Search

Este artículo contiene 11 páginas, 5 figuras, 1 tabla., Ongoing human pressures over recent decades have caused the loss and ensuing impoverishment of the complexity and diversity of Mediterranean habitats dominated by algal species of the order Fucales. Gongolaria barbata, a habitat-forming Fucales species that has disappeared in several places across the Mediterranean, was reintroduced in a cove (Cala Teulera, Maó Bay, Menorca) where it was known to have been locally extinct for more than 40 years. Reintroduction was performed in 2011 using innovative non-destructive techniques. Here we describe the expansion patterns of the population ten years after its reintroduction, and we look at the size-structure distribution of the restored population compared to one of the only natural populations known in Spain (Fornells Bay, Menorca). Newly settled individuals exhibit a progressive dispersal pattern from restoration sites, favouring rocky substrates at the shallowest level parallel to the shore. The area occupied by G. barbata has increased by almost three orders of magnitude in ten years, from approximately 3.6 m2 of the initially restored area to a current restored area of 2093 m2. Recruits and juveniles dominate the restored population but some individuals have reached large size classes, the overall size distribution resembling the reference population. The high-resolution cartography included in our study enables an accurate mid to long-term assessment of the expansion of G. barbata. Incorporating such tools in restored marine forests would facilitate the implementation of efficient management policies that will help reinforce their conservation., Funding was provided by IEO (“Mola-Menorca Dos Project”, financed by the Direcció General de Recerca del Govern de les Illes Balears through the European Regional Development Fund).

Este artículo contiene 16 páginas, 7 figuras., 1. Gradual climate change and discrete extreme climatic events have driven shifts in the structure of populations and the distribution of species in many marine ecosystems. The most profound impacts of recent warming trends have been generally observed at species' warm edges and on large conspicuous species. However, given that different species and populations exhibit different responses to warming, and that responses are highly variable at regional scales, there is a need to broaden the evidence to include less conspicuous species and to focus on both local-and regional-scale processes. 2. We examined the population dynamics of canopy-forming seaweed populations situated at the core range of their distribution during a regional marine heatwave (MHW) event that occurred in the Mediterranean Sea in 2015, to determine between-site variability in relation to the intensity of the MHW. We combined field observations with a thermo-tolerance experiment to elucidate mechanisms underlying observed responses. 3. Despite our study populations are located in the species core range, the MHW was concomitant with a high mortality and structural shifts in only one of the two surveyed populations, most likely due to differences in habitat characteristics between sites (e.g. degree of shelter and seawater transfer). The experiment showed high mortalities at temperatures of 28°C, having the most severe implications for early life stages and fertility, which is consistent with warming being the cause of population changes in the field. Crucially, the regional-scale quantification of the MHW (as described by satellite-derived SSTs) did not capture local-scale variation in MHW conditions at the study sites, which likely explained variation in population-level responses to warming. 4. Synthesis. Enclosed and semi-enclosed seas, such as the Mediterranean Sea, often highly impacted by human perturbations, are also global hotspots for ocean warming and are highly susceptible to future MHWs. Our findings highlight that local-scale variability in the magnitude of extreme climatic events can lead to local extinctions of already fragmented populations of habitat-forming seaweeds, even towards the species' core range. However, our results highlight the potential for local-scale climatic refugia, which could be identified and managed to safeguard the persistence of canopy-forming seaweeds., Ministerio de Economía, Industria y Competitividad, Gobierno de España, Grant/ Award Number: CGL2016-76341- R and FPI (BES-2017- 079907); European Maritime and Fisheries Fund EMFF, Grant/Award Number: EASME/EMFF/2017/1.2.1.12/ S4/01/SI2.789059; UK Research and Innovation, Grant/Award Number: MR/ S032827/1; Horizon 2020 Framework Programme, Grant/Award Number: 689518; Generalitat de Catalunya, Grant/Award Number: 2017 SGR 1521; Universitat de Girona, Grant/Award Number: IFUdG-2016 and MPCUdG2016/097; European Regional Development Fund, Grant/Award Number: CGL2016-76341- R; “la Caixa” Foundation, Grant/Award Number: LCF/BQ/ ES17/11600001

