5 research outputs found
Determination of phthalic acid esters and di(2-ethylhexyl) adipate in fish and squid using the ammonium formate version of the QuEChERS method combined with gas chromatography mass spectrometry
In the present study, the ammonium formate version of the QuEChERS method, considered highly advantageous
in relation to instrument maintenance and other issues, was applied for the first time to extract a group of twelve
phthalic acid esters (PAEs, i.e. dipropyl phthalate, DPP; diisobutyl phthalate, DIBP; dibutyl phthalate, DBP;
diisopentyl phthalate, DIPP; di-n-pentyl phthalate, DNPP; dihexyl phthalate, DHP; butyl benzyl phthalate, BBP;
dicyclohexyl phthalate, DCHP; di(2-ethylhexyl) phthalate, DEHP; di-n-octyl phthalate, DNOP; diisononyl
phthalate, DINP; and diisodecyl phthalate, DIDP) and one adipate (di(2-ethylhexyl) adipate, DEHA) from two
species of fish (Scomber colias and Katsuwonus pelamis) and one of squid (Loligo gahi). The method was validated
in terms of linearity, trueness and matrix effects. Determination coefficients (R2
) for matrix-matched calibration
curves were higher than 0.99 in all cases, being the lowest calibration levels in the range 0.5–10 ng/g. Mean
recovery values were between 70 and 117% with relative standard deviation values ≤20%. Matrix effects were
soft (between − 20 and +20%) for most analytes and matrices, except in squid samples, which was mostly
medium with a moderate ion suppression. The analysis of 10 samples of each type showed the presence of DIBP,
DBP and DEHP at concentrations up to 44.2 ± 2.1 ng/g of wet weight in some of the samples and species, still not
representing concerning values when considering the daily intake of such species of seafood in the human diet
(tolerable daily intake -TDI- values were not exceeded). Results demonstrated that the ammonium formate
version of the QuEChERS method can be applied with success for the extraction and determination of the selected
PAEs and DEHA in fish and squid samples.info:eu-repo/semantics/publishedVersio
Seasonal variation in microplastics and zooplankton abundances and characteristics: the ecological vulnerability of an oceanic island system
The ingestion of microplastics (MPs - plastic particles <5 mm) by planktivorous organisms represents a signif icant threat to marine food webs. To investigate how seasonality might affect plastic intake in oceanic islands'
ecosystems, relative abundances and composition of MPs and mesozooplankton samples collected off Madeira
Island (NE Atlantic) between February 2019 and January 2020 were analysed. MPs were found in all samples,
with fibres accounting for 89 % of the particles. MPs and zooplankton mean abundance was 0.262 items/m3 and
18.137 individuals/m3
, respectively. Their monthly variations follow the seasonal fluctuation of environmental
parameters, such as currents, chlorophyll-a concentration, sea surface temperature and precipitation intensity. A
higher MPs/zooplankton ratio was recorded in the warm season (May-Oct), reaching 0.068 items/individual
when considering large-sized particles (1000–5000 μm). This is the first study to assess the seasonal variability of
MPs in an oceanic island system providing essential information respecting its ecological impact in pelagic
environments.info:eu-repo/semantics/publishedVersio
Behavioural Ecology Traits of Elusive Deep-Diver Whales Unravel a Complex Social Structure Influenced by Female Philopatry and Defence Polygyny
Knowledge of the role of individual associations has provided an insightful understanding of the structures of animal societies, especially in highly social mammals such as primates. Yet, this is unbalanced towards marine mammals, particularly to beaked whales, due to their elusive nature. In addition, information on the fundamental drivers of the social structure of these deep-diving animals is still scarce. Here, the hypothesis of female defence polygyny was tested in Blainville’s beaked whales (Mesoplodon densirostris) and discussed within the context of marine and terrestrial organisms displaying similar patterns, by (i) estimating residency times to obtain information on the movements into and out of the area, (ii) analysing social networks to assess individual association metrics, (iii) measuring the strength of the associations to assess the existence of preferred or avoided relationships among individuals, and (iv) modelling different social structures to address temporal patterns in social relationships. Using a 9-year photographic dataset derived from the pelagic habitat, individual associations were inferred based on likelihood techniques. This approach allowed to infer on the species’ social structure in relation to age class, sex, residency status, and spatio-temporal patterns, which can be a good practice to be applied for other taxa. Heterogeneity in capture probability and residency times was observed between age-sex classes, with adult females exhibiting long-term site fidelity. This suggests different habitat roles and spatial structuring within this social organisation. Strong and long dyadic associations occurred between adult females and immatures, contrarily to between males, and the best-fitting models of the temporal patterns suggested long-lasting and temporary associations. The present findings unravel a complex social structure stratified by age-sex class and influenced by female philopatry and defence polygyny, like an unimale group mating system, which varies from other beaked whales but is similar to some birds, pinnipeds, or non-human primates.FUNDING: The Oceanic Observatory of Madeira and the Portuguese Foundation for Science and Technology (FCT) throughout the strategic projects M1420-01-0142-FEDER-000001 and UIDB/04292/2020, respectively. AB was supported by a MARE grant throughout the project UIDB/04292/2020, AD by ARDITI throughout the project M1420-09-5369-FSE-000002, RF by the FCT grant SFRH/BD/147225/2019, AS by the FCT grant SFRH/BD/141609/2018, MF by the MAC2/1.1a/385 in the framework of INTERTAGUA (MAC INTERREG 2014-2020), and FA by the FCT project UIDP/04292/2020 granted to MARE.info:eu-repo/semantics/publishedVersio
