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  • Ítem
    Consistent individual positions within roosts in Spix’s disc-winged bats
    (2023-11-28) Giacomini, Giada; Chaves Ramírez, Silvia Elena; Hernández Pinsón, Héctor Andrés; Barrantes, José Pablo; Chaverri Echandi, Gloriana
    Individuals within both moving and stationary groups arrange themselves in a predictable manner; for example, some individuals are consistently found at the front of the group or in the periphery and others in the center. Each position may be associated with various costs, such as greater exposure to predators, and benefits, such as preferential access to food. In social bats, we would expect a similar consistent arrangement for groups at roost-sites, which is where these mammals spend the largest portion of their lives. Here we study the relative position of individuals within a roost-site and establish if sex, age, and vocal behavior are associated with a given position. We focus on the highly cohesive and mobile social groups found in Spix’s disc-winged bats (Thyroptera tricolor) given this species’ use of a tubular roosting structure that forces individuals to be arranged linearly within its internal space. We obtained high scores for linearity measures, particularly for the top and bottom positions, indicating that bats position themselves in a predictable way despite constant roost-switching. We also found that sex and age were associated with the use of certain positions within the roost; for example, males and subadults tend to occupy the top part (near the roost’s entrance) more often than expected by chance. Our results demonstrate, for the first time, that bats are capable of maintaining a consistent and predictable position within their roosts despite having to relocate daily, and that there is a link between individual traits and position preferences.
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    Attitudes and knowledge in high school science: an empirical test of a theoretical model of correlations
    (2023) Quirós Ruiz, Óscar Enrique; Chaverri Echandi, Gloriana; Iturralde Pólit, Paula; Sandí Ureña, Santiago
    It has been discussed that emotional investment in the educational process generates positive cognitive outcomes. This correlation addresses a core tenet of the three learning domains, Cognitive, Affective, and PsychoMotor where all three constitute separate areas of one single learning process. And as such, one would expect to be able to measure this correspondence between the three domains. This study attempts to test the hypothesis of a correlation between the cognitive and affective domains in a cohort of in-service science teachers. Specifically, we seek to assess whether the affective posture towards school sciences shows an association with their cognitive competence in biology, chemistry and physics. We used partial least square regression analysis to examine the data, and the results indicate a direct correlation between the affective and cognitive domains. Teachers who scored higher in cognitive tests for the three sciences also had a more positive attitude towards them. These findings provide strong empirical evidence in support of the theoretical principle that the three domains are separate but interconnected components of the educational process.
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    ohun: An R package for diagnosing and optimizing automatic sound event detection
    (2023) Araya Salas, Marcelo; Smith Vidaurre, Grace; Chaverri Echandi, Gloriana; Brenes Sáenz, Juan Carlos; Chirino Fernández, Fabiola María; Elizondo Calvo, Jorge; Rico Guevara, Alejandro
    1. Animal acoustic signals are widely used in diverse research areas due to the relative ease with which sounds can be registered across a wide range of taxonomic groups and research settings. However, bioacoustics research can quickly generate large data sets, which might prove challenging to analyse promptly. Although many tools are available for the automated detection of sounds, choosing the right approach can be difficult and only a few tools provide a framework for evaluating detection performance. 2. Here, we present ohun, an R package intended to facilitate automated sound event detection. ohun provides functions to diagnose and optimize detection routines, compare performance among different detection approaches and evaluate the accuracy in inferring the temporal location of events. 3. The package uses reference annotations containing the time position of target sounds in a training data set to evaluate detection routine performance using common signal detection theory indices. This can be done both with routine outputs imported from other software and detections run within the package. The package also provides functions to organize acoustic data sets in a format amenable to detection analyses. In addition, ohun includes energy-based and template-based detection methods, two commonly used automatic approaches in bioacoustics research. 4. We show how ohun can be used to automatically detect vocal signals with case studies of adult male zebra finch Taenopygia gutata songs and Spix's disc-winged bat Thyroptera tricolor ultrasonic social calls. We also include examples of how to evaluate the detection performance of ohun and external software. Finally, we provide some general suggestions to improve detection performance.
