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The sea surface temperature and surface currents during 1993–2016 based on satellite remote sensing, along with the ocean temperature and currents during 1993–2013 from a data assimilative ocean simulation product, are analyzed to investigate the influence of the Galápagos Islands (GI) in the eastern tropical Pacific on the sea surface temperature. Variations of the cold core west of the GI are quantified by TC − TW, TC − TE, and the cold core area (CCA), where TW, TC, and TE are the sea surface temperature to the west of the cold core, in the cold core, and to the east of the GI, respectively. TC − TE and the CCA show a stronger influence of the GI in boreal fall than in spring, in contrast to TC − TW, which shows a stronger influence in spring than in fall. All three indices show weaker (stronger) GI's influence during El Niño (La Niña) years, but only CCA and TC − TE have significant correlations of −0.66 and 0.61 with the Niño3 index. Variations of TC − TW are related to that of upwelling immediately the west of the GI. Variations of TC − TE and CCA are related to that of the spatial distributions of the upper ocean temperature, the advection of temperature by the horizontal currents, specifically the north branch of the South Equatorial Current, and upwelling in the eastern tropical Pacific. Key Points: Two new indices are defined to quantify the influence of Galápagos Islands on SST in Eastern Tropic PacificNew indices show stronger (weaker) Islands' influence in boreal fall (spring) and during La Niña (El Niño) yearsVariations of the Islands' influence are related to distributions of background temperature, upwelling, and surface currents [ABSTRACT FROM AUTHOR]

Porites panamensis is a hermatypic brooder coral endemic to, and distributed along, the Eastern Tropical Pacific, and is considered a species vulnerable to local effects because it has limited capacity for long‐distance dispersal (and low genetic diversity). Although larvae of P. panamensis have been previously shown to recruit to artificial settlement platforms, they have never been observed in the water column. The present study describes the reproductive behavior of P. panamensis, with a focus on using molecular tools to document evidence for a larval planktonic stage and for successful recruitment. Larvae collected from the water column, and recruitment on natural and artificial substrata were documented. Phylogenetic analysis of two ribosomal markers, 18s rRNA and ITS (ITS1‐5.8‐ITS2), and one mitochondrial marker, cytochrome oxidase subunit 1 (cox1), confirmed the taxonomic identity of larvae, and showed that larvae and recruits have genotypes similar to adults of P. panamensis. Lipid vacuoles and Symbiodinium sp. were present in the gastrodermis of all larvae. A total of 12 and 371 recruits settled on artificial and natural substrates, respectively, and the recruitment rate differed significantly over time. By documenting the reproductive success of the species, we show the potential for existing individuals both to maintain the population in the study area and to contribute to maintenance of the coral reef community in the coming decades. [ABSTRACT FROM AUTHOR]

Abstract The recruitment of marine invertebrate larvae to coral reef ecosystems is critical for the continued productivity of these highly biodiverse habitats. Despite such importance, little is known about temporal variation patterns of invertebrate larval recruitment in coral reefs ecosystems, aside from studies focused only on reef corals themselves. Given this knowledge deficiency, recruitment onto dead coral branches was monitored over a one-year period in the Central Mexican Pacific, and recruit assemblage and density both changed over time. In particular, recruitment was higher in the warmer months, possibly due to reproductive processes and/or increases in metabolic rates associated with high temperatures and seasonal/local events such as upwellings that increase the food resources available for the recruits which just before the warm season, when the recruitment is more more prevalent during the warm season. The most common invertebrate recruits were malacostracans, ostracods, gastropods, maxillopods, and polychaetes, and foraminifers were commonly observed, as well. Future works in this region will seek to understand whether recruit density and diversity change in response to elevated temperatures associated with global climate change. Highlights • Invertebrates are one of the most abundant group associated to a coral reef ecosystem. • Dead coral was used as recruitment substrata, allowing to asses invertebrate recruitment. • The presence of benthonic groups such as algae and turf benefits the recruitment. • A temporal variation on the recruitment was determined, associated with the SST. [ABSTRACT FROM AUTHOR]

This study reports the first record of a white shark Carcharodon carcharias off the tropical coast of Nayarit and the southernmost record in the Mexican Pacific. The specimen was a juvenile female accidentally caught by artisanal fisheries in the locality of Playa Novillero, Nayarit. Oceanographic conditions at the time of capture were also recorded, with the aim of improving the knowledge on the ecology of this vulnerable and protected species. [ABSTRACT FROM AUTHOR]

Highlights • Outplanting corals of opportunity was an effective tool for long-term restoration. • Pocillopora spp. increased two and fourth-times in growth and ecological volume. • After five years of coral restoration, coral cover and carbonate production doubled. Abstract Ongoing climate change and frequent anomalous thermal events have greatly contributed to the deterioration of coral reefs worldwide, exacerbating declines in coral reef formation and ecosystem service provision. Under this climate change scenario, the development and improvement of restoration techniques will be required to cope with coral reef degradation. This study demonstrates the potential use of direct relocation of coral of opportunity as an effective long-term ecological restoration tool. We assessed coral growth parameters (cm yr−1), attachment rate (%), ecological volume (cm3 yr−1), including long-term evaluation of annual live coral cover (%) and calcium carbonate production (kg CaCO 3 m−2 yr−1) during 5-years (2013–2018) using resilient branching coral Pocillopora spp. The results show a survivorship of 67%, high self-attachment (100%) during the first 6-months, and size augmentation of ∼167% in growth parameters (2.94–4.47 cm yr−1) and ∼418% in ecological volume. Over the long-term, live coral cover increased from 13 to 28% (+4% per year) with an accumulated carbonate production of 14.53 kg CaCO 3 m−2 (∼3 kg CaCO 3 m−2 yr−1) resulting from the restoration process, and we found evidence for high resistance and recovery after periods of thermal anomalies. The data validate the use of direct propagation of corals of opportunity as a one of the most feasible and practical techniques to long-term restoration of damaged and degraded coral reef areas, which may help in their structural rehabilitation, improving coral communities and biodiversity maintenance. [ABSTRACT FROM AUTHOR]

Knowledge of metabolic rates of euphausiid diel vertical migrants in the ocean is of paramount importance to understand the role of these organisms in the downward transport of carbon due to their feeding in the epipelagic zone and subsequent respiration, egestion, excretion and mortality in the mesopelagic zone. Enzymatic activities are used as proxies for the estimation of metabolism in deep waters because of the logistical problems related to measure these rates at depth. However, metabolic activities of euphausiids in the so-called oxygen minimum zones (OMZs) are still not well understood. The OMZs are expanding as the effect of the global warming. Knowledge about the metabolic response of organisms transiting these zones will help to understand the fate of zooplanktonic communities and vertical active flux. The electron transport system (ETS) and aminoacyl-tRNA synthetases (AARS) activities were used as proxies for potential respiration and growth in planktonic organisms. Here, we measured these enzymatic activities in Euphausia distinguenda in the well-oxygenated epipelagic layer and in the OMZ of the northern boundary of the Eastern Tropical Pacific off Mexico. E. distinguenda was found in the mixed layer at night (~3.5 mL O2 L−1) and near the core of the OMZ (0.2 mL O2 L−1) during daytime between 200 and 350 m depth. We found higher ETS and AARS specific activities in the warm mixed layer at night and significantly lower in the colder OMZ during daytime because of temperature differences. However, when the effect of temperature was subtracted in both enzyme activities, higher values in the mesopelagic layer were observed. This result is tentatively explained by the increase in substrates as the effect of feeding at night in the upper layers and their oxygen consumption at depth during day in order to compensate for the colder temperature and low dissolved oxygen concentration. This physiological mechanism allows E. distinguenda diel vertical migrants to partly face the physical constraints of vertical migration imposed to avoid predators. [ABSTRACT FROM AUTHOR]

