A review of age estimation in macrourid fishes with new data on age validation of juveniles

It was a long held belief that the constancy of the deep-water environment would result in continuous growth and all year round reproduction in deep-water fish. However. rings on scales and otoliths of deep-water fishes similar to those found in shallow-water fish species have been reported since the beginning of the 20th century. The development of a fishery for Coryphaenoides rupestris in the 1960s led to the use of scales and otoliths for age estimation without any attempt to validate the annual nature of the growth zones. This paper reviews the literature on age estimation in macrourid fishes. New data on the validation of age estimates of juvenile macrourids are presented. The species studied are all from the eastern North Atlantic and span a depth range from about 250 to 5000 m. A common feature is the apparent delay in the onset of the growing season until the autumn and winter months, which is possibly linked to food availability in the deep sea. (C) 2001 Elsevier Science B.V. All rights reserved.