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The present study analyzed the diet composition, ontogenetic shifts and dietary overlap of Brotula clarkae in relation to stage of maturity and sex. Samples were collected from the trawling fishery along the Pacific coast of Costa Rica (2011-2012) at depths ranging from 41.4 to 168.3 m; however, over 80% of the sampled fish were obtained at depths between 50 and 75 m. Size ranged from 14.4 to 98.4 cm total length. Of the 323 analyzed stomachs, 44.3% were from males, 86% were from immature individuals, and 49.8% had at least one prey item. According to the prey-specific index of relative importance ( PSIRI), decapod shrimps were the most important prey (57.6% PSIRI i) followed by teleosts (28.2% PSIRI i), stomatopods (10.8% PSIRI i), and crabs (3.3% PSIRI i). Male and female B. clarkae exhibited a high dietary overlap ( C H = 0.94). Immature B. clarkae consumed primarily shrimps and crabs (71.5% of stomachs from immature specimens contained shrimps, which accounted for over 66.0% PSIRI i); mature individuals consumed a large proportion of teleosts and stomatopods, which together contributed to over 91.0% PSIRI i. Both immature and mature B. clarkae overlapped spatially with the commercial trawling fishery grounds along the Pacific coast of Costa Rica. However, juveniles feed predominantly on shrimps, suggesting that immature B. clarkae may be subjected to high fishing pressure as by-catch, making them particularly vulnerable to overexploitation. [ABSTRACT FROM AUTHOR]

The diet and diel feeding behaviour of the banded guitarfish Zapteryx xyster were examined along the Pacific coast of Costa Rica. A sample of 235 stomachs was collected between March 2010 and December 2011 as part of an ongoing shrimp-trawl by-catch monitoring programme. Samples from multiple day and night periods allowed testing the hypothesis that Z. xyster is more active at night, thus increasing the amount of food intake during night-time. Overall, shrimps (52·3% prey-specific index of relative importance, PSIRI i) and teleosts (27·2% PSIRI i) were the most important prey categories. Juveniles fed primarily on smaller shrimps ( Solenocera spp.), while adults shifted to larger prey. The amount of food consumed (as % of bodymass) by juvenile and adult Z. xyster increased significantly between 0400 and 1200 hours, while the proportion of empty stomachs decreased during the same time interval. These findings contradict the hypothesis that Z. xyster is more active and feeds at night. The study also revealed that Z. xyster, particularly juveniles, forage on several shrimp species and overlap spatially with the Costa Rican bottom-trawl fisheries. This has important management and conservation implications as Z. xyster may be experiencing high by-catch rates, and because of their life history is presumed to be vulnerable to intense levels of exploitation. [ABSTRACT FROM AUTHOR]

Stomachs from 511 Raja velezi and 340 Mustelus henlei captured as by-catch in the commercial trawling fishery (2010-2012) were analysed to examine diet composition, ontogenetic shifts and degree of dietary overlap between species life stages in the Pacific Ocean of Costa Rica. Shrimps were the most important prey categories in the diet of R. velezi, while teleosts and cephalopods dominated the diet of M. henlei. Diet comparisons between different stages of R. velezi and M. henlei revealed clear ontogenetic dietary shifts: crustaceans (mainly shrimps, crabs and stomatopods) dominated the diet of immature individuals, and adults had a higher proportion of teleosts. The results suggest that R. velezi is an epibenthic predator that specializes in shrimps during early life stages, and to a lesser extent, teleosts as it matures, while M. henlei is an opportunistic predator with a highly diverse diet consisting of teleosts, cephalopods, shrimps and stomatopods. This study also found little evidence of dietary overlap between species or life stages and suggests that intra- and interspecific competition between R. velezi and M. henlei may be reduced by: (1) diet specialization in immature stages of R. velezi, (2) ontogenetic dietary shifts between immature and mature individuals, (3) prey-size selectivity in larger individuals of R. velezi and (4) differences in depth utilization in overlapping geographical regions. [ABSTRACT FROM AUTHOR]

Abstract: Haplotype data were obtained from a sample of 100 unrelated male individuals from Costa Rica, for 12 Y-chromosome STRs. A total of 86 different haplotypes were identified, of which 76 were unique and the most frequent haplotype was found in 4 individuals. High haplotype diversity was found (99.6%), being DYS385, representing two loci, the most diverse marker, and DYS393 presented the lowest gene diversity value. Genetic distances were calculated between our results and previously published haplotype data for the same set of Y-STRs. [Copyright &y& Elsevier]