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    Cave-dwelling fauna of Costa Rica: current state of knowledge and future research perspectives
    (2023) Deleva, Stanimira; Ulloa Carmiol, Andrés; Fernandes Magalhães de Oliveira, Hernani; Simov, Nicolai; Didonna, Ferdinando; Chaverri Echandi, Gloriana
    This study focused on the cave fauna of Costa Rica, which has remained relatively understudied despite the presence of more than 435 recorded natural caves and artificial subterranean sites. We collected and reviewed all available literature data on cave fauna in Costa Rica and created the first comprehensive review of the existing information. In addition, we report new records from field surveys conducted between 2015 and 2018. This study reported approximately 123 animal species, whereas the remaining records (n = 82) represented taxa that could not be identified at the species level. Data were collected from 127 locations throughout the country, with new cave fauna records from 41 sites. Notably, we reported the first occurrence of the true bug Amnestus subferrugineus (Westwood 1837) within Costa Rican caves, which represents an addition to the country’s faunal inventory. As this study highlights the knowledge gaps in the subterranean fauna, it will serve as an important stepping stone for future research and conservation efforts related to caves in Costa Rica.
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    Photosynthetic and morphological acclimation of seedlings of tropical lianas to changes in the light environment
    (2014-12-01) Ávalos Rodríguez, Gerardo; Mulkey, Stephen S.
    Premise of the study: Few studies have analyzed the physiological performance of different life stages and the expression of ontogenetic niche shifts in lianas. Here, we analyzed the photosynthetic and morphological acclimation of seedlings of Stigmaphyllon lindenianum, Combretum fruticosum, and Bonamia trichantha to distinctive light conditions in a tropical dry forest and compared their response with the acclimation response of adult canopy lianas of the same species. We expected acclimation to occur faster through changes in leaf photochemistry relative to adaptation in morphology, consistent with the life history strategies of these lianas. Methods: Seedlings were assigned to the following light treatments: high light (HH), low light (LL), sun to shade (HL), and shade to sun (LH) in a common garden. After 40 d, HL and LH seedlings were exposed to opposite light treatments. Light response curves, the maximum photosynthetic rate in the field (Amax), and biomass allocation were monitored for another 40 d on leaves expanded before transfer. Key results: Photosynthetic responses, Amax, and biomass of Stigmaphyllon and Combretum varied with light availability. Physiological characters were affected by current light environment. The previous light environment (carryover effects) only influenced Amax. Morphological characters showed significant carryover effects. Stigmaphyllon showed high morphological and physiological plasticity. Sun-exposed seedlings of this liana increased stem biomass and switched from self-supporting to climbing forms. Conclusions: Acclimation in seedlings of these lianas is consistent with the response of adult lianas in the canopy in direction, but not in magnitude. There was no evidence for ontogenetic niche shifts in the acclimation response.
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    Effect of prey availability on the abundance of White-breasted Wood-Wrens, insectivorous birds of tropical lowland forests
    (2014-12) Sánchez Ulate, Natalie Viviana; Vargas Castro, Luis Esteban; Ávalos Rodríguez, Gerardo; Paniagua Rodríguez, Federico
    Some understory insectivorous birds manage to persist in tropical forest fragments despite significant habitat loss and forest fragmentation. Their persistence has been related to arthropod biomass. In addition, forest structure has been used as a proxy to estimate prey availability for understory birds and for calculating prey abundance. We used arthropod biomass and forest structural variables (leaf area index [LAI] and aerial leaf litter biomass) to explain the abundance of White-breasted Wood-Wrens (Henicorhina leucosticta), tropical understory insectivorous birds, in six forests in the Caribbean lowlands of Costa Rica. To estimate bird abundance, we performed point counts (100-m radius) in two old-growth forests, two second-growth forests, and two selectively logged forests. Arthropod abundance was the best predictor of wood-wren abundance (wi = 0.75). Wood-wren abundance increased as the number of arthropods increased, and the estimated range of bird abundance obtained from the model varied from 0.51 (0.28 – 0.93 [95%CI]) to 3.70 (1.68 – 5.20 [95%CI]) within sites. LAI was positively correlated to prey abundance (P = 0.01), and explained part of the variation in wood-wren abundance. In forests with high LAI, arthropods have more aerial leaf litter as potential habitat so more potential prey are available for wood-wrens. Forests with a greater abundance of aerial leaf litter arthropods were more likely to sustain higher densities of wood-wrens in a fragmented tropical landscape.