The Galápagos Islands are recognized for their unique biota and are one of the world's largest marine protected areas. While invasions by non-indigenous species are common and recognized as a significant conservation threat in terrestrial habitats of the Archipelago, little is known about the magnitude of invasions in its coastal marine waters. Based upon recent field surveys, available literature, and analysis of the biogeographic status of previously reported taxa, we report 53 non-indigenous species of marine invertebrates in the Galápagos Islands. Forty-eight (90.6%o) of these species are newly reported or newly recognized as introduced, a nearly ten-fold increase from the five species previously recognized as non-indigenous. Of these 48 species, 30 (62.5%) were newly discovered in surveys commenced in 2015. Ascidians (11 species), bryozoans (10), polychaetes (9), and hydroids (8) account for 38 (71.7%) of the introduced species. Our analyses farther detected 33 cryptogenic invertebrate and algal species and one littoral vascular plant. Most taxonomic groups remain to be assessed for the presence of non-indigenous species. Importantly, the recent field surveys were restricted predominantly to one habitat (harbor biofouling) on two islands, farther suggesting that introduced species richness for the Galápagos Islands may be considerably higher. Most of the introduced species treated here were likely brought to the Galápagos by ships. While we presume that most if not all of the many thousands of vessels arriving in the Galápagos Islands since the 1500s had marine animals and plants attached to their hulls, we hypothesize that the general absence in the Islands of extensive shoreline structures (in the form of wharves, docks, pilings, and buoys) until the last half of the 20th century may have constrained extensive colonization by fouling species. The proliferation of shoreline structures may have both provided expanded habitat for non-indigenous species that had earlier colonized natural substrates, as well as having facilitated a 20th and 21st century wave of new invasions in the Galápagos Islands. Our results represent the greatest reported increase in the recognition of the number of invasions for any tropical marine environment in the world. This work suggests that the number and potential ecological impacts of non-indigenous species in tropical marine and maritime habitats may be substantially underestimated in other regions of the world. Our study demonstrates that tropical marine invasions deserve significant attention, not only in a biogeographical, historical, and ecological context, but also from a management perspective, especially in the Galápagos and other high-value conservation areas. [ABSTRACT FROM AUTHOR]

The effects of mono- and bi-microalgal diets on shell length, organic tissue, and survival of Spondylus limbatus juveniles were tested in two separate feeding experiments. The first examined nine single species of microalgae: Chaetoceros gracilis, C. muelleri, Isochrysis aff. galbana (T-ISO), Tetraselmis chuii, T. maculata, Pavlova lutheri, Dunaliella salina, Rhodomonas sp., and Nannochloropsis sp. An extra treatment maintaining the juveniles in a long line culture was at Ayangue Bay, Province of Santa Elena, Ecuador. Single diets of P. lutheri, C. muelleri, and C. gracilis showed the best combined growth of survival performance in juveniles, and were therefore selected for the bi-algal diet experiment design with the inclusion of I. galbana T-ISO due to its recommended use in bivalve culture. A second experiment consisted in selecting the best three microalgae species that resulted from the first experiment and combined each other in binary treatments at 1:1 ratio. All bi-algal diets in combination with P. lutheri showed good result in growth (shell and biomass), yield, and survival. However, single P. lutheri mono-algal diet showed equal or better performance index than the other bi-algal combined diets, demonstrating the pertinence in using this microalga as food for S. limbatus juveniles. [ABSTRACT FROM AUTHOR]

Four geographic forms of spinner dolphin (Stenella longirostris) occur in the eastern tropical Pacific. Two of the forms are pelagic: the eastern and whitebelly, and two are coastal: the Central American and Tres Marias spinner dolphins. Of these, only the Tres Marias form lacks recognition appropriate for developing management and conservation plans. Vertical aerial photographs of 57 spinner dolphin schools taken between 1988 and 2006 were used to examine the range of coastal forms and to characterize their calving seasons. On the basis of adult body length, spinner dolphins photographed off Guerrero, Mexico, were identified as those of the Central American form, which is north of their known range, and those photographed farther north, approximately 112 km off Nayarit, Mexico, were identified as the Tres Marias form. Calving peaked from October through March, and there was evidence that calving seasons differed among geographic forms with coastal forms calving later than pelagic forms. We present the first life history parameter estimates for the coastal forms of spinner dolphins, provide additional support for recognition of the Tres Marias form, and the first evidence of the Central American form occurring north of the Gulf of Tehuantepec, Mexico. [ABSTRACT FROM AUTHOR]

Over four decades ago, a short paper demonstrated how photographs of free-swimming dolphins could be used to reveal scientific information about cetaceans. That paper, and a few others published during the same time period, illustrated a research technique that has become foundational in the field of marine mammalogy and resulted in a cascade of science. Photographs can be used to identify individuals, providing insights into movements, migrations, site fidelity, school structure and stability, and abundance. Photographs can be used to estimate group size and improve the precision of abundance estimates. Photographs can characterize reproductive output at the population level. Photographs allow for quantification of morphology, yielding insights into classification at a variety of taxonomic levels; and they provide a means to assess the condition and health of individual animals. And photographs can provide insights into behavior. The information photographs convey and their applications to cetacean research are ever-increasing. Ultimately, photographs have provided a high-quality and relatively inexpensive means to increase the knowledge base for most cetacean species in all of the oceans of the world through research conducted by scientists nations, and through of developed and developing citizen science conducted by non-scientists. [ABSTRACT FROM AUTHOR]

Mexico and Latin America need to develop a tropical marine fish farm with its native species as a strategy to diversify sustainable production options and boost food security, regional development and conservation of fishery resources. Considering the aquaculture attributes of snooks (Centropomidae) and its highest price in the national market, the objective of this work was to analyze the acclimatization of C. nigrescens, the largest species of American snooks, in freshwater and brackish water, as a first contribution in Mexico to provide the basis of its cultivation. It is a species that shows high aquaculture attributes: fast growth in fresh water, resistance to handling and a high degree of adaptability to sudden changes of salinity, in contrast to other marine fish species, which opens wide expectations for its sustainable use. [ABSTRACT FROM AUTHOR]

The complete mitogenome of Thoosa mismalolli Carballo, Cruz-Barraza & Gómez, 2004 (Tetractinellida, Thoosidae) was sequenced. This is the first complete mitogenome of the suborden Thoosina and the third Tetractinellid so far. The mitochondrial genome of T. mismalolli was assembled based on reads obtained with the Illumina HiSeq platform. The length of complete mitogenome is 19,019 bp long and contained 14 protein-coding genes and 23 tRNA, with two tRNA genes. Phylogenetic reconstruction (maximum-likelihood) based on mitogenome of Tetractinellids, supports T. mismalolli as a sister group. This result is congruent with those obtained with molecular markers (CO1, 18S, and 28S), supporting the monophyletic status of Thoosa and providing additional molecular data in favor of the suborder Thoosina. [ABSTRACT FROM AUTHOR]

