Search results for "CLASSIFICATION"
showing 10 items of 29475 documents
Traditional and experimental floating fish aggregating devices in the Gulf of Castellammare (NW Sicily): Results from catches and visual observations
1999
Floating fish aggregating devices (FADs) have long been used to attract fish in NW Sicily since antiquity. Recently, a number of changes have been made to the type of material employed to construct FADs, with the aim of increasing their effectiveness. In this paper we compare the catches made at eight experimental floating FADs (polypropylene ropes frayed at the ends) with those obtained at eight traditional FADs in the Gulf of Castellammare. A total of 672 samples were collected during summer and autumn in 1995 and 1996 at the 16 FADs using a surrounding net. Visual observations of fishes associated with the FADs were also conducted to obtain qualitative information about the spatial distr…
Distribution and biology of the Blackmouth catshark Galeus melastomus in the Strait of Sicily (Central Mediterranean Sea)
2009
The Blackmouth catshark, Galeus melastomus, Rafinesque, 1810 (Carcharhiniformes; Scyliorhinidae), is a common, although at present discarded, by- catch of the bottom trawl fisheries in the Strait of Sicily. Given its ecological interest, data gathered in experimental bottom trawl surveys were analysed in order to describe its distribution and main biological traits. The Blackmouth catshark was sampled almost exclusively on the upper slope (200-800), showing the highest frequency of occurrence (69-100%), biomass (BI; 10-85 kg*km-2) and density (DI; 54-506 N*km-2) indexes in the deeper (501-800m) grounds. Individual size (total length, TL, mm) were between 70-590 and 90-510 in females and mal…
First report of an olive ridley (Lepidochelys olivacea) inside the Mediterranean Sea
2015
We report the first confirmed occurrence of a Lepidochelys olivacea in the Mediterranean Sea based on the study of an individual stranded on a beach, located in the town of Oropesa del Mar (40º05ʹ32ʺN, 0º08ʹ02ʺE), Castellón province, East Spain, in May 2014. Morphological and genetic analyses were used to confirm the identification of the species. The individual had a sequence that matched the 470 bp Lepidochelys olivacea haplotype F (Genbank accession number: AF051773), found in several Atlantic populations. This becomes one of the northernmost known occurrences of olive ridleys in the world and is the first reports of this species in the Mediterranean Sea.
New Mediterranean Marine biodiversity records (December, 2013)
2013
M. Bilecenoglu [et al.]
The role of two non-indigenous serpulid tube worms in shaping artificial hard substrata communities: case study of a fish farm in the central Mediter…
2019
Understanding the spread and establishment of non-indigenous species (NIS) is one of the primary areas of focus in bioinvasion science and is essential for generating appropriate management strategies in aquaculture. Here we investigated the role of 2 non-indigenous serpulid tube worms (Hydroides elegans and H. dirampha) in shaping the hard substrata communities around a fish farm in the Strait of Sicily over 1 yr (June 2014-June 2015), at 3 mo intervals (September and December 2014, March and June 2015). The mean density values of serpulids were significantly different at each sampling time. The density of serpulids on submerged panels showed a peak in spring (March 2015, after 9 mo) and d…
Spectrofluorimetric study of dissolved organic matter in River Salaca (Latvia) basin waters
2012
Dissolved organic matter (DOM) in surface waters influences mineral weathering, nutrient cycling, aggregation of particulate matter and photochemical reactions in waters and aquatic communities. In this study, the effectiveness of UV and fluorescence measurements in distinguishing the origin of DOM and processes within the river basin were analyzed using the River Salaca basin as an example. The basin of River Salaca is characterized by low anthropogenic pressure, however, the water color during the last few decades has increased (an effect known as brownification). As tools to study the composition of dissolved organic substances in waters of the River Salaca and its tributaries the use of…
Invasive crayfish increase habitat connectivity: a case study in a large boreal lake
2013
Several studies have shown that distinct compartments of lake ecosystems are coupled via transportation of organic matter, nutrients and energy across habitat boundaries. Here we evaluate the potential of the invasive signal crayfish (Pacifastacus leniusculus (Dana)) to modify energy pathways in large boreal lakes. Using a stable isotope mixing model and calculation of the isotopic niches we estimated the contribution of different food sources to the diets of crayfish captured from different habitats, and from that inferred their potential to transport energy across the littoral-profundal gradient. The crayfish caught from the littoral area utilized mainly littoral food sources, whereas the…
Reproductive features of the deep-water rose shrimp, Parapenaeus longirostris (Crustacea: Penaeidae), in the Strait of Sicily
2010
The deep‑water rose shrimp, Parapenaeus longirostris (Lucas, 1846), is one of the most valuable and heavily exploited demersal species of the Mediterranean bottom trawl fisheries. The basic life traits of this shrimp, in particular its reproductive aspects, are regularly monitored during experimental trawl surveys carried out in the Mediterranean Sea. Gonadic condition and maturity status for estimating the size at onset of sexual maturity are commonly assessed in females, using macroscopic color scales, histologically validated only in a few geographical areas. In this study, histological analyses were performed on rose shrimps collected from a trawl survey carried out in the Strait of Sic…
Why do female and male taekwondo athletes win the bout? An analysis based on the Olympic weight category and the result of the bout
2020
Combat sports such as taekwondo, where athletes compete against an opponent require control of technique and tactics, as well as knowing the optimal performance of opponents to win the bout. Therefore, the aim of the present study was to analyse the Olympic competitors (London Olympic Games), according to the weight category (fly, feather, light and heavy) and according to the performance in their fighting (winner vs. loser) in each gender. An observational methodology was used, following a nomothetic, follow-up and multidimensional design of 302 individual performances. The statistical analysis used an ANOVA and T Student test for comparing frequencies. The results obtained indicate signif…
A Study of Mechanical Properties of Polymer Composite Membranes with Various Ionic Liquids at Elevated Temperatures
2019
This work was supported by Latvian Council of Science (Cooperation project No.666/2014.4).