Tropical Pacific Coast Research Articles

Massive offerings of marine fish at Salango, coastal Ecuador, during the Middle Guangala phase (AD 300–600)

The Ecuadorian site of Salango, with its 5500 years of pre-Columbian history, is of fundamental interest for understanding the relationships between people and the sea on the tropical Pacific coast of South America. In 2015, thousands of fish remains were found in foundational offering deposits of a perimeter wall built to protect a sanctuary of the Middle Guangala phase (AD 300–600). Approximately 3300 bones have been identified, and these represent the remains of 337 individuals belonging to 49 different species. The assemblage is largely dominated by pelagic species, particularly scombrids weighing 2–3 kg. The presence of dolphinfish, a taxon that has not been reported previously in the archaeological record of Salango, supports the hypothesis that fishing was mainly conducted offshore by boat. The preservation in situ of numerous anatomical connections and the large number of remains found virtually intact suggest that these fish were deposited whole. We suggest that these deposits were designed to represent the specific marine environment being exploited from Salango and, more broadly, the sea itself. In this respect, Salango presents an unusual manifestation of pre-Columbian sea-oriented ritual practice so far unique on the Ecuadorian coast.

Variation of the diet of the sea urchin (Diadema mexicanum (Diadematoida: Diadematidae)) according to its size in the Eastern Tropical Pacific

Introduction: The sea urchin Diadema mexicanum, due to its bioerosion activity, is considered of ecological importance. This phenomenon could negatively or positively affect coral reef ecosystems. The bioerosion process varies according to the abundance and size of the sea urchin.
 Objective: Juvenile organisms possess different metabolic needs compared to adults, so knowing their stomach content according to size allows us to quantify the selection of substrate bioeroded.
 Methods: To determine this, D. mexicanum individuals were collected in 12 sites from January 2009 to September 2010 along the Eastern Tropical Pacific coast. The stomach content was categorized in Carbonated Fraction (CF), Non-Carbonated Fraction (NCF), and Organic Matter (OM). Stomach content was analyzed according to a) juvenile (< 2.5 cm) or adult (> 2.5 cm) stage and b) locality.
 Results: Juveniles presented the following stomach content average percentages: 20.7 % OM, 12 % NCF and 67.9 % CF; and adults: 11.4 % OM, 14.8 % NCF and 73.8 % CF. Based on a Wilcoxon test and a Kendall linear regression, the following results were obtained. The carbonated fraction in the stomach increased by 0.47 units on average for every cm of growth (p < 0.05). OM consumed by D. mexicanum increases only 0.05 units for every cm of growth (p < 0.05). We found a difference of stomach content depending on the site (p < 0.05) and life stage (p < 0.05). Localities like Huatulco and Coco presented significant differences that could be related to local oceanographic conditions.
 Conclusions: We relate these changes of the stomach fractions to the necessity of the juvenile sea urchins for nutrients to maintain their growth. The amount of OM is crucial for the development of early stages, meaning that there is a difference in substrate selection associated with growth.

Description of a new species of Liropus (Crustacea, Amphipoda) from Puerto Vallarta, Pacific coast of Mexico.

A new species of the genus Liropus Mayer, 1920 (Amphipoda, Caprellidae) is described from the Mexican Tropical Pacific coast. Liropus alarconi n. sp. is described on the basis of four specimens collected in association with the tropical marine sponge Trikentrion helium Dickinson, 1945, near to coralline patches, between 2330 m depth. Liropus alarconi n. sp. can be distinguished from its congeners for the following characters: pereonites 25 each with one dorsodistal projection and pereonite 3 with a mediolateral projection.