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    Influence of light conditions on the allometry and growth of the understory palm Geonoma undata subsp. edulis (Arecaceae) of neotropical cloud forests
    (2013-12-01) Sylvester, Olivia; Ávalos Rodríguez, Gerardo
    Premise of the study: Knowledge on the growth responses of understory palms to changing light conditions within neotropical cloud forests is limited. The low light regime of these environments, in addition to persistent cloudiness, low ambient temperatures, and slow nutrient cycles, imposes significant constraints on biomass accumulation. Here, we evaluate how changes in the understory light conditions influenced the allometry and growth of G. undata subsp. edulis in two cloud forests in Costa Rica. Methods: We examined the structural relationships between stem diameter, stem height, and crown area in reproductive and nonreproductive individuals. We related the variation in stem growth and crown area with allometry, leaf production and longevity, and light conditions that we measured using hemispherical photographs over 1 year. Key results: The allometric and growth pattern of G. undata subsp. edulis was characterized by its investment in crown area, which was strongly and positively related to increments in palm height and reproduction. Growth, measured as the increase in crown area and stem height, was not explained by the variation in the light regime spanning 1 year. However, reproductive individuals were generally taller, more slender, and had larger leaf areas than nonreproductive individuals. Conclusions: Our results demonstrated that stem growth responses were mostly controlled by initial crown size rather than by temporal differences in the understory light regimes of cloud forests. These results suggest that cloud forest understory palms have a limited capacity to respond to light changes and rely mostly on an opportunistic strategy for biomass accumulation and reproduction.
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    Notes on the Ethnobotany of Costa Rica's palms
    (2012) Sylvester, Olivia; Ávalos Rodríguez, Gerardo; Chávez Fernández, Nuria
    To support the implementation of policies that recognize human uses of wild plants, we documented palm ethnobotany within or bordering eight protected areas in Costa Rica. Through participant observation and semi-structured interviews with 37 participants from 18 communities, we documented the cultivation and harvest of 32 palm species from 21 genera. We also reported uses of five palms (Cryosophila warscewiczii, Bactris gasipaes, Desmoncus costaricensis, Elaeis oleifera, Pholidostachys pulchra) that, to our knowledge, were previously undescribed in the literature.
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    Divergence in functional traits in seven species of neotropical palms of different forest strata
    (2023-10-24) Ávalos Rodríguez, Gerardo; Cambronero Quesada, Milena; Álvarez Vergnani, Carolina
    Functional traits are morphological and physiological characteristics that determine growth, reproduction, and survival strategies. The leaf economics spectrum proposes two opposing life history strategies: species with an “acquisitive” strategy grow fast and exploit high-resource environments, while species with a conservative” strategy emphasize survival and slow growth under low resource conditions. We analyzed intra and interspecifc variation in nine functional traits related to biomass allocation and tissue quality in seven Neotropical palm species from understory and canopy strata. We expected that the level of resources of a stratum that a species typically exploits would determine the dominance of either the exploitative or conservative strategy, as well as degree of divergence in functional traits between species. If this is correct, then canopy species will show an acquisitive strategy emphasizing traits targeting a larger size, whereas understory species will show a conservative strategy with traits promoting efcient biomass allocation and survival in the shade. Two principal components (57.22% of the variation) separated palm species into: (a) canopy species whose traits were congruent with the acquisitive strategy and emphasized large size (i.e., diameter, height, carbon content, and leaf area), and (b) understory species whose traits were associated with efcient biomass allocation (i.e., dry mass fraction -DMF- and tissue density). As we unravel the variation in functional traits in palms, which make up a substantial proportion of the tropical fora, we gain a deeper understanding of how plants adapt to environmental gradients.
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    Influencia de características del hábitat urbano sobre la composición de escamas armadas (Coccomorpha: Diaspididae) y regulación por enemigos naturales en las palmas Dypsis lutescens y Phoenix roebeleni
    (2024) Solano Gutiérrez, Minor Vicente; Hanson, Paul
