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We report a georeferenced dataset of a biological survey carried out in lakes and reservoirs in Piedmont and Sardinia regions (Italy), that includes fish fauna, macroinvertebrates, macrophytes, and phytoplankton. This survey was carried out to test the standardised protocols adopted with the National Decree 260/210 by the Italian Ministry of the Environment, Land and Sea for the assessment of the ecological status of lakes and the ecological potential of reservoirs for satisfying the requirements of the European Water Framework Directive (WFD) 2000/60/EC. Occurrence data have been uploaded to the Global Biodiversity Information Facility (GBIF).

A profound transformation, in recent decades, is promoting shifts in the ways ecological science is produced and shared; as such, ecologists are increasingly encouraged to engage in dialogues with multiple stakeholders and in transdisciplinary research. Among the different forms of public engagement, citizen science (CS) has significant potential to support science-society interactions with mutual benefits. While many studies have focused on the experience and motivations of CS volunteers, scarce literature investigating the perspectives of researchers is available. The main purpose of this paper is to better understand scientists’ attitudes about CS in the context of its potential to support outcomes that extent beyond more traditional ones focused on promoting science knowledge and interest. We surveyed the scientific community belonging to the International Long-Term Ecological Research (ILTER) network because ILTER is of interest to multiple stakeholders and occurs over long time scales. Via an online questionnaire, we asked ILTER scientists about their willingness to participate in different types of public engagement, their reasons for participating in CS, the associated barriers, and any impacts of these efforts on them. Our findings show that many ILTER scientists are open to participating in CS for a wide range of reasons; the dominant ones involve deeper public engagement and collaboration. The barriers of greatest concern of these respondents were the lack of institutional support to start and run a CS project and the difficulty of establishing long-term stable relationships with the public. They reported impacts of CS activities on how they pursue their work and acknowledged the benefit of opportunities to learn from the public. The emerging picture from this research is of a community willing and actively involved in many CS projects for both traditional reasons, such as data gathering and public education, and expanded reasons that activate a real two-way cooperation with the public. In the ILTER community, CS may thus become an opportunity to promote and develop partnerships with citizens, helping to advance the science-society interface and to rediscover and enhance the human and social dimension of the scientific work.

In the last decades, citizen science (CS) has experienced an increasing interest as a practice in which scientists and citizens collaborate to produce new knowledge for science, society and policy. Environmental and ecological sciences are among the most active in proposing CS activities and new models for citizen participation in research. In addition to environmental dimensions, these fields necessarily include social and cultural dimensions to confront the complex local and global environmental challenges. This is particularly evident in the International Long-Term Ecological Research (ILTER) network, where the integration of social sciences has become a recognized priority. ILTER offers a valuable landscape to explore common CS features across a wide range of different cultural and socio-ecological contexts, as well as worldviews of science-society interactions. In 2020, we surveyed scientists working at ILTER sites across the globe to identify key features of CS initiatives in which they are/were involved and the levels of participation of the volunteers. We consider these features in the context of the internationally-developed “Ten Principles of Citizen Science” by examining scientific outcomes and societal/policy impact, type of volunteers’ involvement, and sharing of data/findings and feedbacks and acknowledging volunteers. Our results indicate that the ILTER community demonstrated a good predisposition toward environmentally-focused CS initiatives with diverse scientific questions including biodiversity, water quality, ecosystem services and climate change. Most of the respondents reported that the volunteers were involved mainly in collecting samples or recording data; some other activities, such as dissemination of the project conclusions and discussion and translation of the results into action, were also mentioned. Volunteers were usually trained for these initiatives and acknowledged in peer-reviewed publication, however data from the initiatives were only partially shared openly. We conclude with remarks and suggestions for expanding design and implementation of CS in the ILTER community.

In this paper we describe a 25-year (1986-2010) dataset of phytoplankton cell density abundance and biovolume in Lake Candia, a eutrophic, natural, small, and shallow lake located in north-western Italy, with data that are made available through the GBIF repository. The lake belongs to the national (LTER-Italy), European (LTER-Europe) and International (ILTER) long-term ecological research (LTER) networks. Phytoplankton samples were collected approximately monthly at the maximum depth station of the lake (7.7 m) and analysed with the inverted microscope, estimating both the cell density abundance and biovolume of each taxon. The dataset includes 10,120 georeferenced occurrences related to 545 taxa. During this 25-year period, the lake underwent profound modifications mainly related to the lake biomanipulation activities addressed to the management of aquatic macrophyte and to the evolution of the trophic condition. Making this dataset available represents a contribution to the current activities of the LTER networks for defining and reconstructing spatial and temporal dynamics and to identify and compare reliable trends.

