INVESTIGADORES
CUSSAC Victor Enrique
artículos
Título:
Distribution of introduced and native fish in Patagonia (Argentina): patterns and changes in fish assemblages
Autor/es:
AIGO J,; V CUSSAC; S PERIS; S ORTUBAY; S GÓMEZ; H LÓPEZ; M GROSS; J BARRIGA; M BATTINI
Revista:
REVIEWS IN FISH BIOLOGY AND FISHERIES
Editorial:
Springer
Referencias:
Año: 2008 vol. 18 p. 387 - 408
ISSN:
0960-3166
Resumen:
Abstract The interaction between native fishes and
salmonids introduced in Patagonia at the beginning of
the 20th Century, developed at the same time as the
environmental change. The phenomenon of global
warming has led to the formulation of predictions in
relation to changes in the distribution of species, in
the latitudinal dimension, both at intralacustrine, or
small streams levels. The aim of the present work
includes three main objectives: a) to compose a
general and updated picture of the latitudinal distribution
range of native and alien fishes, b) to analyze
the historical changes in the relative abundance of
Percichthys trucha, Odontesthes sp., and salmonids
in lakes and reservoirs, and c) to relate the diversity
and relative abundance of native and salmonid fishes
to the environmental variables of lakes and reservoirs.
We analysed previous records and an ensemble
of data about new locations along the northern border
of the Patagonian Province. We compared current
data about the relative abundance of native fishes and
salmonids in lakes and reservoirs, with previous
databases (19841987). All samplings considered
were performed during spring-summer surveys and
include relative abundance, as proportions of salmonids,
P. trucha, and Odontesthes sp. For the first time,
we found changes in fish assemblages from twenty
years back up to the present: a significant decline in
the relative abundances of salmonids and an increase
of P. trucha. We studied the association between the
diversity and relative abundance of native and
salmonid fishes and the environmental variables of
lakes and reservoirs using Canonical Correspondence
Analysis. Relative abundance showed mainly geographical
cues and the diversity relied largely on
morphometric characteristics. Relative abundance
and diversity seem to have a common point in the
lake area, included into the PAR concept. Native
abundance and alien diversity were negatively related
with latitude. Greater native diversity was observed
in lakes with high PAR compared with salmonids.
Historical changes such as southward dispersion,
relative abundance changes, and geographical
patterns for relative abundance and diversity are
basic concepts needed not only in future research but
also in management design for Patagonian fish
populations.