Abstract The seasonal succession of species community structure, abundance and carbon biomass of five zooplankton taxa (Copepoda, Euphausiacea, Chaetognatha, Amphipoda and fish larvae) and their variability during different oceanographic conditions was investigated on the continental shelf of the central Mexican Pacific (19°N, 105°W) during a monthly time-series (1996–1998). These zooplanktonic taxa included 291 species, with maximum species richness during El Niño 1997–98, when 54 tropical oceanic species invaded the continental shelf. This typical offshore community was advected onshore by the anomalous intrusion of Subsurface Equatorial water mass which caused + 7 °C temperature anomalies. Nineteen species comprised the bulk of the abundance (91%) and biomass (87%) of the five zooplankton taxa. Multivariate statistical analysis revealed four species assemblages associated with distinct oceanographic conditions: (1) mixed water column period (upwelling; February–June, non-El Niño period) characterized by high abundance and carbon biomass of omnivorous zooplankters (copepods Subeucalanus subcrassus , Centropages furcatus , Canthocalanus pauper , Temora discaudata , and Subeucalanus subtenuis , euphausiid Euphausia distinguenda , and fish larvae Bregmaceros bathymaster); (2) stratified water column period (July–January, non-El Niño period) with low-moderate abundance and biomass of the predominant species of the first group plus the euphausiid E. lamelligera , the chaetognaths Flaccisagitta enflata and Zonosagitta bedoti , and the tropical amphipod Hyperioides sibaginis ; and (3 and 4) two highly diverse assemblages associated with El Niño-stratified conditions and post El Niño (July 1997–December 1998). These last two assemblages were distinguished by a high numerical dominance of carnivores (F. enflata , Z. bedoti , and H. sibaginis) and a pronounced decline of abundances of omnivore copepods, euphausiids, and fish larvae. Both the seasonal upwelling dynamics and the interannual-scale El Niño events shaped the tropical zooplankton community structure succession of this neritic ecosystem. The local community structure modulates the function and productivity of this ecosystem, which sustains regional fisheries and ecotouristic activities. More frequent, intense or even longer El Niño events may significantly decrease zooplanktonic carbon biomass and trophic transfer through the neritic epipelagic food web, resulting in impoverishment of the shelf biota with negative economic implications. Graphical abstract fx1 Highlights • Biomass, abundance and community structure of five zooplankton taxa were studied. • Zooplankton seasonal succession was associated with upwelling and El Niño 1997-1998. • Plankton community succession affects neritic trophic dynamic through biomass changes. [ABSTRACT FROM AUTHOR]

The first case of partial albinism registered in the Mexican Pacific by the blue lobster Panulirus inflatus is presented. The specimen was collected on the southern coast of Jalisco know as Punta "El Estrecho". It constitutes one of the few registered cases of albinism in invertebrates from the Eastern Tropical Pacific. [ABSTRACT FROM AUTHOR]

Abstract To better understand the changes in the ventilation of Oxygen Minimum Zones (OMZs) in the Eastern Tropical North Pacific (ETNP) and South Pacific (ETSP), we use an adjoint global transport model to trace the surface locations of their source waters. The transit times for surface waters to reach the OMZs are obtained for steady-state transport. For the ETNP OMZ, 26% of the water volume makes last contact with the atmosphere in the Equatorial North Pacific with mean transit time of 109 years. Mid-latitude North and South Pacific make comparable volumetric contributions (17% and 18% respectively), but have mean transit times that differ by a factor of 2 (186 and 382 years, respectively). The combined contribution of the Southern Ocean and North Atlantic accounts for 16% of the ETNP OMZ volume. The mean transit time from these remote regions is in excess of 2500 years. For the ETSP OMZ, 29% of water volume originates from the surface of the equatorial South Pacific with a mean transit time of 65 years while 36% originates from the mid-latitude South Pacific with a mean transit-time of 157 years. The relative contribution of the two regions indicates that the meridional ventilation pathway from the mid- latitudes is of equal importance as the ventilation via eastward equatorial current system. The mean transit-times computed here help clarify the timescales with which advective- diffusive processes link changes in surface ocean processes to the OMZs of the Eastern Tropical Pacific. Highlights • Waters in the ETNP and ETSP OMZs are traced back to surface sources using an adjoint modelTransit time for source waters to reach the ETNP and ETSP OMZs are obtained. • The South Pacific is equally or more important as the traditionally equatorial ventilation sources. [ABSTRACT FROM AUTHOR]

Barra de Navidad lagoon (BNL) is one of the main coastal wetlands in the coast of the State of Jalisco, Mexico. It is a Ramsar site (wetland of international importance) and has been included among the 81 mangrove sites with biological relevance and ecological rehabilitation needs in Mexico. Although fish fauna composition is well known in BNL, little evidence exists that support seasonal and spatial changes of fish assemblages' structure. The hypothesis tested in this study was that there are significant seasonal and spatial changes in BNL fish assemblages' composition which can be explained, at least partially, by changes in salinity, water temperature and sediment's granulometry. Fish assemblages were sampled monthly from October 2012 to September 2013 at four zones of BNL, using gill nets (7.62 mm stretched mesh). A sample was taken every month in a randomly selected area of each zone. Prior to each sampling operation, water salinity and temperature were measured using an YSI-30 probe. Samples of sediment were collected with a Van Veen grab sampler in three randomly selected points of each zone for granulometry and organic matter analyses. A total of 2 026 individuals belonging to 48 species were collected. Slightly more than 90 % of all caught fish belonged to nine species: Peruvian mojarra (Diapterus brevirostris), Pacific crevalle-jack (Caranx caninus), White mullet (Mugil curema), Blue sea-catfish (Ariopsis guatemalensis), Oval flounder (Syacium ovale), Pacific lined sole (Achirus mazatlanus), Yellowfin mojarra (Gerres simillimus), Pacific bumper (Chloroscombrus orqueta) and Freckled porcupinefish (Diodon holocanthus). Generalized linear models yielded significant differences among zones for the mean abundance of each of these nine species, but only in two cases seasonal differences were significant (D. brevisrostris and C. caninus). Permutational multivariate analysis of variance yielded also significant differences among zones and between seasons for the composition of the fish assemblage. Redundancy analysis using salinity, temperature, and percentage mud in sediment as environmental variables showed that fish assemblage's composition varies along two main gradients defined by mud fraction of sediments in a small spatial scale (~ 3 km) and salinity in a seasonal scale. Percentage of variation explained by canonical axes was less than 25 %, indicating that other factors could be influencing changes in assemblage composition. As most species appear as juveniles in the lagoon, fluctuations in their abundances could be linked, at least partially, with recruitment event [ABSTRACT FROM AUTHOR]

We analyzed euphausiid species composition from zooplankton samples collected during the Pacífico-ERFEN cruises in September of 2009, October of 2011 and September of 2012 in the Colombian Pacific basin. A total of 15 species (5 genera) were identified. Nine of the 15 species have been previously reported for the Colombian Pacific basin, whereas the other 6 species (Thysanopoda monacantha, Euphausia lamelligera, E. gibboides, Stylocheiron longicorne, S. maximum, and Nematoscelis tenella) were first reported in the area of study. These six species have been reported in waters adjacent to the Colombian Pacific basin (Gulf of Panama, and the Pacific coast of Ecuador and Costa Rica). [ABSTRACT FROM AUTHOR]