This Policy Brief succinctly presents the Ecological Observing System of the Adriatic Sea (ECOAdS), aimed at integrating the ecological and oceanographic dimensions within the conservation strategy of the Natura 2000 network, and to propose a way to go for its future development and maintenance. After a definition of marine ecological observatories, we describe the current structure of ECOAdS, its key components and potential relevance in relation to the main European strategies for biodiversity and marine observation for the next decade. Finally, we suggest some actions that could be undertaken for the future development of ECOAdS, targeting possible perspectives in different regional, macro-regional, national and European strategic contexts. This Policy Brief is one of the outcomes of the Interreg Italy-Croatia Project ECOSS (ECological Observing System in the Adriatic Sea: oceanographic observations for biodiversity; https://www.italy-croatia.eu/web/ecoss), which had the main purpose to design and carry out the first steps for the establishment of ECOAdS.

Implementing effective marine monitoring to detect and track ecosystem shifts, biodiversity alteration, and habitat loss is one of the most crucial challenges to meet the objectives set out by the Post-2020 Biodiversity Framework and by the United Nations Sustainable Development Goals. The lack of coordinated and harmonized monitoring frameworks at different spatial scales and their weakness in accounting for ecological processes, due to incomplete sets of monitoring variables, strongly hinder the achievement of conservation objectives. Here, we propose an approach to build a coherent ecosystem-based system of monitoring variables for target marine species and habitats. The approach is designed to integrate the existing monitoring frameworks set up by the Water and the Marine Strategy Framework directives, and the Essential Ocean and Biodiversity Variables, with the aim to contribute to their harmonization and implementation. Furthermore, by embracing a holistic vision, it aims to incorporate ecological processes and socio-ecological aspects, considering the benefits of public engagement through citizen science, and of the ecosystem services approach for policies’ implementation. The study stems from the Ecological Observing System of the Adriatic Sea (ECOAdS), which was developed in the framework of the Interreg Italy-Croatia project ECOSS, using as exemplary monitoring test cases two relevant conservation targets for Natura 2000 sites of the Adriatic Sea, the common bottlenose dolphin and seagrass meadows. We test the potential of this approach in guiding the prioritization of monitoring variables under ecosystem-based criteria, and provide insights into the benefits delivered by an integrated system of observatories’ networks and monitoring frameworks to support marine conservation at both local and regional scales. The proposed approach can be transferred to other contexts and scales to help build a common knowledge and monitoring framework for conservation and management strategies, saving costs by relying on available resources and on consolidated and long-lasting approaches that might converge towards global initiatives.

Essential Biodiversity Variables (EBVs) and Biological and Ecosystem Essential Ocean Variables (BioEco EOVs) are two cooperative conceptual frameworks which help harmonize and process multi-source marine biodiversity observations into robust indexes, in order to measure progress toward policy conservation goals. Long-term monitoring networks are encouraged to contribute to these frameworks by mobilizing historical times series which are suitable for detecting impacts of management policies. In this paper, we identify specific recommendations for increasing reuse in the EV frameworks of the biodiversity historical data collected and maintained by the Gulf of Venice (GOV) site, i.e., the monitoring facility that is selected as case study in the Italian Long-Term Ecological Research network (LTER-Italy). The recommendations are obtained through a practical approach comprising two phases. In the first phase, a literature review helps extract the guidelines for implementing the principles representing the most recent attempt to unify management of EBV and BioEco EOV data, i.e., Benson’s tenets. In the second phase, we compare the guidelines to the data management practices enacted by the selected monitoring site in order to recommend curation interventions. The outputs of the analysis are discussed in order to verify if the approach and the recommendations are general enough to be replicated in the marine component of monitoring networks to coordinate the LTER data contribution to the EV frameworks.

