scholarly journals Possible influence of salmon farming on long-term resident behaviour of wild saithe (Pollachius virens L.)

2014 ◽  
Vol 71 (9) ◽  
pp. 2484-2493 ◽  
Author(s):  
Håkon Otterå ◽  
Ove T. Skilbrei
Keyword(s):  
Large Scale ◽  
Migration Routes ◽  
Salmon Farming ◽  
Dynamic Relationship ◽  
Natural Behaviour ◽  
Scale Population ◽  
Acoustic Tags ◽  
Release Area ◽  
And Migration

Abstract The culture of Atlantic salmon is one of the most developed aquaculture industries in the world. The production from smolt to market size usually takes place in sea cages in open waters, and these structures tend to attract wild fish, as they do for other farmed species. For salmon farming, saithe (Pollachius virens) is one of the most-frequently observed species around sea cages. An important question is whether the large concentration of salmon farms in some areas might alter the natural behaviour and migration pattern of wild saithe. We tagged 62 wild saithe with acoustic tags and followed their movements for up to 2 years in an area in Southwestern Norway with many salmon farms. Furthermore, nearly 2000 saithe were tagged with external T-bar tags to study migration beyond the study area. The recaptures of the T-bar tagged saithe from offshore areas suggest that the offshore migration routes of saithe are similar to published results from before salmon farming became significant in the area. However, a large proportion of the saithe population appears to remain in the release area and was observed at the salmon farms for much of the time. We conclude that the aquaculture industry is influencing the local saithe distribution. Large-scale population effects are more difficult to prove, but it is possible that the dynamic relationship between the coastal and oceanic phases has been altered.

Automated monitoring of a large-scale cod (Gadus morhua) migration in the open sea

2002 ◽  
Vol 59 (12) ◽  
pp. 1845-1850 ◽  
Author(s):  
Luc A Comeau ◽  
Steven E Campana ◽  
Martin Castonguay
Keyword(s):  
Large Scale ◽  
Gadus Morhua ◽  
Atlantic Cod ◽  
Seasonal Migration ◽  
Migration Routes ◽  
Eastern Canada ◽  
Migration Patterns ◽  
Migration Timing ◽  
Open Sea ◽  
And Migration

The migration patterns of marine fishes are poorly known, in part owing to the technical limitations associated with tracking the movements of animals in deep water. Here we document a large-scale, directed, migration of Atlantic cod (Gadus morhua) off eastern Canada. Our approach was based on the acoustic tagging of 126 fish and the deployment of 69 subsurface receivers, stretching over a 160-km distance along the edge of the Laurentian Channel. After 1 year of automated recording, we found that 65% of the fish migrated out of coastal waters in two distinct runs during the summer–autumn period. The offshore-migrating fish overwintered in deep Laurentian Channel waters, returning inshore in April. Individual migration routes and migration timing were variable, indicating that the cod did not aggregate in large schools during the seasonal migration events.

scholarly journals Securitization and Community-Based Protection Among Chin Refugees in Kuala Lumpur

2018 ◽  
Vol 28 (2) ◽  
pp. 158-178 ◽  
Author(s):  
Kirsten McConnachie
Keyword(s):  
Identity Construction ◽  
Forced Migration ◽  
Community Organizations ◽  
Kuala Lumpur ◽  
Long Term Effects ◽  
Community Based ◽  
Dynamic Relationship ◽  
Local Protection ◽  
And Migration

This article examines refugee-led community organizations among Chin refugees from Myanmar in Kuala Lumpur. It uses a structuration analysis that recognizes refugee-led organizations as complex governance entities engaged in a dynamic relationship with (among others) national policies of securitization of forced migration and international humanitarian governance. This approach expands the existing literature on the securitization of forced migration by exploring refugees’ lived experiences in a context of south–south migration. It expands the literature on community-based protection by going beyond recognizing the existence of refugee-led organizations to analyse their construction, constitution and consequences. Three primary areas of work by Chin refugee groups are analysed in relation to their immediate activity and longer term effects: organization (‘building ethnic unity in adversity’), documentation (‘asserting a bureaucratic identity’) and socialization (‘learning to be illegal’). These long-term effects indicate the possible impact of local protection activities on macrostructural processes such as identity construction and migration choices.

