Sandy beach ecosystems are particularly affected by plastic pollution. Supralittoral amphipods are important components of the food web in sandy beaches and their ability to ingest microplastics and bioplastics has been assessed. Chitosan, a polysaccharide obtained by deacetylation of chitin, the second most abundant polymer in the world, represents an interesting component to produce novel bioplastics in combination with other biopolymers like starch.
View Article and Find Full Text PDFBackground: The seafood consumption and trade have increased over the years, and along its expected expansion pose major challenges to the seafood industry and government institutions. In particular, the global trade in fish products and the consequent consumption are linked to reliable authentication, necessary to guarantee lawful trade and healthy consumption. Alterations or errors in this process can lead to commercial fraud and/or health threats.
View Article and Find Full Text PDFIt is well known that the celestial polarization is used as a compass cue by many species of insects and crustaceans. Although it has been shown that the sandhopper Talitrus saltator perceives polarized light and possesses an arrangement of the rhabdomeres that could allow e-vector interpretation and utilization, T. saltator does not use the e-vector of the skylight polarization as a compass cue when making excursions along the sea-land axis of sandy shores.
View Article and Find Full Text PDFTalitrid amphipods are an important component of detritus web, playing a key role in the fragmentation of organic matters of marine and terrestrial origin, and it is well known that sandhoppers ingest microplastics. To assess the effective consumption of bioplastics and their effects on survival rate and on pollutants transfer (i.e.
View Article and Find Full Text PDFObjective: To investigate the effects of Action Observation and Motor Imagery administered the day before surgery on functional recovery in patients after total hip arthroplasty.
Design: Randomised controlled trial.
Setting: Humanitas Clinical and Research Center, Milan, Italy.
Microplastics pollution is progressively threatening natural parks across the world. In the framework of monitoring this concerning trend, the present study focuses on the occurrence and identification of mesoplastics (MEPs) and microplastics (MPs) in sand samples collected before and after the summer season from the beach of the Nature Park of Migliarino San Rossore Massaciuccoli (Pisa, Italy). Meso- and microplastics were identified using Fourier transform infrared spectroscopy 2D Imaging, and detected in all samples with average concentrations of 207 ± 30 MPs/kg d.
View Article and Find Full Text PDFThe sandhopper relies on both the sun and the moon compasses to return to the belt of damp sand on the beach in which it lives buried during the day. In addition to the sun, the gradient of radiance and the spectral distribution across the sky could provide directional information that can potentially use to orient itself during the day even when the sun is not visible (e.g.
View Article and Find Full Text PDFJ Comp Physiol A Neuroethol Sens Neural Behav Physiol
September 2020
We investigated the eye regionalization in Talitrus saltator by morphological, electrophysiological and behavioural experiments. Each ommatidium possesses five radially arranged retinular cells producing a square fused rhabdom by R1-R4 cells; the smaller R5 exists between R1 and R4. The size of R5 rhabdomere is larger in the dorsal part and becomes smaller in the median and ventral parts of the eye.
View Article and Find Full Text PDFThe presence and accumulation of plastic waste into the marine environment are well known environmental issues. Microplastics (MPs) end up in sea waters and, due to their hydrophobicity and high surface/volume ratio, POPs tend to sorb and accumulate to their surface. The supralittoral amphipod Talitrus saltator (T.
View Article and Find Full Text PDFAnimals that use astronomical cues to orientate must make continuous adjustment to account for temporal changes in azimuth caused by Earth's rotation. For example, the Monarch butterfly possesses a time-compensated sun compass dependent upon a circadian clock in the antennae. The amphipod Talitrus saltator possesses both a sun compass and a moon compass.
View Article and Find Full Text PDFTalitrid amphipods (sandhoppers and beach fleas) are typical of the supralittoral zone. They are known to thrive on stranded materials, including detrital marine angiosperms and macroalgae, as well as occasional dead animals. In this work, the gut microbiota of five species of talitrid amphipods (Talitrus saltator, Talorchestia ugolinii, Sardorchestia pelecaniformis, Orchestia montagui and Orchestia stephenseni) collected in Sardinia (Italy) has been investigated through: i) metabarcoding analysis of the amplified 16S rRNA V4 region; and ii) quantification of family 48 glycosyl hydrolase genes (GHF48), involved in cellulose degradation.
View Article and Find Full Text PDFJ Comp Physiol A Neuroethol Sens Neural Behav Physiol
January 2016
We investigate the role of the landscape in the zonal recovery of the Equatorial sandhopper Talorchestia martensii Weber. It is known that this species uses the sun and the magnetic compasses to return to the belt of damp sand of the beach following the shortest route (the sea-land axis). However, the sun is not always easy to use at Equatorial latitudes because of astronomical reasons (its zenithal culmination and its hourly azimuthal speed) at least during the central time of the day (around noon) and close to the equinox.