The design and establishment of Marine Ecological Observatories (MEOs) are fostered at the European level. MEOs should adopt a holistic view, integrating and harmonizing long-term oceanographic and ecological research and monitoring, and increasing conservation strategies effectiveness according to the ecological connectivity concept. The data and knowledge collected and made available through MEOs should inform policies dealing with conservation and management of the marine environment. We present and discuss these issues in the Adriatic Sea context, where the transnational ecological observatory “ECOAdS” is under development in the framework of the Interreg Italy-Croatia project ECOSS (Observing System in the Adriatic Sea: oceanographic observations for biodiversity), which aims to support Natura 2000 network implementation and cross-border coordination of multiple monitoring initiatives. We analyse the main EU directives that deal with marine conservation, notably the Habitats and Birds directives, the Water Framework Directive, and the Marine Strategy Framework Directive, as they are the primary instruments that can guide the development of the observatory while strengthening cooperation at the basin scale. We bring out the synergies and discrepancies among these legal instruments, and build on them ECOAdS as a monitoring platform that may respond and contribute to their requirements, boosting the synergies and overcoming the weaknesses. Finally, we provide some hints for the further development of this transnational MEO as a collector of the existing monitoring efforts aimed at harmonizing their approaches and incorporating the ecological connectivity to foster an ecosystem-based approach to conservation management.

This work presents a practical case study of the Open Science principles applied to the valorization of a long-term marine dataset collected in the Northern Adriatic Sea, one of the Long-Term Ecological Research (LTER) sites of the LTER-Italy network. The dataset covers a temporal range of 50 years (1965–2015), and it is composed of abiotic, and phyto- and zooplankton data, for a total of 21 parameters. The case study involved many actions, which will be described here, distinguishing between the ones affecting the whole research project workflow and those acting more specifically on the dataset. We evaluate strengths, weaknesses, and possible improvements for each action. The present study pointed out that, despite the initial and still some remaining mistrust, opening research projects is more than a best practice. It is (i) important because it improves research transparency (increasing researchers’ credibility, replicability of science, and products reuse), (ii) required by many international initiatives and regulations, and (iii) enriching because it encourages cooperation between scientists across different fields and laboratories.

The conceptual framework of Essential Biodiversity Variables (EBVs) aims to capture the major dimensions of biodiversity change by structuring biodiversity monitoring and by ruling data collection amongst different providers. Amongst the research infrastructures adopting and implementing the EBV framework, LTER-Europe - the European node of ILTER (International Long-Term Ecological Research) - follows the approach to compare site-based biodiversity observations within and across its networks. However, a synoptic overview of their contributions with EBVs-relevant data is still missing, since data are not made available for several reasons. In this paper, we assess the capacity of LTER-Italy, one of the richest and heterogeneous networks of LTER sites in Europe, to provide data to “Species Distribution” and “Species Abundance” EBVs without inspecting and downloading their contents. To this aim, we mine the EBVs information which is publicly structured and shared by LTER site managers through DEIMS-SDR, the LTER-Europe online metadata repository. We classify the sites according to two types of contributions: (i) the actual contribution, based on metadata of datasets and (ii) the potential contribution, based on metadata of sites. Through these assessments, we investigate if LTER-Italy monitoring activities can provide EBVs measures and which sites currently provide datasets. By comparing the two contributions, we pinpoint the factors hampering the accessibility of LTER-Italy data and suggest solutions to increase the discoverability and reusability of LTER-Italy EBVs measurements. The research provides the first overview of EBVs monitored in LTER-Italy and the corresponding data management practices, as well as an evaluation of the interoperability of this network with respect to other research organisations for legal and technical aspects.

Collected harmonized data on global litter decomposition are of great relevance for scientists, policymakers, and for education of the next generation of researchers and environmental managers. Here we describe the TeaComposition initiative, a global and open research collaborative network to study organic matter decomposition in a standardized way allowing comparison of decomposition rate and carbon turnover across global and regional gradients of ecosystems, climate, soils etc. The TeaComposition initiative today involves 570 terrestrial and 300 aquatic ecosystems from nine biomes worldwide. Further, we describe how to get involved in the TeaComposition initiative by (a) implementing the standard protocol within your study site, (b) joining task forces in data analyses, syntheses and modelling efforts, (c) using collected data and samples for further analyses through joint projects, (d) using collected data for graduate seminars, and (e) strengthening synergies between biogeochemical research and a wide range of stakeholders. These collaborative efforts within/emerging from the TeaComposition initiative, thereby, will leverage our understanding on litter decomposition at the global scale and strengthen global collaborations essential for addressing grand scientific challenges in a rapidly changing world.

