Regular talks

Estimation of frictional coefficients across a barrier reef. Case study: San Andrés Island, Colombian Caribbean sea

Speaker: Juan David Osorio Cano, Universidad Nacional de Colombia

The transformation of surface gravity waves across a barrier reef is examined through field measurements. Pressure sensors were located offshore the reef crest. Wave energy fluxes and near-bottom velocities were estimated to characterize wave energy dissipation process and reef roughness. This study suggests that healthy reefs with high coral cover may provide greater coastal protection, highlighting the importance of field data to correlate the bottom reef surface and coral species distribution.

Tidal-river interactions in the estuary of the Magdalena River. Redefining the estuary extension

Speaker: Oscar Álvarez Silva, Universidad del Norte, Colombia

The celerity and damping of the tide -in the non-converging and river dominated estuary of the Magdalena River- is analysed. To do so, data from a set of water level gauges installed along the last 40 km of the river is used and complemented with an analytical derivation of the N-S equations for tidal wave propagation in estuaries. As a result, we were able to revisit fundamental aspects of this estuary such as its extension, frictional effects of the channel and tide-river interactions.

The Role of submerged canopies in releasing wave-induced steady currents shoreward

Speaker: Alejandro Cáceres, University of Toulon, France

The generation of a shear layer in the velocity profile at the canopy top, increases the wave stress term. A dimensional analysis to the momentum equation is performed at the wavelength (λ) and water depth (h) spatial scales over a long time period (t), in order to develop a depth dependent wave-induced steady current, as function of the incoming wave characteristics and submerged canopy properties. The analytical model is compared with laboratory data and numerical data, so that the model could be extended to coastal scale for real-field applications.

Seasonal & inter-annual variability of observed mesoscale eddies in the Caribbean Sea

Speaker: Margarita Eugenia Lopez Alzate, Universidad Nacional de Colombia

Mesoscale eddies are ubiquitous features in the ocean, that exhibit different properties with respect to their surroundings. They are relevant structures for the redistribution of energy and mass around all the oceans. The main statistical characteristics of mesoscale eddies in the Caribbean Sea -as well as the seasonal and inter-annual variability in the number of eddy observations from satellite-based sea level anomalies- were assessed for the period between 1993 and 2016.

Differences in Sea Surface Temperature and Sea Level in the Colombian marine coasts by the year 2100 according to MPIOM data

Speaker: Corinne Daniela Gonzalez Duque, Universidad Nacional de Colombia

Anthropogenic forcing generates observable climate changes in sea surface temperature (SST) and sea level (SL) across the planet. As the Colombian Caribbean and Pacific coasts are vulnerable to this forcing, in this article we use the results of the Max Planck Institute Ocean Model (MPIOM) to describe the SST and SL for the year 2100 in the study areas.

Turbulent analysis of the effects of the roughness of a coral specimen under steady flow conditions

Speaker: Juan Pablo Ramírez Monsalve, Universidad Nacional de Colombia

Study of the roughness provided in turbulent motions by the living tissue in the coral specimen of the Stylophora pistillata, through the exposure of the same coral structure with and without living tissue to four equivalent flow rates. This, in order to relate the coral health state to the hydrodynamic processes developed around the coral via turbulent quadrant analysis.

Parametric hurricane wind model and methodology for the construction of wind and wave database for extreme conditions

Speaker: Mariana Roldán Upegui, Universidad Nacional de Colombia

New on-site data methodology for the construction of hurricane wind fields to improve the estimation of asymmetry of maximum wind speed and some wave parameters.

Atmospheric water transport between the Caribbean Sea, North of South America, and the tropical Pacific Ocean: connections with ocean

Speaker: Gladys Bernal, Universidad Nacional de Colombia

Differences in salinity between the Pacific and the Atlantic are maintained by the atmospheric humidity transport that occurs from the Atlantic to the Pacific, through several low-level jets in the tropical region. We present the atmospheric water flows in the equatorial South America and Central America. Their balance on the Caribbean and Pacific catchment areas -continent and ocean- represent water received or lost by the ocean, influencing the salinity of the Colombian and Panama basins over different time scales.