Hybrid Information Systems for Agriculture: The Case of Cattle Trypanosomiasis in Africa

1994 ◽  
Vol 23 (4) ◽  
pp. 261-267 ◽  
Author(s):  
Iain J. Mckendrick ◽  
George Gettinby ◽  
Yiqun Gu ◽  
Andrew Peregrine ◽  
Crawford Revie
Keyword(s):  
Information Technology ◽  
Hybrid System ◽  
Food Production ◽  
Large Scale ◽  
Sub Saharan Africa ◽  
Software Systems ◽  
High Quality ◽  
Scale Population ◽  
Sub Saharan

Large scale population growth in sub-Saharan Africa makes it imperative to achieve an equivalent increase in food production in this area. It is also important that any increase be sustainable in the long-term, not causing lasting damage to local ecosystems. Recent advances in information technology make the successful diffusion of relevant expertise to farmers a more practical option than ever before. How this might be achieved is described in this paper, which considers the transfer of expertise in the diagnosis, treatment and management of trypanosomiasis in cattle. Using current technology, the combination of different software systems in one integrated hybrid system could allow the delivery of high quality, well focused information to the potential user.

scholarly journals Conflicting Perspectives on the “Migrant Crisis” in the Horn of Africa

2018 ◽  
pp. 228-244 ◽  
Author(s):  
John R. Campbell
Keyword(s):  
Large Scale ◽  
Action Plan ◽  
The European Union ◽  
Horn Of Africa ◽  
Apparent Paradox ◽  
Population Displacement ◽  
Nation States ◽  
And Migration

In sharp contrast to the sense of a “migrant crisis” which prevails in Europe, nation states in the Horn of Africa understand migration, including state-induced population displacement, as unexceptional. The chapter addresses this apparent paradox by contrasting European policy discourse on migration with the long-term political and structural processes in northeastern Africa that cause population displacement and migration. The chapter then examines the migration policies of governments in the Horn and concludes by arguing that the European Union misrepresents and misunderstands the factors responsible for large-scale migration and the role of states in exploiting migrants. For these reasons it is highly unlikely that the EU-Horn of Africa Action Plan/Khartoum process will bring about better border management policies and practices.

Long-term incidence of secondary bladder and rectal cancer in patients treated with brachytherapy for localized prostate cancer: a large-scale population-based analysis

2019 ◽  
Vol 124 (6) ◽  
pp. 1006-1013 ◽  
Author(s):  
Elio Mazzone ◽  
Francesco A. Mistretta ◽  
Sophie Knipper ◽  
Carlotta Palumbo ◽  
Zhe Tian ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Rectal Cancer ◽  
Large Scale ◽  
Population Based ◽  
Localized Prostate Cancer ◽  
Scale Population

scholarly journals Reliability of the NIH toolbox cognitive battery in children and adolescents: a 3-year longitudinal examination

2020 ◽  
pp. 1-10
Author(s):  
Brittany K. Taylor ◽  
Michaela R. Frenzel ◽  
Jacob A. Eastman ◽  
Alex I. Wiesman ◽  
Yu-Ping Wang ◽  
...  
Keyword(s):  
Large Scale ◽  
Intraclass Correlation ◽  
Temporal Stability ◽  
Correlation Coefficients ◽  
Population Level ◽  
Clinical Applications ◽  
Intraclass Correlation Coefficients ◽  
Scale Population ◽  
Longitudinal Examination

Abstract Background The Cognitive Battery of the National Institutes of Health Toolbox (NIH-TB) is a collection of assessments that have been adapted and normed for administration across the lifespan and is increasingly used in large-scale population-level research. However, despite increasing adoption in longitudinal investigations of neurocognitive development, and growing recommendations that the Toolbox be used in clinical applications, little is known about the long-term temporal stability of the NIH-TB, particularly in youth. Methods The present study examined the long-term temporal reliability of the NIH-TB in a large cohort of youth (9–15 years-old) recruited across two data collection sites. Participants were invited to complete testing annually for 3 years. Results Reliability was generally low-to-moderate, with intraclass correlation coefficients ranging between 0.31 and 0.76 for the full sample. There were multiple significant differences between sites, with one site generally exhibiting stronger temporal stability than the other. Conclusions Reliability of the NIH-TB Cognitive Battery was lower than expected given early work examining shorter test-retest intervals. Moreover, there were very few instances of tests meeting stability requirements for use in research; none of the tests exhibited adequate reliability for use in clinical applications. Reliability is paramount to establishing the validity of the tool, thus the constructs assessed by the NIH-TB may vary over time in youth. We recommend further refinement of the NIH-TB Cognitive Battery and its norming procedures for children before further adoption as a neuropsychological assessment. We also urge researchers who have already employed the NIH-TB in their studies to interpret their results with caution.