Abstract: Allele frequencies for 18 STR autosomal loci (D3S1358, VWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820, D16S539, TH01, TPOX, CSF1PO, Penta D, Penta E, D19S433, D2S1338 and SE33) were obtained from a sample of 191–500 unrelated individuals from Costa Rica, Central America. [Copyright &y& Elsevier]

Abstract: Allele frequencies for 11 STR autosomal loci (F13A01, F13B, FESFPS, LPL, CSF1PO, TH01, TPOX, VWA, D16S539, D7S820 and D13S317) were obtained from a sample of 200 unrelated individuals from Costa Rica, Central America. [Copyright &y& Elsevier]

No-take marine protected areas (MPAs) can mitigate the effects of overfishing, climate change and habitat degradation, which are leading causes of an unprecedented global biodiversity crisis. However, assessing the effectiveness of MPAs, especially in remote oceanic islands, can be logistically challenging and often restricted to relatively shallow and accessible environments. Here, we used a long-term dataset (2010-2019) collected by the DeepSee submersible of the Undersea Hunter Group that operates in Isla del Coco National Park, Costa Rica, to (1) determine the frequency of occurrence of elasmobranch species at two depth intervals (50-100 m; 300-400 m), and (2) investigate temporal trends in the occurrence of common elasmobranch species between 2010 and 2019, as well as potential drivers of the observed changes. Overall, we observed 17 elasmobranch species, 15 of which were recorded on shallow dives (50-100 m) and 11 on deep dives (300-400 m). We found a decreasing trend in the probability of occurrence of Carcharhinus falciformis over time (2010-2019), while other species (e.g. Taeniurops meyeni, Sphyrna lewini, Carcharhinus galapagensis, Triaenodon obesus, and Galeocerdo cuvier) showed an increasing trend. Our study suggests that some species like S. lewini may be shifting their distributions towards deeper waters in response to ocean warming but may also be sensitive to low oxygen levels at greater depths. These findings highlight the need for regional 3D environmental information and long-term deepwater surveys to understand the extent of shark and ray population declines in the ETP and other regions, as most fishery-independent surveys from data-poor countries have been limited to relatively shallow waters., (© 2024. The Author(s).)

Understanding the link between seamounts and large pelagic species (LPS) may provide important insights for the conservation of these species in open water ecosystems. The seamounts along the Cocos Ridge in the Eastern Tropical Pacific (ETP) ocean are thought to be ecologically important aggregation sites for LPS when moving between Cocos Island (Costa Rica) and Galapagos Islands (Ecuador). However, to date, research efforts to quantify the abundance and distribution patterns of LPS beyond the borders of these two oceanic Marine Protected Areas (MPAs) have been limited. This study used drifting-pelagic baited remote underwater video stations (BRUVS) to investigate the distribution and relative abundance of LPS at Cocos Ridge seamounts. Our drifting-pelagic BRUVS recorded a total of 21 species including elasmobranchs, small and large teleosts, dolphins and one sea turtle; of which four species are currently threatened. Depth of seamount summit was the most significant driver for LPS richness and abundance which were significantly higher at shallow seamounts (< 400 m) compared to deeper ones (> 400m). Distance to nearest MPA was also a significant predictor for LPS abundance, which increased at increasing distances from the nearest MPA. Our results suggest that the Cocos Ridge seamounts, specifically Paramount and West Cocos which had the highest LPS richness and abundance, are important aggregation sites for LPS in the ETP. However, further research is still needed to demonstrate a positive association between LPS and Cocos Ridge seamounts. Our findings showed that drifting pelagic BRUVS are an effective tool to survey LPS in fully pelagic ecosystems of the ETP. This study represents the first step towards the standardization of this technique throughout the region., Competing Interests: The authors have declared that no competing interests exist.

Reef fish assemblages are exposed to a wide range of anthropogenic threats as well as chronic natural disturbances. In upwelling regions, for example, there is a seasonal influx of cool nutrient-rich waters that may shape the structure and composition of reef fish assemblages. Given that climate change may disrupt the natural oceanographic processes by altering the frequency and strength of natural disturbances, understanding how fish assemblages respond to upwelling events is essential to effectively manage reef ecosystems under changing ocean conditions. This study used the baited remote underwater video stations (BRUVS) and the traditional underwater visual census (UVC) to investigate the spatiotemporal patterns of reef fish assemblages in an upwelling region in the North Pacific of Costa Rica. A total of 183 reef fish species from 60 families were recorded, of which 166 species were detected using BRUVS and 122 using UVC. Only 66% of all species were detected using both methods. This study showed that the upwelling had an important role in shaping reef fish assemblages in this region, but there was also a significant interaction between upwelling and location. In addition, other drivers such as habitat complexity and habitat composition had an effect on reef fish abundances and species. To authors' knowledge, this is the first study in the Eastern Tropical Pacific that combines BRUVS and UVC to monitor reef fish assemblages in an upwelling region, which provides more detailed information to assess the state of reef ecosystems in response to multiple threats and changing ocean conditions., (© 2020 The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of The Fisheries Society of the British Isles.)

