Nuria Raventos

Spanish National Research Council | CSIC · Departamento de Ecología Marina

Mortality at early life stages of fishes is common in nature and can be shaped by stochastic and selective processes. Selective mortality has rarely been assessed in natural conditions but can now be studied by combining genomic data with information on different life stages that realates to fitness. Here we investigate selective mortality between...

Fish recruitment variability results from a complex mix of biological and physical processes, and their interactions, acting in the early life stages. In this study, we aim to investigate the environmental factors driving the recruitment success of blue whiting (Micromesistius poutassou) in the NW Mediterranean through reconstruction of early life...

This study analyses growth rates of bluefin tuna young-of-the-year in the Mediterranean. Potential differences in growth rates were examined between years (2013 and 2016) and regions (eastern, central and western Mediterranean). A total of 134 specimens were aged by analysing otolith microstructure. Fish sizes ranged between 14.7 and 57 cm fork len...

As species struggle to cope with rising ocean temperatures, temperate marine assemblages are facing major reorganisation. Many benthic species have a brief but critical period dispersing through the plankton, when they are particularly susceptible to variations in temperature. Impacts of rising temperatures can thus ripple through the population wi...

Dispersal is a key process shaping species population structure. In demersal marine fishes, which usually have sedentary adult phases, dispersion relies on drifting larval stages. However, the dynamics and seasonal variability of seawater masses can greatly determine the connectivity patterns of these species along the same geographic gradient. For...

Apart from directly influencing individual life histories of species, climate change is altering key biotic interactions as well, causing community processes to unravel. With rising temperatures, disruptions to producer-consumer relationships can have major knock-on effects, particularly when the producer is a habitat-forming species. We studied ho...

Connectivity and local adaptation are two contrasting evolutionary forces highly influencing population structure. To evaluate the impact of early-life traits and environmental conditions on genetic structuring and adaptation, we studied two sympatric fish species in the Western Mediterranean Sea: Symphodus tinca and S. ocellatus. We followed an in...

Life-history traits as growth, age at first maturity, reproduction and condition as well as the size distribution of the commercial and the discarded catch, have been studied for the blue whiting, Micromesistius poutassou, from the NW Mediterranean. This is a species of commercial interest in the area. In the last decade its landings remained at ve...

Abstract Dispersal is one of the main determining factors of population structure. In the marine habitat, well-connected populations with large numbers of reproducing individuals are common but even so population structure can exist on a small-scale. Variation in dispersal patterns between populations or over time is often associated to geographic...

Larval dispersal determines #population structure in marine organisms but is hard to measure precisely. Thanks to a great collaboration, we are trying to go one step further to the very fine scale of dispersal patterns.

Climate warming can affect numerous life aspects in most marine species. The Planktonic Larval Duration (PLD) can be strongly influenced by sea-surface temperature (SST), potentially affecting the dispersal capabilities of fishes. Longer dispersal duration should result in increasing dispersal distance, facilitating connectivity among populations....

Integrating connectivity patterns into marine ecosystem management is a fundamental step, specially for stock subjected to the combined impacts of human activities (overfishing, habitat degradation, etc.) and climate changes. Thus, management of marine resources must incorporates the spatial scales over which the populations are connected. Notwiths...

Otolith microstructure resolved on a daily basis is a valuable tool to identify ecological and oceanographic processes influencing the early life of marine fishes and their recruitment. Counting otolith daily growth increments is time-consuming and, for some species, it lacks of accuracy and precision for estimating the early life larval traits. Mo...

Understanding connectivity patterns among coastal fish populations is a crucial step in the management of marine resources. However, quantifying and measuring the exchange among fish populations is a hard task because of the difficulties in tracking the trajectory and fate of the larval phase. Moreover, there is a lack of basic knowledge about the...

Connectivity is crucial for the persistence and resilience of marine species, the establishment of networks of marine protected areas and the delineation of fishery management units. In the marine environment, understanding connectivity is still a major challenge, due to the technical difficulties of tracking larvae. Recently, parentage analysis ha...

Although the dominant ecological paradigm considers herbivory to play an insignificant role in seagrass ecosystems, past herbivore densities were high enough to result in significant reduction of seagrass growth. To study the long-term impact of sustained and intense herbivory on seagrass meadows, we compared morphological, population and reproduct...

Pelagic larval duration (PLD) and trace elements in otoliths provide basic information to investigate the dispersal history of marine fishes. Due to the paucity of such information in the Mediterranean region, we assessed PLD, hatching and settlement duration and timing, and otolith microelemental composition of the White Sea bream (Diplodus sargus...

Natural geochemical signatures in calcified structures are commonly employed to retrospectively estimate dispersal pathways of larval fish and invertebrates. However, the accuracy of the approach is generally untested due to the absence of individuals with known dispersal histories. We used genetic parentage analysis (genotyping) to divide 110 new...