scholarly journals Participant Recruitment Challenges in Researching Peer Groups and Migration Retrospectively

2017 ◽  
Vol 13 (4) ◽  
pp. 48-69
Author(s):  
Paula Pustułka ◽  
Natalia Juchniewicz ◽  
Izabela Grabowska
Keyword(s):  
Longitudinal Study ◽  
Large Scale ◽  
Peer Group ◽  
Peer Groups ◽  
Participant Recruitment ◽  
Know How ◽  
Recruitment Challenges ◽  
Group Members ◽  
And Migration

This paper discusses the challenges of researching peer groups through a multi-focal, temporal lens in a retrospective manner. Embedded in a broader “Peer Groups & Migration” Qualitative Longitudinal Study (QLS), the article focuses on recruiting young respondents (aged 19-34 at present) who originally come from one of the three medium-sized towns in Polish localities and are either migrants or stayers connected to mobile individuals. The respondents are tracked retrospectively and asked to discuss their adolescence, as well encouraged to provide contacts to their youth Peer Group members. Based on fieldwork experiences and field access challenges, four models of recruiting migrants’ high school peer groups are presented. Furthermore, variants and rationales of non-recruitment are also provided. Focusing on the process of establishing a long-term and large-scale peer panel in the QLS, the paper contributes detailed know-how and strategies around participant recruitment.

scholarly journals Using Food Webs and Metabolic Theory to Monitor, Model, and Manage Atlantic Salmon—A Keystone Species Under Threat

2021 ◽  
Vol 9 ◽  
Author(s):  
Guy Woodward ◽  
Olivia Morris ◽  
José Barquín ◽  
Andrea Belgrano ◽  
Colin Bull ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Large Scale ◽  
Keystone Species ◽  
Population Data ◽  
Metabolic Theory ◽  
Huge Data ◽  
Scale Population ◽  
Natural Range ◽  
Underlying Causes

Populations of Atlantic salmon are crashing across most of its natural range: understanding the underlying causes and predicting these collapses in time to intervene effectively are urgent ecological and socioeconomic priorities. Current management techniques rely on phenomenological analyses of demographic population time-series and thus lack a mechanistic understanding of how and why populations may be declining. New multidisciplinary approaches are thus needed to capitalize on the long-term, large-scale population data that are currently scattered across various repositories in multiple countries, as well as marshaling additional data to understand the constraints on the life cycle and how salmon operate within the wider food web. Here, we explore how we might combine data and theory to develop the mechanistic models that we need to predict and manage responses to future change. Although we focus on Atlantic salmon—given the huge data resources that already exist for this species—the general principles developed here could be applied and extended to many other species and ecosystems.

scholarly journals Shifting of the Migration Route of White-Naped Crane (Antigone vipio) Due to Wetland Loss in China

2021 ◽  
Vol 13 (15) ◽  
pp. 2984
Author(s):  
Yifei Jia ◽  
Yunzhu Liu ◽  
Shengwu Jiao ◽  
Jia Guo ◽  
Cai Lu ◽  
...  
Keyword(s):  
Large Scale ◽  
Migratory Birds ◽  
Wetland Loss ◽  
Migration Route ◽  
Bohai Bay ◽  
Migration Routes ◽  
Utilization Distribution ◽  
Stopover Site ◽  
Conservation Actions

In the last 15 years, the west population of white-naped crane (Antigone vipio) decreased dramatically despite the enhanced conservation actions in both breeding and wintering areas. Recent studies highlighted the importance of protecting the integrity of movement connectivity for migratory birds. Widespread and rapid landcover changes may exceed the adaptive capacity of migrants, leading to the collapse of migratory networks. In this study, using satellite tracking data, we modeled and characterized the migration routes of the white-naped crane at three spatial levels (core area, migratory corridor, and migratory path) based on the utilization distribution for two eras (1990s and 2010s) spanning 20 years. Our analysis demonstrated that the white-naped crane shifted its migratory route, which is supported by other lines of evidences. The widespread loss of wetlands, especially within the stopover sites, might have caused this behavioral adaptation. Moreover, our analysis indicated that the long-term sustainability of the new route is untested and likely to be questionable. Therefore, directing conservation effects to the new route might be insufficient for the long-term wellbeing of this threatened crane and large-scale wetland restorations in Bohai Bay, a critical stopover site in the East Asian-Australasian flyway, are of the utmost importance to the conservation of this species.

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