Understanding how threatened species are distributed in space and time can have direct applications to conservation planning. However, implementing standardized methods to monitor populations of wide-ranging species is often expensive and challenging. In this study, we used baited remote underwater video stations (BRUVS) to quantify elasmobranch abundance and distribution patterns across a gradient of protection in the Pacific waters of Costa Rica. Our BRUVS survey detected 29 species, which represents 54% of the entire elasmobranch diversity reported to date in shallow waters (< 60 m) of the Pacific of Costa Rica. Our data demonstrated that elasmobranchs benefit from no-take MPAs, yet large predators are relatively uncommon or absent from open-fishing sites. We showed that BRUVS are capable of providing fast and reliable estimates of the distribution and abundance of data-poor elasmobranch species over large spatial and temporal scales, and in doing so, they can provide critical information for detecting population-level changes in response to multiple threats such as overfishing, habitat degradation and climate change. Moreover, given that 66% of the species detected are threatened, a well-designed BRUVS survey may provide crucial population data for assessing the conservation status of elasmobranchs. These efforts led to the establishment of a national monitoring program focused on elasmobranchs and key marine megafauna that could guide monitoring efforts at a regional scale.

The HLA system shows the most extensive polymorphism in the human genome. Allelic and haplotypic frequencies of HLA genes vary dramatically across human populations. Due to a complex history of migration, populations in Latin America show a broad variety of admixture proportions, usually varying not only between countries, but also within countries. Knowledge of HLA allele and haplotype frequencies is essential for medical fields such as transplantation, but also serves as a means to assess genetic diversity and ancestry in human populations. Here, we have determined high-resolution HLA-A, -B, -C, and -DRB1 allele and haplotype frequencies in a sample of 713 healthy subjects from three Mestizo populations, one population of African descent, and Amerindians of five different groups from Costa Rica and Nicaragua and compared their profiles to a large set of indigenous populations from Iberia, Sub-Saharan Africa, and the Americas. Our results show a great degree of allelic and haplotypic diversity within and across these populations, with most extended haplotypes being private. Mestizo populations show alleles and haplotypes of putative European, Amerindian, and Sub-Saharan African origin, albeit with differential proportions. Despite some degree of gene flow, Amerindians and Afro-descendants show great similarity to other Amerindian and West African populations, respectively. This is the first comprehensive study reporting high-resolution HLA diversity in Central America, and its results will shed light into the genetic history of this region while also supporting the development of medical programs for organ and stem cell transplantation., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Since the year 2000, the number of rapes in Costa Rica has increased at a rate of 42 cases per year. In 2011, 1786 rape cases were reported to the prosecution offices throughout the country, but only 1081 reports continued through the investigation process by the Judicial Investigation Agency. A randomly collected sample of 272 reports received by Judicial Investigation Agency, between July 2012 and June 2013, were prospectively studied. The analysis was limited to cases reported within 30 days following the rape. Results indicate that most of the provinces in the country show an incidence of about 38 cases/100,000 inhabitants. Ninety-six percent of the victims were women, 50% of which were between 10 and 19 years old. More than 99.5% of violators were men. The rape was perpetrated by a single aggressor in 85% of the cases. It was found that 48% of the victims were within the first 11 days of their menstrual cycle at the time of the attack. Twenty-nine percent of rapes occurred in "high rape-risk" circumstances--e.g., victims attacked by strangers in public outdoors or indoors. Twenty-five percent of rapes occur in "moderate rape-risk" circumstances--e.g., victims attacked indoors at public locations or at the home other than the victim's by relatives, sentimental partners or acquaintances. Fifteen percent of rapes occurred in "low rape-risk" circumstances--e.g., victims attacked in their homes by relatives or sentimental partners. In 67% of the cases the perpetrator was an acquaintance of the victim. Eleven percent of the cases corresponded to rapes in which the perpetrator was a partner or ex-partner of the victim. Fourteen percent and 25% of rapes could be classified as "proactive drug-facilitated rapes" or "opportunistic drug-facilitated rapes", respectively. Semen in the vaginal fluid of victims and the genetic profile of the alleged perpetrator were detected in 55% and 33% of the cases, respectively., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