The influence of distinct demographic factors on determining population size in a littoral nesting fish (Symphodus roissali) was studied. Differences in the overall abundances were studied at three sites in the NW Mediterranean Sea for three years, to examine whether: 1) the adult population determined the number of successful nests; 2) the number...

Population parameters and behaviour of the herbivorous fish Sarpa salpa, present differences between protected and non-protected seagrass meadows of the north-western Mediterranean Sea. Larger individuals are more abundant inside protected areas, where their grazing pressure on seagrass is disproportionately greater than that of smaller fish feedin...

The relative importance of maternal influences and time of reproduction on early life- history traits in the temperate five-spotted wrasse Symphodus roissali was examined. On 5 occasions during the reproductive period, groups of 4 small and 4 large females were collected and their eggs were fertilized with milt from 1 male. This multiple female fer...

The potential of alleviated fishing pressure measures established at the Marine Natural Reserve of Cerbère-Banyuls to affect phenological characters of P. oceanica, the main canopy-forming seagrass, was studied. Our results show differences in some leaf parameters between meadows under fishing prohibition measures compared to those without. In addi...

Summary Life history parameters (age, growth and reproductive characteristics) of the Mediterranean paternal mouthbrooding cardinal fish, Apogon imberbis, were investigated at a coastal locality off Blanes, NW Mediterranean Sea. Maximum age was found to be 5 years for both sexes. Age was validated with an otolith chemical (tetracycline) marking exp...

We examined the relationship between pelagic larval duration (PLD)-a predictor of a species' dispersal potential-and the geographic distribution range of 62 Mediterranean littoral fishes. We found a significant, positive, weak relationship between PLD and distribution range. This relationship was observed in species with long PLDs that can cross th...

This paper examines the possible effects of discharges from a desalination plant on the macrobenthic community inhabiting the sandy substratum off the coast of Blanes in Spain (NW Mediterranean) using multivariate and univariate analyses. Two controls and one putatively impacted location were selected and visual censuses were carried out 12 times b...

The effects of site characteristics on the distribution of nests and nesting success were examined in the five-spotted wrasse Symphodus roissali in the north-western Mediterranean Sea. Nesting males selected nest sites mainly on flat substrata and close to a margin in the rocky littoral strip; however, substratum slope and degree of shelter from wa...

We examined the relationships between daily pattern of settlement and environmental parameters during two consecutive years in two littoral fishes, Lipophrys trigloides (Blenniidae) and Chromis chromis (Pomacentridae), in the NW Mediterranean Sea. We also used individual early-life traits (pelagic larval duration, size at hatching and size at settl...

Correlations between daily fish settlement and environmental and physical parameters were examined during two consecutive years in two labrid species (Symphodus roissali and Symphodus ocellatus) in the NW Mediterranean Sea. Both these species have a short planktonic larval duration (12±0.3 and 9±0.4 days, respectively) and limited offshore larval d...

The characteristics of fish larvae affect settlement and recruitment survival. We examined the effects of the variation in the early life characteristics (pelagic larval growth, pelagic larval duration, size-at-hatching and size - at- settlement) on post-settlement survival in 2 littoral species of the genus Symphodus (S. roissali and S. ocellatus)...

The nesting activity of the littoral five-spotted wrasse, Symphodus roissali , was investigated near Blanes (northwestern Mediterranean Sea). Males construct and defend several nests over the entire reproductive period while females spawn asynchronously in these nests. Nesting activity continued from around the end of March to the end of June in th...

The nesting activity of the littoral five-spotted wrasse, Symphodus roissali, was investigated near Blanes (northwestern Mediterranean Sea). Males construct and defend several nests over the entire reproductive period while females spawn asynchronously in these nests. Nesting activity continued from around the end of March to the end of June in the...

The populations of three sympatric hermit crabs, Pagurus excavatus, Anapagurus alboranensis and Anapagurus petiti were studied in a shallow (15–25 m) sandy area in the north-western Mediterranean. Seasonal abundance, seasonal size frequency, sex ratio and reproductive periods were examined. Pagurus excavatus was the largest and most abundant specie...

The planktonic larval duration (PLD) was estimated for 42 species of littoral fishes from the north-western Mediterranean Sea. Daily increments and settlement marks on the otoliths (sagittae or lapilli) of new settlers and post-settlers were used to determine the larval stage duration. We also used PLD in the new settlers of some species to confirm...

Age and growth patterns of four common species of wrasses, Labrus merula, Coris julis, Symphodus roissali and Symphodus tinca, from the north-western Mediterranean sea are analysed. Length-at-age values are estimated from otoliths from which the first annual hyaline ring is determined by reading daily rings. The growth patterns are well described b...