Isabel Riveiro

• PhD Sea Sciences
• Senior Researcher at Instituto Español de Oceanografia CSIC

Supplementary material for Catalán, I. A., Bowlin, N. M., Baker, M. R., Berg, F., Brazier, A., Brochier, T., … Ospina-Álvarez, A. (2025). "Worldwide Appraisal of Knowledge Gaps in the Space Usage of Small Pelagic Fish: Highlights Across Stock Uncertainties and Research Priorities." Reviews in Fisheries Science & Aquaculture, 1–62. https://doi.org/1...

Understanding the spatial structure of life cycle components of small pelagic fish (SPF) stocks is key for deciphering population dynamics and ensuring sustainable management. The spatial extent of different life stages and ecologically relevant processes (e.g., reproduction) is temporally dynamic and responds to environmental, genetic, and demogra...

Supplementary tables for Catalán, I. A., Bowlin, N. M., Baker, M. R., Berg, F., Brazier, A., Brochier, T., … Ospina-Álvarez, A. (2025). Worldwide Appraisal of Knowledge Gaps in the Space Usage of Small Pelagic Fish: Highlights Across Stock Uncertainties and Research Priorities. Reviews in Fisheries Science & Aquaculture, 1–62. https://doi.org/10.10...

El atún rojo del sur (Thunnus maccoyii, SBT) se distribuye ampliamente en regiones templadas del hemisferio sur, desde la que los ejemplares adultos migran a la única zona de puesta conocida, situada entre Java y Australia. El atún blanco (Thunnus alalunga, ALB) es un depredador epi-mesopelágico migrador que habita mares tropicales y templados de t...

The mean weight-at-age of fish species is an indicator of fish growth and physiological condition, as well as a basic parameter for assessing and managing fish stocks. Here, we investigate the temporal trends of the mean weight-at-age of four different commercial species with different life strategies: (i) the short-lived pelagic European sardine (...

The European sardine is a key species in the Iberian Peninsula, both socio-economically and for the marine ecosystem. It spawns in the cold months, peaking between November and January, but accumulates energy reserves throughout the warm months in the form of fat to be used during the spawning season. Therefore, the sardine's nutritional condition...

The anchovy present in the European Atlantic waters is separated in two distinct stock management units, one distributed in the Bay of Biscay (ICES Sub-Area 8) and the other distributed in ICES Division 27.9.a. Scientific advice for Div 27.9.a stock relies on the proposal of considering two different components, the western component (subdivisions...

Southern bluefin tuna (Thunnus maccoyii, SBT) and Skipjack tuna (Katsuwonus pelamis, SKJ) are economically important top predator species. SBT is distributed in temperate regions of the Southern Hemisphere, while SKJ mainly occupies tropical and subtropical waters of all major oceans. Despite their importance and long history of research, there hav...

Southern bluefin tuna (Thunnus maccoyii, SBT) is an important commercially and highly migratory species distributed in temperate regions of the Southern Hemisphere. Adults migrate to the only known spawning area in the tropical eastern Indian Ocean. Although there are several ecological and growth studies of SBT juveniles and adults, the main studi...

The European sardine (Sardina pilchardus, Walbaum 1792) is indisputably a commercially important species. Previous studies using uneven sampling or a limited number of makers have presented sometimes conflicting evidence of the genetic structure of S. pilchardus populations. Here, we show that whole genome data from 108 individuals from 16 sampling...

The ICES Working Group on Southern horse mackerel, anchovy and sardine (WGHANSA) assessed the status of anchovy in Atlantic Iberian waters (ane.27.9a; western and southern components) and horse mackerel in Atlantic Iberian waters (hom.27.9a) in the May meeting. The status of anchovy in Bay of Biscay (ane.27.8), sardine in southern Celtic Seas and t...

In Portugal, small and medium pelagic species such as sardine (Sardina pilchardus), chub-mackerel (Scomber colias), anchovy (Engraulis encrasicolus) and horse mackerel (Trachurus trachurus) are the most landed species in the purse seine fishery, accounting for near 50% of total landings in weight. Historically, sardine has been the target species o...