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Molybdenum (Mo) and (V) vanadium are under-studied elements in the ocean due to their largely conservative natures. Thus, no detailed ocean sections of these elements exist although previous reports do suggest possible anomalies in their distributions due to biological, redox, or sorptive processes. Here we present the first detailed ocean sections of dissolved and particulate Mo and V, obtained as part of the 2013 U.S. GP16 GEOTRACES East Pacific Zonal Transect (EPZT) from Peru to Tahiti. Similar to previous work, the distribution of dissolved Mo was largely conservative, while dissolved V showed a ~ 5% depletion in the upper waters. For dissolved Mo, a small number of samples showed significantly depleted concentrations which, in most cases, gradually increased with time after samples were acidified. This implies the original sample had experienced a partial change in speciation of dissolved Mo from the predominant molybdate to another, as yet, unknown form. In the oxygen deficient zone (ODZ) off the Peru margin, depleted dissolved Mo and V in a few samples corresponded with the nitrite maximum, suggesting the possible involvement of both elements in the nitrogen cycle. Particulate Mo and V enrichments in the ODZ are likely indicative of scavenging by Fe oxyhydroxides and/or biogenic particles. In near surface waters close to the Peru margin, dissolved Mo and V concentrations slightly decreased with increasing total chlorophyll a , suggesting the removal of both elements by biological uptake and/or adsorption onto biogenic particles. In contrast to previous reports that removal to reducing coastal/estuarine sediments resulted in surface water depletion of dissolved V, there is no evidence from the EPZT section that this process plays a strong role in the development of the ~ 5% dissolved V depletion in the surface ocean. Additionally, dissolved V and Mo depletions were seen in some hydrothermal plume waters above the ridge crest, likely due to adsorption onto Fe/Mn oxides and suggesting that these plume waters are a net sink for these two elements. Associations of ridge crest particulate Mo and V with the particulate Mn and Fe carrier phases suggests V was largely scavenged by Fe oxyhydroxides while Mo was likely scavenged by both Fe oxyhydroxides and Mn oxides. Away from the ridge crest, depletions of dissolved V and Mo are seen along the boundaries of the far field hydrothermal plume, though the reasons for this remain obscure. Future studies of these elements could benefit from determination of speciation as well as increased focus on margin areas. [ABSTRACT FROM AUTHOR]

Seagrass meadows are declining worldwide, mostly attributed to anthropogenic disturbances. Understanding the dynamics of these meadows is urgent in order to establish adequate management and conservation strategies. Here, we analyzed the current knowledge on the seagrass meadows in the Caribbean and Pacific coasts of Costa Rica, Central America. Current knowledge was based on literature searches, herbarium collections, informal interviews, and personal observations. We report a total of five genera and seven species for Costa Rica: Thalassia testudinum, Syringodium filiforme, Halophila decipiens, Halophila baillonis, Halodule wrightii, Halodule beaudettei, and Ruppia maritima. Six species are reported for the Caribbean, and four species for the Pacific. Thalassia testudinum, S. filiforme, and H. decipiens have only been reported for the Caribbean. Halodule beaudettei has only been reported for the Pacific coast. Halophila baillonis, H. wrightii and R. maritima have been reported for both coasts. Seagrasses were found at a total of 31 locations in Costa Rica, most from the Pacific coast; 16 of which are reported here for the first time. Seagrass meadows from both coasts are vastly different. Along the Caribbean coast, meadows are often dominated by the robust T. testudinum, they are extensive and stable, persisting for decades. In contrast, the meadows along the Pacific coast are more dynamic and are dominated by pioneer and smaller ephemeral species, such as H. baillonis and H. beaudettei. The number of studies on Costa Rican seagrasses is scarce but has been increasing over time, and mostly concern taxonomic reports and basic descriptions of the dynamics of T. testudinum meadows from the Caribbean. Research, conservation and management efforts on Costa Rican seagrass meadows would benefit from continued monitoring and research on associated fauna and flora, incorporating ecosystem resilience and services. [ABSTRACT FROM AUTHOR]

Shrimp trawling is the main deepwater fishery in Costa Rica, where Solenocera agassizii Faxon, 1893 has represented up to 30% of total shrimp landings for the Pacific coast. Despite the species' economic importance, knowledge about its biology is limited, hindering the development of an appropriate management plan for a sustainable extraction of this resource. The goals of this study were to estimate the size at onset of maturity (SOM) and to describe the reproductive dynamics of S. agassizii in order to provide information that will help to establish a minimum legal landing size and a possible fishing closure during its reproductive period. A total of 4 273 specimens (2 175 females: 2 098 males) were analyzed between January 2007 and January 2008. The overall average size was 30.8 mm CL (carapace length), with females larger (32.4 ± 5.7 mm CL) than males (29.1 ± 4.0 mm CL). SOM was estimated with a logistic regression for females (SPM: size at physiological maturity) and as the breakpoint in the CL-TL (total length) regression for both sexes (SMM: size at morphological maturity). Males reached the SMM at a larger size (32.4 mm CL) than females (30.3 mm CL), whereas the SPM for females was 37.8 mm CL. The percentages of specimens caught below the estimated SMM were 77.4% (males) and 52.1% (females), whereas 79.2% of the females were below the estimated SPM. Mature females were obtained on a monthly basis, indicating a continuous reproduction of S. agassizii with peaks between July and October. These peaks coincide with months with high precipitation and coastal upwelling. In 2013, Costa Rica prohibited the granting of new commercial shrimp trawl licenses, as well as the renewal of existing licenses. Consequently, unless the sustainability of this fishery is scientifically proven, all existing licenses will expire in 2018. The results of this study indicate that the current fishery of S. agassizii in the Pacific coast of Costa Rica is not sustainable. Hence, the assessment of mesh selectivity for this fishery - to ascertain catches were the average size caught is equal to or greater than the SOM - is urgent, as well as the establishment of a MLS of 112.6 mm TL (37.8 mm CL) and a fishing closure period in June and July. These recommendations aim to protect the spawning population and immature individuals of S. agassizii. Nevertheless, it is recommended to study the viability of employing alternative fishing gears to reduce the percentage of immature individuals captured and to avoid an overexploitation of the resource. [ABSTRACT FROM AUTHOR]

Abstract: Models and observations disagree regarding sea surface temperature (SST) trends in the eastern tropical Pacific. We present a new Sr/Ca‐SST record that spans 1940–2010 from two Wolf Island corals (northern Galápagos). Trend analysis of the Wolf record shows significant warming on multiple timescales, which is also present in several other records and gridded instrumental products. Together, these data sets suggest that most of the eastern tropical Pacific has warmed over the twentieth century. In contrast, recent decades have been characterized by warming during boreal spring and summer (especially north of the equator), and subtropical cooling during boreal fall and winter (especially south of the equator). These SST trends are consistent with the effects of radiative forcing, mitigated by cooling due to wind forcing during boreal winter, as well as intensified upwelling and a strengthened Equatorial Undercurrent. [ABSTRACT FROM AUTHOR]

Stable isotope analysis of tissues with different turnover rates allows for a broader temporal view of a species' feeding habits. Epidermal mucus is a rapid to medium turnover 'tissue' in teleost fish, but its use in elasmobranch dietary studies is unknown. In the present study, we conducted stable isotope analysis onmucus andmuscle fromthe giantmanta ray Manta birostris. Mucus δ13C values were depleted and closer to surface zooplankton δ13C values compared with muscle, whereas there was no significant difference in δ15N values between these two tissue types. Using diet tissue discrimination factors from the literature, there was no significant difference in the expected prey profile between muscle and epidermal mucus. However, a broader range in δ13C values of expected prey was shown for mucus compared with muscle. The results suggest that if M. birostris mucus is indicative of recent dietary intake, resource use during aggregative behaviour off Ecuador is broader, but with no obvious resource switching. The present study is the first example of using bulk stable isotope analysis to evaluate mucus to investigate feeding ecology in elasmobranchs. However, the time course for the change in mucus isotope signature still needs to be determined through controlled feeding studies in an aquarium setting. [ABSTRACT FROM AUTHOR]