Interactions between small-scale fisheries and marine mammals from the perspective of fishers in the Mexican tropical pacific coast

The increase in fishing effort and the expansion of the fishing grounds of small-scale fisheries increase the interactions with marine mammals globally. Such interactions are poorly understood since data is difficult to obtain. The aim of this study is to infer the interactions between small-scale fisheries and marine mammals, based on the fisher’s perspective. We used the southern coast of Chiapas, Mexico as the location for the model. A total of 56 interviews and eight fishery trips were conducted in three fishing communities. Fishing vessels are 7 m long with an outboard engine with 58.9% of fishers using gillnets and 21.4% using longlines. Fishers were able to identify three marine mammal species in their fishing grounds: Tursiops truncatus, Stenella longirostris, and Stenella attenuata graffmani. However, based on photographs, fishers identified seven additional species. Tursiops truncatus interacts negatively with their fishing activities by stealing fish, ripping nets, interfering during sets, and stealing bait from longlines, which fosters a negative perception among fishers. Despite this, fishers implement low-impact mitigation measures. A Canonical Correspondence Analysis revealed the adverse impact of the common bottlenose dolphin on Scomberomorus sierra fishing with gillnets at the coastal zone. The presence of S. longirostris centroamericana and S. attenuata graffmani has a positive impact on the fishery because are indicators of fish schools. The perception of fishers is key to understanding the complex relationship between fisheries and marine mammals, and can help set the basis for management and conservation programs in areas where such interactions are intense.

A new genus and seven new species of chrysopetalids (Annelida, Chrysopetalidae) from the Tropical Eastern Pacific.

Chrysopetalids annelids have been little studied in the Tropical Eastern Pacific (TEP), with only 24 species recorded in the region. Most records are from northwestern Mexico and Costa Rica, leaving many sites along the Tropical Pacific coast of America unexplored. Furthermore, there are species recorded and described from the region with problems in their status, including questionable records, modest illustrations or descriptions, and lost type material. This paper aims to improve the knowledge of this family in the TEP. Almost 290 specimens were revised, provided from five scientific collections, covering 51 sites along the TEP and nearby. Two subfamilies: Calamyzinae and Chrysopetalinae, nine genera and 20 species were determined. Of these, ten species have been previously recorded, three are indeterminable and seven are new species: Paleanotus karlyae n. sp., Arichlidon mucropaleum n. sp., Bhawania bastidai n. sp., Chrysopetalum mexicanum n. sp., C. tovarae n. sp. A new genus is proposed, Bhawatsonia n. gen. which includes two new species, B. fusa n. sp. as its type species, B. nenoae n. sp. and, the new combination and neotype of B. purpurea n. comb. An updated and revised checklist of all chrysopetalids species recorded in the region is included, currently composed of 16 genera, 30 species, and four morphospecies.

Evidence of the Early Holocene eruptive activity of Volcán de Colima and the 8.2 kyr global climatic event in lacustrine sediments from a debris avalanche-dammed lake

Abstract Volcán de Colima, one of the most active volcanoes in Mexico, experienced at least nine flank failures during the last 30 000 years, with catastrophic effects on the environment that implies the formation of temporary dams where lacustrine sediments accumulated for hundreds of years. These lacustrine sequences preserve an exceptional record from which to reconstruct the effect of subsequent volcanic eruptions and, eventually, contemporary environmental and climatic conditions. Here we analyse an Early Holocene lacustrine sequence, named ‘Gypsum King’, which accumulated in a short-lived temporary lake, likely formed by emplacement of the 10 755–11 230 cal years BP Mesa-Yerbabuena debris avalanche. Through detailed analysis of the 1.8 m thick lacustrine sequence ( 14 C ages, sulfur content, grain size), it was possible to identify the 8.2 kyr global climate event and better constrain the Early Holocene main sub-plinian to plinian eruptions of Volcán de Colima. The results presented here highlight the potential to explore sulfur content and abrupt change in grain size in lacustrine sediments as additional proxies to better constrain eruptive phases in volcanic environments. Finally, the Gypsum King sequence provides the first evidence of the 8.2 kyr global climate event along the Eastern tropical Pacific Coast.