Spawning habitats of cold-water, European small pelagic fishes have shifted poleward in the last three decades coincident with gradual ocean warming. We predicted present-day, season-specific habitat suitability for spawning by European sardine Sardina pichardus in the Atlantic Ocean and Mediterranean and Black Seas, and projected climate-driven ch...

The European sardine ( Sardina pilchardus , Walbaum 1792) is indisputably a commercially important species. Previous studies using uneven sampling or a limited number of makers have presented sometimes conflicting evidence for the genetic structure of S. pilchardus populations. Here we show that whole genome data from 108 individuals from 16 sampli...

Whole genome sequence data is an ideal tool for characterizing processes in ecology and evolution. New population genomics data analysis pipelines based on genotype likelihoods allow for a significant reduction in cost by efficiently extracting information from low coverage sequence data. We demonstrate the robustness of such approaches with a geno...

The purse-seine fishery is the most important Portuguese fishery, accounting for 55% of total landings by weight in 2019 (DGRM, 2020), targeting small pelagic species primarily sardine (Sardina pilchardus). With the decline of the sardine stock and the reduction of annual quotas, this fleet has supplemented its yields with chub mackerel (Scomber co...

Climate change often leads to shifts in the distribution of small pelagic fish, likely by changing the match-mismatch dynamics between these sensitive species within their environmental optima. Using present-day habitat suitability, we projected how different scenarios of climate change (IPCC Representative Concentration Pathways 2.6, 4.5 and 8.5)...

Whole genome sequence data is an ideal tool for characterizing processes in ecology and evolution. Despite the lowering in sequencing costs, it can be challenging to produce a genome and high-coverage resequencing data for a non-model species. New population genomics data analysis pipelines based on genotype likelihoods allow for a significant redu...

The Workshop for the evaluation of the Iberian sardine HCR (WKSARHCR) met to evaluate a new harvest control rule proposed by Portugal and Spain for the management of the Iberian sardine stock. Maximum Sustainable Yield (MSY) and Precautionary Approach (PA) reference points were re-examined. FMSY was recomputed using the management strategy evaluati...

Detailed guide for otolith reading to determine age for stock assessment of sardine (Spanish version of ICES protocols)

The Workshop on the Iberian Sardine Management and Recovery Plan, chaired by Manuela Azevedo (Portugal), met in Lisbon, Portugal, 1–5 April 2019 to evaluate if the management and recovery strategies jointly proposed by the Portuguese and Spanish administration meet the client´s objective and are precautionary according to ICES precautionary criteri...

This work investigated adult-mediated connectivity and spatial population structure of sardine in the European Atlantic waters. The spatial and temporal progress of cohorts was modelled using abundance-at-age survey data by area in the period 2000–2016, covering the region from the northern Bay of Biscay to the eastern Gulf of Cadiz. A novel method...

This paper describes a methodology that combines meta-population theory and stock assessment models to gain insights about spatial heterogeneity of the meta-population in an operational time frame. The methodology was tested with stochastic simulations for different degrees of connectivity between sub-populations and applied to two case studies, No...

Parameters used in the population and fishery simulation loosely based on Northeast Atlantic sardine Sardina pilchardus). (PDF)

Simulation study conditioning. Top figures show the stock recruitment relationships used in the simulation study. The Beverton and Holt curve was used for the cod like stock (right panel), while a Ricker curve was used for the sardine stock (left panel). The different lines refer to values of steepness of the stock recruitment relationship. Bottom...

North Sea cod—Model sensitivity analysis. (PDF)

Northeast Atlantic sardine—Model sensitivity analysis. (PDF)

Parameters used in the population and fishery simulation loosely based on North Sea cod (Gadus morua). (PDF)

The trophic position of sardine (Sardina pilchardus) in spring was determined from the analysis of the natural abundance of stable nitrogen isotopes in the southern Bay of Biscay between 1998 and 2014. Mesozooplankton (200-500. μm) was employed as the reference baseline, as its isotopic signature tracked the seasonal development of phytoplankton bl...

Widely distributed species, such as sardine, are often structured in multiple regional populations connected by dispersal/advection of early life stages and migration/straying of juveniles and adults. Core regional populations of sardine are linked to hotspots of recruitment located in high productivity retention areas: northern and central Bay of...