In a collaborative work carried out by the Spanish and Portuguese ISFG Working Group (GEP-ISFG), a polymerase chain reaction multiplex was optimized in order to type ten X-chromosome short tandem repeats (STRs) in a single reaction, including: DXS8378, DXS9902, DXS7132, DXS9898, DXS6809, DXS6789, DXS7133, GATA172D05, GATA31E08, and DXS7423. Using this X-decaplex, each 17 of the participating laboratories typed a population sample of approximately 200 unrelated individuals (100 males and 100 females). In this work, we report the allele frequencies for the ten X-STRs in 15 samples from Argentina (Buenos Aires, Córdoba, Río Negro, Entre Ríos, and Misiones), Brazil (São Paulo, Rio de Janeiro, Paraná, and Mato Grosso do Sul), Colombia (Antioquia), Costa Rica, Portugal (Northern and Central regions), and Spain (Galicia and Cantabria). Gene diversities were calculated for the ten markers in each population and all values were above 56%. The average diversity per locus varied between 66%, for DXS7133, and 82%, for DXS6809. For this set of STRs, a high discrimination power was obtained in all populations, both in males (> or =1 in 5 x 10(5)) and females (> or =1 in 3 x 10(9)), as well as high mean exclusion chance in father/daughter duos (> or =99.953%) and in father/mother/daughter trios (> or =99.999%). Genetic distance analysis showed no significant differences between northern and central Portugal or between the two Spanish samples from Galicia and Cantabria. Inside Brazil, significant differences were found between Rio de Janeiro and the other three populations, as well as between São Paulo and Paraná. For the five Argentinean samples, significant distances were only observed when comparing Misiones with Entre Ríos and with Río Negro, the only two samples that do not differ significantly from Costa Rica. Antioquia differed from all other samples, except the one from Río Negro.

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.

The reefs are heterogeneous systems that maintain a high diversity of organisms. Fish community structure varies within and among reefs, so it would be expected that reef structure and heterogeneity should affect fish communities inhabiting reefs. Four reef patches at Catalinas Islands (Sur, La Pared, Roca Sucia and Sombrero) and one in Ocotal beach (10 degrees 28'45" N; 85 degrees 52'35" W) were studied with visual censuses (July-December 2003). The structure and composition of fishes between Catalinas islands and Ocotal beach were different, and habitat structure and composition explain most of the variance founded. The presence of the fleshy algae Caulerpa sertularioides in Ocotal, and the corals Tubastrea coccinea and Pocillopora spp. at Catalinas Island explained the variability among sites and how it affected fish community structure and composition. The butterfly fish Johnrandallia nigrirostris, damselfish Microspathodon dorsalis, and surgeon fish Prionurus punctatus were directly correlated with the ahermatipic coral Tubastrea coccinea in Roca Sucia reef, while the angel fish Holacanthus passer was associated to reefs with a major percentage of rocky substrate. Other species such as the damselfish Abudefduf troschelli and Halichoeres dispilus were more abundant at Ocotal, where the algae C sertularioides dominated. The number and abundance of reef fishes was directly correlated with the rugosity index at the reefs of Roca Sucia and Ocotal, but not at reefs of La Pared and Sombrero.

The effect of storage temperature on the stability of the liquid polyvalent (crotaline) antivenom produced at the Instituto Clodomiro Picado, Costa Rica, was studied during a twelve-month period. The following parameters were evaluated: neutralizing potency against lethal activity of Bothrops asper venom; protein and phenol concentrations; pH; turbidity; safety; and sterility. Analyses were performed each month on different samples of a batch, stored at 4, 23, 30 and 37 degrees C. No significant (P greater than 0.1) variations occurred in potency, protein and phenol concentrations, pH, sterility or safety, at any of the storage temperatures during the study period. However, visual inspection revealed a moderate increase in turbidity of the samples stored at 23, 30 and 37 degrees C, at nine, four and three months, respectively. Culture of samples excluded the possibility of microbial contamination of the product leading to turbidity. Chromatographic and electrophoretic analyses demonstrated that turbidity was caused by the formation of heterogeneous protein aggregates of high molecular weight. Present results support the conclusion that, although storage temperature (up to 37 degrees C for twelve months) does not alter antivenom potency, it significantly influences the formation of protein aggregates. This phenomenon can be prevented by recommending the storage of antivenom at refrigeration temperature.