    El paisaje urbano es un hábitat alterado por el humano derivado de tierras naturales o agrícolas, que destaca principalmente por las plantas como su componente biológico más visible. Las palmas ornamentales, vitales en contextos urbanos tropicales, contribuyen a la biodiversidad y ofrecen servicios ecosistémicos esenciales. Sin embargo, la presencia de escamas armadas (Hemiptera: Diaspididae) como plagas perturba este equilibrio, destacando la necesidad de un enfoque ecológico en el manejo de plagas en espacios verdes urbanos. Se hipotetiza que las características del hábitat urbano, como la cobertura vegetal a nivel del paisaje, la complejidad estructural de la comunidad vegetal y el porcentaje de superficie impermeable, podrían funcionar como factores reguladores para las poblaciones de escamas armadas al disminuir la abundancia de estas y promover el control por enemigos naturales. Se estudió el impacto de estas características del hábitat urbano en la abundancia y composición de especies de escamas armadas y la mortalidad por enemigos naturales en las palmas Dypsis lutescens y Phoenix roebelenii en áreas urbanas de Costa Rica, dos de las especies de palmas más comúnmente encontradas en estos entornos. Se identificaron un total de 12 especies de escamas armadas. Se confirma la presencia de Lopholeucaspis cockerelli (Grandpre & Charmoy), reportada por primera vez en 1953 en material vegetal interceptado de Costa Rica. Esta especie se identificó en P. roebelenii (nuevo registro de hospedero) y D. lutescens. De manera similar, Pseudischnaspis bowreyi (Cockerell) se identificó en D. lutescens (nuevo registro de hospedero) y P. roebelenii (nuevo registro de hospedero). P. bowreyi se registró anteriormente solo en material vegetal interceptado de Costa Rica. Además, se identificó a Ischnaspis longirostris (Signoret) en ambas especies de palmas, Selenaspidus articulatus (Morgan) en P. roebelenii (nuevo registro de hospedero), Hemiberlesia cyanophylli (Signoret) en P. roebelenii (nuevo registro de hospedero) y D. lutescens, H. palmae (Cockerell) en P. roebelenii (nuevo registro de hospedero) y D. lutescens, Pinnaspis strachani (Cooley) en D. lutescens, P. apidistrae (Signoret) en D. lutescens y P. roebelenii (nuevo registro de hospedero), Diaspis boisduvalii Signoret en P. roebelenii, Chrysomphalus dictyospermi (Morgan) en P. roebelenii (nuevo registro de hospedero) y D. lutescens (nuevo registro de hospedero), Lepidosaphes gloverii (Packard) en P. roebelenii (nuevos registros de hospedero) y Aspidiotus destructor Signoret en ambas especies de palmas. Se obtuvieron los parasitoides Aphytis sp. (Hymenoptera: Aphelinidae) de C. dictyospermi e I. longirostris y Signiphora sp. (Hymenoptera: Signiphoridae) de H. cyanophylli e I. longirostris. Esto marca el primer registro de la asociación ecológica entre Signiphora e I. longirostris. Nuestro estudio reveló un aumento significativo en la abundancia de escamas armadas en respuesta a la disminución de la complejidad estructural de la comunidad vegetal y el aumento de la superficie impermeable. Estas tendencias de abundancia reflejan la naturaleza especializada de las escamas armadas, destacando su adaptabilidad a condiciones urbanas alteradas. Sin embargo, la simplificación del entorno urbano presenta desafíos para niveles tróficos superiores, evidenciados por tasas bajas de parasitismo. Las tasas de depredación se vieron afectadas por los porcentajes de superficie impermeable, la riqueza de plantas y la abundancia de palmas en el entorno, subrayando el papel crucial de la cobertura vegetal para conservar depredadores. Nuestros hallazgos enfatizan la necesidad de una planificación estratégica de conservación en los paisajes urbanos neotropicales para proteger el delicado equilibrio entre las escamas armadas, sus enemigos naturales y el paisaje.
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    Global biogeography and diversification of a group of brown seaweeds (Phaeophyceae) driven by clade-specific evolutionary processes
    (2021-01-07) Vieira, Christophe; Steen, Frédérique; D'hondt, Sofie; Bafort, Quinten; Tyberghein, Lennert; Fernández García, Cindy; Wysor, Brian; Tronholm, Ana; Mattio, Lydiane; Payri, Claude E.; Kawai, Hiroshi; Saunders, Gary; Leliaert, Frederik; Verbruggen, Heroen; De Clerck, Olivier
    Aim: Historical processes that shaped current diversity patterns of seaweeds remain poorly understood. Using Dictyotales, a globally distributed order of brown seaweeds as a model, we test if historical biogeographical and diversification patterns are com- parable across clades. Dictyotales contain some 22 genera, three of which, Dictyota, Lobophora and Padina, are exceptionally diverse. Specifically, we test whether the evolutionary processes that produced the latitudinal diversity patterns in these clades are in line with the tropical conservatism, out-of-the-tropics or diversification rate hypotheses. Location: Global coastal benthic marine environments. Taxon: Dictyotales (Phaeophyceae). Methods: Species diversity was inferred using DNA-based species delineation, addressing cryptic diversity and circumventing taxonomic problems. A six-gene timecalibrated phylogeny, distribution data of 3,755 specimens and probabilistic modelling of geographical range evolution were used to infer historical biogeographical patterns. The phylogeny was tested against different trait-dependent models to compare diversification rates for different geographical units as well as different thermal affinities.Results: Our results indicate that Dictyotales originated in the Middle Jurassic and reach a current peak of species diversity in the Central Indo-Pacific. Ancestral range estimation points to a southern hemisphere origin of Dictyotales corresponding to the tropical southern Tethys Sea. Our results demonstrate that diversification rates were generally higher in tropical regions, but increased diversification rates in different clades are driven by different processes. Our results suggest that three major clades underwent a major diversification burst in the early Cenozoic, with Dictyota and Padina expanding their distribution into temperate regions while Lobophora retained a predominantly tropical niche. Main conclusions: Our results are consistent with both the tropical conservatism hypothesis, in which clades originate and remain in the tropics (Lobophora), and the out-of-the-tropics scenario, where taxa originate and expand towards the temperate regions while preserving their presence in the tropics (Dictyota, Padina).
