Search results for " Fishery"
showing 10 items of 43 documents
Ocean-scale connectivity and life cycle reconstruction in a deep-sea fish
2014
Author's version of an article in the journal: Canadian Journal of Fisheries and Aquatic Sciences. Also available from the publisher at: http://dx.doi.org/10.1139/cjfas-2013-0343 As human exploration and harvesting moves to the high seas, ecological understanding of the deep sea has become a priority, especially in those commercially exploited species whose life cycle, habitat use, and demographic structure remain poorly understood. Here we combine otolith trace element and stable isotope analyses with microsatellite data to investigate population structure and connectivity in the migratory deep-sea black scabbardfish (Aphanopus carbo), sampled along a latitudinal gradient spanning much of …
Socializing makes thick-skinned individuals: on the density of epidermal alarm substance cells in cyprinid fish, the crucian carp (Carassius carassiu…
2010
Published version of an article in the journal: Journal of Comparative Physiology A: Neuroethology, Sensory, Neural, and Behavioral Physiology. Also available on SpringerLink: http://dx.doi.org/10.1007/s00359-010-0550-4 In cyprinid fish, density of epidermal club cells (i.e. alarm substance cells) has been found to vary between lakes with different predator fauna. Because predators can be labelled with chemical cues from prey, we questioned if club cell density could be controlled indirectly by predators releasing prey cues. In particular, we suspected a possible feedback mechanism between chemical alarm signals and their cellular source. We raised crucian carp singly and in groups of four.…
A Note on Economic Impact of EFF on Sicilian Firms Performance
2018
Measure 2.3 of the European Fisheries Fund, in Sicily, claimed investments of fish firms in production capacity expansion and modernization of fish processing. Have these investments been effective in supporting the competitiveness of these firms and have they influenced the economic sustainability of the regional seafood chain? Proposed counterfactual analysis contributes to this assessment through a comparison of the business performance of funded and non-funded firms.
Challenging fear: chemical alarm signals are not causing morphology changes in crucian carp (Carassius carassius)
2010
Published version of an article in the journal: Environmental Biology of Fishes. Also available at SpringerLink: http://dx.doi.org/10.1007/s10641-010-9707-9 Crucian carp develops a deep body in the presence of chemical cues from predators, which makes the fish less vulnerable to gape-limited predators. The active components originate in conspecifics eaten by predators, and are found in the filtrate of homogenised conspecific skin. Chemical alarm signals, causing fright reactions, have been the suspected inducers of such morphological changes. We improved the extraction procedure of alarm signals by collecting the supernatant after centrifugation of skin homogenates. This removes the minute …
Deep-sea shrimp fishery in Sicily: The economic performance of the shrimp trawling fleet in the ports of Mazara del Vallo, Sciacca, and Porto Empedoc…
2006
Shrimp fishing in Sicily is carried out by fishing companies using trawlers and multifunctional vessels equipped with trawling nets, in a complex and worrisome context, because of the decrease in catch over the last few years. After analysing the structural characteristics of Sicilian trawling, the study concentrates on the three most important shrimp fishing ports in Sicily: Mazara del Vallo, Sciacca, and Porto Empedocle. For each fleet, through a sample analysis, economic performance has been evaluated for the period from 2001 to 2003. Finally, a comparative analysis of the economic performance of the surveyed companies is carried out through a comparison of daily economic productivity in…
The Developmental Contribution From Mobile Phones Across the Agricultural Value Chain in Rural Africa
2011
Published version of an article from the journal: The Electronic Journal of Information Systems in Developing Countries. Also available fro the publisher: http://www.ejisdc.org/Ojs2/index.php/ejisdc/article/viewFile/849/377 The most widespread information and communication technology (ICT) in developing countries today is the mobile phone. The majority of people in the least developed countries still live in rural areas and their livelihood depends on the primary industries. This study investigates the use of mobile phones among farmers in rural Tanzania in order to supply empirical data on the developmental role of this technology. The results show that the improved access to communication…
Spatially structured interactions between lobsters and lobster fishers in a coastal habitat: fine-scale behaviour and survival estimated from acousti…
2013
Fishing can have profound impacts on the ecology and evolution of marine populations. Understanding population-level changes ultimately depends on knowledge about individual survival and how it varies in time and space. We used acoustic tags and a network of receivers to monitor individual behaviour and fate of European lobster (Homarus gammarus) exposed to commercial and recreational trap fisheries on the Norwegian Skagerrak coast. In August 2011, 50 male lobsters above minimum legal size were tagged and monitored before and during the lobster fishing season. We also quantified the spatial and temporal variation in fishing activity. There was no significant effect of home-range size on th…
Catch-and-release of Atlantic cod (Gadus morhua): post-release behaviour of acoustically pretagged fish in a natural marine environment
2014
Studying the sublethal effects of catch-and-release (C&R) is challenging, as there are several potential sources of bias. For example, if behavioural alterations immediately after the release event are to be studied, separation of tagging effects from actual C&R effects is required, which is a challenge in the wild, particularly in marine environments. To investigate the effects of C&R on Atlantic cod (Gadus morhua) in their natural environment, 80 cod were caught in fyke nets, fitted with acoustic transmitters, and released. After recovery from tagging and handling for at least 14 days, nine individuals were recaptured and released at least once during experimental angling, fo…
Wind forcing and fate of <i>Sardinella aurita</i> eggs and larvae in the Sicily Channel (Mediterranean Sea)
2015
Abstract. Multidisciplinary studies are recently seeking to define diagnostic tools for fishery sustainability by coupling ichthyoplanktonic datasets, physical and bio-geochemical oceanographic measurements, and ocean modelling. The main goal of these efforts is the understanding of those processes that control fate and dispersion of fish larvae and eggs and thus tune the inter-annual variability of biomass of fish species. We here analyzed eggs and larvae distribution and biological features of Sardinella aurita in the northeast sector of the Sicily Channel (Mediterranean Sea) collected during the 2010 and 2011 summer cruises. We make use of satellite sea surface temperature, wind, and chl…
Climate change and genetic structure of leading edge and rear end populations in a northwards shifting marine fish species, the corkwing wrasse (Symp…
2013
Published version of an article in the journal:PLoS ONE. Also available from the Public Library of Science: http://dx.doi.org/10.1371/journal.pone.0067492 Open Access One mechanism by which marine organisms may respond to climate shifts is range shifts. The corkwing wrasse (Symphodus melops) is a temperate fish species, inhabiting the coasts of Europe, that show strong indications of current as well as historical (ice-age) range shifts towards the north. Nine neutral microsatellite DNA markers were screened to study genetic signatures and spatial population structure over the entire geographic and thermal gradient of the species from Portugal to Norway. A major genetic break (FST = 0.159 a…