The sharing of research data allows for information reuse and knowledge advancement but its realization is often a challenge and seldom successful in practice. We propose a workflow for the design of a User Support System (USS) aimed at tutoring research groups in data sharing by considering their social and domain backgrounds. Our engagement approach focuses on multidisciplinary geospatial research, particularly when interoperable data sharing is required. Specifically, we first characterize the research community on the basis of the behavior and competences in data management by its groups and then target the needs of the latter with specific facilities. We address for the first time in literature the issue of modeling research groups as targets of the USS and provide a roadmap to standardize USS activities across different communities. We describe the implementation of the workflow in the context of an Italian research project and we assess the impact of the USS in terms of increase in the number of nodes and resources in the project’s data infrastructure, and of fulfilment of the expectations by the research groups.

EDI is a general purpose, template-driven metadata editor for creating XML-based descriptions. Originally aimed at defining rich and standard metadata for geospatial resources, It can be easily customised in order to comply with a broad range of schemata and domains. EDI creates HTML5 [9] metadata forms with advanced assisted editing capabilities and compiles them into XML files. The examples included in the distribution implement profiles of the ISO 19139 standard for geographic information [14], such as core INSPIRE metadata [10], as well as the OGC [8] standard for sensor description, SensorML [11]. Templates (the blueprints for a specific metadata format) drive form behaviour by element data types and provide advanced features like codelists1 underlying combo boxes or autocompletion functionalities. Virtually, the editing of any metadata format can be supported by creating a specific template. EDI is stored on GitHub at https://github.com/SP7-Ritmare/EDI-NG_client and https://github.com/SP7-Ritmare/EDI-NG_server.

We present a data set on the biodiversity of Italian freshwaters, including lakeshores and riverbanks of natural (N=379: springs, streams and lakes) and artificial (N=11: fountains) sites. The data set belongs partly to the Italian Long Term Ecological Research network (LTER-Italy) and partly to LifeWatch, the European e-Science infrastructure for biodiversity and ecosystem research. The data included cover a time period corresponding to the last fifty years (1962-2014). They span a large number of taxa from prokaryotes and unicellular eukaryotes to vertebrates and plants, including taxa linked to the aquatic habitat in at least part of their life cycles (like immature stages of insects, amphibians, birds and vascular plants). The data set consists of 6463 occurrence data and distribution records for 1738 species. The complete data set is available in csv file format via the LifeWatch Service Centre.

Geospatial metadata are often encoded in formats that either are not aimed at efficient retrieval of resources or are plainly outdated. Particularly, the quantum leap represented by the Semantic Web did not induce so far a consistent, interlinked baseline in the geospatial domain. Datasets, scientific literature related to them, and ultimately the researchers behind these products are only loosely connected; the corresponding metadata intelligible only to humans, duplicated in different systems, seldom consistently. We address these issues by relating metadata items to resources that represent keywords, institutes, researchers, toponyms, and virtually any RDF data structure made available over the Web via SPARQL endpoints. Essentially, our methodology fosters delegated metadata management as the entities referred to in metadata are independent, decentralized data structures with their own life cycle. Our example implementation of delegated metadata envisages: (i) editing via customizable web-based forms (including injection of semantic information); (ii) encoding of records in any XML metadata schema; and (iii) translation into RDF. Among the semantics-aware features that this practice enables, we present a worked-out example focusing on automatic update of metadata descriptions. Our approach, demonstrated in the context of INSPIRE metadata (the ISO 19115/19119 profile eliciting integration of European geospatial resources) is also applicable to a broad range of metadata standards, including non-geospatial ones.