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    Levelling-up rhodolith-bed science to address global-scale conservation challenges
    (2023) Tuya, Fernando; Schubert, Nadine; Aguirre, Julio; Basso, Daniela; Bastos, Eduardo; Berchez, Flavio; Bernardino, Angelo; Bosch, Néstor E.; Burdett, Heidi L.; Espino, Fernando; Fernández García, Cindy; Francini Filho, Ronaldo B.; Gagnon, Patrick; Hall Spencer, Jason M.; Haroun, Ricardo; Hofmann, Laurie C.; Horta, Paulo A.; Kamenos, Nicholas A.; Le Gall, Line; Magris, Rafael A.; Martin, Sophie; Nelson, Wendy A.; Neves, Pedro; Olivé, Irene; Otero Ferrer, Francisco; Peña, Viviana; Pereira Filho, Guilherme H.; Ragazzola, Federica; Rebelo, Ana Cristina; Ribeiro, Cláudio; Rinde, Eli; Shoenrock, Kathryn; Silva, João; Sissini, Marina N.; Tâmega, Frederico Tapajós de Souza
    Global marine conservation remains fractured by an imbalance in research efforts and policy actions, limiting progression towards sustainability. Rhodolith beds represent a prime example, as they have ecological importance on a global scale, provide a wealth of ecosystem functions and services, including biodiversity provision and potential climate change mit- igation, but remain disproportionately understudied, compared to other coastal ecosystems (tropical coral reefs, kelp for- ests, mangroves, seagrasses). Although rhodolith beds have gained some recognition, as important and sensitive habitats at national/regional levels during the last decade, there is still a notable lack of information and, consequently, specific conservation efforts. We argue that the lack of information about these habitats, and the significant ecosystem services they provide, is hindering the development of effective conservation measures and limiting wider marine conservation success. This is becoming a pressing issue, considering the multiple severe pressures and threats these habitats are exposed to (e.g., pollution, fishing activities, climate change), which may lead to an erosion of their ecological function and eco- system services. By synthesizing the current knowledge, we provide arguments to highlight the importance and urgency of levelling-up research efforts focused on rhodolith beds, combating rhodolith bed degradation and avoiding the loss of associated biodiversity, thus ensuring the sustainability of future conservation programs.
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    Lesions in octocorals of the Costa Rican Caribbean during the 2015-2016 El Niño
    (2021-06-01) Calderón Hernández, Alejandra; Urbina Villalobos, Andrea María; Mora Barboza, Cristián; Morales Acuña, Juan Alberto; Fernández García, Cindy; Cortés Núñez, Jorge
    Emerging infectious diseases affecting marine ecosystems are increasing worldwide. Nevertheless, there are very few histopathological analyses describing the tissue damage associated with a specific disease. This makes it difficult to study the host response and to relate the findings to the isolated agent. Octocoral disease research has focused on the observation of lesions and on the identification of the potential pathogens involved. The aim of this investigation was to identify macroscopic lesions and describe histopathological findings in octocorals to determine potential causes. Fifty-five octocorals were investigated, and 18 of them had visible lesions (32.7%). Samples from the injured tissues of nine individuals of Gorgonia spp., seven individuals of Eunicea spp., one individual of Plexaurella dichotoma and one individual of Pseudopterogorgia acerosa were collected and processed for histopathological analysis. Algal and crustacean abrasions were the main causes of lesions detected in the field. Lesions with a focal distribution were present in most of the colonies, together with changes in tissue coloration. Histopathology revealed that melanization, amoebocytosis and polyp necrosis were the main reactions associated with algae and crustaceans. Histopathology allowed us to confirm the algae and crustacean involvement even when they were not macroscopically evident by the tissue damage and the associated response of these octocorals.
