INVESTIGADORES
PASCUAL miguel Alberto
artículos
Título:
Intra-population variation in anadromy and reproductive lifespan in Oncorhynchus mykiss (Walbaum) introduced in the Santa Cruz River, Argentina
Autor/es:
RIVA ROSSI, C.M.; PASCUAL, M.A.; BABALUK, J.A.; GARCÍA ASOREY, M.; HALDEN, N.M.
Revista:
JOURNAL OF FISH BIOLOGY
Editorial:
WILEY-BLACKWELL PUBLISHING, INC
Referencias:
Año: 2007 vol. 70 p. 1780 - 1797
ISSN:
0022-1112
Resumen:
Scale patterns, maturational status and otolith microchemistry (strontium to calcium ratios)
were analysed in sympatric anadromous and non-anadromous rainbow trout Oncorhynchus
mykiss in the Santa Cruz River (Patagonia, Argentina) to investigate the life-history differences
of anadromous and non-anadromous lifestyles and the association between maternal origin and
progeny life history. The analyses revealed that both forms can give rise to one another,
indicating a single population with alternative phenotypes. Anadromous fish smolted at ages
2 and 3 years, matured after 1 to 2 years in the ocean, and survived up to 11 years, spawning up
to eight times. Non-anadromous fish survived up to 6 years, spawning up to three times. The
extended reproductive life span associated with anadromy in this river suggests that increased
energetic and physiological demands associated with ocean migration may not necessarily result
in reduced postspawning survival, as has been suggested for salmonids in general. Alternatively,
reduction in parity may be regarded as the evolutionary outcome of reproductive traits resulting
from the adoption of anadromy (i.e. augmented reproductive investment) coupled with longrange
migrations to and from the ocean. The life-history patterns of Santa Cruz River rainbow
trout provide a natural experiment for investigating the evolutionary transition and maintenance
of anadromy and non-anadromy within salmonid populations.Oncorhynchus
mykiss in the Santa Cruz River (Patagonia, Argentina) to investigate the life-history differences
of anadromous and non-anadromous lifestyles and the association between maternal origin and
progeny life history. The analyses revealed that both forms can give rise to one another,
indicating a single population with alternative phenotypes. Anadromous fish smolted at ages
2 and 3 years, matured after 1 to 2 years in the ocean, and survived up to 11 years, spawning up
to eight times. Non-anadromous fish survived up to 6 years, spawning up to three times. The
extended reproductive life span associated with anadromy in this river suggests that increased
energetic and physiological demands associated with ocean migration may not necessarily result
in reduced postspawning survival, as has been suggested for salmonids in general. Alternatively,
reduction in parity may be regarded as the evolutionary outcome of reproductive traits resulting
from the adoption of anadromy (i.e. augmented reproductive investment) coupled with longrange
migrations to and from the ocean. The life-history patterns of Santa Cruz River rainbow
trout provide a natural experiment for investigating the evolutionary transition and maintenance
of anadromy and non-anadromy within salmonid populations.in the Santa Cruz River (Patagonia, Argentina) to investigate the life-history differences
of anadromous and non-anadromous lifestyles and the association between maternal origin and
progeny life history. The analyses revealed that both forms can give rise to one another,
indicating a single population with alternative phenotypes. Anadromous fish smolted at ages
2 and 3 years, matured after 1 to 2 years in the ocean, and survived up to 11 years, spawning up
to eight times. Non-anadromous fish survived up to 6 years, spawning up to three times. The
extended reproductive life span associated with anadromy in this river suggests that increased
energetic and physiological demands associated with ocean migration may not necessarily result
in reduced postspawning survival, as has been suggested for salmonids in general. Alternatively,
reduction in parity may be regarded as the evolutionary outcome of reproductive traits resulting
from the adoption of anadromy (i.e. augmented reproductive investment) coupled with longrange
migrations to and from the ocean. The life-history patterns of Santa Cruz River rainbow
trout provide a natural experiment for investigating the evolutionary transition and maintenance
of anadromy and non-anadromy within salmonid populations.i.e. augmented reproductive investment) coupled with longrange
migrations to and from the ocean. The life-history patterns of Santa Cruz River rainbow
trout provide a natural experiment for investigating the evolutionary transition and maintenance
of anadromy and non-anadromy within salmonid populations.