Biomechanical ecosystem services in coastal protection along temperate climate coastlines of the North Sea

Speaker: Oliver Lojek-Technical University Carolo, Germany

The research project “Gute Küste Niedersachsen” investigates salt marsh and dune systems of Lower Saxony to incorporate ecosystem services into coastal protection design guidelines and to promote integrated coastal zone management. A systematic observation of vegetation regarding zonal occurrence, growth, density, and biomechanical -as well as root properties- will be conducted along with measurements of environmental parameters, to model the wave-vegetation-soil interaction with vegetation surrogates.

From papers to parameters: applying meta-analyses to provide ecosystem models with quantitative sensitivity of tropical marine organisms to ocean acidification and warming

Speaker: Kaitlyn B. Lowder, University of Hawaii

For a Hawaiian Islands Atlantis ecosystem model, we produced quantitative sensitivity parameters that link changes in pH and temperature to changes in organismal biomass. To do this, we applied a meta-analytic framework for organisms in tropical coastal waters fitting mixed effects models with effect sizes. In addition, we identified functional groups and geographical regions where studies of ocean acidification and/or warming responses are limited, highlighting the need for additional research.

Quantitative assessment of inter and intrapopulation isotopic niche patterns between invasive lionfish and native mesopredators

Speaker: Juan Pablo Lozano Peña, Universidad Jorge Tadeo Lozano, Colombia

Despite invasive lionfish can significantly affect coral reef ecosystems through predation on native fishes, there is a paucity of knowledge on lionfish impacts over native mesopredators. Using stable isotope analysis, this study aims to provide an in-deep comparative assessment of inter and intraspecific trophic patterns between lionfish and two important native species, generating useful information to predict to which extent the lionfish may affect local mesopredator populations.

Diversity of drift macroalgae in Aruba, Netherland Antilles, Caribbean Sea

Speaker: Brigitte Gavio – Universidad Nacional de Colombia

Drift and wrack algae were collected from Aruba for taxonomic survey. A total of 73 species were identified: 7 species of Cyanophyta, 38 Rhodophyta, 13 Phaeophyceae, 13 Chlorophyta, and two angiosperms. Of these, 62 species are new records for Aruba. Due to the absence of floristic study in the island, the present work increases by 205% macroalgal diversity of the island. Dasya puertoricensis is reported for the first time outside its type locality. At Eagle beach the drift was dominated by deepwater species.

Wind speed reduction and habitat provision by mangrove at Colombian Caribbean oceanic islands: first defense line to protect infrastructure and provide habitat for fish communities

Speaker: Diana Carolina Castaño Giraldo, Universidad Nacional de Colombia

This study -developed at the San Andres, Providence and Santa Catalina Archipelago in Colombia-, aimed to highlight the importance of mangroves to reduce wind speed, as well as fish nurseries. The island infrastructure and households are exposed to high speed winds due to its oceanic location, influenced by tropical storms and hurricanes that may cause structural damage. We found that just one single mangrove tree can reduce 70% of wind speed on average, while providing habitat for ecologically important species such as parrotfishes.

Impacts of ocean acidification and warming on tropical marine suspension-feeders

Speaker: Vanessa Yepes Narvaez, Manchester Metropolitan University, England

This short-term study evaluated the biological responses of the tropical Indo-Pacific ascidian Polycarpa captiosa to ocean acidification and warming. The responses were assessed by the analysis of their resilience and clearance, absorption and ingestion rates. Animals reacted by skin shedding and gut ejection -a novel discovery in Chordates- after all high temperature and elevated pCO2 treatments, and 20% mortality was observed.

Presence of microplastics and mesoplastics in coral reef and mangrove fishes, Isla Grande, Colombian Caribbean

Speaker: Valeria Jiménez Cárdenas, Universidad Javeriana, Colombia

Pollution caused by plastics has impacted marine ecosystems. The difference that exists between the presence of microplastics in fishes of coral reef and those of mangroves was determined. All species were found to have ingested microplastics and mesoplastics, with a significantly higher average abundance in the mangrove species. This study highlights the importance of performing rigorous monitoring of the presence of plastics in the Colombian Caribbean.

