Alicia Herrera

Universidad de Las Palmas de Gran Canaria | ULPGC · Department of Biology

ETS is an acronym for the activity of the respiratory electron transport system; the ETS assay is a biochemical method for estimating the “potential" respiration (Φ). We apply this technique to suprabenthic species captured at three depths (250 m, 650 m and 850 m) in two different locations: Cabrera (Algerian subbasin) and Sóller (Balearic subbasin...

Plastic production continues to increase every year, yet it is widely acknowledged that a significant portion of this material ends up in ecosystems as microplastics (MPs). Among all the environmental compartments affected by MPs, the atmosphere remains the least well-known. Here, we conducted a one-year simultaneous monitoring of atmospheric MPs d...

In this study, we investigated the concentration, distribution, and characteristics of neustonic MPs in the Canary Islands, with a particular focus on the island leeward zones, where a high accumulation of floating marine microplastics is expected. Samples were collected with a manta net at 15 different sites from Alegranza to La Gomera during the...

Microplastic pollution and associated chemical contaminants is a topic of growing interest. In recent years, the number of publications reporting the presence of microplastics (MPs) in marine organisms has increased exponentially. However, there is a gap in knowledge about the trophic transfer of contaminants from microplastics to animal tissues, a...

Plastic pollution constitutes an environmental problem in the Canary Islands nowadays. Nevertheless, studies evaluating the impact of plastics on its avifauna are still scarce. Gastrointestinal tracts of 88 birds belonging to 14 species were studied for the presence of plastics. Moreover, their livers were analyzed for the determination of bromodip...

The widespread use of plastics correlated with its potential toxic effects is an emerging problem today. Thus, we aimed to test the hypothesis that pairing a commercial fish flake with a 10% microplastic diet can be associated to an increased amount of oxidative stress in adult zebrafish (Danio rerio). The induction of stress response pathways is a...

Alegranza is the most northerly island of the Canary Islands archipelago, the first obstacle crossed by the Canary Current. From July to October 2020, six expeditions were led to the island to make a first inventory of marine debris and its possible source and origin. In total, 3667 objects weighing 321 kg were removed, excluding wooden objects. Of...

Microplastic ingestion was studied in A. aurita, a bloom-forming, circumglobal medusa. Here, we determined whether factors such as the concentration of polyethylene microspheres (75–90 μm) or the absence/presence of prey affect the ingestion, duration of microspheres in the gastrovascular cavity (time of presence), and retention time. The presence...

Marine microplastic pollution is one of the biggest environmental problems we face. The growth of plastic production has not ceased since the 1950s and it is currently estimated that 368 tons of plastic were produced in 2019 (PlascticsEurope, 2020). Geyer et al. (2017) estimate that 79% of the plastic produced in the world still remains in the envi...

Sediment core samples from high tide lines and in submerged zones as well as surface water samples from eight beaches of Tenerife were analysed. Sampling was conducted over a period of one year in intervals of 5 weeks. The majority of particles were found in the high tide sediment (66%), followed by water samples (23%) and finally in sediment from...

Plastic litter dispersed in the different environmental compartments represents one of the most concerning problems associated with human activities. Specifically, plastic particles in the micro and nano size scale are ubiquitous and represent a threat to human health and the environment. In the last few decades, a huge amount of research has been...

Plastic pollution has become a global problem for marine ecosystems. Microplastics (MPs) are consumed by several marine organisms, including benthic and pelagic fish species that confuse them with food sources, thus contributing to bioaccumulation along the food chain. In addition to structural intestinal damage, ingestion of MPs represents a pathw...

The presence of microplastics (MPs) in the marine environment is a concerning topic due to the ecotoxicological effects and possible seafood contamination. Data is needed to evaluate human exposure and assess risks, in the context of a healthy and beneficial seafood consumption. While microplastic ingestion by wild fish has been reported since the...