The epibionts of marine megafauna can serve as valuable indicators of the host's health or behaviour; however, only a few studies have attempted to determine how and why epibiont communities vary between host individuals, populations, or even species. Further complicating efforts to compare epibiont communities of marine megafaunas is that measures of epibiont abundance and diversity may be influenced by the sampling methods and timing of the assessment. Here, we examined how host gender, geographic location, and sampling year affect measures of epibiont community structure in olive ridley sea turtles, Lepidochelys olivacea , in the East Pacific Ocean. To achieve this, we identified, enumerated, and then statistically compared the epibiont communities of (1) nesting female turtles sampled over different nesting seasons, (2) female turtles sampled on nesting beaches and at sea, and (3) female and male turtles, both sampled at sea. We did not discover statistically significant differences between the epibiont communities of nesting female turtles sampled on different years nor between females sampled on nesting beaches and at sea. However, we did observe a statistically significant difference between the epibiont communities of female and male turtles. Thus, we conclude that while sampling epibionts from nesting sea turtles may be an accurately and more logistically straight-forward method than sampling turtle at sea, it should not be assumed that epibiont communities of male and female hosts are identical. We also suggest that knowledge of the factors that drive intra-specific variation in the epibiont communities of marine megafauna, be it biological or methodological factors, is necessary before broader-scale meta-analyses are made to determine spatial and temporal patterns in the distribution of epibiont communities worldwide. [ABSTRACT FROM AUTHOR]

Sea turtles host a diverse array of epibionts, yet it is not well understood what factors influence epibiont community composition. To test whether epibiont communities of sea turtles are influenced by the hosts’ nesting or foraging habitats, we characterized the epibiota of leatherback, olive ridley and green turtles nesting at a single location on the Pacific coast of Costa Rica. We also compared the epibiota of these turtles to conspecific populations nesting elsewhere in the East Pacific. If epibiont communities are influenced by nesting habitats, we predicted that sympatrically nesting turtles would have comparable epibiont taxa. Alternatively, if epibiont communities are influenced by foraging habitats, we predicted the diversity of epibiont taxa should reflect the type and diversity of the hosts’ foraging habitats. We identified 18 epibiont taxa from 18 leatherback, 19 olive ridley and six green turtles. Epibiont diversity was low on leatherbacks (four taxa), but higher for olive ridley and green turtles (12 and nine epibiont taxa respectively). The epibiont communities of olive ridley and green turtles were not statistically different, but both were different from leatherbacks. In addition, conspecific sea turtles from other nesting locations hosted more similar epibiont communities than sympatrically nesting, non-conspecifics. We conclude that epibiont diversity of nesting sea turtles is partially linked to the diversity of their foraging habitats. We also conclude that the surface properties of the skin and carapace of these turtles may contribute to the uniqueness of leatherback turtle epibiont communities and the similarities between olive ridley and green turtle epibiont communities. [ABSTRACT FROM PUBLISHER]

Isla del Coco, Costa Rica, is one of the five groups of oceanic islands of the Eastern Tropical Pacific (ETP), and is considered one of the most diverse. Since the mid-19th century, it has been the target of a number of scientific research expeditions that have produced specimen collections which are housed in natural history museums around the world. The fish assemblage of Isla del Coco is considered one of the most speciose and best documented group of marine organisms of the island. Despite this, recent work has resulted in a need to update the checklist for this important group. We performed a completeness analysis of the ichthyofauna of Isla del Coco based on scientific publications and reports of expeditions, specimens in foreign and national collections, and field surveys. We confirmed the presence of 514 species of marine fishes, representing an increase of approximately 23 % compared to what was previously reported. From a habitat perspective, 58 % of this assemblage is typically reef fishes, while the remaining 42 % are deep-water, and pelagic species. The average expected reef fish species richness is 318.2 ± 7.3, suggesting that the local inventory represents 93.7 % of the expected total richness. Our updated list and greater number of species has particular relevance to the conservation efforts at Isla del Coco, since current conservation efforts are protecting at least 50 % of ETP fish species and about 40 % of Costa Rica's Pacific fish species. [ABSTRACT FROM AUTHOR]

Deep-water habitats are among the least studied but most vulnerable environments. By-catch data from deep-water fisheries in Latin America are limited, and detailed reports on associated molluscs are scarce. This study provides information on deep-water shelled molluscs collected between 2010 and 2011 by commercial shrimp trawling fisheries along the Pacific coast of Costa Rica at depths from 112 to 271 m. Twenty-six species were identified, 23 gastropods and three bivalves. Our data extend the depth range of 14 species, andHomalopomacf. grippiiis reported for the first time for Costa Rica. The most common species were the gastropodsFusinus spectrum,Polystira nobilisandSolenosteira gatesi. Only one species (Sinum debile) was captured below 250 m. The catch of molluscs per unit effort was influenced by depth, but not by seasonality or geographic area. It is speculated that these long-lasting bottom-trawling activities have caused negative effects on species diversity and mollusc biomass. Nevertheless, a monitoring program is recommended to assess possible impacts of this type of fishery on mollusc diversity and biomass. [ABSTRACT FROM PUBLISHER]

Although the wider Eastern Tropical Pacific has been systematically surveyed during summer/fall, relatively little effort has focused on shelf and slope waters of Nicaragua and Costa Rica. Such data are useful for establishing baseline information and assessing potential changes in cetacean occurrence and distribution relative to natural (e.g., El Niño-Southern Oscillation, climate change) and anthropogenic factors. A visualacoustic survey for cetaceans occurred as part of a monitoring and mitigation program during an academic geophysical seismic study off Nicaragua and Costa Rica, during November-December 2004. Approximately 2 067 cetaceans representing at least seven species were seen in 75 groups during 373 h (3 416 km) of daytime observations from the seismic research vessel (R/V) Maurice Ewing. The humpback whale (Megaptera novaeangliae) and the pantropical spotted dolphin (Stenella attenuata) were the most frequently sighted species (30 % of all groups sighted); both were seen in shelf waters < 100 m deep and in slope waters. The bottlenose dolphin (Tursiops truncatus; 10 % of sightings) was the third most frequently sighted species and was only seen in water > 100 m deep. In addition, sightings were made of spinner dolphins (S. longirostris), short-beaked common dolphins (Delphinus delphis), Risso’s dolphins (Grampus griseus), short-finned pilot whales (Globicephala macrorhynchus), and unidentified dolphins and whales. Unconfirmed sightings of a minke whale (Balaenoptera acutorostrata) and a pod of false killer whales (Pseudorca crassidens) were also recorded. An additional six groups of dolphins (50 % confirmed to species, all pantropical spotted dolphins) were made during 187 h (1 549 km) of observation effort during darkness, two of which were detected within 30 m of the vessel bow using a night vision device. A total of 217 cetacean detections occurred during 633 h of passive acoustic monitoring. A small concentration of 12 humpback whales was seen in eight groups, and two humpbacks were recorded singing in the Gulf of Fonseca on 9 December 2004. To our knowledge, such concentrations of humpback whales, particularly singing humpbacks, have not been previously reported in this specific area. In addition, a humpback mother-calf pair, likely from the Northern Hemisphere population, was seen off Northern Costa Rica on 25 November 2004. Although cetacean sighting rates were significantly different during seismic and non-seismic periods even when corrected for differential detection probability related to sea conditions, our survey results do provide information to address previous data gaps on cetacean occurrence in shelf and slope waters off the Pacific coast of Central America during late fall. [ABSTRACT FROM AUTHOR]

