Movements and Growth Rates of Yellow‐Phase American Eels in the Annaquatucket River, Rhode Island

• Published in: Transactions of the American Fisheries Society (1900) 1997-07, Vol.126 (4), p.638-646
• Main Author: Oliveira, Kenneth
• Format: Article
• Language: English
• Subjects: Agnatha. Pisces; Anguilla rostrata; Animal and plant ecology; Animal, plant and microbial ecology; Animals; Biological and medical sciences; Brackish; Demecology; Freshwater; Fundamental and applied biological sciences. Psychology; Vertebrata
• ISSN: 0002-8487; 1548-8659
• DOI: 10.1577/1548-8659(1997)126<0638:MAGROY>2.3.CO;2

Eight hundred twenty nine yellow‐phase American eels Anguilla rostrata, 160–740 mm total length (TL), were electrofished from 10 stations in the Annaquatucket River, Rhode Island. The eels were individually marked with liquid‐nitrogen‐cooled brands and released at the site of collection. Resampling yielded 200 recaptures (24%); eels were recaptured at 8 of the 10 stations after 1 year. Of all recaptures, 174 (87%) were from the station of release, indicating restricted movement by American eels from the collection sites. Stations associated with dams had higher recapture rates, but there was no significant relationship between percent recaptured and eel density, station size, or distance upriver. An annual growth rate (mean ± SE) of 29.9 ± 4.7 mm/year for all American eels was estimated for a 214‐d growing season. The growth rate for eels longer than 399 mm TL, which have previously been shown to be female, was 62.10 ± 14.9 mm/year, 2.3 times greater than for eels less than 400 mm. Mean growth rates do not appear to be a function of distance upriver or density but are more closely related to the sex ratio of eels at the station. Comparison of these growth rates with other published growth rates suggests that both sex ratio and latitude are important factors influencing the growth rate of a given population.