| Resumo: |
Long tailed hake Macruronus magellanicus, is a demersal fish,distributed in the SW Atlantic Ocean, in Malvinas Current waters,from 36° and 55°S, mainly between 50m and 200m depth. The species is also distributed in Chilenian waters in the Pacific Ocean, being caught in the Magellan Strait and the Beagle Channel. Age determination was estimated with the sagittae otoliths, in which only one ring is formed during the year. Growth parameters were calculated directly and with back calculated methodology, no differences were observed between the results. Differences in growth sexes were evident from 3 years old. The oldest age observed was 13. Different distributional areas of adults through out the year could suggest a migratory movement in northern waters of the total distributional area, in deeper waters and near the Bahía Grande. On the other hand,the presence of juveniles in different areas of the continental shelf shallower than 100m, in the San Jorge Gulf, and near Tierra del Fuego e Isla de los Estados (Argentina), should indicate spawning and hatchering grounds. Total and natural mortality rates observed between 0.3 and 0.58 being considerably higher values for a long life species.
Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales.
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