Large-scale movements of common bottlenose dolphins in the Atlantic : dolphins with an international courtyard
Wide-ranging connectivity patterns of common bottlenose dolphins (Tursiops truncatus) are generally poorly known worldwide and more so within the oceanic archipelagos of Macaronesia in the North East (NE) Atlantic. This study aimed to identify long-range movements between the archipelagos of Macaronesia that lie between 500 and 1,500 km apart, and between Madeira archipelago and the Portuguese continental shelf, through the compilation and comparison of bottlenose dolphin's photo-identification catalogues from different regions: one from Madeira (n = 363 individuals), two from different areas in the Azores (n = 495 and 176), and four from different islands of the Canary Islands (n = 182, 110, 142 and 281), summing up 1791 photographs. An additional comparison was made between the Madeira catalogue and one catalogue from Sagres, on the southwest tip of the Iberian Peninsula (n = 359). Results showed 26 individual matches, mostly between Madeira and the Canary Islands (n = 23), and between Azores and Madeira (n = 3). No matches were found between the Canary Islands and the Azores, nor between Madeira and Sagres. There were no individuals identified in all three archipelagos. The minimum time recorded between sightings in two different archipelagos (≈ 460 km apart) was 62 days. Association patterns revealed that the individuals moving between archipelagos were connected to resident, migrant and transient individuals in Madeira. The higher number of individuals that were re-sighted between Madeira and the Canary Islands can be explained by the relative proximity of these two archipelagos. This study shows the first inter-archipelago movements of bottlenose dolphins in the Macaronesia region, emphasizing the high mobility of this species and supporting the high gene flow described for oceanic dolphins inhabiting the North Atlantic. The dynamics of these long-range movements strongly denotes the need to review marine protected areas established for this species in each archipelago, calling for joint resolutions from three autonomous regions belonging to two EU countries.Partnership Program (US) and project ‘‘Cetáceos, Oceanografía y Biodiversidad de las Aguas Profundas de La Palma y El Hierro’’ funded by ‘‘Ministerio de Ciencia e Innovación’’ of the Spanish Government, grant number CETOBAPH-CGL2009-1311218 supported the work in the Canary Island. In Madeira, this study was supported by the Oceanic Observatory of Madeira through the project M1420-01-0142-FEDER-000001 and by the Portuguese Foundation for Science and Technology through the strategic project UID/MAR/04292/2020. Ana Dinis and Filipe Alves have grants funded by ARDITI— Madeira’s Regional Agency for the Development of Research, Technology and Innovation, throughout the project M1420-09- 5369- FSE- 000002, and Annalisa Sambolino is supported by the Portuguese Foundation for Science and Technology through the PhD grant number SFRH/BD/1416092018. In Azores, the MONICET platform is supported by project MEEMO (ACORES-01-0145-FEDER-000079) and Marta Tobena is supported by a PhD grant (M31a/F/0722015). There was no additional external funding received for this study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio
NAPTRAM - Plastiktransportmechanismen, Senken und Interaktionen mit Biota im Nordatlantik / NAPTRAM - North Atlantic plastic transport mechanisms, sinks, and interactions with biota, Cruise No. SO279, Emden (Germany) – Emden (Germany), 04.12.2020 – 05.01.2021
The coastal and open oceans represent a major, but yet unconstrained, sink for plastics. It is likely
that plastic-biota interactions are a key driver for the fragmentation, aggregation, and vertical
transport of plastic litter from surface waters to sedimentary sinks. Cruise SO279 conducted
sampling to address core questions of microplastic distribution in the open ocean water column,
biota, and sediments. Seven stations were sampled between the outer Bay of Biscay and the
primary working area south of the Azores. Additional samples were collected from surface waters
along the cruise track to link European coastal and shelf waters with the open ocean gyre.
Microplastic samples coupled with geochemical tracer analyses will build a mechanistic
understanding of MP transport and its biological impact reaching from coastal seas to the central
gyre water column and sinks at the seabed. Furthermore, floating plastics were sampled for
microbial community and genetic analyses to investigate potential enzymatic degradation
pathways. Cruise SO279 served as the third cruise of a number of connected research cruises to
build an understanding of the transport pathways of plastic and microplastic debris in the North
Atlantic from the input through rivers and air across coastal seas into the accumulation spots in
the North Atlantic gyre and the vertical export to its sink at the seabed. The cruise was an
international effort as part of the JPI Oceans project HOTMIC (“HOrizontal and vertical oceanic
distribution, Transport, and impact of MICroplastics”) and the BMBF funded project PLASTISEA
(‘Harvesting the marine Plastisphere for novel cleaning concepts’), and formed a joint effort of
HOTMIC and PLASTISEA researchers from a range of countries and institutes