This study describes fisheries, stock status, ICES advice and management measures for the Northern and Southern sardine stocks in EU Atlantic waters. Information on sardine biology and ecology is provided for a better understanding of stock development. Social and economic dimensions are addressed for sardine fisheries in France, Spain and Portugal...

2014. Age determination procedures on small and medium pelagic species in Spanish Institute of Oceanography (IEO). Int. Doc. IEO, 40 pp. http://hdl.handle.net/10508/1732

This study demonstrates the utility of trawl data, collected during acoustic surveys of pelagic fish stocks as a way of confirming fish identification, to characterize the pelagic community, as well as allowing description and prediction of fish distribution patterns, based on data from Spanish Atlantic Ocean shelf surveys during spring 2005-2011....

The spatial stock complexity of marine fish species requires that population structure is taken into account in fisheries management. The aim of this study was to determine whether the amino acid composition (AAC) of the adult fish allows the identification of subpopulations within the stock. During a cruise in November 2003 along the entire Medite...

Recruitment variability is an important component of the dynamics of Iberian sardine (Sardine pilchardus ). Since 2006, poor recruitment has led to a decrease in stock biomass, the latest in a series of such crises for sardine fisheries. Understanding the mechanisms behind recruitment fluctuations has been the objective of many previous studies, an...

ICES/NAFO Decadal Symposium 2011 ILOTOFPEL (LOng-Term variability OF small-PELagic fishes at the North Iberian shelf ecosystem) will characterize the long-term variability in the pelagic ecosystem at the North Iberian shelf (NIS) and analyse its consequences on the dynamics of the populations of small-pelagic fishes. The analysis will consider...

It is not clear whether global warming will favour or reduce global ocean phytoplankton productivity in coastal areas. Moreover, the relative contributions made by natural and/or anthropogenic factors to possible changes in phytoplankton productivity are not clear. As the relationship between primary production and alongshore wind forcing is well e...

The taxonomic identification of fishes is a time-consuming process for those who are not specialists and, therefore, are more liable to make mistakes. We measured morphometric characters in more than 8900 individuals belonging to 6 classes, 43 orders, 192 families, 510 genera and 847 marine and freshwater species. The aim was to determine if the ta...

The aim of this study was to identify the factors responsible for the differences in chlorophyll a concentration (Ch1-a) observed between the California, Canary, Humboldt and Benguela upwelling areas. Monthly climatologic values of Ch1-a obtained from satellite images, covering the years 1998-2004, revealed that this pigment was higher in the Bengu...

This study focuses on the interactions between toxic phytoplankton and zooplankton grazers. The experimental conditions used are an attempt to simulate situations that have, so far, received little attention. We presume the phytoplankton community to be a set of species where a population of a toxic species is intrinsically diverse by the presence...

The role of mesozooplankton grazers in the development of monospecific algal blooms has often been examined in a scenario in which grazers, depending on their abilities of recognition, select against toxic species and increase grazing pressure on non-toxic species. Here, we present a different ecological scenario in which grazers may select between...

Egg and larval abundance, obtained from annual summer cruises carried out in the Strait of Sicily during 6 years (1997 to 2002), was used to identify the spawning and retention areas of the anchovy Engraulis encrasicolus. Larval amino acid composition was used to analyse the nutritional condition of the larvae collected during the 2002 survey. As t...

Two important issues in the studies of harmful algae include ecological role of the toxic compounds and their fate through the food web. The aims of this study were to determine whether the production of domoic acid is a strategy evolved to avoid predation and the role of copepods in the fate of this toxic compound through the food web. The copepod...

The aim of this work was to study the influence of bacterial epiflora on egg hatching of the sardine (Sardina pilchardus) obtained from a natural environment (Ría de Vigo, Spain) during the spawning season of the sardine (from January to June). Total bacteria, viable bacteria or the presence of specific potential pathogens for eggs, such as Pseudoa...

