Some aspects of the biology of the stargazer mountain catfish, Amphilius uranoscopus (pfeffer); (Siluriformes: Amphiliidae) indigenous to Kenya streams
Identifieur interne : 001538 ( Istex/Corpus ); précédent : 001537; suivant : 001539Some aspects of the biology of the stargazer mountain catfish, Amphilius uranoscopus (pfeffer); (Siluriformes: Amphiliidae) indigenous to Kenya streams
Auteurs : Charles C. Ngugi ; Julius O. Manyala ; Murithi Njiru ; Chrisestom M. MlewaSource :
- African Journal of Ecology [ 0141-6707 ] ; 2009-12.
English descriptors
- KwdEn :
- African streams, Amphilius, Amphilius uranoscopus, April, Aquatic sciences, Asymptotic length, August, Blackwell publishing, Body weight, Brown trout, Condition factor, December, East africa, Ecol, Environmental conditions, Exotic rainbow trout, February, Females males, Fish biol, Fork length, Gonad weight, Growth curvature, Growth parameters, Growth performance, Hauer lamberti, Headwater streams, High conductivity, High silt load, Journal compilation, Kenya, Kenya streams, Mountain populations, Moyle cech, Multiple comparison, Native species, Natural mortality, Ngugi, Oncorhynchus mykiss, Other months, Population sizes, Rainbow trout, Skelton, Southern africa, Specimens bmnh, Stargazer mountain, Summary data, Surface velocity, Tana river, Thego, Thego river, Thego stream, Trout, Uranoscopus, Water streams.
- Teeft :
- African streams, Amphilius, Amphilius uranoscopus, April, Aquatic sciences, Asymptotic length, August, Blackwell publishing, Body weight, Brown trout, Condition factor, December, East africa, Ecol, Environmental conditions, Exotic rainbow trout, February, Females males, Fish biol, Fork length, Gonad weight, Growth curvature, Growth parameters, Growth performance, Hauer lamberti, Headwater streams, High conductivity, High silt load, Journal compilation, Kenya, Kenya streams, Mountain populations, Moyle cech, Multiple comparison, Native species, Natural mortality, Ngugi, Oncorhynchus mykiss, Other months, Population sizes, Rainbow trout, Skelton, Southern africa, Specimens bmnh, Stargazer mountain, Summary data, Surface velocity, Tana river, Thego, Thego river, Thego stream, Trout, Uranoscopus, Water streams.
Abstract
A study on some biological parameters of the mountain catfish, Amphilius uranoscopus Pfeffer 1889 (Silurifomes: Amphiliidae), was carried out in the Thego stream on the slopes of Mount Kenya from February to December 2002. Physical and chemical profiles of the Thego show that the water quality parameters is typical of high altitude streams with temperatures rarely exceeding 18°C, DO ranging from 7.9 to 8.2 mg l−1 and relatively high conductivity (97–137 μS cm−1) typical of perturbed lotic environments. A total of 1010 fish were caught by an electro‐fisher, with sizes ranging between 8 and 24 cm fork length. The population structure had a unimodal distribution with maxima at 14–16 cm. The length–weight relationship showed relatively narrow range in the slope ranging from 2.61 in April to 2.98 in February 2002, thereby suggesting isometric growth pattern. The fitted growth pattern of A. uranoscopus showed an asymptotic length (L∞) of 28.5 cm and a growth curvature (K) of 0.56 year−1 resulting in an estimated natural mortality coefficient (M) of 0.90 year−1. The Fulton’s condition factor (K) was also relatively stable with a peak in April (0.92 ± 0.21) and lowest value in June (0.86 ± 0.10). As A. uranoscopus is not under commercial exploitation, the seemingly depressed population is possibly attributed to the introduced exotic rainbow trout that heavily predates on the species and environmental perturbations arising from changes in land use. The implications of such changes on A. uranoscopus are discussed.
Url:
DOI: 10.1111/j.1365-2028.2009.01032.x
Links to Exploration step
ISTEX:2BE4AF5AFEB0F97A2C32F4BF00D38C6C4A770F98Le document en format XML
<record><TEI wicri:istexFullTextTei="biblStruct"><teiHeader><fileDesc><titleStmt><title xml:lang="en">Some aspects of the biology of the stargazer mountain catfish, Amphilius uranoscopus (pfeffer); (Siluriformes: Amphiliidae) indigenous to Kenya streams</title><author><name sortKey="Ngugi, Charles C" sort="Ngugi, Charles C" uniqKey="Ngugi C" first="Charles C." last="Ngugi">Charles C. Ngugi</name><affiliation><mods:affiliation>E-mail: cngugi@africaonline.co.ke</mods:affiliation></affiliation></author><author><name sortKey="Manyala, Julius O" sort="Manyala, Julius O" uniqKey="Manyala J" first="Julius O." last="Manyala">Julius O. Manyala</name><affiliation><mods:affiliation>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya</mods:affiliation></affiliation></author><author><name sortKey="Njiru, Murithi" sort="Njiru, Murithi" uniqKey="Njiru M" first="Murithi" last="Njiru">Murithi Njiru</name><affiliation><mods:affiliation>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya</mods:affiliation></affiliation></author><author><name sortKey="Mlewa, Chrisestom M" sort="Mlewa, Chrisestom M" uniqKey="Mlewa C" first="Chrisestom M." last="Mlewa">Chrisestom M. Mlewa</name><affiliation><mods:affiliation>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya</mods:affiliation></affiliation></author></titleStmt><publicationStmt><idno type="wicri:source">ISTEX</idno><idno type="RBID">ISTEX:2BE4AF5AFEB0F97A2C32F4BF00D38C6C4A770F98</idno><date when="2009" year="2009">2009</date><idno type="doi">10.1111/j.1365-2028.2009.01032.x</idno><idno type="url">https://api.istex.fr/document/2BE4AF5AFEB0F97A2C32F4BF00D38C6C4A770F98/fulltext/pdf</idno><idno type="wicri:Area/Istex/Corpus">001538</idno><idno type="wicri:explorRef" wicri:stream="Istex" wicri:step="Corpus" wicri:corpus="ISTEX">001538</idno></publicationStmt><sourceDesc><biblStruct><analytic><title level="a" type="main">Some aspects of the