Este artículo contiene 12 páginas, 3 tablas, 7 figuras., Marine forests dominated by macroalgae have experienced noticeable regression along some temperate and subpolar rocky shores. Along continuously disturbed shores, where natural recovery is extremely difficult, these forests are often permanently replaced by less structured assemblages. Thus, implementation of an active restoration plan emerges as an option to ensure their conservation. To date, active transplantation of individuals from natural and healthy populations has been proposed as a prime vehicle for restoring habitat-forming species. However, given the threatened and critical conservation status of many populations, less invasive techniques are required. Some authors have experimentally explored the applicability of several non-destructive techniques based on recruitment enhancement for macroalgae restoration; however, these techniques have not been effectively applied to restore forest-forming fucoids. Here, for the first time, we successfully restored four populations of Cystoseira barbata (i.e., they established self-maintaining populations of roughly 25 m2) in areas from which they had completely disappeared at least 50 years ago using recruitment-enhancement techniques. We compared the feasibility and costs of active macroalgal restoration by means of in situ (wild-collected zygotes and recruits) and ex situ (provisioning of lab-cultured recruits) techniques. Mid/long-term monitoring of the restored and reference populations allowed us to define the best indicators of success for the different restoration phases. After 6 years, the densities and size structure distributions of the restored populations were similar and comparable to those of the natural reference populations. However, the costs of the in situ recruitment technique were considerably lower than those of the ex situ technique. The restoration method, monitoring and success indicators proposed here may have applicability for other macroalgal species, especially those that produce rapidly sinking zygotes. Recruitment enhancement should become an essential tool for preserving Cystoseira forests and their associated biodiversity., This project has received funding from the Horizon 2020 EU Research and Innovation Program under grant agreement No. 689518 (MERCES), the Fundación Biodiversidad under the framework of the project: “Conservación y restauración de poblaciones de especies amenazadas del género Cystoseira” and the Spanish Ministry Project ANIMA (CGL2016-76341-R, MINECO/FEDER, UE). This project has also been funded by Dirección General de Innovación e Investigación (Govern Illes Balears) and European Regional Development Fund (FEDER). JV has been funded by a IFUdG-2016 grant.

Este artículo contiene 18 páginas, 8 figuras, 1 tabla., Historical information on marine organisms needs to be incorporated to develop effective management plans and conservation targets. In the Mediterranean Sea most species of brown seaweeds of the order Fucales are threatened or endangered and need protection. Here we merge data on historical and current records to create the first reference dataset on past and present distributions of Fucales from shallow and sheltered shores of Catalonia (NW Mediterranean Sea). Most Cystoseira sensu lato populations were found in the northern shores, where the most suitable environments exist. Carpodesmia mediterranea and Cystoseira compressa are far more abundant in exposed than in shallow, sheltered shores. Populations of most of the taxa (i.e. Carpodesmia crinita, Treptacantha elegans, T. sauvageauana, T. barbata f. aurantia) have suffered an important regression and two taxa have apparently become locally extinct (Cystoseira foeniculacea, Treptacantha barbata f. barbata). Carpodesmia caespitosa is still widespread in sheltered environments from the northern shores and a previously unreported taxon has been found (T. ballesterosii var. tenuior). Our regional-scale study makes available a solid, comprehensive baseline for future monitoring and application of conservation measures for the several threatened species of Fucales., Financial support to this research came from the projects ‘‘Cartografia dels Hàbitats Litorals a Catalunya’’ (Departament de Territori i Sosteniblitatand Institut Cartogàfic, Generalitat de Catalunya, Spain), CTN1500528 of the Agència Catalana de l’Aigua, Spain, and the INTRAMURAL CSIC PIE201730E033. Jana Verdura and Alba Medrano benefitted of funding from the Horizon 2020 EU Research and Innovation Program under grant agreement No. 689518 (MERCES). Partial funding came from the Sustainable Blue Economy program, European Union under the grant agreement AFRIMED EASME/EMFF/2017/1.2.1.12/S4/01/SI2.789059 to Jana Verdura.

In the Mediterranean Sea, many species of Cystoseira, which are important habitat-forming species on shallow rocky bottoms, have gone missing from many coastal areas, impairing essential ecosystem services. Cystoseira crinita forests thrive in very shallow waters from sheltered environments and are currently regressing in several European shores. In the actual scenario of ocean warming it is essential to determine the vulnerability of these populations to thermal stress in order to design future conservation actions. Since the response of this macroalgae to thermal stress may be site-specific, here we compared the thermal tolerance of populations dwelling in the coldest and warmest areas of the Mediterranean Sea. We show that C. crinita populations from warmer areas (Eastern Mediterranean) had a temperature tolerance threshold 2ºC higher than Northwestern Mediterranean populations. There is a strong correlation between the observed differential phenotypic responses and the local temperature regimes experienced by each population. This is the first evidence for the role of thermal history in shaping the thermotolerance responses marine habitat-forming macroalgae under contrasting temperature environments. Financial support from EU2020 (R+I) under grant agreement No 689518 (MERCES) and MINECO (CGL2016-76341-R).