This study reports the first preliminary results of the DYRESM-CAEDYM model application to a mid size sub-alpine lake (Lake Pusiano North Italy). The in-lake modelling is a part of a more general project called Pusiano Integrated Lake/Catchment project (PILE) whose final goal is to understand the hydrological and trophic relationship between lake and catchment, supporting the restoration plan of the lake through field data analysis and numerical models. DYRESM is a 1D-3D hydrodynamics model for predicting the vertical profile of temperature, salinity and density. CAEDYM is multi-component ecological model, used here as a phytoplankton-zooplankton processes based model, which includes algorithms to simulate the nutrient cycles within the water column as well as the air-water gas exchanges and the water-sediments fluxes. The first results of the hydrodynamics simulations underline the capability of the model to accurately simulate the surface temperature seasonal trend and the thermal gradient whereas, during summer stratification, the model underestimates the bottom temperature of around 2 °C. The ecological model describes the epilimnetic reactive phosphorus (PO4) depletion (due to the phytoplankton uptake) and the increase in PO4 concentrations in the deepest layers of the lake (due to the mineralization processes and the sediments release). In terms of phytoplankton dynamics the model accounts for the Planktothrix rubescens dominance during the whole season, whereas it seems to underestimate the peak in primary production related to both the simulated algal groups (P. rubescens and the rest of the other species aggregated in a single class). The future aims of the project are to complete the model parameterization and to connect the in-lake and the catchment modelling in order to gain an integrated view of the lake-catchment ecosystem as well as to develop a three dimensional model of the lake.

The limnological evolution of Lake Pusiano followed, starting 1970s, an increasing eutrophication process, attaining the maximum trophic level at the mid 1980s, when the lake reached an hypertrophic condition (around 200 μg P l-1 at winter overturn). Between mid 1980s and the beginning of this century, the phosphorus concentrations continuously decreased, until reaching TP values close to 60 μg P l-1. Despite this improvement in trophic conditions, since 1994 the cyanobacteria contribution increased: noticeable was a very intense bloom of Planktothrix rubescens, occurred during autumn 2001. The following year, when we carried out this research, this filamentous cyanobacterium strongly dominated the phytoplankton population for the whole seasonal cycle. However, after an intense flood occurred in November the P. rubescens population decreased again. This paper aims at describing the seasonal dynamics of the cyanobacterium P. rubescens in Lake Pusiano (North Italy) during year 2002, pointing out the environmental factors which favoured its large dominance during the whole seasonal cycle: particular attention will be paid to the role played by the physical factors in promoting the growth of P. rubescens, despite the nutrient reduction. Our experimental evidences suggest the involment of mechanisms already observed in other European lakes, such as the establishment of a metalimnetic niche. Moreover, our data point out a high sensitivity of this environment to the changes of the hydrological regime, which probably affect the seasonal phytoplankton dynamics.

Underwater light regime is widely considered the principal determinant of aquatic plant depth distribution. The majority of previous studies dealing with macrophytes in lakes have singled out Secchi disk transparency (SD) values as the key empirical proxy to explain the maximum depth of macrophyte colonization (Zc). Few studies have investigated the role played by lake morphometry in structuring macrophyte beds. Using a balanced dataset including 20 Italian lakes (10 shallow and 10 deep lakes), we analysed transparency and lake morphometric traits to investigate their possible effects on Zc. Our results demonstrate that lake area plays a significant role, and confirm a direct influence of SD values on Zc. Considering lakes with an equal degree of transparency, smaller lakes may yield a lower Zc than larger ones. Morphology has a great influence on lake ecological characteristics especially on water thermal conditions and mixing depth. Based on our data, we argue that the thermal stratification plays a non negligible role in explaining macrophytes zonation, due to its influence on macrophytes life cycles and phytoplankton vertical distribution. Therefore, the present data suggest the need to enhance and refine our knowledge about the relationship between aquatic plants distribution and lake thermal conditions to better model the response of macrophytes to climate change and eutrophication.

Metadata management is an essential enabling factor for geospatial assets because discovery, retrieval, and actual usage of the latter are tightly bound to the quality of these descriptions. Unfortunately, the multi-faceted landscape of metadata formats, requirements, and conventions makes it difficult to identify editing tools that can be easily tailored to the specificities of a given project, workgroup, and Community of Practice. Our solution is a template-driven metadata editing tool that can be customised to any XML-based schema. Its output is constituted by standards-compliant metadata records that also have a semantics-aware counterpart eliciting novel exploitation techniques. Moreover, external data sources can easily be plugged in to provide autocompletion functionalities on the basis of the data structures made available on the Web of Data. Beside presenting the essentials on customisation of the editor by means of two use cases, we extend the methodology to the whole life cycle of geospatial metadata. We demonstrate the novel capabilities enabled by RDF-based metadata representation with respect to traditional metadata management in the geospatial domain.