biology of the stargazer mountain catfish, <hi rend="italic">Amphilius uranoscopus</hi> (pfeffer); (Siluriformes: Amphiliidae) indigenous to Kenya streams</title><author><name sortKey="Ngugi, Charles C" sort="Ngugi, Charles C" uniqKey="Ngugi C" first="Charles C." last="Ngugi">Charles C. Ngugi</name><affiliation><mods:affiliation>E-mail: cngugi@africaonline.co.ke</mods:affiliation></affiliation></author><author><name sortKey="Manyala, Julius O" sort="Manyala, Julius O" uniqKey="Manyala J" first="Julius O." last="Manyala">Julius O. Manyala</name><affiliation><mods:affiliation>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya</mods:affiliation></affiliation></author><author><name sortKey="Njiru, Murithi" sort="Njiru, Murithi" uniqKey="Njiru M" first="Murithi" last="Njiru">Murithi Njiru</name><affiliation><mods:affiliation>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya</mods:affiliation></affiliation></author><author><name sortKey="Mlewa, Chrisestom M" sort="Mlewa, Chrisestom M" uniqKey="Mlewa C" first="Chrisestom M." last="Mlewa">Chrisestom M. Mlewa</name><affiliation><mods:affiliation>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya</mods:affiliation></affiliation></author></analytic><monogr></monogr><series><title level="j" type="main">African Journal of Ecology</title><title level="j" type="alt">AFRICAN JOURNAL ECOLOGY</title><idno type="ISSN">0141-6707</idno><idno type="eISSN">1365-2028</idno><imprint><biblScope unit="vol">47</biblScope><biblScope unit="issue">4</biblScope><biblScope unit="page" from="606">606</biblScope><biblScope unit="page" to="613">613</biblScope><biblScope unit="page-count">8</biblScope><publisher>Blackwell Publishing Ltd</publisher><pubPlace>Oxford, UK</pubPlace><date type="published" when="2009-12">2009-12</date></imprint><idno type="ISSN">0141-6707</idno></series></biblStruct></sourceDesc><seriesStmt><idno type="ISSN">0141-6707</idno></seriesStmt></fileDesc><profileDesc><textClass><keywords scheme="KwdEn" xml:lang="en"><term>African streams</term><term>Amphilius</term><term>Amphilius uranoscopus</term><term>April</term><term>Aquatic sciences</term><term>Asymptotic length</term><term>August</term><term>Blackwell publishing</term><term>Body weight</term><term>Brown trout</term><term>Condition factor</term><term>December</term><term>East africa</term><term>Ecol</term><term>Environmental conditions</term><term>Exotic rainbow trout</term><term>February</term><term>Females males</term><term>Fish biol</term><term>Fork length</term><term>Gonad weight</term><term>Growth curvature</term><term>Growth parameters</term><term>Growth performance</term><term>Hauer lamberti</term><term>Headwater streams</term><term>High conductivity</term><term>High silt load</term><term>Journal compilation</term><term>Kenya</term><term>Kenya streams</term><term>Mountain populations</term><term>Moyle cech</term><term>Multiple comparison</term><term>Native species</term><term>Natural mortality</term><term>Ngugi</term><term>Oncorhynchus mykiss</term><term>Other months</term><term>Population sizes</term><term>Rainbow trout</term><term>Skelton</term><term>Southern africa</term><term>Specimens bmnh</term><term>Stargazer mountain</term><term>Summary data</term><term>Surface velocity</term><term>Tana river</term><term>Thego</term><term>Thego river</term><term>Thego stream</term><term>Trout</term><term>Uranoscopus</term><term>Water streams</term></keywords><keywords scheme="Teeft" xml:lang="en"><term>African streams</term><term>Amphilius</term><term>Amphilius uranoscopus</term><term>April</term><term>Aquatic sciences</term><term>Asymptotic length</term><term>August</term><term>Blackwell publishing</term><term>Body weight</term><term>Brown trout</term><term>Condition factor</term><term>December</term><term>East africa</term><term>Ecol</term><term>Environmental conditions</term><term>Exotic rainbow trout</term><term>February</term><term>Females males</term><term>Fish biol</term><term>Fork length</term><term>Gonad weight</term><term>Growth curvature</term><term>Growth parameters</term><term>Growth performance</term><term>Hauer lamberti</term><term>Headwater streams</term><term>High conductivity</term><term>High silt load</term><term>Journal compilation</term><term>Kenya</term><term>Kenya streams</term><term>Mountain populations</term><term>Moyle cech</term><term>Multiple comparison</term><term>Native species</term><term>Natural mortality</term><term>Ngugi</term><term>Oncorhynchus mykiss</term><term>Other months</term><term>Population sizes</term><term>Rainbow trout</term><term>Skelton</term><term>Southern africa</term><term>Specimens bmnh</term><term>Stargazer mountain</term><term>Summary data</term><term>Surface velocity</term><term>Tana river</term><term>Thego</term><term>Thego river</term><term>Thego stream</term><term>Trout</term><term>Uranoscopus</term><term>Water streams</term></keywords></textClass></profileDesc></teiHeader><front><div type="abstract" xml:lang="en">A study on some biological parameters of the mountain catfish, Amphilius uranoscopus Pfeffer 1889 (Silurifomes: Amphiliidae), was carried out in the Thego stream on the slopes of Mount Kenya from February to December 2002. Physical and chemical profiles of the Thego show that the water quality parameters is typical of high altitude streams with temperatures rarely exceeding 18°C, DO ranging from 7.9 to 8.2 mg l−1 and relatively high conductivity (97–137 μS cm−1) typical of perturbed lotic environments. A total of 1010 fish were caught by an electro‐fisher, with sizes ranging between 8 and 24 cm fork length. The population structure had a unimodal distribution with maxima at 14–16 cm. The length–weight relationship showed relatively narrow range in the slope ranging from 2.61 in April to 2.98 in February 2002, thereby suggesting isometric growth pattern. The fitted growth pattern of A. uranoscopus showed an asymptotic length (L∞) of 28.5 cm and a growth curvature (K) of 0.56 year−1 resulting in an estimated natural mortality coefficient (M) of 0.90 year−1. The Fulton’s condition factor (K) was also relatively stable with a peak in April (0.92 ± 0.21) and lowest value in June (0.86 ± 0.10). As A. uranoscopus is not under commercial exploitation, the seemingly depressed population is possibly attributed to the introduced exotic rainbow trout that heavily predates on the species and environmental perturbations arising from changes in land use. The implications of such changes on A. uranoscopus are discussed.