Search results for "Acu"

Surgical implantation of electronic tags does not induce medium-term effect: insights from growth and stress physiological profile in two marine fish…

2020

Abstract Background Telemetry applied to aquatic organisms has recently developed greatly. Physiological sensors have been increasingly used as tools for fish welfare monitoring. However, for the technology to be used as a reliable welfare indicator, it is important that the tagging procedure does not disrupt fish physiology, behaviour and performance. In this communication, we share our medium-term data on stress physiological profile and growth performance after surgical tag implantation in two important marine fish species for European aquaculture, the sea bream (Sparus aurata) and the European sea bass (Dicentrarchus labrax). Results Blood samples after surgical tag implantation (46 day…

Incidental catch of loggerhead sea turtles (Caretta caretta) along the Sicilian coasts by longline fishery

2018

It has been estimated that 44,000 Caretta caretta turtles die every year due to anthropomorphic activity in the Mediterranean Sea, and that longline fishing is one of the most significant causes of mortality. A total of 482 specimens of C. caretta were rescued from different parts of the Sicilian coast (Mediterranean Sea) from 2014 to 2016. The most numerous stranding was recorded during the spring and summer seasons, mainly along the north and eastern coasts of Sicily. The curved carapace length for all the specimens ranged from between 19 and 95 cm and most of these were young or sub adults. The highest number of strandings was recorded in 2014 and 2015, with 206 and 169 individuals, resp…

Introduced alien signal crayfish (Pacifastacus leniusculus) in Finland : uncontrollable expansion despite numerous crayfisheries strategies

2018

In Finland, massive signal crayfish introductions started towards the end of 1980s, with an estimated total of 2.2 million signal crayfish been stocked before year 2016. During that period, Finnish fisheries authorities have implemented three national management strategies setting guidelines for the crayfish introductions. The main aims of the strategies have been conservation of native noble crayfish stocks and a controlled spreading of the alien signal crayfish within a designated region. In this study, we report the current distribution of signal crayfish in Finland in comparison to the guidelines set in these three national strategies. The present distribution area of the signal crayfis…

Population structure, life cycle, and trophic niche of the glacial relict amphipod, Gammaracanthus lacustris , in a large boreal lake

2019

Sex- and size-selective harvesting of corkwing wrasse (Symphodus melops)—a cleaner fish used in salmonid aquaculture

2016

Fishery-induced changes in sex ratios can have negative effects on reproductive rates and affect sexual selection and evolutionary trajectories. Here, we investigate sex- and size-selectivity of the fishery for corkwing wrasse (Symphodus melops) in Western Norway. The males that build and guard nests (nesting males) grow faster than females and sneaker males. Corkwing wrasse were tagged (n = 1057) during (May–June) and after (July) the spawning period in 2014 within a no-take site and in a nearby site open for fishing. We monitored the fishery within and nearby the tagging sites from June to October and sampled recaptures on all commercial fishing trips. Fishing mortality was higher for nes…

2021

Without insights into the threats affecting species across their distributions and throughout their annual cycles, effective conservation management cannot be applied. The Whenua Hou diving petrel Pelecanoides whenuahouensis (WHDP) is a Critically Endangered small seabird whose offshore habits and threats are poorly understood. We tracked WHDPs year-round in 2015/16, 2017/18, and 2018/19 using global location-sensing immersion loggers to identify offshore distribution, movements, behaviour, and overlap with commercial fishing effort. During the breeding period, WHDPs ranged from southern Aotearoa (New Zealand) to Maukahuka (Auckland Islands). After breeding, WHDPs migrated southwest towards…

Control of off-flavor compounds in a full-scale recirculating aquaculture system rearing rainbow trout Oncorhynchus mykiss

2020

Fish is increasingly produced in recirculating aquaculture systems (RAS), which can offer some production and environmental benefits. Unfortunately, there is a tendency to develop off-flavors in RA...

Characteristics of Acute Toxicity Dynamics of Selected Toxicants on Aquatic Crustaceans

2019

Abstract Determining the value of a half-effective or half-life concentration or dose of toxicant is the main purpose of acute toxicity studies, and this is also the most commonly used value in the toxicity characteristics of substances. By conducting tests that meet the criteria and requirements for the determination of acute toxicity, due to the use of appropriate mathematical tools and concentrations resulting in complete lethal effects in the studied groups, considerably more important values can be achieved, which give a possibility for the analysis of the entire process’s dynamics, as well as determining the threshold values of the effect time and toxicant concentration. This was the …

Dynamic Energy Budget provides mechanistic derived quantities to implement the ecosystem based management approach

2019

Abstract The on-going climate change threats are rapidly growing at both global and local scales, affecting ecosystems, societies and economies by altering natural distribution and productivity of key commercial species. Although the ecosystem based management (EBM) focuses on ecosystem equilibria, to provide realistic management measures for important activities at sea such as fisheries and aquaculture, there is a need of quantities; mechanistic approaches are suggested as reliable solutions. Here, a Dynamic Energetic Budget (DEB) application studies the link between environmental change (temperature forecasted increasing scenario in a context of COP 21 [Paris climate conference Agreement]…

Nest Insulation in the European Robin (Erithacus Rubecula): Effects of Latitude and Construction Materials

2016

The various roles that birds’ nests play are widely discussed and there is increasing interest in developing a better understanding of how they achieve these roles. The insulatory properties of nests have been investigated in a variety of songbird species and can vary with temperature and latitude. However, data are only available for a limited number of species. Here, we study the variations of the insulatory properties of European Robin ( Erithacus rubecula) nests in conjunction with the morphology of the nests and composition of the materials used in construction. As well as quantifying the materials used to construct these nests for the first time, we test the hypothesis that there is …