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Background: The caprellid fauna from different localities along the Mexican Pacific coast: Sinaloa (3), Nayarit (15), Jalisco (9) and Colima (1) are presented herein. Methods: A total of 1,093 specimens associated with diverse substrates (octocorals, hydroids, algae, coral rubble and sponge) were recorded. Results: Eight species in four genera were identified: Aciconula acanthosoma Chess 1989; Caprella mendax Mayer 1903; Caprella pitu Sánchez-Moyano, García-Ascencio and Guerra-García 2014; Caprella suprapiscis Galván-Villa and Ayón-Parente 2015; Paracaprella carballoi Sánchez-Moyano, García-Ascencio and Guerra-García 2014; Paracaprella isabelae Sánchez-Moyano, García-Ascencio and Guerra-García 2014; Paracaprella pusilla Mayer 1890; and Liropus isabelensis Sánchez-Moyano, García-Ascencio and Guerra-García 2014. Conclusions: The new records increase the known species richness in the region at local level, including extensions of the known ranges for all the species. These results highlight the need for a large scale survey along the Mexican Pacific coast, along with a more thorough sampling on a large number of substrata, in order to increase the knowledge of caprellid diversity in the area. [ABSTRACT FROM AUTHOR]

The coral reefs of the Eastern Tropical Pacific (ETP) are some of the most geographically isolated of the world. A key to understanding their long-term persistence and population recovery via dispersal (i.e. population connectivity), is knowing when the corals spawn in the region. To this end, we reviewed and synthesized the literature on the reproductive phenology of corals (month of spawning) and their dispersal-related characteristics to infer the potential impact on the region's functional connectivity. We classified the region into four thermal regimes based on long-term mean sea surface temperature (SST) data: Tropical Upwelling, Thermally Stable, Equatorial Upwelling, and Seasonal. Each regime's unique spawning seasonality was then explored by quantifying the linear dependence between the number of observed spawning events and SST. Finally, the potential impact of this unique regional mismatch in spawning was illustrated using a biophysical larval dispersal model. We found spawning occurs throughout the year in the Upwelling and Thermally Stable regimes (showing low or no linear dependence with SST); whereas spawning had a strong seasonal signal in the Equatorial Upwelling and Seasonal regimes, occurring primarily in the warm months. Considering the region's mismatch in spawning phenologies, and unique dispersal traits, the simulations of coral larval dispersal across the ETP result in infrequently realized connectivity between ecoregions, low local retention and high self-recruitment, that combined with low recruitment densities in the field indicates more vulnerable populations to disturbance than previously appreciated. The strong relationship between spawning phenology and SST in some regimes suggests a greater susceptibility of these coral assemblages to extreme El Ni~no and La Ni~na events and future ocean warming. [ABSTRACT FROM AUTHOR]

The failure to achieve fisheries management objectives has been broadly discussed in international meetings. Measuring the effects of fishery regulations is difficult due to the lack of detailed information. The yellowfin tuna fishery in the eastern Pacific Ocean offers an opportunity to evaluate the fishers' responses to temporal regulations. We used data from observers on-board Mexican purse-seine fleet, which is the main fleet fishing on dolphin-associated tuna schools. In 2002, the Inter-American Tropical Tuna Commission implemented a closed season to reduce fishing effort for this fishery. For the period 1992-2008, we analysed three fishery indicators using generalized estimating equations to evaluate the fishers' response to the closure. We found that purse-seiners decreased their time spent in port, increased their fishing sets, and maintained their proportion of successful fishing sets. Our results highlight the relevance of accounting for the fisher behaviour to understand fisheries dynamics when establishing management regulations. [ABSTRACT FROM AUTHOR]

We provide the first estimations of calanoid copepod egg production rates (EPR) in the Eastern Tropical Pacific over an annual cycle (January–December 2011). Gravid females were collected twice monthly and incubated for 12 h without food to estimate EPR, weight-specific fecundity (Gf), spawning success (SS, percentage of females to spawn out of the total species incubated per month and season) and egg hatching success (EHS). This study reports the average EPR of 10 species and the monthly EPR and Gf of four planktonic calanoid copepods ( Centropages furcatus , Temora discaudata , Pontellina sobrina , and Nannocalanus minor ) that spawned with enough frequency to infer their seasonal reproductive patterns. These species showed distinct seasonal reproductive strategies. Most copepod species spawned sporadically with large EPR variability, while three copepod species reproduced throughout the year ( C. furcatus , T. discaudata and P. sobrina ) and N. minor spawned only during the mixed period (Feb–May). The four species had relatively similar average EPR ( C. furcatus 16, T. discaudata 18, P. sobrina 13, and N. minor 12 eggs fem −1 day −1 ). These are the first EPR estimations of P. sobrina and its previously known reproductive period is expanded. A Canonical Correspondence Analysis (CCA) was used to analyze EPR and species abundance of all calanoid copepods (40 spp.) collected throughout the time series in relation to temperature, salinity, mixed layer depth (MLD), dissolved oxygen, and chlorophyll a (Chl-a) concentrations to identify the variables that best explained the copepod abundance variability. Temperature, Chl-a, and salinity had the strongest effect on the biological variables, linked to seasonal and episodic upwelling-downwelling processes in the surveyed area. As a result of moderate upwelling events and seasonal variation of environmental conditions, it appears relatively few species are capable of maintaining continuous reproduction under the relatively higher temperatures and strong fluctuations of food availability that exist in this coastal habitat of the Eastern Tropical Pacific. [ABSTRACT FROM AUTHOR]

Despite the ecological importance of decapod crustaceans in energy transfer in marine ecosystems, little is known on their distribution below oxygen minimum zones (OMZs). To understand the spatio-temporal dynamics of benthic and benthopelagic decapod crustaceans living below the OMZ cores, four seasonal oceanographic and sledge surveys were performed in the south-east Gulf of California at depths between 730 and 2250 m. Multivariate analyses indicate the existence of three major depth-related assemblages at: 800-1000, 1000-1200 and .1200 m (mean trawl depth). Benthic detritivores dominated between 800 and 1000 m and benthopelagic (i.e. swimming) predators dominated deeper, where dissolved oxygen (DO) values were higher. Assemblages comprised the same species throughout the year, but aggregations of smaller organisms were observed in June. DO significantly controlled the distribution of decapod crustaceans, likely through physiological exclusion of swimming species from hypoxic waters. Besides, the combined effects of DO and temperature contributed to defining the depth ranges occupied by each species. Food derived from surface-water production modulated changes in community parameters with different time lags in the different depthrelated assemblages. These findings demonstrate the vulnerability of bathyal communities to the global pattern of OMZ expansion. [ABSTRACT FROM AUTHOR]

The present study analyses whale shark Rhincodon typus stranding in the Gulf of California, Mexico, reported by the public, scientists, authorities and artisanal fishermen. A total of 14 strandings were documented during the period 2001–2018. The total length of R. typus ranged from 350–1,102 cm, with a sex ratio of 3.5:1 (males: females). This study highlights potential stranding areas, the need for better stranding protocols to assist R. typus recovery and the importance of samples from dead animals for scientific research. [ABSTRACT FROM AUTHOR]