</div></front></TEI><istex><corpusName>wiley</corpusName><keywords><teeft><json:string>uranoscopus</json:string><json:string>thego</json:string><json:string>kenya</json:string><json:string>amphilius</json:string><json:string>february</json:string><json:string>skelton</json:string><json:string>april</json:string><json:string>ecol</json:string><json:string>fork length</json:string><json:string>ngugi</json:string><json:string>condition factor</json:string><json:string>december</json:string><json:string>journal compilation</json:string><json:string>blackwell publishing</json:string><json:string>august</json:string><json:string>thego stream</json:string><json:string>rainbow trout</json:string><json:string>asymptotic length</json:string><json:string>amphilius uranoscopus</json:string><json:string>mountain populations</json:string><json:string>kenya streams</json:string><json:string>natural mortality</json:string><json:string>other months</json:string><json:string>gonad weight</json:string><json:string>growth parameters</json:string><json:string>population sizes</json:string><json:string>growth performance</json:string><json:string>southern africa</json:string><json:string>tana river</json:string><json:string>headwater streams</json:string><json:string>specimens bmnh</json:string><json:string>moyle cech</json:string><json:string>aquatic sciences</json:string><json:string>hauer lamberti</json:string><json:string>surface velocity</json:string><json:string>body weight</json:string><json:string>multiple comparison</json:string><json:string>thego river</json:string><json:string>oncorhynchus mykiss</json:string><json:string>exotic rainbow trout</json:string><json:string>high conductivity</json:string><json:string>females males</json:string><json:string>summary data</json:string><json:string>growth curvature</json:string><json:string>environmental conditions</json:string><json:string>high silt load</json:string><json:string>african streams</json:string><json:string>native species</json:string><json:string>brown trout</json:string><json:string>stargazer mountain</json:string><json:string>water streams</json:string><json:string>fish biol</json:string><json:string>east africa</json:string><json:string>trout</json:string></teeft></keywords><author><json:item><name>Charles C. Ngugi</name><affiliations><json:string>E-mail: cngugi@africaonline.co.ke</json:string></affiliations></json:item><json:item><name>Julius O. Manyala</name><affiliations><json:string>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya</json:string></affiliations></json:item><json:item><name>Murithi Njiru</name><affiliations><json:string>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya</json:string></affiliations></json:item><json:item><name>Chrisestom M. Mlewa</name><affiliations><json:string>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya</json:string></affiliations></json:item></author><subject><json:item><lang><json:string>eng</json:string></lang><value>catfish</value></json:item><json:item><lang><json:string>eng</json:string></lang><value>growth</value></json:item><json:item><lang><json:string>eng</json:string></lang><value>Kenya streams</value></json:item><json:item><lang><json:string>eng</json:string></lang><value>population sizes</value></json:item></subject><articleId><json:string>AJE1032</json:string></articleId><arkIstex>ark:/67375/WNG-F4HG4VWT-K</arkIstex><language><json:string>eng</json:string></language><originalGenre><json:string>article</json:string></originalGenre><abstract>A study on some biological parameters of the mountain catfish, Amphilius uranoscopus Pfeffer 1889 (Silurifomes: Amphiliidae), was carried out in the Thego stream on the slopes of Mount Kenya from February to December 2002. Physical and chemical profiles of the Thego show that the water quality parameters is typical of high altitude streams with temperatures rarely exceeding 18°C, DO ranging from 7.9 to 8.2 mg l−1 and relatively high conductivity (97–137 μS cm−1) typical of perturbed lotic environments. A total of 1010 fish were caught by an electro‐fisher, with sizes ranging between 8 and 24 cm fork length. The population structure had a unimodal distribution with maxima at 14–16 cm. The length–weight relationship showed relatively narrow range in the slope ranging from 2.61 in April to 2.98 in February 2002, thereby suggesting isometric growth pattern. The fitted growth pattern of A. uranoscopus showed an asymptotic length (L∞) of 28.5 cm and a growth curvature (K) of 0.56 year−1 resulting in an estimated natural mortality coefficient (M) of 0.90 year−1. The Fulton’s condition factor (K) was also relatively stable with a peak in April (0.92 ± 0.21) and lowest value in June (0.86 ± 0.10). As A. uranoscopus is not under commercial exploitation, the seemingly depressed population is possibly attributed to the introduced exotic rainbow trout that heavily predates on the species and environmental perturbations arising from changes in land use. The implications of such changes on A. uranoscopus are discussed.