Latitudinal patterns of offspring size in reef coral species

Speaker: Nataly Gutierrez-Isaza, University of Queensland, Australia

We tested for a latitudinal gradient in egg size in scleractinian reef corals and confirmed that corals conform to Rass’s rule, indicating that positive selection towards larger offspring (egg) size occurs with increasing latitude as larger eggs favor offspring fitness. Given that egg size varies with latitude within individual species, it is likely that this plastic trait will play an important role in modulating the adaptive potential of corals under changing thermal conditions following climate change.

Scientific Tourism on remote beaches, a divergent bet for tourists from a new world

Speaker: Bianca Suárez-Puerta, Remonautas Playascorp, Colombia

In another world where we used to live, there weren’t beach tourism alternatives in Colombia to those degrading the environment with unsustainable commercial processes. Given this, we developed a network of scientific tourism in remote beaches, an applied marine research project that executes a knowledge management model in remote marine-coastal areas with high socio-natural value. Our aim is to know, protect, restore and promote the sustainable use of these fragile ecosystems.

Coastal community inclusion in an offshore marine protected area. Prospects and challenges for management and investigation

Speaker: Sebastián Martínez, Parque Nacional Natural Corales de Profundidad, Colombia

In the Colombian Caribbean, the discovery of deep areas with high biodiversity led to the creation of the Corales de Profundidad National Natural Park in 2013. It is located 18 nm from the coast, to conserve deep-sea ecosystems, its goods and services. The fishing regulations of the park generated an important social impact in local communities, leading us to include the coastal communities in the conservation strategies of the NNP.

Conservation of the hawksbill turtle (Eretmochelys imbricata) in Rincón del Mar, Sucre, Colombia

Speaker: Nicolás Restrepo Garzón, Universidad de los Andes, Colombia

In this study, we present the record of six hawksbill turtle nests in Rincon del Mar, Colombia, as a result of the local community strengthening, interinstitutional work and participatory monitoring.

Comparison between in situ and satellite sea surface temperature in whale shark distribution areas at northeast of Yucatan Peninsula, Mexico (2005 – 2020)

Speaker: Jorge A. Trujillo-Córdova, Universidad Autónoma del Carmen, México

The marine coasts of Mexico are home to whale sharks. The largest aggregations of this species occur in the Caribbean Sea. Since 2005, a multidisciplinary research group established a whale shark habitat monitoring, to understand the ecology of this species at the northern of the Caribbean Sea.

Harnessing big and open datasets for mangrove mapping, species conservation, and decision-making for blue carbon investments in Colombia

Speaker: Juan Felipe Blanco-Libreros, Universidad de Antioquia, Colombia

Scientist and natural resource managers currently face three challenges regarding the study, conservation and sustainable use of mangroves in Colombia: Updating distribution maps, designating new marine protected areas and identifying potential areas for investing on blue carbon projects. We present examples of mangrove mapping using Google Earth Engine, identifying threats for a vulnerable mangrove species, using national open geodata and identified areas for potential blue carbon projects.

Fish Aggregating Devices as potential oceanographic monitoring platforms in the Eastern Tropical Pacific

Speaker: Estefania Isaza-Toro, Universidad del Valle, Colombia

Marine environmental characterization is often developed from traditional tools of ocean sciences. However, the technological advance in oceanographic instrumentation and the approach of multidisciplinary studies invites to consider non-traditional but complementary sources of information. Our objective was the analysis of spatial-temporal distribution of Fish Aggregating Devices (FADs) as alternative platforms to monitor oceanographic conditions in the eastern region of the Eastern Tropical Pacific (et- ETP).

A quality control measure for wave buoy observations

Speaker: Joey Voermans, University of Melbourne, Australia

Wave buoys are an important data source for met-ocean model validation and calibration. To guarantee the accuracy of their observation, sophisticated quality control measures are required. It is a common practice to apply a standard deviation threshold to detect anomalies or outliers. However, this method cannot distinguish between a rare but natural event and an instrument problem. We present a semi-physical wave anomaly identification method using a phase-space threshold.