View Article and Find Full Text PDFJ Comp Physiol A Neuroethol Sens Neural Behav Physiol
May 2015
The influence of salt concentration in the seawater on solar orientation in Talitrus saltator and Talorchestia ugolinii was studied in a confined environment (transparent plexiglass bowls). Sodium and calcium concentrations strongly affect both sea-land orientation and the sun compass mechanism in T.saltator, whereas the behaviour of T.
View Article and Find Full Text PDFThe problem sandhoppers face when they find themselves on the dry sand is to reach as quickly as possible the belt of moist sand near the water. In the present study, I ask whether, alongside many other orienting factors, sandhoppers use the optic flow they experience to maintain their bearing relative to the sea-land axis. Adult individuals of Talitrus saltator were released in a transparent Plexiglas bowl, horizontally placed between four walls with a pattern of vertical black and white stripes.
View Article and Find Full Text PDFBull Environ Contam Toxicol
December 2012
This study evaluates the use of the sandhopper Talitrus saltator as a bioindicator of PAHs contamination of the supralittoral zone of sandy beaches. Adult amphipods were collected at eight localities on the Tuscany shore in summer. Concentrations of 16 PAHs indicated as priority pollutants by the Environmental Protection Agency were determined.
View Article and Find Full Text PDFTo return to the ecologically optimal zone of the beach, the sandhopper Talitrus saltator (Montagu) maintains a constant sea-land direction based on the sun and moon compasses. In this study, we investigated the role of the skylight gradient of luminance in sun and moon identification under natural and artificial conditions of illumination. Clock-shifted (inverted) sandhoppers tested under the sun (during their subjective night) and under the full moon (during their subjective day) exhibit orientation in accordance with correct identification of the sun and the moon at night.
View Article and Find Full Text PDFWe investigated behavioural responses (locomotor activity and substrate selection) of the amphipod Talitrus saltator after laboratory exposure to different concentrations of Hg, Cu and Cd. Locomotor activity, measured with a microwave radar device, was assessed in animals exposed to contaminated sand and in sandhoppers previously kept for 48 h in contaminated seawater and tested in clean sand. The contents of Hg, Cu and Cd in T.
View Article and Find Full Text PDFThe role of salinity in the ecophysiology of many intertidal invertebrates has been extensively investigated. Calcium (Ca(2+)), magnesium (Mg(2+)), potassium (K(+)) and sodium (Na(+)) are the major constituents of seawater and it has been demonstrated that sandhoppers tested under the sun in diluted seawater (3.5 per thousand) head seaward, instead of going landward as expected.
View Article and Find Full Text PDFAlthough many studies have focused on trace metals accumulation, investigations of talitrid amphipods as biomarkers are rare. This study explores the possibility of using the solar orientation capacity of Talitrus saltator as a behavioural marker of exposure to two essential (Cu and Zn) and two non-essential (Cd and Hg) metals. LC(50) analyses performed before the solar orientation tests showed that the 72 h LC(50) for Hg was 0.
View Article and Find Full Text PDFThe present paper assesses the use of the supralittoral amphipod Talitrus saltator as a bioindicator of the effects of human trampling on the supralittoral sandy band. Samplings in delimited areas were carried out at sites subjected to different human impact. The results showed a strong negative correlation between the number of swimmers and the sandhopper population density, while there was no clear relationship between sandhopper abundance and the other factors considered: granulometry, compactness and organic carbon content of the sand, and trace metal contents in the sand and sandhoppers.
View Article and Find Full Text PDFJ Comp Physiol A Neuroethol Sens Neural Behav Physiol
December 2007
The sandhopper Talitrus saltator has an endogenous activity rhythm with a circadian periodicity. It is well known for its ability to compensate for the apparent movement of the sun during its migrations along the sea-land axis of the beach. Both chronometric mechanisms are entrained by the natural LD photoperiod.
View Article and Find Full Text PDFThe use of the landscape in the zonal recovery of Talitrus saltator (Montagu) was demonstrated in the past using natural and artificial landscapes. Here we evaluate the importance of colour in the landscape orientation of sandhoppers. Adult individuals of T.
View Article and Find Full Text PDFOur experiments, carried out at night and during the day on adults and laboratory-born young of the sandhopper Talitrus saltator, deal with the identification and use of the moon as an orientating factor. Sandhoppers were released in an apparatus (a Plexiglas dome) that produced a scenario similar to the natural one (with artificial sky, moon or sun illuminated at different intensities). When tested at night, the adult and young sandhoppers used the artificial moon like the natural one, independently of the intensity of illumination of the artificial sky and moon.
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