</abstract><qualityIndicators><score>8.873</score><pdfWordCount>4149</pdfWordCount><pdfCharCount>25523</pdfCharCount><pdfVersion>1.3</pdfVersion><pdfPageCount>8</pdfPageCount><pdfPageSize>595.276 x 782.362 pts</pdfPageSize><refBibsNative>true</refBibsNative><abstractWordCount>227</abstractWordCount><abstractCharCount>1529</abstractCharCount><keywordCount>4</keywordCount></qualityIndicators><title>Some aspects of the biology of the stargazer mountain catfish, Amphilius uranoscopus (pfeffer); (Siluriformes: Amphiliidae) indigenous to Kenya streams</title><genre><json:string>article</json:string></genre><host><title>African Journal of Ecology</title><language><json:string>unknown</json:string></language><doi><json:string>10.1111/(ISSN)1365-2028</json:string></doi><issn><json:string>0141-6707</json:string></issn><eissn><json:string>1365-2028</json:string></eissn><publisherId><json:string>AJE</json:string></publisherId><volume>47</volume><issue>4</issue><pages><first>606</first><last>613</last><total>8</total></pages><genre><json:string>journal</json:string></genre></host><namedEntities><unitex><date><json:string>2009</json:string><json:string>1010</json:string><json:string>between February 2002 and December 2002</json:string><json:string>2002</json:string><json:string>1867</json:string><json:string>1910</json:string><json:string>1864</json:string></date><geogName><json:string>Thego River</json:string><json:string>Mount Kenya</json:string><json:string>Zambezi</json:string><json:string>Athi River</json:string><json:string>River Thego</json:string></geogName><orgName><json:string>Minitab Inc.</json:string><json:string>Department of Public Health Engineering, University of Newcastle</json:string><json:string>Ethiopia, Tanzania and Kenya</json:string><json:string>Hanna Instruments, Germany</json:string><json:string>Yellow Springs Instruments Company Inc.</json:string><json:string>Moi University</json:string><json:string>Blackwell Publishing Ltd</json:string><json:string>Mount Kenya and Taita</json:string><json:string>Fishbase</json:string><json:string>Kenya Abstract A</json:string></orgName><orgName_funder></orgName_funder><orgName_provider></orgName_provider><persName><json:string>Thego</json:string><json:string>Vernon Hills</json:string><json:string>Information</json:string><json:string>U.S.A. Conductivity</json:string><json:string>J. Ecol</json:string><json:string>August Table</json:string><json:string>Julius O. Manyala</json:string><json:string>P. O. Box</json:string><json:string>Tana River</json:string></persName><placeName><json:string>Australia</json:string><json:string>Dayton</json:string><json:string>Kenya</json:string><json:string>U.S.</json:string><json:string>Jackson</json:string><json:string>Vancouver</json:string><json:string>America</json:string><json:string>South Africa</json:string><json:string>New Zealand</json:string><json:string>Velocity</json:string><json:string>WA</json:string><json:string>Nairobi</json:string><json:string>OH</json:string></placeName><ref_url></ref_url><ref_bibl><json:string>Moyle & Cech, 1996</json:string><json:string>Marriott et al. (1997)</json:string><json:string>Rinne & Wanjala, 1983</json:string><json:string>Bagenal & Braum, 1971</json:string><json:string>Gayanilo & Pauly, 1997</json:string><json:string>Leprieur et al. (2006)</json:string><json:string>Charles C. Ngugi et al.</json:string><json:string>and Owiti & Dadzie, 1989</json:string><json:string>Skelton (1993)</json:string><json:string>Skelton, 1984</json:string><json:string>Marriott et al., 1997</json:string><json:string>Marriott, Booth & Skelton, 1997</json:string><json:string>Greig (2006)</json:string><json:string>Ngugi & Green, 2001</json:string><json:string>Moyle and Cech, 1996</json:string><json:string>February 2002</json:string><json:string>FISHBASE, 2007</json:string><json:string>Onset Computer Corporation, 1996</json:string><json:string>Ngugi & Green, 2001, 2006</json:string><json:string>Skelton, 1993</json:string><json:string>Bruton, 1979</json:string><json:string>Golubtsov, Moots & Dzerjinskii, 2004</json:string><json:string>February and December 2002</json:string></ref_bibl><bibl></bibl></unitex></namedEntities><ark><json:string>ark:/67375/WNG-F4HG4VWT-K</json:string></ark><categories><wos><json:string>1 - science</json:string><json:string>2 - ecology</json:string></wos><scienceMetrix><json:string>1 - natural sciences</json:string><json:string>2 - biology</json:string><json:string>3 - ecology</json:string></scienceMetrix><scopus><json:string>1 - Life Sciences</json:string><json:string>2 - Agricultural and Biological Sciences</json:string><json:string>3 - Ecology, Evolution, Behavior and Systematics</json:string></scopus><inist><json:string>1 - sciences appliquees, technologies et medecines</json:string><json:string>2 - sciences biologiques et medicales</json:string><json:string>3 - sciences biologiques fondamentales et appliquees. psychologie</json:string></inist></categories><publicationDate>2009</publicationDate><copyrightDate>2009</copyrightDate><doi><json:string>10.1111/j.1365-2028.2009.01032.x</json:string></doi><id>2BE4AF5AFEB0F97A2C32F4BF00D38C6C4A770F98</id><score>1</score><fulltext><json:item><extension>pdf</extension><original>true</original><mimetype>application/pdf</mimetype><uri>https://api.istex.fr/document/2BE4AF5AFEB0F97A2C32F4BF00D38C6C4A770F98/fulltext/pdf</uri></json:item><json:item><extension>zip</extension><original>false</original><mimetype>application/zip</mimetype><uri>https://api.istex.fr/document/2BE4AF5AFEB0F97A2C32F4BF00D38C6C4A770F98/fulltext/zip</uri></json:item><istex:fulltextTEI uri="https://api.istex.fr/document/2BE4AF5AFEB0F97A2C32F4BF00D38C6C4A770F98/fulltext/tei"><teiHeader><fileDesc><titleStmt><title level="a" type="main">Some aspects of the biology of the stargazer mountain catfish, <hi rend="italic">Amphilius