◽  
Ilena Zanella ◽  
Geiner Golfín-Duarte ◽  
Maikel Pérez-Montero

The blacktip reef shark Carcharhinus melanopterus, is one of the most common Indo-Pacific reef sharks. On April 29, 2012, a juvenile male blacktip reef shark measuring 89 cm total length (TL), was incidentally caught during a research expedition in Chatham Bay, Isla del Coco National Park, Costa Rica, located in the Tropical Eastern Pacific. This is the first record of the species from Isla del Coco National Park, Costa Rica, and from the Tropical Eastern Pacific. Citation: López-Garro, A., I. Zanella, G. Golfín-Duarte & M. Pérez-Montero. 2012. First record of the blacktip reef shark Carcharhinus melanopterus (Carcharhiniformes: Carcharhinidae) from the Eastern Tropical Pacific. Rev. Biol. Trop. 60 (Suppl. 3): 275-278. Epub 2012 Dec 01.


2016 ◽  
Vol 8 (1) ◽  
pp. 99-101
Author(s):  
Sergio A Villegas-Retana ◽  
Adriana Picado-Rossi ◽  
Alejandro Durán-Apuy

The common house gecko, Hemidactylus frenatus, is a native of Indonesia that has rapidly colonized new environments. Normally it is found in human constructions, but it can also invade natural environments and is causing the displacement and extinction of some native lizards, mostly in oceanic islands. In the Pacific reserve of Isla del Coco (Costa Rica) we captured nine specimens with sticky traps and direct capture. Theridium spp. accounted for 54% of its stomach contents (25,7% were unidentified remains and 18,8% Hymenoptera).


2020 ◽  
Vol 5 (1) ◽  
pp. 125-137
Author(s):  
Ennie Chahyadi ◽  
Mayta Novaliza Isda ◽  
Appriliya Destiyana ◽  
Fitmawati Fitmawati ◽  
Desita Salbiah

Bukit Tiga Puluh National park (TNBT) of Riau Province is a nature conservation area with a high diversity of fauna, one of which is the butterfly. Butterfly species diversity is influenced by the vegetation in their habitat. The TNBT utilization zone has a habitat type with varied vegetation. There is no information about the species of butterflies in the area. This study aimed to identify morphological character of butterflies and vegetation based on morphological characters. The method used was exploration. The catching area of the butterfly was the Granite waterfall and the Bukit Lancang path of TNBT utilization zone. Samples made as insectarium and herbarium. The  identification of butterfly characters consisted of the head, thorax, abdomen, legs and wings. There were a number of different types of butterflies and plants between the Granite waterfall area (22 and 28 species) and the Bukit Lancang paths (5 and 9 species). The type of butterfly was dominated by the family Nymphalidae. This is due to the amount of vegetation and environmental conditions that are more favorable in the granite waterfall area. The key determinants of butterfly species are the characters of the wing. The results of this study can contribute to maintaining the TNBT butterflies in Riau Province and also as database information of butterflies species in Indonesia.


2021 ◽  
pp. 46-54
Author(s):  
Daniel Ramirez-Arce

The Fer-de-lance or terciopelo (Bothrops asper) inhabits a wide range of environmental conditions and habitats across Central America. While much information on the species is based on anecdotal observations and useum specimens, data collected under natural conditions are more limited. To better document its natural history, this study sought to determine the habitat use and age structure of B. asper in the Quebrada Gonzalez sector of Braulio Carrillo National Park, Costa Rica. Snake surveys were conducted from January 2015 to August 2017 and used to evaluate the population age-class distribution and sex ratio. To evaluate macrohabitat use, surveys were conducted in four habitat types (mature forest, late succession, early succession, and human infrastructure). Microhabitat use was determined by recording several structural variables at each snake location and at random sites. Amphibians were sampled in each habitat type to evaluate the available prey base. Fifty-five individuals were captured, mostly females and juveniles, with five recaptures. Snakes were encountered in all habitat types but most often in early succession forests, which have dense vegetation cover and high prey availability. Snakes selected areas with heavy understory cover when resting, and more exposed sites, often closer to bodies of water, when ambushing prey or moving. Human-disturbed sites were used least. Although snake encounters did tend to correlate with higher amphibian abundance, other factors such as mammalian prey abundance could also influence snake distribution.


2017 ◽  
pp. 303-319
Author(s):  
Jeffrey A. Sibaja-Cordero ◽  
Jorge Cortés ◽  
Harlan K. Dean

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 gradient from the sand bottom of Bahía Chatham, Isla del Coco National Park, Costa Rica is analyzed. Fifty species of polychaetes belonging to 28 families were found. There is a peak in diversity, abundance and richness at 28-30m. The lowest values occurred at 50m depth with values increasing below this depth. The composition of species changed with depth with some species being found only at depths either less than or greater than 50m. This pattern can be explained in part by the location of the thermocline that occurred at around 50m depth. Citation: Sibaja-Cordero, J.A., J. Cortés & H.K. Dean. 2012. Depth diversity profile of polychates worms in Bahía Chatham, Isla del Coco National Park, Pacific of Costa Rica. Rev. Biol. Trop. 60 (Suppl. 3): 293-301. Epub 2012 Dec 01.


Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.


Author(s):  
A. Carlsson ◽  
J.-O. Malm ◽  
A. Gustafsson

In this study a quantum well/quantum wire (QW/QWR) structure grown on a grating of V-grooves has been characterized by a technique related to chemical lattice imaging. This technique makes it possible to extract quantitative information from high resolution images.The QW/QWR structure was grown on a GaAs substrate patterned with a grating of V-grooves. The growth rate was approximately three monolayers per second without growth interruption at the interfaces. On this substrate a barrier of nominally Al0.35 Ga0.65 As was deposited to a thickness of approximately 300 nm using metalorganic vapour phase epitaxy . On top of the Al0.35Ga0.65As barrier a 3.5 nm GaAs quantum well was deposited and to conclude the structure an additional approximate 300 nm Al0.35Ga0.65 As was deposited. The GaAs QW deposited in this manner turns out to be significantly thicker at the bottom of the grooves giving a QWR running along the grooves. During the growth of the barriers an approximately 30 nm wide Ga-rich region is formed at the bottom of the grooves giving a Ga-rich stripe extending from the bottom of each groove to the surface.


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