Coastal response to the passage of tropical cyclone Juliette on the Central Pacific Coast of Mexico

In situ coastal oceanographic and meteorological data were collected on the Mexican Tropical Pacific coast near Barra de Navidad, Jalisco, Mexico during September 2001 from before and after the passing of Hurricane Juliette. When the leading and trailing edges of the hurricane passed through the study area, wind speeds reached 15 m s-1 and caused a significant deepening of the thermocline, mixing of the upper 40 m of the water column, and a rise in sea level of almost 50 cm at the coast, with effects lasting for about 5 days. A decrease in temperature and an increase in salinity occurred in the upper 20 m, with the opposite occurring below 20 m. Although analyses of open ocean responses to hurricanes are widely available from satellite data, in situ coastal water-column and sea-level data are difficult to acquire, yet crucial to inform coastal flooding models and risk assessment studies. This short data set provides a rare opportunity to explore in situ hurricane effects on this understudied coast.

Satellite-derived turbidity in front of small rivers mouths in the Eastern Tropical Pacific coast of Mexico

Turbidity is a key indicator of water quality. It has biotic effects due to low penetration of light into the water such as photosynthesis reduction. The seasonal and interannual variability of turbidity in the Eastern Tropical Pacific coast of Mexico were analyzed using ocean color data. The region has an extended continental shelf, with several river discharges and marked seasonal patterns of wind. Remote sensing data (1998 to 2017) of reflectance, wind, rainfall, and river discharges were analyzed through Hovmöller diagrams and Empirical Orthogonal Functions. The results indicated that wind stress explained 76% of the turbidity variance, while 8% was explained by river discharges and rainfall. In winter, turbidity is intensified by resuspension mechanisms in front of the southern river mouths. In spring, turbidity increases due to phytoplankton particulate concentrations enhanced by coastal upwelling. During summer and autumn, wind stress is weaker and river discharges increase, thus turbidity increases in front of northern river mouths. El Niño-Southern Oscillation generates turbidity anomalies by alteration of rainfall and wind stress. Despite the proximity of the river mouths, the coastal water turbidity is explained by different processes, which need to be assessed in coastal management.

Semi-annual variations of chlorophyll concentration on the Eastern Tropical Pacific coast of Mexico

An analysis of the main remotly sensed oceanographic variables was conducted to characterize the dominant drivers that modulate the spatial-temporal variability of coastal phytoplankton biomass in the northern limit of the Eastern Tropical Pacific. The phytoplankton biomass was analyzed using monthly average satellite chlorophyll (Chlo) concentration data from MODIS sensors for the period 2003–2017. Oceanographic conditions were analyzed by considering (i) Sea Surface Temperature (SST) high-resolution data from the GHRSST project, (ii) wind stress calculated with data from the zonal and meridional components of the CCMP product, (iii) climatological precipitation, and (iv) climatological river flow. Chlo time series and spatial variability were analyzed using Hovmöller diagrams and Empirical Orthogonal Functions (EOF), respectively. A strong semi-annual signal in Chlo concentration along the coast was observed: the first peak occurs in winter-spring (5.0 mg·m−3) and a second one in summer-autumn (6.5 mg·m−3). A high year-round average of Chlo concentration (3.0–15.0 mg·m−3) was maintained by a 10 km wide along-shore coast, with maximum values spatially associated with river mouths, of which Santiago river registered the highest Chlo values (20.0 mg·m−3). Surface oceanographic conditions showed a marked annual cycle with warmer conditions (30–31 °C) from July to October and colder ones (23–24 °C) from December to April; during the cold period, seasonal wind stress stimulated coastal upwelling. The EOF showed that 70% of Chlo concentration variability was controlled by the semi-annual pattern, which responded to coastal upwelling conditions during cold period, while rivers outflows influenced high Chlo concentration during the warm period. These results highlighted the importance for land-ocean interface to sustain coastal ecosystems' biological production and the major role of watersheds as sources of nutrients to maintain high biological production during warm periods in transitional tropical-subtropical zones.

Human myiasis in Ecuador.