uranoscopus</hi> (pfeffer); (Siluriformes: Amphiliidae) indigenous to Kenya streams</title></titleStmt><publicationStmt><authority>ISTEX</authority><publisher>Blackwell Publishing Ltd</publisher><pubPlace>Oxford, UK</pubPlace><availability><licence>© 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd</licence></availability><date type="published" when="2009-12"></date></publicationStmt><notesStmt><note type="content-type" subtype="article" source="article" scheme="https://content-type.data.istex.fr/ark:/67375/XTP-6N5SZHKN-D">article</note><note type="publication-type" subtype="journal" scheme="https://publication-type.data.istex.fr/ark:/67375/JMC-0GLKJH51-B">journal</note></notesStmt><sourceDesc><biblStruct type="article"><analytic><title level="a" type="main">Some aspects of the biology of the stargazer mountain catfish, <hi rend="italic">Amphilius uranoscopus</hi> (pfeffer); (Siluriformes: Amphiliidae) indigenous to Kenya streams</title><title level="a" type="short">Mountain catfish populations in Kenya streams</title><author xml:id="author-0000" role="corresp"><persName><forename type="first">Charles C.</forename><surname>Ngugi</surname></persName><affiliation>*E‐mail: cngugi@africaonline.co.ke</affiliation></author><author xml:id="author-0001"><persName><forename type="first">Julius O.</forename><surname>Manyala</surname></persName><affiliation>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya<address><country key="KE"></country></address></affiliation></author><author xml:id="author-0002"><persName><forename type="first">Murithi</forename><surname>Njiru</surname></persName><affiliation>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya<address><country key="KE"></country></address></affiliation></author><author xml:id="author-0003"><persName><forename type="first">Chrisestom M.</forename><surname>Mlewa</surname></persName><affiliation>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya<address><country key="KE"></country></address></affiliation></author><idno type="istex">2BE4AF5AFEB0F97A2C32F4BF00D38C6C4A770F98</idno><idno type="ark">ark:/67375/WNG-F4HG4VWT-K</idno><idno type="DOI">10.1111/j.1365-2028.2009.01032.x</idno><idno type="unit">AJE1032</idno><idno type="toTypesetVersion">file:AJE.AJE1032.pdf</idno></analytic><monogr><title level="j" type="main">African Journal of Ecology</title><title level="j" type="alt">AFRICAN JOURNAL ECOLOGY</title><idno type="pISSN">0141-6707</idno><idno type="eISSN">1365-2028</idno><idno type="book-DOI">10.1111/(ISSN)1365-2028</idno><idno type="book-part-DOI">10.1111/aje.2009.47.issue-4</idno><idno type="product">AJE</idno><idno type="publisherDivision">ST</idno><imprint><biblScope unit="vol">47</biblScope><biblScope unit="issue">4</biblScope><biblScope unit="page" from="606">606</biblScope><biblScope unit="page" to="613">613</biblScope><biblScope unit="page-count">8</biblScope><publisher>Blackwell Publishing Ltd</publisher><pubPlace>Oxford, UK</pubPlace><date type="published" when="2009-12"></date></imprint></monogr></biblStruct></sourceDesc></fileDesc><profileDesc><abstract xml:lang="en" style="main"><head>Abstract</head><p>A study on some biological parameters of the mountain catfish, <hi rend="italic">Amphilius uranoscopus</hi> Pfeffer 1889 (Silurifomes: Amphiliidae), was carried out in the Thego stream on the slopes of Mount Kenya from February to December 2002. Physical and chemical profiles of the Thego show that the water quality parameters is typical of high altitude streams with temperatures rarely exceeding 18°C, DO ranging from 7.9 to 8.2 mg l<hi rend="superscript">−1</hi> and relatively high conductivity (97–137 μS cm<hi rend="superscript">−1</hi>) typical of perturbed lotic environments. A total of 1010 fish were caught by an electro‐fisher, with sizes ranging between 8 and 24 cm fork length. The population structure had a unimodal distribution with maxima at 14–16 cm. The length–weight relationship showed relatively narrow range in the slope ranging from 2.61 in April to 2.98 in February 2002, thereby suggesting isometric growth pattern. The fitted growth pattern of <hi rend="italic">A. uranoscopus</hi> showed an asymptotic length (L<hi rend="subscript">∞</hi>) of 28.5 cm and a growth curvature (<hi rend="italic">K</hi>) of 0.56 year<hi rend="superscript">−1</hi> resulting in an estimated natural mortality coefficient (<hi rend="italic">M</hi>) of 0.90 year<hi rend="superscript">−1</hi>. The Fulton’s condition factor (<hi rend="italic">K</hi>) was also relatively stable with a peak in April (0.92 ± 0.21) and lowest value in June (0.86 ± 0.10). As <hi rend="italic">A. uranoscopus</hi> is not under commercial exploitation, the seemingly depressed population is possibly attributed to the introduced exotic rainbow trout that heavily predates on the species and environmental perturbations arising from changes in land use. The implications of such changes on <hi rend="italic">A. uranoscopus</hi> are discussed.