Positive parental effects, defined as the strategies displayed by sardine Sardina pilchardus adults to increase the survival of eggs and larvae, were studied off the coast of the Iberian Peninsula (Spain) by monthly sampling of eggs and larvae in Ría de Vigo, over a period of 4 yr. Two different parental strategies were observed over the spawning p...

Climatic warming is affecting oceanic circulation patterns in coastal upwelling areas, but the impact of this climatic change on pelagic fish populations remains unclear. From juvenile landings collected over 38 years, the thresholds of environmental factors were determined that limited the optimal environmental window (OEW) for sardine (Sardina pi...

We analysed the amino acid composition (AA) of eggs and larvae of the pelagic fish species Sardina pilchardus (sardine), Scomber scombrus (mackerel), Trachurus trachurus (horse mackerel) and Micromesistius poutasou (blue whiting) collected along the west Atlantic coast of Spain and from the Cantabrian Sea during March to April 2000. A discriminant...

An ingestion experiment was carried out in Rı́a de Pontevedra (Spain) with the copepod Temora longicornis in order to determine ingestion rates of the DSP toxin-producers, Dinophysis spp. (Dinophyceae), and the excretion rate of Dinophysis spp. cells within the faecal pellets. Ingestion rate was a function of dinoflagellate abundance and did not va...

The fate of paralytic shellfish poisoning (PSP) toxins ingested by the copepod Acartia clausi was studied in unialgal and mixed cultures of the toxic dinoflagellate Alexandrium minutum and the non-toxic dinoflagellate Prorocentrum micans. Acartia clausi fed actively on Alexandrium minutum, but feeding pressure diminished over time. This reduced fee...

In this study, marker pigments analysed in incubation feeding experiments and monthly amino acid composition (AAC, weight percentage of total amino acids yields) of copepods collected over 1 yr from the field were used to estimate the food niche of 4 co-occurring copepod species: Acartia clausi, Oithona nana, Temora longicornis and Euterpina acutif...

Unialgal and mixed cultures of the toxic dinoflagellate Alexandrium minutum and the non-toxic dinoflagellate Prorocentrum micans were cultured under phosphate (P) limitation (<1 muM), in the presence or absence of the copepod Acartia clausi. The aim was to determine the possible effects of interspecific competition, predation and nutrient limitatio...

The aim of this study was to determine how climatic (North Atlantic Oscillation winter index, NAO, December through March), oceanographic (upwelling intensity, turbulence, water column stability and larval offshore transport) and biotic (adult abundance) factors affect recruitment success of Sardina pilchardus off the northwest coast of the Iberian...

A combined field and laboratory study was carried out to determine the importance of parental effects (spatial and temporal variations in spawning, egg size and biochemical composition of the egg) on larval survival in Sardina pilchardus. Egg abundance was positively correlated with the seston organic content (SOC; a combination of total protein, c...

Several experiments were performed to determine the effects of cell toxin concentration, composition and toxicity of Alexandrium minutum on ingestion rate, egg production, hatching success and naupliar fitness of the copepod Acartia clausi. A combination of A. minutum and nontoxic algae (Prorocentrum micans, Tetraselmis suecica and Isochrysis galba...

A field study was carried out to determine the relative importance of both food quantity and food quality to reproduction of the copepod Euterpina acutifrons. The total protein concentration of the seston 3 to 20 mu m size fraction was used as the indicator of food available for copepods in the field. Food quality was quantified by comparing the am...

This study was carried out during an autumn bloom of Dinophysis acuminata in the Galician Rias Bajas (NW Spain). The main objective was to determine whether any of the predominant zooplankton species could ingest and transfer toxins through the pelagic food web. Grazing experiments showed that the copepods Temora longicornis and Oithona nana and th...

The essential amino acid composition (EAA) of females and eggs of Euterpina acutifrons and their food was analyzed on copepods fed with different microalgae and collected from the field. There were not significant differences in the EAA of females, but the EAA of eggs varied according to food source. As predicted by homeostasis theory, a higher rep...

The aim of this study is to establish possible associations between temperature, salinity and egg and larval abundance, and the biochemical composition of wild fertilised eggs and larvae of marine fish species. Eggs and larvae of the most abundant species at each station at the time of sampling were collected during 2 surveys carried out from 25 Ma...