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    Gelidium gonzalezii sp.nov. (Gelidiales, Rhodophyta) from the Mexican tropical Pacific based on molecular and morphological evidence
    (2020-09-11) Quiroz González, Nataly; Ponce Márquez, María Edith; Fernández García, Cindy; Rodríguez Vargas, Dení Claudia
    There are currently 23 reported species of Gelidium in Mexican Pacific coastal waters. Many of these species require taxonomic verification. Gelidium sclerophyllum is a species reported from the northern Gulf of California to the tropical region of the Mexican Pacific, but there is large morphological variation among populations. The objective of this research was to evaluate this species using a morphological and molecular approach, with COI-5P and rbcL molecular markers. A total of 13 samples were collected from five sites in the Mexican Tropical Pacific. Phylogenetic analyses resolved these specimens within a separate clade from that which includes the type of G. sclerophyllum and other Central American specimens. Differences with other species are subtle and based mainly on size, branching pattern, shape of tetrasporangia sori and size of tetraspores. The sequence divergences and the subtle morphological differences between these two clades support their recognition as two distinct species, and Gelidiumgonzalezii sp. nov. is proposed for specimens from the Mexican Tropical Pacific.
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    Ampliación del ámbito de distribución y primer registro de Colpomenia tuberculata (Ectocarpales, Scytosiphonaceae) para Nayarit, México
    (2020) Quiroz González, Nataly; Fernández García, Cindy; León Álvarez, Daniel
    Se registraron por primera vez especímenes de un alga parda con una morfología que coincide con Colpomenia tuberculata en Nayarit. Se recolectaron muestras en dos localidades, playa Islitas y playa Platanitos, el material fue identificado empleando caracteres morfológicos vegetativos y reproductivos. Estos nuevos registros representan la expansión hacia el sur a zonas tropicales de una especie previamente considerada de distribución en aguas subtropicales, templadas y frías.
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    New records of benthic marine macroalgae from the Caribbean coast of Costa Rica
    (2018-04) Vega Álvarez, Greivin; Azofeifa Solano, Juan Carlos; Fernández García, Cindy; Soto Molinari, Rebeca; Rojas Angulo, Maricruz; Amador Fernández, Xaviera; Vargas Gamboa, Ajejandra
    Marine macroalgae are highly diverse and play an important role in marine ecosystems, influencing ecological processes. Recording the algae diversity with precise taxonomic identification is required to under- stand the marine ecosystems. The biodiversity of macroalgae along the southern Caribbean coast of Costa Rica has been studied by several authors, and the updated checklist includes 396 species of benthic marine algae reported for both Pacific and Caribbean coasts of Costa Rica, from which 287 are recorded from the Caribbean. Eighty percent of the total specimens from the Caribbean coast deposited in botanical collections in Costa Rica were collected at Cahuita National Park, an area where most of the studies have been carried out. This study reports on the addition of five new species and one genus of marine benthic macroalgae to the Caribbean Costa Rican flora, found at the poorly studied reefs of Playa Chiquita (Punta Cocles) and Punta Uva. Sampling was directed, searching for benthic macroalgae at Chiquita beach (SCUBA diving and snorkel) and Punta Uva (snorkel only), during October 2014. Specimens were deposited in the Dr. Luis A. Fournier Origgi Herbarium of the University of Costa Rica (USJ). Most of the new records were Chlorophyta, followed by Rhodophyta and Ochrophyta-Phaeophyceae. We recorded four new genera for the Caribbean coast of Costa Rica: Microdictyon Decaisne, 1841, Rhipidosiphon Montagne, 1842, Predaea G. De Toni, 1936, and Augophyllum S.-M. Lin, S. Fredericq & M. H. Hommersand, 2003. In conclusion, is necessary to continue the detailed taxonomic works in the Caribbean coast, focusing on areas poorly studied, in order to improve our knowledge of the marine flora of Costa Rica.