Deep Sea Queen Conch Monitoring Using ROV Technologies in the Seaflower Biosphere Reserve, Colombian Caribbean

Speaker:Rubén Azcárate, SEPIAROV, Colombia

For over two decades, the Departmental Government, the National University of Colombia and the CORALINA Corporation have monitored strategic ecosystems for the conservation of marine biodiversity in the Seaflower Biosphere Reserve. However, marine ecosystems deeper than 40 meters have been roughly studied, generating information gaps affecting the processes of recognition and conservation of the population dynamics. Remotely Operated Underwater Vehicles (ROVs) have become a viable alternative to monitor these ecosystems.

Genes associated with resistance and antimicrobial compounds synthesis in a mangrove subjected to contrasting salinities

Speaker: Alejandro Sepúlveda Correa, Universidad Nacional de Colombia

Mangroves are subject to biotic, abiotic and anthropogenic stresses, notable pollution from urban waste. In this context, salinity and wastewater pollution in mangrove ecosystems could affect populations of microorganisms and the relative abundance of genes involved in the biological response to these stressors. This research aimed to identify genes associated with resistance and biosynthesis of antimicrobial compounds in mangrove soils subjected to contrasting salinities.

Microbial composition and diversity in deep-sea sediments in the southern colombian caribbean sea

Speaker: Diana López Alvarez, Universidad del Valle, Colombia

We used a 16S rRNA gene sequencing approach to evaluate the microbial composition and diversity of sediments deep-sea at two sites of the southern Colombian Caribbean Sea, and the relationship of these microbial communities with the effect of six different depths. The deep-sea is considered an extreme environment due to high atmospheric pressure and low temperatures.

Risk assessment of potential tourist-vessel collision with cetaceans in the Colombian EEZ: a tool for whale-watching management

Speaker: Dalia C. Barragán Barrera, CIOH-DIMAR, Colombia

The rapid expansion of tourist vessel-based activities constitutes a potential threat for cetaceans due to vessel collision. Here, we evaluated the potential tourist-vessel collision risk within the Colombian waters for the most common cetacean species, target for whale-watching activities. Results showed that coastal zones had the highest collision risk for all species, so it’s paramount that boat-based touristic operators maintain a vessel speed below 10 knots to mitigate this risk.

Abundance and body size of parrotfishes (Scarus and Sparisoma) at the seaflower biosphere reserve: a characterization

Speaker: Natalia Rivas Escobar, CECIMAR, Colombia

Diver-operated stereo-video technique was used to characterize Scarus and Sparisoma parrotfish populations. Abundance and body size data were collected in 2018, at four nearby localities of the Seaflower Biosphere Reserve. Sparisoma viride was less abundant in San Andrés island. Sparisoma viride and Scarus vetula presented smaller body sizes in San Andrés, while Scarus taeniopterus and Scarus iseri had larger sizes at the same locality. We discussed the way in which our findings can be related to fishing exploitation.

Genetic status and connectivity of Sparisoma aurofrenatum the South Caribbean

Speaker: Dana Alejandra Velasco, Universidad del Valle

Sparisoma aurofrenatum -theredband parrotfish- plays an important ecological role maintaining the balance between corals and macroalgae. Currently, as the populations of commercial fish species are declining, there is an increasing trend towards catching mid-sized herbivorous fish and S. aurofrenatum is not the exception. We explore the genetic status and connectivity of this species, using a mitochondrial gene in 88 individuals. Our results point to a panmictic population, with high genetic connectivity.

Marine recreational fishing as alternative for the development of ecological tourism in Magdalena region, Colombian Caribbean

Speaker: Jorge Paramo, Universidad del Magdalena, Colombia

The objective of this study is to present the spatio-temporal distribution of pelagic fish -object of recreational fishing- in relation to environmental variables such as temperature, salinity and winds in the marine area of the department of Magdalena, Colombian Caribbean. This recreational fishing activity can be carried out as ecological tourism, contributing to the development of the blue economy since it encourages responsible fishing and income.

Understanding the livelihoods of artisanal fishing communities: An approach based on a household production model

Speaker: Jorge H. Maldonado-Universidad de Los Andes, Colombia

In developing countries, artisanal fishing households have livelihood strategies defined by production. This production can be sold or self-consumed. Besides, fishing involves hunting and the production factor associated with natural capital is a non-excludable resource. We propose a theoretical model to understand the livelihoods of artisanal fishing communities. The results of the model are useful for the design of policies intended to ensure the sustainability of resources in fishing communities.