Este artículo contiene 18 páginas, 5 figuras, 3 tablas, Species distribution models (SDMs) have been used to predict potential distributions of habitats and to model the effects of environmental changes. Despite their usefulness, currently there is no standardized sampling strategy that provides suitable and sufficiently representative predictive models for littoral marine benthic habitats. Here we aim to establish the best performing and most cost-effective sample design to predict the distribution of littoral habitats in unexplored areas. We also study how environmental variability, sample size, and habitat prevalence may influence the accuracy and performance of spatial predictions. For first time, a large database of littoral habitats (16,098 points over 562,895 km of coastline) is used to build up, evaluate, and validate logistic predictive models according to a variety of sampling strategies. A regularly interspaced strategy with a sample of 20% of the coastline provided the best compromise between usefulness (in terms of sampling cost and effort) and accuracy. However, model performance was strongly depen upon habitat characteristics. The proposed sampling strategy may help to predict the presence or absence of target species or habitats thus improving extensive cartographies, detect high biodiversity areas, and, lastly, develop (the best) environmental management plans, especially in littoral environments., This study was supported by INTRAMURAL CSIC (0065) and the European Union's Horizon 2020 (689518) MERCES.

Este artículo contiene 8 páginas, 3 figuras, 2 tablas., Identifying scales at which most of the spatial heterogeneity occurs is important to understand how ecological communities are structured. Rocky shore communities are distributed vertically as a response to environmental variables and mainly water availability gradients. There has been much debate about the relative importance of vertical and horizontal variation gradients in littoral community structure and richness. In this study we assessed if horizontal variability is responsible for changes in community structure at a regional scale (hundreds of Km) by restraining vertical variability. We studied ten different rocky shore communities from the upper mediolittoral to the upper infralittoral levels with different geographical distribution patterns. We aimed at assessing if structure and species richness are affected by their geographical position of each community. The results proved that horizontal variation in species composition and richness was community-dependent and there was no common pattern at a regional scale. Communities with a wide geographic distribution typically showed some variation, which was related to changes in the environmental factors across the geographical gradient. This study sheds light on the existence of latitudinal variability in species composition and richness at a regional scale in rocky shores. It also strongly supports the validity of littoral communities and habitats from conservation panels as consistent ecosystem subdivisions and reliable working units., This work was supported by the project INTRAMURAL CSIC Spain [grant number 0065] and the data for this study came from the project “Cartografia dels H�abitats Litorals a Catalunya” (Departament de Territori i Sosteniblitat and Institut Cartogr�afic, Generalitat de Catalunya), the Sustainable Blue Economy program, AFRIMED EASME/EMFF/ 2017/1.2.1.12/S4/01/SI2.789059 and the Spanish Ministry Project ANIMA (CGL2016-76341-R, MINECO/FEDER, UE).

12 páginas, 4 figuras, 4 tablas, The boundary between land and sea, i.e. the littoral zone, is home to a large number of habitats whose distribution is primarily driven by the distance to the sea level but also by other environmental factors such as littoral's geomorphological features, wave exposure, water temperature or orientation. Here we explore the relative importance of those major environmental factors that drive the presence of littoral rocky habitats along 1100 Km of Catalonia's shoreline (Spain, NW Mediterranean) by using Geographic Information Systems and Generalized Linear Models. The distribution of mediolittoral and upper infralittoral habitats responded to different environmental factors. Mediolittoral habitats showed regional differences drawn by sea-water temperature and substrate type.Wave exposure (hydrodynamism), slope and geological features were only relevant to those mediolittoral habitats with specific environmental needs. We did not find any regional pattern of distribution in upper infralittoral habitats, and selected factors only played a moderate role in habitat distribution at the local scale. This study shows for the first time that environmental factors determining habitat distribution differ within the mediolittoral and the upper infralittoral zones and provides the basis for further development of models oriented at predicting the distribution of littoral marine habitats., Financial support for this work was provided by projects INTRAMURAL CSIC 0065 “Estudios para la implementaci on de las Directivas Europeas H abitats, Marco del Agua y Estrategia Marina en el Mediterr aneo Español”.

