Empirical Estimation of Accumulation-Induced Change in Gill Net Catch-ability : Mind the Observation Errors
Marjomäki, T., Paloniemi, M., Keskinen, T., Kuha, J., & Karjalainen, J. (2015). Empirical Estimation of Accumulation-Induced Change in Gill Net Catch-ability : Mind the Observation Errors. The Open Fish Science Journal, 8, 13-22. https://doi.org/10.2174/1874401X01508010013
Published in
The Open Fish Science JournalDate
2015Copyright
© This is an open access article distributed under the terms of the Creative Commons Attribution License.
We analyzed cumulative catches for 24 h gill net exposures divided into 4*6 h, 2*12 h and 1*24 h soak time treatments to estimate the reduction in its catchability due to accumulation of fish. The effects of loss of catch during net lifting, disturbance effect and fouling were eliminated as far as possible to reveal the true effect of accumulation. First we applied simple nonparametric and parametric tests in comparison of treatments. As expected, considerable reduction in catchability took place along with the increase in soak time, indicated by significantly lower total 24 h catches from longer soaks in comparison with shorter ones. The reduction was more pronounced for roach than for perch. Further, we compared a functional relationship regression (FRR), admitting correctly observation error variance also in the x-axis variable, with ordinary least squares regression (OLS) in modelling the relationship between cumulative 24 h catches for different treatments. We estimated the between-replicates proportional observation error variance within a treatment and found it to be similar in different treatments. Therefore the variance ratio could be assumed to be close to 1 enabling the use of major axis solution FRR. In this particular case the incorrect use of OLS obviously gives a seriously biased result, exacerbating the negative effect of accumulation for high x-axis values in comparison with FRR. We recommend the use of FRR for any analysis comparing different notoriously low precision fish abundance proxies.
...
![showless](/themes/JYX2//images/showless.png)
![showmore](/themes/JYX2//images/showmore.png)
Publisher
Bentham Science PublishersISSN Search the Publication Forum
1874-401X
Original source
http://benthamopen.com/contents/pdf/TOFISHSJ/TOFISHSJ-8-13.pdfPublication in research information system
https://converis.jyu.fi/converis/portal/detail/Publication/25229126
Metadata
Show full item recordCollections
License
Except where otherwise noted, this item's license is described as © This is an open access article distributed under the terms of the Creative Commons Attribution License.
Related items
Showing items with similar title or keywords.
-
Poverty, inequality and the Finnish 1860s famine
Voutilainen, Miikka (University of Jyväskylä, 2016) -
Perhe, työttömyys ja lama
Virmasalo, Ilkka (Jyväskylän yliopisto, 2002)Huono-osaisuus työmarkkinoilla kasautuu perheisiin. Näin ollen voidaan kärjistetysti sanoa perheen olevan joillekin ongelma. Työttömyyden kasautumisen ongelman alkua on vaikea osoittaa, mutta kyse ei ole yksinomaan ... -
Behaviour of sediment-associated silver nanoparticles and their toxicity to Lumbriculus variegatus
Rajala, Juho (University of Jyväskylä, 2017)The increasing use of silver nanoparticles (AgNPs) in industry and consumer products results in the increasing environmental concentrations of AgNPs. In the aquatic environment, sediment is the major sink for the AgNPs. ... -
Aluetaloustieteen menetelmät liikennejärjestelmän kehittämisen vaikutustarkastelussa
Hokkanen, Joonas; Savikko, Heikki; Honkatukia, Juha; Metsäranta, Heikki; Sirkiä, Ari; Haapanen, Mika; Tohmo, Timo (Liikenne- ja viestintäministeriö, 2020)Tässä selvityksessä on arvioitu, voidaanko aluetaloudellisilla tarkasteluilla selvittää liikenneinfrastruktuurien kehittämiseen sekä liikenteen hinnoitteluun ja sääntelyyn liittyvien toimenpiteiden vaikutuksia yrityksille, ... -
Blackfly Larvae (Simulium spp.) Can Intensify Methylmercury Biomagnification in Boreal Food Webs
Karjalainen, Anna K.; Salmelin, Johanna; Dimock, Brian; Hintelmann, Holger (Springer, 2020)Global pollution of mercury (Hg) threatens ecosystem and human health. We measured total Hg (THg) and monomethylmercury (MMHg) concentrations in filter-feeding blackfly (Simulium spp.) larvae in the inflows and the outflows ...