Plastics are the most important component in marine debris. In turn, within plastics, microplastics (<5 mm) are those that most affect marine biota. Thus, this review has as its main objective to show the current state of studies of microplastics, as well as to determine the groups of vertebrates most affected by microplastics, and the type and pre...

The present study is the first evidence-based study about the ingestion of plastic and microplastics in jellyfish Pelagia noctiluca in the North Atlantic Ocean. A bloom of this organism was collected from Gran Canaria Island coast. It was digested using KOH to quantify the plastic particles and by separating the umbrella from tentacles. About 97% o...

The quantification of microplastics is a needed task to monitor its evolution and model its behavior. However, it is a time demanding task traditionally performed using expensive equipment. In this paper, an architecture based on deep learning networks is presented with the aim of automatically count and classify microplastic particles in the range...

Measuring protein is critical to many investigations in oceanography and marine biology. Here, we compared seven colorimetric protein assays (Rutter, Rutter-SDS, Markwell, BCA, microBCA, Bradford and microBradford) for measuring protein in a mysid (Leptomysis lingvura), in a jellyfish (Pelagia noctiluca), and in three different size fractions of ma...

Marine litter is currently worldwide distributed , and plastic is its principal component. Nevertheless, to date, little is known about how this global threat is affecting the marine coastal areas of the Madeira archipelago (NE Atlantic). In this context, we conducted the first comprehensive survey for marine litter characterization in the region,...

In order to understand the origin of plastic debris pollutants that accumulate in the Canary Islands coastline, six beaches of Gran Canaria Island were studied during different seasons to estimate the abundance and the types of two microplastics fraction sizes (0.01-1 mm and 1-5 mm) and mesoplastics fraction (5-25 mm). For the larger fraction of mi...

Marine microplastic pollution is an issue of great concern nowadays since high concentrations have been detected in the ocean, mainly in the subtropical gyres that accumulate this type of debris. The long-term effects of this pollution on ecosystems and marine biota are still unknown. The aim of this study is to quantify and characterise microplast...

Stranded marine debris from eight beaches of Tenerife (Canary Islands, Spain) was analyzed. Sampling was conducted along the high tide line every 35 m over the whole lengths in periods of 5 weeks for one year. Evaluated particles included all materials bigger than 2 mm, which were subdivided in Mesoparticles (2-10 mm) and Macroparticles (>10 mm). T...

The management of plastic debris is a serious issue due to its durability. Unfortunately, million tons of plastic end up in the sea becoming one of the biggest current environmental problems. One way to monitor the amount of plastic in beaches is to collect samples and visually count and sort the plastic particles present in them. This is a very ti...

We have calculated new production from phytoplankton nitrate reductase (NR) activity and light in the euphotic zone of the Peruvian upwelling system at 15° S. The calculation is based on unique measurements from the Coastal Upwelling Ecosystem Analysis (CUEA) JASON expedition from September 1976. The new production at the 50% light level in the eup...

Given their capacity to adsorb chemical pollutants, microplastics represent a growing environmental concern in the oceans. The levels of 81 chemical compounds in two types of beached microplastic (pellets and fragments) were monitored across the Canary Islands (Spain). The highest concentrations were found for polycyclic aromatic hydrocarbons (PAH)...

Microplastics are small plastic particles, globally distributed throughout the oceans. To properly study them, all the methodologies for their sampling, extraction, and measurement should be standardized. For heterogeneous samples containing sediments, animal tissues and zooplankton, several procedures have been described. However, definitive metho...

Microplastic particles have become an important ecological problem due to the huge amount of plastics debris that ends up in the sea. An additional impact is the ingestion of microplastics by marine species, and thus microplastics enter into the food chain with unpredictable effects on humans. In addition to the exploration of their presence in fis...

Relationship between number of particles/weight in total debris, microplastics (MPs) and tar (1-5mm). *Samples include tar and microplastics.