The isolated Isla del Coco experiences periodic, extreme disturbances which devastate coral reefs surrounding the island. Scleractinian corals build the physical structure of the reef therefore ecosystem recovery relies on coral species recovery. Coral recruits can be of sexual or asexual origin, and the relative success of the two recruit types influences the speed and spread of recovery processes. Here we focus on the massive coral, Porites lobata, because it is the main reef-builder around Isla del Coco to describe the relative contribution of asexual and sexual recruits to population maintenance. P. lobata samples were collected using a spatially explicit random sampling design in three plots at Isla del Coco: Punta Ulloa (n=17), Bahía Weston (n=20) and Punta María (n=20) and samples were genotyped with 11 microsatellite markers. Additional sampling was conducted at three “coastal” sites near the Costa Rican mainland (Isla del Caño Biological Reserve): Caño1 (n=8), Caño2 (n=10), Caño5 (n=11) to compare the contributions of asexual and sexual recruits at Isla del Coco sites to coastal sites. Isla del Coco sites were characterized by small colony size (>60% of colonies Los ambientes marinos del Parque Nacional Isla del Coco experimentan perturbaciones extremas periódicamente como por ejemplo El Niño-Oscilación del Sur (ENOS) que han devastado las comunidades coralinas. La cobertura coralino se redujo drásticamente durante El Niño de 1982-83. Los corales escleractinios construyen la estructura física de los arrecifes así que la recuperación de estos ecosistemas depende de que los corales se recuperen. Los corales pueden reproducirse sexual y asexualmente, y el éxito relativo de cada forma de reproducción va a guiar el proceso de recuperación con implicaciones potenciales a la diversidad de las comunidades asociadas. En la mayoría de los arrecifes alrededor de la Isla del Coco, el coral masivo, Porites lobata, es la especie constructora predominante. Si la diversidad genotípica (clonal) de esta especie es alta, la diversidad de individuos va a ser más alta resultando en mayor resilencia frente a condiciones ambientales extremas. Alternativamente, una diversidad genotípica baja es indicativo de una estrategia reproductiva asexual posiblemente resultando en el mantenimiento de genotipos bien adaptados aunque la población decline. Aquí, usamos 11 marcadores microsatélite para investigar la contribución relativa de la reproducción sexual o asexual en la recuperación de los arrecifes en el Parque Nacional Isla del Coco. En la Isla del Coco se recolectaron muestras en: Punta Ulloa (n=17), Bahía Weston (n=20) y Punta María (n=20), y para comparar, se recolectaron muestras en localidades cerca de o en la costa continental de Costa Rica; Reserva Biológica Isla del Caño: Caño1 (n=8), Caño2 (n=10) y Caño5 (n=11), y Tres Hermanas, Parque Nacional Marino Ballena (n=4), utilizando un diseño de muestreo espacialmente explícito. Las colonias de la Isla del Coco son generalmente pequeñas (>60% de las colonias 2.5m2) y por lo tanto, potencialmente colonias bien adaptadas, puede aumentar las resistencia y resilencia de los sistemas.

Los anfípodos hiperídeos son uno de los grupos de crustáceos pelágicos más frecuentemente encontrados y están entre los más diversos del zooplancton marino. Para determinar la composición de especies de anfípodos hipéridos que habitan las aguas alrededor del Parque Nacional Isla del Coco, Costa Rica, se analizaron 12 muestras de zooplancton. Estas fueron recolectadas mediante arrastres verticales y horizontales con una red de plancton con mallas de 200 y 500 micras y 49cm de diámetro en la boca. Se encontró un total de 22 especies pertenecientes a 17 géneros y 12 familias. Se presenta el listado faunístico de este grupo junto con datos acerca de su taxonomía, su distribución en el área de estudio y su distribución general. La mayor parte de las especies registradas en esta zona han sido reportadas en estudios previos referentes a la región del Pacífico Tropical Oriental y en particular en aguas oceánicas de Costa Rica. Encontramos ocho especies que representan nuevos registros para aguas del Pacífico costarricense, lo que incrementa en un 26% (a 38) el número de especies de hipéridos conocidos en Costa Rica. Las especies más frecuentes fueron Lestrigonus shoemakeri, L. bengalensis, Hyperioides sibaginis y Phronimosis spinifera. Se espera que muestreos adicionales tanto de aguas superficiales como profundas expandan el conocimiento de la diversidad del grupo en esta área protegida.Hyperiid amphipods are one of the most frequently encountered pelagic crustaceans and among the most diverse marine zooplankters. To determine the species composition of the hyperiid amphipods dwelling in the waters around Isla del Coco National Park, Pacific Costa Rica, we analyzad 12 zooplankton samples, collected by vertical and horizontals tows with plankton net with mesh sizes of 200 and 500 microns and 49cm mouth diameter. We recorded a total of 22 species belonging to 17 genera and 12 families. A faunistic list of this group is provided together with data on their taxonomy and their distribution both in the surveyed area and in general. Most of the species recorded in this zone have been reported in previous surveys in the Eastern Tropical Pacific region and particularly in oceanic waters of Costa Rica. We found eight species representing new records for Costa Rican waters, thus increasing by 26% (to 38) the number of hyperiid species known from Costa Rica. The most frequent species were Lestrigonus shoemakeri, L. bengalensis, Hyperiodes sibaginis, and Phronimopsis spinifera. We expect that additional samplings both from surface and deep waters will expand the knowledge of the diversity of the group in this important protected area.

Se recolectaron de distintas fuentes documentales los nombres de setenta y seis topónimos correspondientes a los principales accidentes topográficos del Parque Nacional Isla del Coco, Costa Rica. Estos se pueden agrupar en cuatro grupos principales, como son aquellos pertenecientes a las visitas de navegantes británicos, la vida republicana en Costa Rica y aquellos de la flora y fauna, tanto terrestre como marina. La metodología empleada ha permitido identificar setenta y uno de estos topónimos. Conceptualmente, el dinamismo del abordaje metodológico y la divulgación de sus resultados sugieren tener implícito un proceso de retroalimentación.Many names have been used for the different places of Isla del Coco, and some have changed over time. Studying different historic sources, seventy-six names of the main topographic features were collected for Isla del Coco National Park, Costa Rica. These names could be grouped in four main categories: those associated with the British traveler’s visitations, the ones related with the republican period of Costa Rica and those linked with the island’s terrestrial and marine flora and fauna. The methodology used allowed the proper documentation of seventy-one names. This methodology and the publication of this dictionary intend to generate a feedback regarding the naming of topographic characters of Isla del Coco.

Corals display different growth forms as an adaptive response to both local and global environmental conditions. Despite the importance of morphologic variability on corals, growth and calcification rates of different coral morphotypes have been poorly recorded in the Eastern Pacific. The purpose of this study was to compare annual extension rate (cm yr-1), skeletal density (g cm-3), calcification rate (g cm-2 yr-1) and tissue thickness (mm) of males and females colonies in three different morphotypes of the common reef-building coral Porites lobata; columnar, massive, and free-living (corallith) forms. The results show significant differences in all 4-growth parameters between morphotypes over a 6-year interval, and also differences between males and females in most morphotypes. Massive colonies presented 15-33% faster annual rates compared with columnar and free-living. Male colonies showed 30-40% faster annual rates than females for both columnar and corallith morphologies. These data exhibit the extensive plasticity of this species and highlight the fact that each morphotype x gender group produced a different physiological response to environmental conditions. Therefore, these information reveal that P. lobata from the Eastern Tropical Pacific develops different morphologies to allow it to maintain coral species population, characteristics that enhance the species possibility to further its distribution across the reef-framework

Sea urchins are important grazers and influence reef development in the Eastern Tropical Pacific (ETP). Diadema mexicanum and Eucidaris thouarsii are the most important sea urchins on the Ecuadorian coastal reefs. This study provided a trophic scenario for these two species of echinoids in the coral-rocky reef bottoms of the Ecuadorian coast, using stable isotopes. We evaluated the relative proportion of algal resources assimilated, and trophic niche of the two sea urchins in the most southern coral-rocky reefs of the ETP in two sites with different disturbance level. Bayesian models were used to estimate the contribution of algal sources, niche breadth, and trophic overlap between the two species. The sea urchins behaved as opportunistic feeders, although they showed differential resource assimilation. Eucidaris thouarsii is the dominant species in disturbed environments; likewise, their niche amplitude was broader than that of D. mexicanum when conditions were not optimal. However, there was no niche overlap between the species. The Stable Isotope Analysis in R (SIAR) indicated that both sea urchins shared limiting resources in the disturbed area, mainly Dictyota spp. (contributions of up to 85% for D. mexicanum and up to 75% for E. thouarsii). The Stable Isotope Bayesian Ellipses in R (SIBER) analysis results indicated less interspecific competition in the undisturbed site. Our results suggested a trophic niche partitioning between sympatric sea urchin species in coastal areas of the ETP, but the limitation of resources could lead to trophic overlap and stronger habitat degradation.

