Fish abundance in the Wilderness and Swartvlei lake systems: changes relative to environmental factors

1996 ◽  
Vol 31 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Ian A. Russell
2017 ◽  
Vol 13 (2) ◽  
pp. 63
Author(s):  
Wijopriono Wijopriono

The relationship between the variations in density of pelagic fish in the Java Sea and a suite of variables describing the environment was studied. The indicator of density (local fish abundance) used were catch per unit of effort, obtained from 1,198 catches made by commercial fishing during the 5 year period (1998 until 2002), and number of fish per unit of area from acoustic investigation made in 2002.


Diversity ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 219
Author(s):  
Margaret Mercer ◽  
Peter C. Searle ◽  
Roberto Cifuentes ◽  
Evelyn Habit ◽  
Mark C. Belk

Body and head shape in fish responds to environmental factors such as water flow rate, food sources, and niche availability. However, the way in which fish respond to these environmental factors varies. In Central Chile, multiple river and lake systems along the coast provide an ideal study site to investigate these types of shape changes. We use geometric morphometrics to characterize shape differences in Galaxias maculatus (Jenyns) between river and lake populations. Lake fish converge on a shape with a more fusiform body, narrower head, and larger eyes, while river fish have a more robust body, rounder head, and smaller eyes. These shape changes are consistent with a shift to zooplanktivorous foraging in lakes, as evidenced in other systems. Unlike some fish species that develop polymorphisms in body shape after colonization (e.g., benthic and limnetic forms), G. maculatus in lakes exhibit a monomorphic limnetic form.


Hydrobiologia ◽  
2021 ◽  
Author(s):  
S. Matern ◽  
T. Klefoth ◽  
C. Wolter ◽  
R. Arlinghaus

AbstractThe type and extent of habitats along the shoreline specify the distribution of fish in the littoral zone of lakes, but effects are likely species and size-specific and might be overwhelmed by lake-level environmental factors that drive fish abundance (e.g. trophic state). We applied a replicated transect-sampling design by electrofishing assessing fish abundance and distribution along the banks of 20 gravel pit lakes in Lower Saxony (Germany). Boosted regression trees were used to analyse the impact of different characteristic habitat types (e.g. vegetated, woody or open water zones), shoreline water depth and lake-level environmental variables on species-specific fish abundances. In contrast to earlier studies, lake-level environment and transect-level habitat type similarly influenced the abundances of differently sized fish species in the littoral zone of gravel pit lakes. The abundance of almost all fish species increased with lake productivity and extent of structured littoral habitats, mostly following non-linear relationships. Our work suggests that investments into the quality of littoral habitat, and not merely the control of nutrient inputs or other lake-level environmental factors, can promote abundance of most gravel pit lake fish species, in particular those who depend on the littoral zone for at least part of their life-cycle.


2019 ◽  
Vol 42 ◽  
Author(s):  
Nicole M. Baran

AbstractReductionist thinking in neuroscience is manifest in the widespread use of animal models of neuropsychiatric disorders. Broader investigations of diverse behaviors in non-model organisms and longer-term study of the mechanisms of plasticity will yield fundamental insights into the neurobiological, developmental, genetic, and environmental factors contributing to the “massively multifactorial system networks” which go awry in mental disorders.


2020 ◽  
Vol 134 (18) ◽  
pp. 2447-2451
Author(s):  
Anissa Viveiros ◽  
Gavin Y. Oudit

Abstract The global prevalence of obesity has been rising at an alarming rate, accompanied by an increase in both childhood and maternal obesity. The concept of metabolic programming is highly topical, and in this context, describes a predisposition of offspring of obese mothers to the development of obesity independent of environmental factors. Research published in this issue of Clinical Science conducted by Litzenburger and colleagues (Clin. Sci. (Lond.) (2020) 134, 921–939) have identified sex-dependent differences in metabolic programming and identify putative signaling pathways involved in the differential phenotype of adipose tissue between males and females. Delineating the distinction between metabolically healthy and unhealthy obesity is a topic of emerging interest, and the precise nature of adipocytes are key to pathogenesis, independent of adipose tissue volume.


2016 ◽  
Vol 1 (12) ◽  
pp. 83-93 ◽  
Author(s):  
Mary Blake Huer ◽  
Travis T. Threats

The World Health Organization's (WHO's) 2001 International Classification of Functioning Disability and Health (ICF) has as one of its central tenets the full inclusion of persons with disabilities in society. It acknowledges the need for medical and rehabilitation intervention in its biopscychosocial framework. However, the WHO realizes that society must do its part to facilitate this full participation and empowerment. Persons with complex communication needs (PWCCN) often need augmentative and alternative communication (AAC) in order to express themselves. However, in order to access and successfully use AAC, PWCCN need access to the necessary AAC devices and services, as well as a willing society to interact with them as full contributing members of society. The factors outside of a person's specific physical and/or cognitive functional limitations are addressed in the ICF via the Personal and Environmental Factors. Personal Factors include the individual's personality traits, lifestyle, experiences, social/educational/professional background, race, gender, and age. Environmental Factors include community support systems, social service agencies, governments, social networks, and those persons that interact with the PWCCN. This article addresses the sociopolitical influences on PWCCN and their functioning from a human rights perspective. The necessary introspective role of speech-language pathologists in this process is explored.


2004 ◽  
Vol 171 (4S) ◽  
pp. 99-99
Author(s):  
Vincenzo Serretta ◽  
Vincenzo Altieri ◽  
Giuseppe Morgia ◽  
Rosalinda Allegro ◽  
Alessandra Di Lallo ◽  
...  

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