Size, Development of Pigment, Upstream Migration, and Relative Abundance of Young American Eels, Anguilla rostrata in a Coastal Rhode Island Stream
Progressive epidermal pigmentation of Anguilla rostrata elvers in a coastal Rhode Island stream was essentially identical to that described for A. anguilla, and proceeded rapidly in freshwater. Earlier arriving elvers averaged larger than those arriving later in the season, paralleling studies of Eu...
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ftunivrhodeislan:oai:digitalcommons.uri.edu:theses-1978 2023-07-30T04:05:28+02:00 Size, Development of Pigment, Upstream Migration, and Relative Abundance of Young American Eels, Anguilla rostrata in a Coastal Rhode Island Stream Haro, Alexander J. 1985-01-01T08:00:00Z application/pdf https://digitalcommons.uri.edu/theses/971 https://doi.org/10.23860/thesis-haro-alexander-1985 https://digitalcommons.uri.edu/context/theses/article/1978/viewcontent/thesis_haro_1985.pdf unknown DigitalCommons@URI https://digitalcommons.uri.edu/theses/971 doi:10.23860/thesis-haro-alexander-1985 https://digitalcommons.uri.edu/context/theses/article/1978/viewcontent/thesis_haro_1985.pdf Open Access Master's Theses text 1985 ftunivrhodeislan https://doi.org/10.23860/thesis-haro-alexander-1985 2023-07-17T18:38:42Z Progressive epidermal pigmentation of Anguilla rostrata elvers in a coastal Rhode Island stream was essentially identical to that described for A. anguilla, and proceeded rapidly in freshwater. Earlier arriving elvers averaged larger than those arriving later in the season, paralleling studies of European elvers. Mean total lengths of elvers collected in 1984 were significantly greater than those for 1983 and are the largest recorded for the Western North Atlantic. These differences may be due to sampling technique. Migration of elvers into freshwater may be induced by decreasing flow rates and/or increasing stream temperatures. The relatively slow upstream migration of elvers in the lower section of the stream (approximately 200 m per month) is attributed to high stream gradient and the presence of obstructions. By late summer and early fall, elvers (age I+) had acquired the coloration typical of yellow eels and had grown 20 to 30 mm larger than elvers arriving in freshwater in late winter and spring. The frequency of II+ and older eels increased with increasing distance from the tidal zone. This indicates that the upstream migration of elvers is limited, and that the colonization of inland waters is accomplished mainly by yellow eels in their second and later years of continental life. Text North Atlantic University of Rhode Island: DigitalCommons@URI |
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Open Polar |
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University of Rhode Island: DigitalCommons@URI |
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ftunivrhodeislan |
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unknown |
description |
Progressive epidermal pigmentation of Anguilla rostrata elvers in a coastal Rhode Island stream was essentially identical to that described for A. anguilla, and proceeded rapidly in freshwater. Earlier arriving elvers averaged larger than those arriving later in the season, paralleling studies of European elvers. Mean total lengths of elvers collected in 1984 were significantly greater than those for 1983 and are the largest recorded for the Western North Atlantic. These differences may be due to sampling technique. Migration of elvers into freshwater may be induced by decreasing flow rates and/or increasing stream temperatures. The relatively slow upstream migration of elvers in the lower section of the stream (approximately 200 m per month) is attributed to high stream gradient and the presence of obstructions. By late summer and early fall, elvers (age I+) had acquired the coloration typical of yellow eels and had grown 20 to 30 mm larger than elvers arriving in freshwater in late winter and spring. The frequency of II+ and older eels increased with increasing distance from the tidal zone. This indicates that the upstream migration of elvers is limited, and that the colonization of inland waters is accomplished mainly by yellow eels in their second and later years of continental life. |
format |
Text |
author |
Haro, Alexander J. |
spellingShingle |
Haro, Alexander J. Size, Development of Pigment, Upstream Migration, and Relative Abundance of Young American Eels, Anguilla rostrata in a Coastal Rhode Island Stream |
author_facet |
Haro, Alexander J. |
author_sort |
Haro, Alexander J. |
title |
Size, Development of Pigment, Upstream Migration, and Relative Abundance of Young American Eels, Anguilla rostrata in a Coastal Rhode Island Stream |
title_short |
Size, Development of Pigment, Upstream Migration, and Relative Abundance of Young American Eels, Anguilla rostrata in a Coastal Rhode Island Stream |
title_full |
Size, Development of Pigment, Upstream Migration, and Relative Abundance of Young American Eels, Anguilla rostrata in a Coastal Rhode Island Stream |
title_fullStr |
Size, Development of Pigment, Upstream Migration, and Relative Abundance of Young American Eels, Anguilla rostrata in a Coastal Rhode Island Stream |
title_full_unstemmed |
Size, Development of Pigment, Upstream Migration, and Relative Abundance of Young American Eels, Anguilla rostrata in a Coastal Rhode Island Stream |
title_sort |
size, development of pigment, upstream migration, and relative abundance of young american eels, anguilla rostrata in a coastal rhode island stream |
publisher |
DigitalCommons@URI |
publishDate |
1985 |
url |
https://digitalcommons.uri.edu/theses/971 https://doi.org/10.23860/thesis-haro-alexander-1985 https://digitalcommons.uri.edu/context/theses/article/1978/viewcontent/thesis_haro_1985.pdf |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Open Access Master's Theses |
op_relation |
https://digitalcommons.uri.edu/theses/971 doi:10.23860/thesis-haro-alexander-1985 https://digitalcommons.uri.edu/context/theses/article/1978/viewcontent/thesis_haro_1985.pdf |
op_doi |
https://doi.org/10.23860/thesis-haro-alexander-1985 |
_version_ |
1772817391927951360 |