Marine debris accumulation was analyzed from three exposed beaches of the Canary Islands (Lambra, Famara and Las Canteras). Large microplastics (1-5mm), mesoplastics (5-25mm) and tar pollution were assessed twice a month for a year. There was great spatial and temporal variability in the Canary Island coastal pollution. Seasonal patterns differed a...

We present preliminary results of microplastic measurements in sediments collected in Las Canteras beach, Canary Islands

Presentation of Microtrophic Project

ABSTRACT Nutrient retention efficiency (NRE) is a new metric to quantify the capacity of an ocean layer to maintain its nutrients. Conceptually, it is the remineralization of inorganic nutrients associated with respiratory CO2 production (RCO2) within an ocean layer normalized by nutrients fluxing into that layer. It can be expressed as a ratio or...

Seagrass meadows are important ecosystems on shallow coastal waters, maintaining a high diversity of species. Mysids are the dominant taxa of suprabenthic organisms associated with seagrass meadows in temperate coastal waters, where they are an important food resource for the coastal fishes. Five meadows of Cymodocea nodosa were sampled off the eas...

http://youtu.be/g732bZW4mbk Mysids are peracarida crustaceans with a highly relevant ecological role, especially in coastal areas. This thesis advances our knowledge of Canary Island species especially those that inhabit the coastal Cymodocea nodosa seagrass meadows of Gran Canaria. The cultivation of two species of mysids and a study of their nutr...

The study of electron transport system (ETS) in marine zooplankton provides potential respiration rates from measurements of the maximum activity of the enzymes involved in the respiratory electron transport chain. From these measurement we calculate the metabolic carbon demand to elucidate which group of zooplankton are most influential in the epi...

This paper presents the preliminary results of different trials carried out with two species of mysids from Gran Canaria: Leptomysis lingvura (G.O. Sars, 1866) and Paramysis nouvel. Experiments lasting 21 days showed significantly higher fecundity and survival in L. lingvura than in P. nouveli (P<0.05). We also report the biochemical profile of bot...

Mysids are mid-sized planktonic crustaceans present in many coastal regions of the world ocean. Leptomysis lingvura is found along the east coast of Gran Canaria (Spain), associated with the sandy bottom, and living at depths between 5 and 15 metres. L. lingvura is an important component in the food chain as food for many coastal fish, and could be...

The relationship between respiration and the activity of the electron transport system (ETS) is an unresolved issue that begs more understanding, because measuring ETS activity or its equivalent, potential respiration, is the fastest and most synoptic way of assessing respiration (R ) in ocean space. Furthermore, this topic is an entry point to the...

Kleiber’s Law, relating an organism’s biomass (M) with its respiration rate (R), follows the allometric equation, R=aM0.75. It holds over 20 orders of magnitude for R and has gained increasing importance in recent years, because it serves as the basis for the Metabolic Theory of Ecology (Brown et al, 2004). Why does the M-R relationship in Kleiber’...

Respiratory metabolism in Leptomysis lingvura (G.O. Sars, 1866) Mysidacea (mysids) are small crustaceans found in many coastal regions of the world. The mysid, Leptomysis lingvura, lives along the coast of Gran Canaria Island (Spain) on sandy substrate close to the rocks between 5 and 15 meters deep. It is an important component of the coastal foo...

Studies on the relationship between mysids and fish indicate that mysids are one of the most important foods for fish, especially in coastal environments, where they are abundant (Murano, 1999). In aquaculture mysids have to be a very good quality food for the juvenile stages of cuttlefish Sepia officinalis (Domínguez et al., 2001), and adult seaho...

Estudios sobre la relación entre misidáceos y peces, indican que los misidáceos son uno de los alimentos más importantes para los peces, especialmente en ambientes costeros, donde se encuentran en abundancia (Murano, 1999). En acuicultura los misidáceos han demostrado ser un alimento de muy buena calidad para las fases juveniles de sepia Sepia offi...