</p></abstract><abstract xml:lang="fr" style="main"><head>Résumé</head><p>Une étude de certains paramètres du poisson‐chat de montagne <hi rend="italic">Amphilius uranoscopus</hi> Pfeffer 1889 (Silurifomes: Amphiliidae) a été réalisée dans le courant du Thego, sur les pentes du mont Kenya entre février et décembre 2002. Le profil physique et chimique du Thego montre que les paramètres de la qualité de l’eau sont typiques des cours d’eau de haute altitude, avec une température qui dépasse rarement 18°C, un OD qui varie de 7,9 à 8,2 mg/l, et une conductivité relativement haute (87 à 137 μS/cm) typique d’environnements lotiques perturbés. Au total, 1 010 poissons ont été capturés au moyen d’une canne électrique, d’une taille allant de 8 à 24 cm de longueur à la fourche. La structure de la population avait une distribution unimodale avec des maxima de 14–16 cm. La relation longueur/poids présente une variation relativement étroite dans la pente, allant de 2,61 en avril à 2,98 en février 2002, ce qui suggère un schéma de croissance isométrique. Le schéma de croissance intégré d’<hi rend="italic">A. uranoscopus</hi> montre une longueur asymptotique (L<hi rend="subscript">∞</hi>) de 28,5 cm et une courbure de croissance (<hi rend="italic">K</hi>) de 0,56/an, résultant en un coefficient de mortalité naturelle estimé (<hi rend="italic">M</hi>) de 0,90/an. Le facteur de condition de Fulton (<hi rend="italic">K</hi>) était aussi relativement stable, avec un pic en avril (0,92 ± 0,21) et la valeur la plus basse en juin (0,86 ± 0,10). Puisque <hi rend="italic">A. uranoscopus</hi> ne fait pas l’objet d’une exploitation commerciale, la dépression apparente de la population doit peut‐être être attribuée à la truite arc‐en‐ciel, espèce exotique introduite qui se nourrit abondamment de l’espèce, et à des perturbations environnementales provoquées par des changements d’utilisation des terres. Les implications de tels changements pour <hi rend="italic">A. uranoscopus</hi> sont discutées.</p></abstract><textClass><keywords xml:lang="en"><term xml:id="k1">catfish</term><term xml:id="k2">growth</term><term xml:id="k3">Kenya streams</term><term xml:id="k4">population sizes</term></keywords><keywords rend="tocHeading1"><term>Original Articles</term></keywords></textClass><langUsage><language ident="en"></language></langUsage></profileDesc></teiHeader></istex:fulltextTEI><json:item><extension>txt</extension><original>false</original><mimetype>text/plain</mimetype><uri>https://api.istex.fr/document/2BE4AF5AFEB0F97A2C32F4BF00D38C6C4A770F98/fulltext/txt</uri></json:item></fulltext><metadata><istex:metadataXml wicri:clean="Wiley, elements deleted: body"><istex:xmlDeclaration>version="1.0" encoding="UTF-8" standalone="yes"</istex:xmlDeclaration><istex:document><component version="2.0" type="serialArticle" xml:lang="en"><header><publicationMeta level="product"><publisherInfo><publisherName>Blackwell Publishing Ltd</publisherName><publisherLoc>Oxford, UK</publisherLoc></publisherInfo><doi origin="wiley" registered="yes">10.1111/(ISSN)1365-2028</doi><issn type="print">0141-6707</issn><issn type="electronic">1365-2028</issn><idGroup><id type="product" value="AJE"></id><id type="publisherDivision" value="ST"></id></idGroup><titleGroup><title type="main" sort="AFRICAN JOURNAL ECOLOGY">African Journal of Ecology</title></titleGroup></publicationMeta><publicationMeta level="part" position="12004"><doi origin="wiley">10.1111/aje.2009.47.issue-4</doi><numberingGroup><numbering type="journalVolume" number="47">47</numbering><numbering type="journalIssue" number="4">4</numbering></numberingGroup><coverDate startDate="2009-12">December 2009</coverDate></publicationMeta><publicationMeta level="unit" type="article" position="19" status="forIssue"><doi origin="wiley">10.1111/j.1365-2028.2009.01032.x</doi><idGroup><id type="unit" value="AJE1032"></id></idGroup><countGroup><count type="pageTotal" number="8"></count></countGroup><titleGroup><title type="tocHeading1">Original Articles</title></titleGroup><copyright>© 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd</copyright><eventGroup><event type="firstOnline" date="2009-08-24"></event><event type="publishedOnlineFinalForm" date="2009-11-13"></event><event type="xmlConverted" agent="Converter:BPG_TO_WML3G version:2.3.5 mode:FullText source:FullText result:FullText" date="2010-04-09"></event><event type="xmlConverted" agent="Converter:WILEY_ML3G_TO_WILEY_ML3GV2 version:3.8.8" date="2014-01-02"></event><event type="xmlConverted" agent="Converter:WML3G_To_WML3G version:4.1.7 mode:FullText,remove_FC" date="2014-10-14"></event></eventGroup><numberingGroup><numbering type="pageFirst" number="606">606</numbering><numbering type="pageLast" number="613">613</numbering></numberingGroup><correspondenceTo>
*E‐mail: <email>cngugi@africaonline.co.ke</email></correspondenceTo><linkGroup><link type="toTypesetVersion" href="file:AJE.AJE1032.pdf"></link></linkGroup></publicationMeta><contentMeta><unparsedEditorialHistory>(Manuscript accepted 26 May 2008)</unparsedEditorialHistory><countGroup><count type="figureTotal" number="5"></count><count type="tableTotal" number="1"></count></countGroup><titleGroup><title type="main">Some aspects of the biology of the stargazer mountain catfish, <i>Amphilius uranoscopus</i> (pfeffer); (Siluriformes: Amphiliidae) indigenous to Kenya streams</title><title type="shortAuthors"><i>Charles C. Ngugi</i> et al.</title><title type="short"><i>Mountain catfish populations in Kenya streams</i></title></titleGroup><creators><creator creatorRole="author" xml:id="cr1" corresponding="yes"><personName><givenNames>Charles C.</givenNames><familyName>Ngugi</familyName></personName></creator><creator creatorRole="author" xml:id="cr2" affiliationRef="#aff-1-1"><personName><givenNames>Julius O.</givenNames><familyName>Manyala</familyName></personName></creator><creator creatorRole="author" xml:id="cr3" affiliationRef="#aff-1-1"><personName><givenNames>Murithi</givenNames><familyName>Njiru</familyName></personName></creator><creator creatorRole="author" xml:id="cr4" affiliationRef="#aff-1-1"><personName><givenNames>Chrisestom M.