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New Zealand Journal of Marine and Freshwater Research abstractsGrowth, survival, and recruitment of juvenile shortfinned eels (Anguilla australis) in a large New Zealand coastal lakeEric GraynothDonald J. JellymanNational Institute of Water & Atmospheric
Abstract Annual changes in the size composition and relative abundance of juvenile shortfinned eels (Anguilla australis Richardson) in Lake Ellesmere, New Zealand, were studied. Juveniles (<300 mm) were captured using a small beam trawl from 1994 to 1999. Age and growth rates were determined from otoliths and validated from trends in the length frequency of different year classes. Growth in length was linear from age 1 year onwards. Mean annual growth rates declined in recent years to exceptionally low values, averaging 13.2 mm year–1 (range 6.3–22.9 mm year–1 ), and are probably limited by the lack of food. Juvenile eels had high survival rates, exceeding 0.80 year–1 and were probably close to 1.0 year–1 . Recruitment into this shallow, turbid, brackish lake was variable and was correlated with the duration and timing of the lake’s opening to the sea. The decline in growth rates and restricted recruitment in recent years could reduce commercial catches of migrating silver eels for the next 10–15 years. Keywords shortfinned eels; Anguilla australis; lowland lakes; age; growth; recruitment; survival M01042 Received 10 May 2001; accepted 20 November 2001 PDF file of entire paper: Print-quality This year's abstracts | Journal home page | All abstracts | Publishing home page |