10 páginas, 5 figuras, 1 tabla., Vertical variation in the distribution of rocky shore assemblages is greater than horizontal variation, as shown by univariate and multivariate analysis performed with data obtained along 1000 km of shoreline and covering from the upper supralittoral to the upper infralittoral zone ( 1 m). Consequently, vertical littoral zonation is a consistent pattern at a regional scale within the same biogeographical zone. While their distribution varies at the same shore height, marine species and assemblages from rocky shores show a specific vertical sequence known as zonation. A key question in ecology is how consistent is zonation along large spatial scales. The aim of this study is to show distribution patterns of littoral assemblages at a regional scale and to identify the most relevant abiotic factors associated to such patterns. The study is based on a detailed and extensive survey at a regional scale on a tideless rocky shore. Benthic macroflora and macrofauna of 750 relev es were described along the vertical axis of 143 transects distributed across the shoreline of Catalonia (NW Mediterranean). The Detrended Correspondence Analysis (DCA) first axis is highly related to the height on the shore: species, relev es, and assemblages grade from lower to upper height (infralittoral to supralittoral). As observed in nature, different assemblages co-occur at the same height at different sites, which is shown along DCA second axis. The abiotic variables that best explain the assemblage distribution patterns are: height (75% of the model inertia), longitude (14.6%), latitude (7.2%) and transect slope (2.9%). The Canonical Correspondence Analysis (CCA) first axis is related to height on the shore and explains four times more variance than CCA second axis, which is related to the horizontal gradient. Generalized Lineal Model (GLM) results show that height on the shore is the factor explaining most of the variance in species presence. Most studied species show distribution patterns related to latitude and longitude, but always in a much smaller proportion than to height., Financial support for this work was provided by projects “Cartography of the littoral habitats of Catalonia” (Departament de Medi Ambient & Institut Cartogr afic, Generalitat de Catalunya), GRACCIE (C5D2007-00067), CoCoNET (FP7 Grant Agreement: 287844) and INTRAMURAL CSIC 201330E065. Emma Cebrian was involved in the writing and acquisition of the project and provided initial support.

12 páginas, 9 figuras, 1 tabla., Studies aimed at describing habitats and mapping their distributions are pivotal to implementing management plans and to effectively guide conservation measures. We developed a novel approach of data collection and entry (CAT-LIT) to establish a detailed cartography of the littoral habitats found along the Catalan coast (Spain). Field data were recorded using coded, two-digit hierarchical lists (e.g. Aa, Ab, etc.) of horizons found at each point along the coast, called catenas. The horizons were either dominated by species (on the rocky bottoms) or sediment types (on the beaches) and corresponded to LPRE, EUNIS and CORINE habitats. Catenas were transferred into a database and calculations about the extent of bottom types, habitats, and catenas themselves along the coast were carried out with GIS tools. In addition, habitat link richness was calculated and represented using network analysis programs. The application of CAT-LIT to the Catalan coast showed that the habitats dominated by the lichen Verrucaria amphibia and the flattened barnacle Euraphia depressa and those dominated by the barnacle Chthamalus spp. were almost ubiquitous. Those dominated by the red alga Corallina elongata, the mussel Mytilus galloprovincialis and the red alga Rissoella verruculosa were also common. Because of the frequency of their connections, those habitats formed a huge hub of links in the networks. By using catenas, the habitats can be viewed using GIS based programs keeping the catena as the main informational and ecological unit. The catenas allow maximum compactness when vertically distributed habitats are to be shown on a 2D map. The complete cartography and dataset on the spatial distribution of the littoral habitats from Catalonia is valuable for coastal management and conservation to study changes in the habitat distribution and relate such changes to anthropogenic pressures. Furthermore, the CAT-LIT can be easily adapted to shores of other seas and oceans to obtain accurate cartographies of the spatiallyreduced and highly vulnerable littoral habitats., Financial support came from the projects “Cartografia dels H abitats Litorals a Catalunya” (Departament de Territori i Sosteniblitat and Institut Cartogr afic, Generalitat de Catalunya) and INTRAMURAL CSIC 201330E065. This study is also a contribution of GRACCIE (C5D2007-00067) and CoCoNET (FP7 Grant Agreement: 287844) projects.