</givenNames><familyName>Mlewa</familyName></personName></creator></creators><affiliationGroup><affiliation xml:id="aff-1-1" countryCode="KE"><unparsedAffiliation>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya</unparsedAffiliation></affiliation></affiliationGroup><keywordGroup xml:lang="en"><keyword xml:id="k1">catfish</keyword><keyword xml:id="k2">growth</keyword><keyword xml:id="k3">Kenya streams</keyword><keyword xml:id="k4">population sizes</keyword></keywordGroup><abstractGroup><abstract type="main" xml:lang="en"><title type="main">Abstract</title><p>A study on some biological parameters of the mountain catfish, <i>Amphilius uranoscopus</i> Pfeffer 1889 (Silurifomes: Amphiliidae), was carried out in the Thego stream on the slopes of Mount Kenya from February to December 2002. Physical and chemical profiles of the Thego show that the water quality parameters is typical of high altitude streams with temperatures rarely exceeding 18°C, DO ranging from 7.9 to 8.2 mg l<sup>−1</sup> and relatively high conductivity (97–137 μS cm<sup>−1</sup>) typical of perturbed lotic environments. A total of 1010 fish were caught by an electro‐fisher, with sizes ranging between 8 and 24 cm fork length. The population structure had a unimodal distribution with maxima at 14–16 cm. The length–weight relationship showed relatively narrow range in the slope ranging from 2.61 in April to 2.98 in February 2002, thereby suggesting isometric growth pattern. The fitted growth pattern of <i>A. uranoscopus</i> showed an asymptotic length (L<sub>∞</sub>) of 28.5 cm and a growth curvature (<i>K</i>) of 0.56 year<sup>−1</sup> resulting in an estimated natural mortality coefficient (<i>M</i>) of 0.90 year<sup>−1</sup>. The Fulton’s condition factor (<i>K</i>) was also relatively stable with a peak in April (0.92 ± 0.21) and lowest value in June (0.86 ± 0.10). As <i>A. uranoscopus</i> is not under commercial exploitation, the seemingly depressed population is possibly attributed to the introduced exotic rainbow trout that heavily predates on the species and environmental perturbations arising from changes in land use. The implications of such changes on <i>A. uranoscopus</i> are discussed.</p></abstract><abstract type="main" xml:lang="fr"><title type="main">Résumé</title><p>Une étude de certains paramètres du poisson‐chat de montagne <i>Amphilius uranoscopus</i> Pfeffer 1889 (Silurifomes: Amphiliidae) a été réalisée dans le courant du Thego, sur les pentes du mont Kenya entre février et décembre 2002. Le profil physique et chimique du Thego montre que les paramètres de la qualité de l’eau sont typiques des cours d’eau de haute altitude, avec une température qui dépasse rarement 18°C, un OD qui varie de 7,9 à 8,2 mg/l, et une conductivité relativement haute (87 à 137 μS/cm) typique d’environnements lotiques perturbés. Au total, 1 010 poissons ont été capturés au moyen d’une canne électrique, d’une taille allant de 8 à 24 cm de longueur à la fourche. La structure de la population avait une distribution unimodale avec des maxima de 14–16 cm. La relation longueur/poids présente une variation relativement étroite dans la pente, allant de 2,61 en avril à 2,98 en février 2002, ce qui suggère un schéma de croissance isométrique. Le schéma de croissance intégré d’<i>A. uranoscopus</i> montre une longueur asymptotique (L<sub>∞</sub>) de 28,5 cm et une courbure de croissance (<i>K</i>) de 0,56/an, résultant en un coefficient de mortalité naturelle estimé (<i>M</i>) de 0,90/an. Le facteur de condition de Fulton (<i>K</i>) était aussi relativement stable, avec un pic en avril (0,92 ± 0,21) et la valeur la plus basse en juin (0,86 ± 0,10). Puisque <i>A. uranoscopus</i> ne fait pas l’objet d’une exploitation commerciale, la dépression apparente de la population doit peut‐être être attribuée à la truite arc‐en‐ciel, espèce exotique introduite qui se nourrit abondamment de l’espèce, et à des perturbations environnementales provoquées par des changements d’utilisation des terres. Les implications de tels changements pour <i>A. uranoscopus</i> sont discutées.</p></abstract></abstractGroup></contentMeta></header></component></istex:document></istex:metadataXml><mods version="3.6"><titleInfo lang="en"><title>Some aspects of the biology of the stargazer mountain catfish, Amphilius uranoscopus (pfeffer); (Siluriformes: Amphiliidae) indigenous to Kenya streams</title></titleInfo><titleInfo type="abbreviated" lang="en"><title>Mountain catfish populations in Kenya streams</title></titleInfo><titleInfo type="alternative" contentType="CDATA" lang="en"><title>Some aspects of the biology of the stargazer mountain catfish, Amphilius uranoscopus (pfeffer); (Siluriformes: Amphiliidae) indigenous to Kenya streams</title></titleInfo><name type="personal"><namePart type="given">Charles C.</namePart><namePart type="family">Ngugi</namePart><affiliation>E-mail: cngugi@africaonline.co.ke</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">Julius O.</namePart><namePart type="family">Manyala</namePart><affiliation>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">Murithi</namePart><namePart type="family">Njiru</namePart><affiliation>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">Chrisestom M.</namePart><namePart type="family">Mlewa</namePart><affiliation>Department of Fisheries and Aquatic Sciences, Moi University, P. O. Box 1125, Eldoret, Kenya</affiliation><role><roleTerm type="text">author</roleTerm></role></name><typeOfResource>text</typeOfResource><genre type="article" displayLabel="article" authority="ISTEX" authorityURI="https://content-type.data.istex.fr" valueURI="https://content-type.data.istex.fr/ark:/67375/XTP-6N5SZHKN-D">article</genre><originInfo><publisher>Blackwell Publishing Ltd</publisher><place><placeTerm type="text">Oxford, UK</placeTerm></place><dateIssued encoding="w3cdtf">2009-12</dateIssued><edition>(Manuscript accepted 26 May 2008)</edition><copyrightDate encoding="w3cdtf">2009</copyrightDate></originInfo><language><languageTerm type="code" authority="rfc3066">en</languageTerm><languageTerm type="code" authority="iso639-2b">eng</languageTerm></language><physicalDescription><extent unit="figures">5</extent><extent unit="tables">1</extent></physicalDescription><abstract lang="en">A study on some