We review epidemiological and clinical data on human myiasis from Ecuador, based on data from the Ministry of Public Health (MPH) and a review of the available literature for clinical cases. The larvae of four flies, Dermatobia hominis, Cochliomyia hominivorax, Sarcophaga haemorrhoidalis, and Lucilia eximia, were identified as the causative agents in 39 reported clinical cases. The obligate D. hominis, causing furuncular lesions, caused 17 (43.5%) cases distributed along the tropical Pacific coast and the Amazon regions. The facultative C. hominivorax was identified in 15 (38%) clinical cases, infesting wound and cavitary lesions including orbital, nasal, aural and vaginal, and occurred in both subtropical and Andean regions. C. hominivorax was also identified in a nosocomial hospital-acquired wound. Single infestations were reported for S. haemorrhoidalis and L. eximia. Of the 39 clinical cases, 8 (21%) occurred in tourists. Ivermectin, when it became available, was used to treat furuncular, wound, and cavitary lesions successfully. MPH data for 2013–2015 registered 2,187 cases of which 54% were reported in men; 46% occurred in the tropical Pacific coast, 30% in the temperate Andes, 24% in the tropical Amazon, and 0.2% in the Galapagos Islands. The highest annual incidence was reported in the Amazon (23 cases/100,000 population), followed by Coast (5.1/100,000) and Andes (4.7/100,000). Human myiasis is a neglected and understudied ectoparasitic infestation, being endemic in both temperate and tropical regions of Ecuador. Improved education and awareness among populations living in, visitors to, and health personnel working in high-risk regions, is required for improved epidemiological surveillance, prevention, and correct diagnosis and treatment.

Major lineages of Loasaceae subfam. Loasoideae diversified during the Andean uplift

The Loasoideae is the largest clade in the Loasaceae. This subfamily is widespread throughout the Neotropics and centered in the Andes, presenting an excellent opportunity to study diversification across much of temperate and mid to high-elevation areas of South America. Despite that, no studies have addressed the historical biogeography of the Loasoideae to date, leaving an important knowledge gap in this plant group. Here, we used four plastid markers (i.e., trnL–trnF, matK, trnS–trnG, and rps16) and sequenced 170 accessions (134 ingroup taxa) to infer the phylogeny of Loasoideae. We then used this phylogeny as basis to estimate divergence times using an uncorrelated relaxed molecular clock approach and seven fossils as primary calibration points. We employed the Dispersal-Extinction-Cladogenesis (DEC) approach to reconstruct the ancestral ranges of the subfamily. Our results indicate that stem Loasoideae diverged from its sister group in the Late Cretaceous to Early Paleocene (ca. 83–62 Ma). The crown node of the whole clade goes back to the Middle Paleocene to Middle Eocene (ca. 60–45 Ma), corresponding to the earliest diversification events of the extant groups, prior to most of the Andean orogeny and roughly coinciding with the Paleocene-Eocene Thermal Maximum. On the other hand, the crown nodes of most genera appear to have originated in the Oligocene and Miocene (median ages: 28–10 Ma). The diversification of some extant lineages appears to have happened in parallel to Andean uplift pulses that seem to have had an effect on the orogeny and concomitant establishment of new habitats and latitudinal corridors. The most likely ancestral areas retrieved for crown Loasoideae, are the tropical Andes and Pacific arid coast. Most of the extant clades have remained restricted to their ancestral areas. Transoceanic Long Distance Dispersal appears to have been involved in the arrival of Loasoid ancestors to South America, and in the distribution of the small clades Kissenia in Africa and Plakothira on the Marquesas Archipelago. The results presented here suggest that the historical biogeography of the continental scale radiation of Loasoideae, follows the sequence and timing of the development of temperate and mid to high-elevation habitats across South America during the Tertiary.

A New Species of Johngarthia from Clipperton and Socorro Islands in the Eastern Pacific Ocean (Crustacea: Decapoda: Gecarcinidae)

The taxonomy of the East Pacific land crab Johngarthia planata (Stimpson, 1860) is reviewed and a neotype designated to stabilize the taxonomy of this species. The population of J. planata is found to be restricted to inshore islands and the continental mainland coast of the tropical and subtropical Pacific coast of America. A new species, Johngarthia oceanica sp. nov., is described for populations that occur on the oceanic Clipperton and Socorro islands. Johngarthia oceanica sp. nov., canbeseparatedfromJ. planatabythebroad, subrectangularmesial lobeof the infraorbitalmargin (narrow, subtriangular in J. planata) and a dorsal carapace that is dark yellow to brightly orange with or without black areas of different extension (homogeneously red to maroon in J. planata). The distribution of J. planata is modeled using MaxEnt and the biogeography of East Pacific species of Johngarthia is discussed. The conservation status of the Clipperton population of J. oceanica sp. nov. deserves special attention because this population may be threatened by introduced rats.