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    Size and distribution of rhodolith beds in the Loreto Marine Park: their role in coastal processes
    (2012-01) Riosmena Rodríguez, Rafael; Lopez Calderón, Jorge Manuel; Mariano Melendez, Everardo; Sánchez Rodríguez, Alexandra; Fernández García, Cindy
    Size, species, growth form, and rhodolith-bed distribution in the Loreto Marine Park were evaluated, based on sampling undertaken in June and December 2009 and 2010. Extensive surveys on nine major beds were performed using global positioning system and scuba methodologies with the goals of determining (1) the size and distribution of rhodolith beds along the central Loreto Marine Park area, (2) the physical structure of the beds, and (3) the species and growth-form composition. We found a total of 732.8 ha of the seafloor covered by rhodolith beds, of which several islands (Coronado and Carmen) and some coastal areas (between Ensenada Blanca and Puerto Escondido) represented the most extensive accumulations. Most of the studied beds were composed by living material, but in the bed located off the south end of Carmen Island a ratio of 50:50 living-to-dead rhodoliths was discovered. Three species were found commonly to compose the beds (Lithophyllum margaritae, Neogoniolithon trichotomum, and Lithothamnion muellerii), whereas only two growth forms were present (fruticose and incrusting) dominating the beds. Branch density, rhodolith density, and sphericity were found to be similar in all sampling areas. This suggests that the various beds are related to main currents within the park. However, incrusting growth forms and densely branched fruticose plants were only present in the bed from the Danzante area. This suggests that the presence of a rocky bottom is relevant to the composition of growth forms. Results of this study strongly suggest that rhodolith beds contribute to coastal processes by constantly producing sand derived from broken material. In addition, the extensive cover by rhodoliths is significantly high for the shallow areas surveyed. Future surveys into deeper waters and other areas to more fully understand the role of rhodoliths and their taphonomy in coastal areas are needed.
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    Ambientes y organismos marinos de la Reserva Biológica Isla del Caño, Área de Conservación Osa, Costa Rica
    (2009) Cortés Núñez, Jorge; Guzmán Espinal, Héctor M.; Fonseca Escalante, Ana Cecilia; Alvarado Barrientos, Juan José; Fernández García, Cindy; Breedy Shadid, Odalisca; Segura Ruiz, Álvaro; Ruiz Campos, Eleazar
    La Reserva Biológica Isla del Caño es parte del Área de Conservación Osa (ACOSA) y está ubicada a 15 km de la Península de Osa, en el Pacífico sur de Costa Rica. La isla tiene varias playas y está rodeada de plataformas rocosas y coralinas, de arrecifes coralinos, fondos arenosos y lechos de rodolitos. En algunas zonas rocosas submarinas crecen gran diversidad de especies de octocorales. Cerca de la Isla del Caño hay muchos cetáceos y es un área donde las ballenas jorobadas tienen sus crías. En esta publicación se presenta un mapa batimétricos de la Isla del Caño, perfiles del fondo en varias direcciones perpendiculares a la isla, mapas de los hábitats marinos, listas de especies marinas, una lista con los trabajos científicos que se han publicado sobre organismos, ambientes y procesos marinos de la isla y se da una serie de recomendaciones para el manejo adecuado de los ambientes marinos. La Isla del Caño esta rodeada por una plataforma submarina irregular en extensión y profundidad. En los lados oeste, norte y este la plataforma termina a unos 40 m de profundidad y se hace más profunda poco a poco. Del lado sur la pendiente es pronunciada hasta los 80 m y de ahí en adelante la pendiente es mucho menor. El mapa de hábitat generado con la imagen Hymap (CARTA 2005) tiene una exactitud del 60%, mientras, que la exactitud del mapa a partir de la imagen QuickBird fue mayor (87%). A partir de la clasificación de hábitats con la imagene Quickbird, los arrecifes coralinos representan el 13%, mientras que las comunidades coralinas ocuparon el 14% de los ambientes someros. La cobertura de coral vivo en la Isla del Caño ha venido aumentando desde su reducción drástica durante El Niño 1982-83. La diversidad marina de la isla es muy rica, en este trabajo se registran 239 especies entre las informadas en la literatura científica y lo observado y recolectado durante una expedición en enero-febrero 2007. Esto representa un aumento de más del 50% de las especies que habían sido informadas previamente. Falta más investigación en la Isla del Caño ya que hay muchos grupos de los que no hay registros. Durante la expedición se encotraron 37 especies de algas en cuatro Divisiones, se identificaron 20 especies de octocorales, dos de coral negro y 21 de corales escleractinios, y se contabilizaron 82 especies de peces, pertenecientes a 33 familias. Haciendo de la Isla del Caño el sitio más rico del país de varios grupos de organismos marinos. Adicionalmente, en la Isla del Caño todavía se puede observar coral negro a relativamente poca profundidad, se ven cambutes grandes y especies de peces de importancia comercial en grandes números y tamaño, cosa que ya no se ve fuera de las áreas protegidas. Estas especies comerciales incluyen peces extraídos para consumo directo, como para el negocio de acuarios en sitios no protegidos y están escaseando, pero en la Reserva Biológica Isla del Caño son abundantes. La lista de artículos científicos sobre organismos, ambientes y procesos marinos incluye 84 referencias, que van desde contaminación hasta taxonomía de varios organismos, pasando por impactos naturales y antropogénicos en los arrecifes coralinos de la isla. La mayoría de los trabajos son sobre los arrecifes coralinos y sus organismos asosciados. La Isla del Caño está bajo gran presión por el turismo, por la pesca deportiva, pesca comercial ilegal y anclaje de todo tipo de lanchas y barcos, tanto de turismo como de pesca y camaroneros. Hay contaminación con líquidos y sólidos. Por esto se debe mantener las cuotas de visitante y las áreas designadas para el buceo, prohibir totalmente la pesca dentro del área protegida que debe extenderse al menos 6 km desde la orilla, y se debe limitar totalmente la entrada de embarcaciones de pesca de todo tipo. Es recomendable aumentar el personal y los recursos para poder realizar una mejor vigilancia de los ambientes marinos. Se debe incentivar la investigación científica en la Reserva Biológica. Finalmente, por la gran diversidad de hábitats y especies de la Reserva Biológica Isla del Caño se debe considerar su inclusión en la Iniciativa del Corredor Marino del Pacífico Tropical Oriental, como otro de los sitios de Costa Rica.
