Growth of Silver Eels ( Anguilla rostrata ) in Two Areas of Newfoundland

Abstract

Seaward-migrating American (silver) eels were collected with fyke nets in Dog Bay and Holyrood Bay on the northeast and south coasts of Newfoundland [Canada]. In both areas, silver eels evidently undertake their spawning migration at ages 9-18 yr (mean 12.9 yr), but the mean length and weight of eels from Dog Bay were significantly larger than those from Holyrood Bay. The smallest silver eel in the samples was 56.9 cm long, and all specimens were considered to be females because there are no records of males longer than 40 cm from Newfoundland waters. Growth of silver eels from the 2 areas was compared with the growth of silver and yellow (immature) eels from the Topsail area (near St. John's) in an earlier study. The size of the watersheds, inhabited by the eels prior to migration, may partly be reflected in the size of eels at the time of migration, because growth of eels was evidently faster in the area with the largest watershed than in the areas with smaller watersheds, probably reflecting variation in competition for food and space. Orbit diameter of silver eels from Newfoundland was larger than those of non-silver eels of the same size range from Lake Ontario, indicating that size of the eyes increases with onset of maturity.