A Review on the Biodiversity and Biogeography of Toxigenic Benthic Marine Dinoflagellates of the Coasts of Latin America

Many benthic dinoflagellates are known or suspected producers of lipophilic polyether phycotoxins, particularly in tropical and subtropical coastal zones. These toxins are responsible for diverse intoxication events of marine fauna and human consumers of seafood, but most notably in humans, they cause toxin syndromes known as diarrhetic shellfish poisoning (DSP) and ciguatera fish poisoning (CFP). This has led to enhanced, but still insufficient, efforts to describe benthic dinoflagellate taxa using morphological and molecular approaches. For example, recently published information on epibenthic dinoflagellates from Mexican coastal waters includes about 45 species from 15 genera, but many have only been tentatively identified to the species level, with fewer still confirmed by molecular criteria. This review on the biodiversity and biogeography of known or putatively toxigenic benthic species in Latin America, restricts the geographical scope to the neritic zones of the North and South American continents, including adjacent islands and coral reefs. The focus is on species from subtropical and tropical waters, primarily within the genera Prorocentrum, Gambierdiscus/Fukuyoa, Coolia, Ostreopsis and Amphidinium. The state of knowledge on reported taxa in these waters is inadequate and time-series data are generally lacking for the prediction of regime shift and global change effects. Details of their respective toxigenicity and toxin composition have only recently been explored in a few locations. Nevertheless, by describing the specific ecosystem habitats for toxigenic benthic dinoflagellates, and by comparing those among the three key regions - the Gulf of Mexico, Caribbean Sea and the subtropical and tropical Pacific coast, insights for further risk assessment of the global spreading of toxic benthic species is generated for the management of their effects in Latin America.

Trophic network properties of coral ecosystems in three marine protected areas along the Mexican Pacific Coast: Assessment of systemic structure and health

Trophic models were constructed to assess the systemic structure, organisation and health of coral ecosystems in three marine protected areas (MPAs) along the Mexican tropical Pacific Coast. Likewise, the degree of resistance of the model-systems and the compartments most sensitive after perturbations were also evaluated. The biomass of the Rhodophyta group was the most abundant compartment in Isla Isabel National Park (IINP) and Islas Marietas National Park (IMNP), whilst the Phytoplankton group had the highest biomass in Sanctuary of Islands and Islets of Bahía Chamela (SIIBC). Based on the magnitudes of Total System Throughput (TST), Ascendency (A), Overhead (Ov), Capacity (C), Average Mutual Information (AMI), Finn’s Cycling Index (FCI) and the Total Biomass/Total System Throughput (TB/TST) ratio, IINP was more mature, organised, developed and healthy than IMNP and SIIBC. Phytoplankton, Detritus and Zooplankton contributed >60% of the total Ascendency, whereas Jacks and Octopus sp. accounted for the complexity of the three MPA model systems. The outcomes of the propagated impacts, using Mixed Trophic Impacts (MTI) and short-term Ecosim simulations (under three levels of mortality: 10%, 30% and 50%), showed that the Groupers (i.e., exploited fish), Omnivorous Fish, Rhodophyta, Large Epifauna and Phytoplankton produced the highest impacts on the remaining compartments of the three model systems. The average System Recovery Time (SRT) suggested that SIIBC was less resilient to disturbances compared with IINP and IMNP. Based on the outcomes, we suggest that the marine zones adjacent to IINP should be included in the Mexican Management Program to create a buffer zone for these coral ecosystems. Likewise, IMNP and SIIBC should be candidates for a putative monitoring programme to assess the trajectory of the systemic health of coral ecosystems. Finally, the trajectories of exploited species should be monitored because they constitute compartments that have relevant roles in the structure and trophic functioning of the three MPAs.

