Search

Research in marine Spanish waters are focused on several actions to achieve an effectively management on protected areas, with the active participation of the stakeholders and research as basic tools for decision-making. Among these actions, there is one about the knowledge and control on NIS. One of its objectives is the creation of NIS factsheets, which are going to be added to the National Marine Biodiversity Geographical System (GIS) providing complementary information about taxonomic classification, common names, taxonomic synonyms, species illustrations, identification morphological characters, habitat in the native and introduced regions, biological and ecological traits, GenBank DNA sequences, world distribution, first record and evolution in the introduced areas, likely pathways of introduction, effects in the habitats and interaction with native species, and potential management measures to apply. The database will also provide data for (1) the European online platforms, (2) the environmental assessment for the Descriptor 2 (D2-NIS) of the EU Marine Strategy Framework Directive (MSFD), as well as (3) supporting decisions made by stakeholders. It is the result of extensive collaboration among scientist, manager’s and citizen science in the Spanish North-Atlantic, South-Atlantic, Gibraltar Strait-Alboran, Levantine-Balearic and Canary Islands marine divisions, providing an updated overview of the spatial distribution of relevant extended and invasive NIS of recent and established NIS introduced by maritime transport and aquaculture pathways, as well as on cryptogenic or native species in expansion due to the climatic water warming trend.

Particulate wastes (uneaten feed and faeces) are assumed to cause the most intense impact on the benthic community beneath aquaculture cages. Settling velocity of uneaten feed pellets and faecal material, required as model input data, represents a key parameter for waste dispersion models. In this study, settling velocity rates of two commercial meagre (Argyrosomus regius) feed pellets (EFICO Sigma 578 — Biomar 9 and 12 mm) and faecal material from two size categories of cultured meagre (small: 0.821 ± 0.157 kg; large: 1.663 ± 0.371 kg) were determined. Settling velocity for Biomar 9 and 12 pellets followed a normal distribution, with mean values of 9.83 ± 0.17 cm s−1 (n = 78) and 9.67 ± 0.28 cm s−1 (n = 76) respectively and 9.75 ± 0.24 cm s−1 for all data (n = 154). On the contrary, faecal particle settling velocity data did not comply with normal distribution assumptions. Settling rates were not significantly different (P = 0.37) between the two meagre size categories, but significant variation (P b 0.001) in settling velocity between all interval categories was found. Settling velocities generally increase with particle size. Particles with slow settling velocities (b1 cm s−1 ) dominated samples (87.0%) and fast settling velocities (2–3 cm s−1 ) were uncommon, with values of 1.1%. Yet, particles with small settling velocities (b1 cm s−1 ) only account for 38% of the mass. Particles with medium settling velocities (1–2 cm s−1 ), in which frequency distribution was much lower (12%) had the highest mass distribution, 51%. Waste dispersion modelling scenarios based on specific meagre settling feed and faeces settling velocity data, resulted in a wider dispersion area and lower flux values, hence in a smaller severity of predicted deposition, when compared with model output scenarios based on non-specific sea bass (Dicentrarchus labrax) and sea bream (Sparus aurata) settling velocity data.

The determination of the resilience of benthic assemblages is a capital issue for the off-shore aquaculture industry in its attempts to minimize environmental disturbances. Experimental studies are an important tool for the establishment of thresholds for macrofaunal assemblages inhabiting sandy seabeds. An experiment was conducted with three treatments (Control, 1x and 3x),in which organic load (fish pellets) was added (1x (10 g of fish pellets) and 3x (30 g)). A reduction in abundance of individuals and species richness was found as between the control and organic-enriched treatments. Significant changes in assemblage structure were also found, mainly due to the decrease of the sensitive tanaid Apseudes talpa in organically-enriched treatments. AMBI and M-AMBI indices were calculated and a decrease of ecological status was observed in treatment 3x.

A report on the conditions and the spatial distribution of the assemblages of an intertidal limpet Patella candei D´Orbigny, 1840 is presented. The study of this species, classified as a species in danger of extinction, was carried out in order to take steps about its recovery and preservation. This dangerous situation, due to the shellfish exceedings of the canarian limpet species, has caused an important decrease in their assemblages. A total of 3 617 specimens of Patella candei were found around the littoral of Fuerteventura and Lobos islet. The best structured assemblages were located in areas far away from centres of population, Monumento Natural de los Cuchillos de Vigán in the east, Parque Natural de Jandía in the south., Se realiza un estudio sobre el estado y la distribución espacial de las poblaciones de la lapa intermareal Patella candei D'Orbigny, 1840, catalogada como especie en peligro de extinción, para aportar información y establecer medidas adecuadas para su recuperación y conservación. Esta crítica situación, consecuencia de la sobreexplotación marisquera de las especies de lapas en Canarias, ha provocado una disminución alarmante de sus efectivos. Se cartografiaron 3 617 ejemplares de P. candei en todo el litoral de Fuerteventura y del islote de Lobos. Las poblaciones mejor estructuradas se encontraron en áreas situadas lejos de núcleos urbanos, como son el Monumento Natural de los Cuchillos de Vigán, en la vertiente este, y el Parque Natural de Jandía, en el sur.