biological parameters of the mountain catfish, Amphilius uranoscopus Pfeffer 1889 (Silurifomes: Amphiliidae), was carried out in the Thego stream on the slopes of Mount Kenya from February to December 2002. Physical and chemical profiles of the Thego show that the water quality parameters is typical of high altitude streams with temperatures rarely exceeding 18°C, DO ranging from 7.9 to 8.2 mg l−1 and relatively high conductivity (97–137 μS cm−1) typical of perturbed lotic environments. A total of 1010 fish were caught by an electro‐fisher, with sizes ranging between 8 and 24 cm fork length. The population structure had a unimodal distribution with maxima at 14–16 cm. The length–weight relationship showed relatively narrow range in the slope ranging from 2.61 in April to 2.98 in February 2002, thereby suggesting isometric growth pattern. The fitted growth pattern of A. uranoscopus showed an asymptotic length (L∞) of 28.5 cm and a growth curvature (K) of 0.56 year−1 resulting in an estimated natural mortality coefficient (M) of 0.90 year−1. The Fulton’s condition factor (K) was also relatively stable with a peak in April (0.92 ± 0.21) and lowest value in June (0.86 ± 0.10). As A. uranoscopus is not under commercial exploitation, the seemingly depressed population is possibly attributed to the introduced exotic rainbow trout that heavily predates on the species and environmental perturbations arising from changes in land use. The implications of such changes on A. uranoscopus are discussed.</abstract><abstract lang="fr">Une étude de certains paramètres du poisson‐chat de montagne Amphilius uranoscopus Pfeffer 1889 (Silurifomes: Amphiliidae) a été réalisée dans le courant du Thego, sur les pentes du mont Kenya entre février et décembre 2002. Le profil physique et chimique du Thego montre que les paramètres de la qualité de l’eau sont typiques des cours d’eau de haute altitude, avec une température qui dépasse rarement 18°C, un OD qui varie de 7,9 à 8,2 mg/l, et une conductivité relativement haute (87 à 137 μS/cm) typique d’environnements lotiques perturbés. Au total, 1 010 poissons ont été capturés au moyen d’une canne électrique, d’une taille allant de 8 à 24 cm de longueur à la fourche. La structure de la population avait une distribution unimodale avec des maxima de 14–16 cm. La relation longueur/poids présente une variation relativement étroite dans la pente, allant de 2,61 en avril à 2,98 en février 2002, ce qui suggère un schéma de croissance isométrique. Le schéma de croissance intégré d’A. uranoscopus montre une longueur asymptotique (L∞) de 28,5 cm et une courbure de croissance (K) de 0,56/an, résultant en un coefficient de mortalité naturelle estimé (M) de 0,90/an. Le facteur de condition de Fulton (K) était aussi relativement stable, avec un pic en avril (0,92 ± 0,21) et la valeur la plus basse en juin (0,86 ± 0,10). Puisque A. uranoscopus ne fait pas l’objet d’une exploitation commerciale, la dépression apparente de la population doit peut‐être être attribuée à la truite arc‐en‐ciel, espèce exotique introduite qui se nourrit abondamment de l’espèce, et à des perturbations environnementales provoquées par des changements d’utilisation des terres. Les implications de tels changements pour A. uranoscopus sont discutées.</abstract><subject lang="en"><genre>keywords</genre><topic>catfish</topic><topic>growth</topic><topic>Kenya streams</topic><topic>population sizes</topic></subject><relatedItem type="host"><titleInfo><title>African Journal of Ecology</title></titleInfo><genre type="journal" authority="ISTEX" authorityURI="https://publication-type.data.istex.fr" valueURI="https://publication-type.data.istex.fr/ark:/67375/JMC-0GLKJH51-B">journal</genre><identifier type="ISSN">0141-6707</identifier><identifier type="eISSN">1365-2028</identifier><identifier type="DOI">10.1111/(ISSN)1365-2028</identifier><identifier type="PublisherID">AJE</identifier><part><date>2009</date><detail type="volume"><caption>vol.</caption><number>47</number></detail><detail type="issue"><caption>no.</caption><number>4</number></detail><extent unit="pages"><start>606</start><end>613</end><total>8</total></extent></part></relatedItem><identifier type="istex">2BE4AF5AFEB0F97A2C32F4BF00D38C6C4A770F98</identifier><identifier type="ark">ark:/67375/WNG-F4HG4VWT-K</identifier><identifier type="DOI">10.1111/j.1365-2028.2009.01032.x</identifier><identifier type="ArticleID">AJE1032</identifier><accessCondition type="use and reproduction" contentType="copyright">© 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd</accessCondition><recordInfo><recordContentSource authority="ISTEX" authorityURI="https://loaded-corpus.data.istex.fr" valueURI="https://loaded-corpus.data.istex.fr/ark:/67375/XBH-L0C46X92-X">wiley</recordContentSource><recordOrigin>Blackwell Publishing Ltd</recordOrigin></recordInfo></mods><json:item><extension>json</extension><original>false</original><mimetype>application/json</mimetype><uri>https://api.istex.fr/document/2BE4AF5AFEB0F97A2C32F4BF00D38C6C4A770F98/metadata/json</uri></json:item></metadata><serie></serie></istex></record>Pour manipuler ce document sous Unix (Dilib)
EXPLOR_STEP=$WICRI_ROOT/Wicri/Santé/explor/EdenteV2/Data/Istex/Corpus
HfdSelect -h $EXPLOR_STEP/biblio.hfd -nk 001538 | SxmlIndent | more
Ou
HfdSelect -h $EXPLOR_AREA/Data/Istex/Corpus/biblio.hfd -nk 001538 | SxmlIndent | more
Pour mettre un lien sur cette page dans le réseau Wicri
{{Explor lien
|wiki= Wicri/Santé
|area= EdenteV2
|flux= Istex
|étape= Corpus
|type= RBID
|clé= ISTEX:2BE4AF5AFEB0F97A2C32F4BF00D38C6C4A770F98
|texte= Some aspects of the biology of the stargazer mountain catfish, Amphilius uranoscopus (pfeffer); (Siluriformes: Amphiliidae) indigenous to Kenya streams
}}
| This area was generated with Dilib version V0.6.32. |  |