Genetic tracing of farmed shrimp (Decapoda, Penaeidae) in wild populations from a main aquaculture region in Mexico

Release or escapes of aquaculture organisms may impact the genetic composition and variability of wild populations, leading to diverse issues that may compromise long-term wild stock fitness. Therefore, it is relevant to determine if farmed stocks are currently interacting with wild populations. Shrimp farming is an aquaculture activity taking place along the tropical Pacific coast of the Americas, and represents the most important culture bussiness of Northwestern Mexico. In this study, wild and farmed whiteleg shrimp Litopenaeus vannamei from the State of Sinaloa were genetically evaluated to determine admixture levels. A newly developed set of 14 microsatellite markers (mean number of alleles per locus 11.8, and 0.836 expected heterozygosity) was obtained by Next Generation Sequencing to characterize samples. Sampling consisted of 32 wild shrimps collected during three years (2002, 2012, and 2013) and three different sites, and two hatchery stocks from 2007. No significant differences were observed among years in the wild samples, but cluster analyses showed that hatchery-produced individuals were different from wild specimens. Deviations from Hardy-Weinberg Equilibrium and genotype assignment tests indicated that a fraction from each sample could contain individuals from hatchery origin. Even though the estimated fraction of escaped farmed individuals in the most recent samples (2012-2013; mean = 7.1 %) is considered of low genetic risk, management recommendations for hatcheries and farms were provided. Besides, the reasons that explain the intended and unintended farmed shrimp release into the wild were discussed.

¿Dónde cultivar el árbol milagro, Moringa oleifera, en México? Un análisis de su distribución potencial

Native to India, the “miracle tree” Moringa oleifera has been a part of lowland tropical horticulture in Mexico for centuries, where it is mostly grown as an ornamental. With recent recognition of its nutritional, nutraceutical, and industrial properties, there is increasing interest in cultivating the plant beyond its current use as street or patio trees. Based on an extensive compilation of herbarium and our own field observations, we use a tool known as potential distribution modeling to identify the parts of the country with optimal climate for growing moringa. The plant grows best in areas with mean minimum temperatures above 15°C, low rainfall below 1,000mm, and at low elevations below 600 m. This combination of characteristics is found mostly in the dry tropical heartland of the Balsas Depression and the tropical Pacific coast. The states with the greatest suitable acreage for moringa cultivation are Guerrero, Michoacán, Oaxaca and Jalisco, with nine additional states having some suitable acreage. We give a list of 222 Mexican counties by state with optimal climate for moringa cultivation and discuss strategies for cultivating the plant in areas with suboptimal climates.

Hydrology Affects Environmental and Spatial Structuring of Microalgal Metacommunities in Tropical Pacific Coast Wetlands.

The alternating climate between wet and dry periods has important effects on the hydrology and therefore on niche-based processes of water bodies in tropical areas. Additionally, assemblages of microorganism can show spatial patterns, in the form of a distance decay relationship due to their size or life form. We aimed to test spatial and environmental effects, modulated by a seasonal flooding climatic pattern, on the distribution of microalgae in 30 wetlands of a tropical dry forest region: the Pacific coast of Costa Rica and Nicaragua. Three surveys were conducted corresponding to the beginning, the highest peak, and the end of the hydrological year during the wet season, and species abundance and composition of planktonic and benthic microalgae was determined. Variation partitioning analysis (as explained by spatial distance or environmental factors) was applied to each seasonal dataset by means of partial redundancy analysis. Our results show that microalgal assemblages were structured by spatial and environmental factors depending on the hydrological period of the year. At the onset of hydroperiod and during flooding, neutral effects dominated community dynamics, but niche-based local effects resulted in more structured algal communities at the final periods of desiccating water bodies. Results suggest that climate-mediated effects on hydrology can influence the relative role of spatial and environmental factors on metacommunities of microalgae. Such variability needs to be accounted in order to describe accurately community dynamics in tropical coastal wetlands.