Optical satellite remote sensing represents an opportunity to integrate traditional methods for assessing water quality of lakes: strengths of remote sensing methods are the good spatial and temporal coverage, the possibility to monitor many lakes simultaneously and the reduced costs. In this work we present an overview of optical remote sensing techniques applied to lake water monitoring. Then, examples of applications focused on lake Maggiore, the second largest lake in Italy are discussed by presenting the temporal trend of chlorophyll-a (chl-a), suspended particulate matter (SPM), coloured dissolved organic matter (CDOM) and the z90 signal depth (the latter indicating the water depth from which 90% of the reflected light comes from) as estimated from the images acquired by the Medium Resolution Imaging Spectrometer (MERIS) in the pelagic area of the lake from 2003 to 2011. Concerning the chl-a trend, the results are in agreement with the concentration values measured during field surveys, confirming the good status of lake Maggiore, although occasional events of water deterioration were observed (e.g., an average increase of chl-a concentration, with a decrease of transparency, as a consequence of an anomalous phytoplankton occurred in summer 2011). A series of MERIS-derived maps (summer period 2011) of the z90 signal are also analysed in order to show the spatial variability of lake waters, which on average were clearer in the central pelagic zones. We expect that the recently launched (e.g., Landsat-8) and the future satellite missions (e.g., Sentinel-3) carrying sensors with improved spectral and spatial resolution are going to lead to a larger use of remote sensing for the assessment and monitoring of water quality parameters, by also allowing further applications (e.g., classification of phytoplankton functional types) to be developed.

Charophytes (stoneworts and bassweeds) are a typical macrophytic component of inland water ecosystems. Well-developed submerged meadows of charophytes are expression of clear water and rather low phytoplankton concentrations. Consequently, among aquatic macroscopic primary producers, charophytes are one of the most threatened groups being very sensitive to phosphorous availability, turbidity and water level perturbations. Accordingly, charophytes have been suffering a massive diversity loss worldwide over the last century, mainly because of human-induced pressures. During summer 2011, detailed field surveys were carried out with the main purpose of filling knowledge gaps concerning aquatic flora and vegetation of the lake Garda – the largest lake in Italy and one of the deepest in Europe. Along randomly selected transects, floristic data were collected following standard procedures, as imposed by the Water Framework Directive. Overall, 12 different species of charophytes were recorded, which accounts for 36% of total Italian charophytes and 19% of European species. The most diffuse species were Chara globularis and C. intermedia; whereas, the most interesting taxa were Chara polyacantha and Nitella hyalina, two species with narrow distribution in Italy. Overall in the lake Garda, dense stands of charophytes covered almost homogeneously the littoral sectors at a water depth between 3 and 12 m. The deepest species was C. globularis, which reached a maximum depth of colonisation of about 17.5 m. Charophytes represent a major element among the primary producers in the lake Garda. The high local charophyte diversity and the rather wide most colonised areas (~1000-1200 ha) confirm that the lake Garda is an important reserve for many rare and threatened charophytes. For the first time, these results highlight the key role of the lake Garda for charophyte diversity at a national and European level.

In situ and hyperspectral MIVIS (Multispectral Infrared and Visible Imaging Spectrometer) images acquired over a period of 13 years are used to assess changes in macrophyte colonization patterns in the coastal zones of the Sirmione Peninsula in the southern part of Lake Garda (Italy). In situ data (abundance, cover density and diversity of macrophyte communities) and MIVIS-derived maps of colonized substrates are analyzed by considering the variability of the main hydrological and physicochemical variables in order to indicate the main factors that explain the spatiotemporal variability of macrophyte communities. The results show a considerable modification in terms of macrophyte structural complexity and colonized areas. Almost 98% of macrophyte meadows (in particular communities with a density of over 70%) are lost and subsequently replaced by moderate to extremely rare communities with density from 10% to 40%. Well-established submerged macrophytes are replaced by de-structured communities characterized by moderate to scarce density: on average lower than 30%. The study indicates that macrophyte distribution along the littoral zone of the Sirmione Peninsula is certainly linked to water transparency and water level fluctuation. The results also indicate that the worsening of eutrophication may be associated with the gradual disappearance of macrophyte meadows, but may also be accelerated by herbivorous aquatic birds grazing there. Lastly, the increasing frequency and number of catamaran tours could be considered a threat for the stability of these valuable communities.