Mangrove forests are abundant and important coastal marine ecosystems that are being impacted by human activity in Costa Rica. There are two mangrove stands (Panama and Iguanita) in Bahia Culebra, Guanacaste, North Pacific coast of Costa Rica. Their forest structure was determined with the Point-Centered Quarter Method (PCQM) during the dry season (December 2007-March 2008). Eleven transects were established at Panama mangrove, with a total of 52 points and 208 quadrats. Two transects were established at Iguanita with a total of 16 points and 62 quadrats given access difficulty. Mapping of both stands was done with two georeferenced MASTER CARTA 2005 images. Images were digitized to 1:5000 scale using the following categories: mangrove forest, low density mangrove, no mangrove, transition to dry forest, sand and water. In the area studied at Panama was 13.7ha, and 40.8ha for Iguanita. Panama is mostly composed of dense mangrove forest (51% of total study area) and dry forest species (35% of total study area). A small area (2%) had dry soil and scarce mangrove trees and the remaining 12% corresponds to water, sand and other areas without vegetation. At Iguanita, 84% was dense mangrove, 5% scarce mangrove trees and the remaining 10% corresponds to water, sand and other areas without vegetation. Five mangrove species were encountered at Panama (Avicennia germinans, Avicennia bicolor, Conocarpus erectus, Laguncularia racemosa, and Rhizophora mangle), and three at Iguanita (A. germinans, L. racemosa, and R. mangle). Species zonation was similar at both stands; with Rhizophora near water channels and inundated areas, Avicennia frequent in drier areas, and Laguncularia (both stands) and Conocarpus (only Panama) more frequent near fresh water input. Densities at both stands (Iguanita= 67.2 and Panama= 8.4 stems/0.1 ha) were lower than reported for the north Pacific of Costa Rica. Complexity index was higher at Iguanita (CI= 86.5) with R. mangle dominance, than Panama (CI= 1.1) with A. germinans dominance. While both stands are in Bahia Culebra, structurally they are very different and seem to be under two different hydrodynamic contexts. Sea level rise related to global climate change might impact both mangrove stands as they would not be able to migrate further inland (given land elevation at the back of Iguanita, and a paved road at Panama). Given the socio-economic and ecological importance of mangrove habitats, further study and continued conservation efforts of Costa Rican mangroves are needed.Los manglares son abundantes e importantes ecosistemas marino-costeros en Costa Rica pero están siendo afectados por la actividad humana. Se analizo la estructura y cobertura de ambos manglares presentes en Bahía Culebra (Panamá e Iguanita), Guanacaste, Pacifico norte de Costa Rica. Se utilizo el PCQM para estructura durante la época seca entre diciembre 2007 y marzo 2008. Se utilizaron dos imágenes MASTER CARTA 2005 georreferenciadas para mapeo. El área aproximada de bosque de manglar en Panamá fue de 13.7ha; y de 40.8ha en Iguanita. Panamá contiene 51% de manglar denso en el área de estudio, 35% bosque seco, 2% sin vegetación y 12% de arena o agua. En Iguanita el 84% del área corresponde a manglar denso, 5% manglar de baja densidad y 10% sin cobertura vegetal o era arena o agua. Se hallaron cinco especies de manglar en Panamá (Avicennia germinans, Avicennia bicolor, Conocarpus erectus, Laguncularia racemosa y Rhizophora mangle); y tres en Iguanita (A. germinans, L. racemosa y R. mangle). En general, la presencia de las especies de manglar siguió un patrón similar en ambos manglares. La densidad total fue menor que en manglares cercanos; y Panamá (8.4tallos/0.1ha) mucho menor que Iguanita (67.2tallos/0.1 ha). El Índice de Complejidad (IC) fue mucho mayor en Iguanita (IC= 86.5), con dominancia de R. mangle, que en Panamá (IC= 1.1), con dominancia marcada de A. germinans. Estructuralmente ambos manglares son muy distintos entre sí y parecen encontrarse en contextos hidrodinámicos diferentes.

The 1982-83 El Niño event produced a high coral mortality (50-90%) in several localities in the Eastern Tropical Pacific, which resulted in an outbreak of the sea urchin populations of Diadema mexicanum A. Agassiz, 1863 in some reefs, leading to an increase in coral framework bioerosion. In Costa Rica, El Niño impact varied among three of the most important coral reefs localities, being higher in Cocos Island, moderate in Caño Island, and lower in Culebra Bay; D. mexicanum densities followed the same pattern. To understand the historic role of this sea urchin on the balance between bioerosion and bioacretion, we made a reconstruction of bioerosion impact based on current patterns of carbonate ingestion by the sea urchins, growth rates and skeletal density of the main coral builders, and historical information of sea urchin population density and coral cover. The reconstruction model varied depending on locality. At Cocos Island, the effect on the reef carbonate budget ranged from negative to positive, improving coral recruitment and the recovery of the reef. At Caño Island, there was no apparent effect. In Culebra Bay, the effects ranged from a positive-neutral effect to a negative one, the latter possibly associated with an increase of eutrophic conditions that facilitated bioerosion of the coral framework. The importance of this sea urchin in reef dynamics varies with amount of reef protection, overfishing, and coastal management, and it has a large influence on the carbonate balances of the Pacific Costa Rican coral reefs.El fenómeno de El Niño de 1982-83 produjo una alta mortalidad coralina (50-90%) en varias localidades del Pacífico Tropical Oriental, lo que en algunos arrecifes trajo como consecuencia una explosión en la poblaciones de erizos de mar, Diadema mexicanum, y por consiguiente un aumento en la bioerosión del basamento coralino. En Costa Rica, el impacto fue diferencial en tres localidades arrecifales, siendo mayor en la Isla del Coco, intermedio en la Isla del Caño, y menor en Bahía Culebra, con similares patrones en la presencia del erizo D. mexicanum. Con el fin de poder entender el papel histórico que desempeña este erizo de mar en el balance entre bioerosión y bioacreción, se reconstruyó el impacto bioerosivo basándose en patrones actuales de ingestión de carbonatos por parte del erizo, tasas de crecimiento y densidad del esqueleto coralino, y datos históricos de densidad poblacional del erizo y cobertura coralina. Los resultados de las reconstrucciones variaron dependiendo de la localidad. En la Isla del Coco, el efecto de los erizos de mar varío de un efecto negativo sobre el balance arrecifal de carbonatos a un efecto positivo, favoreciendo el reclutamiento coralino y la recuperación del arrecife. En la Isla del Caño, Diadema presentó un efecto neutro, al no tener una participación preponderante en el balance de carbonatos de esta isla. Mientras, que en Bahía Culebra, los efectos de los erizos de mar pasaron de tener un efecto positivo-neutro, a uno negativo, posiblemente asociado a un incremento en condiciones eutróficas de la bahía que están favoreciendo un incremento en la bioerosión del basamento coralino. El valor de este erizo en la dinámica arrecifal y su relación con la protección, sobrepesca, y manejo costero, posee una gran influencia en el balance de carbonatos en los arrecifes coralinos del Pacífico de Costa Rica.