Bacterial Diversity in the Soda Saline Crater Lake from Isabel Island, Mexico.

Isabel Lake is a moderate saline soda crater lake located in Isabel Island in the eastern tropical Pacific coast of Mexico. Lake is mainly formed by rainfall and is strongly affected by evaporation and high input of nutrients derived from excretions of a large bird community inhabiting the island. So far, only the island macrobiota has been studied. The knowledge of the prokaryotic biota inhabiting the upper layers of this meromictic lake can give clues for the maintenance of this ecosystem. We assessed the diversity and composition of prokaryotic community in sediments and water of the lake by DGGE profiling, 16S rRNA gene amplicon pyrosequencing, and cultivation techniques. The bacterial community is largely dominated by halophilic and halotolerant microorganisms. Alpha diversity estimations reveal higher value in sediments than in water (P > 0.005). The lake water is dominated by γ-Proteobacteria belonging to four main families where Halomonadaceae presents the highest abundance. Aerobic, phototrophic, and halotolerant prokaryotes such as Cyanobacteria GPIIa, Halomonas, Alcanivorax, Idiomarina, and Cyclobacterium genera are commonly found. However, in sediment samples, Formosa, Muricauda, and Salegentibacter genera corresponding to Flavobacteriaceae family accounted for 15-20% of the diversity. Heterotrophs like those involved in sulfur cycle, Desulfotignum, Desulfuromonas, Desulfofustis, and Desulfopila, appear to play an important role in sediments. Finally, a collection of aerobic halophilic bacterial isolates was created from these samples; members of the genus Halomonas were predominantly isolated from lake water. This study contributes to state the bacterial diversity present in this particular soda saline crater lake.

The Development of Rural Sustainability Using Participatory Action Research: A Case Study from Guatemala

Rural sustainability, although ambiguous at times, is an evolving science on the right way to higher shared value. Despite the rising demand for sustainability, its parameterization is still underdevelopment and differs spatiotemporally. This is a case study of developing rural sustainability using participatory action research (PAR) in small farms in the southern tropical Pacific coast of the Departments of Retalhuleu and Suchitepequez in Guatemala. This study covers five years (2010-2014) of communities’ involvement in open dialogue, field research and project leadership. The data were collected through multi-dimensional approach including hands-on training, surveys with farmers and their families, and public conferences. Exploratory statistical analyses showed that the differences in the responses collected were statistically significant. In addition, the responses on average reflect gratification from the local communities. This validates the positive change of these intervention programs that are both relevant and science-based. The application of PAR in these communities has proved to successfully allow for a two-way learning process between locals and field experts, improve the livelihood and thus sustainability of their lives, and empower them to take initiative with problem-solving actions.

Surface circulation in the Gulf of California in summer from surface drifters and satellite images (2004–2006)

AbstractSurface drifters released in the Gulf of California between June 2004 and August 2006 are used to describe the surface circulation in late spring and summer. In the June to September mean, there was a poleward coastal current on the shelf and slope of the mainland side of the Gulf, with mean speed ∼0.3 m/s; it reached the northern Gulf and joined the cyclonic circulation typical of this zone in summer. In the western half of the southern Gulf, the drifters presented recirculating currents that are due to mesoscale eddies that appear to dominate the surface circulation in summer. In June 2004, the coastal current presented an enhancement event with mean speed around 0.60 m/s and maximum ∼0.80 m/s. It took ∼20 days for a particular drifter to travel the 1000 km from the Gulf entrance to the head. This strengthening of the coastal current was apparent in chlorophyll a and SST satellite images, the drifters following closely the intrusion of warm, chlorophyll‐poor surface water from outside the Gulf. The drifters and the satellite images suggest that the current‐enhancement event lasted less than a month. This mesoscale event was linked with a mesoscale remote forcing in the tropical Pacific coast and with a mesoscale local forcing of the wind. These events seem to occur every year, and are probably important in carrying organisms and properties from the entrance to the whole length of the Gulf.