  • Ítem
    Status of coral reefs and associated ecosystems in Southern Tropical America: Brazil, Colombia, Costa Rica, Panamá and Venezuela
    (2008) Rodríguez Ramírez, Alberto; Bastidas, Carolina; Cortés Núñez, Jorge; Guzmán, Héctor M.; Leão, Zelinda; Garzón Ferreira, Jaime; Kikuchi, Ruy; Padovani Ferreira, Beatrice; Alvarado Barrientos, Juan José; Jiménez Centeno, Carlos; Fonseca Escalante, Ana Cecilia; Salas De la Fuente, Eva María; Nivia Ruiz, Jaime; Fernández García, Cindy; Rodríguez, Sebastian; Debrot, Denise; Cróquer, Aldo; Gil, Diego L.; Gómez López, Diana Isabel; Navas Camacho, Raúl; Reyes Nivia, María Catalina; Acosta, Alberto; Alvarado Ch., Elvira M.; Pizarro, Valeria; SanJuan, Adolfo; Herrón, Pilar; Zapata, Fernando A.; Zea, Sven; López Victoria, Mateo; Sánchez, Juan Armando
    Algae are the most abundant reef organisms in most of the countries; high coral cover does occur at numerous reef locations at the Caribbean (~70%) and Pacific (~95%) coasts. No major changes in live coral cover have been observed recently in the region; some localised decline and recovery trends are evident for each country. Coral reefs in the region experience many natural and human threats, and predictions suggest that nearly 50% of reefs are at very low risk of decline in 5-10 years, even considering global climate change, and around 40% of reefs could be under high risk of decline in the mid-long term (>10 years). Massive coral bleaching occurred in southern tropical America during 2005, but the severity varied across the region. Reef monitoring has increased, but low funding for monitoring programs occurs all countries; socio-economic monitoring is restricted to Brazil. Information on reef fisheries from monitoring programs is scarce, however, the consensus is for depletion of coral reefs resources, particularly in the Caribbean; and seagrass and mangrove communities are mainly threatened by coastal development, sedimentation, pollution, and deforestation.
  • Ítem
    Flora Marina del Parque Nacional Isla del Coco, Costa Rica, Pacífico Tropical Oriental
    (2008) Fernández García, Cindy
    Se presenta una descripción preliminar de la flora marina alrededor de la Isla del Coco como base para evaluar cambios a largo plazo. La recolección de datos se realizó en dos expediciones (setiembre 2006 y enero 2007). Las algas fueron removidas por medio de una cuchilla y preservadas en una solución amortiguada de formalina al 4%. Para determinar el porcentaje de cobertura se realizaron tres transectos de 10 m de longitud a dos profundidades (6 y 15 m), en cinco sitios. En total se identificaron 29 especies de macroalgas, de las cuales 10 pertenecen a la División Chlorophyta, representada por géneros ampliamente dis- tribuidos como Ulva, Cladophora y Caulerpa. Seis espe- cies pertenecen a la Clase Phaeophyta, en dos familias Sytosiphonaceae y Dictyotaceae. La División Rhodophyta constituyó el grupo más diverso de macroalgas de la Isla del Coco con un total de 13 especies. Las macroalgas cubren en promedio 50.7+27.4% a 6 m y 47.1+16.1% a 15 m del sustrato. Las algas con mayor cobertura y mayor distribución alrededor de la isla fueron Cladophora sp., Dictyota sp., Polysiphonia sp. y las algas calcáreas (41% de cobertura en algunos sitios). Las macroalgas conforman un gran porcentaje del bentos en los ambientes arrecifales, asegurando su relevancia ecológica.