Fishes

Investigators

Dr. Jerry Johnson, Brigham Young University
Dr. Guillermo Ortí, University of Nebraska
Dr. Daniel Ruzzante, Dalhousie University
Dr. Sandra Walde, Dalhousie University
Dr. Victor Cussac, Universidad Nacional del Comahue
Dr. Evelyn Habit, Universidad de Concepción

Patagonian Silverside

Photo courtesy of Rick Mayden Pejerrey patagónico (Odontesthes hatcheri)

The Patagonian Silverside belongs to the family Atherinopsidae (Neotropical Silversides) which is widespread in North and South America. It is a member of the genus Odontesthes which contains around 46 species. Odontesthes are restricted to South America and occur in a variety of freshwater and marine habitats from southern Brazil around Tierra del Fuego and then north to Peru. The Patagonian Silverside
Photo courtesy of Cecilia Conte-Grand is endemic to lakes and rivers of southern Argentina and Chile. In Argentina they occur from the Rio Colorado south to the Rio Deseado. In Chile they occur in Pacific flowing rivers that extend into Argentina in the continental Chiloé and Aysén regions. They have elongated bodies suited to life in the pelagic zone of lakes. As their common names implies they are largely silvery in coloration with a more intense silvery iridescent midlateral strip. They are an important fish in the region, both for a forage fish for larger sportfishes such as trouts and perch as well as for human consumption.

Trout Perch

Photo courtesy of Daniel Ruzzante Creole Perch (Percichthys trucha)

The Trout Perch belongs to the family Percichthyidae which contains around 24 species which are found in freshwater habitats in Australia and southern South America. Within South America there are two genera (Percichthys and Percilia), each with two species. Trout Perch are endemic to Argentina and Chile. In Argentina they range from the Rio Colorado south to Tierra del Fuego. In Chile they are mostly found between the Rio Aconcagua to Rio Maullin (Puerto Montt) in Pacific drainages as well as in southern Atlantic drainages. Trout Perch are most abundant in lakes and reservoirs, but also occur in larger rivers. They are a deeper bodied fish shaped like a typical perch. They have large mouths and feed on a variety of invertebrates and fishes. They grow to a maximum size of about 45 cm and 1.2 kg. They are an important fish in the region, both as a sportfish and for human consumption.

Patagonian Catfish

Bagres de Torrente (Hatcheria macraei)

The Patagonian Catfish belongs to a monotypic genus within the catfish family Trichomycteridae (Pencil or Parasitic Catfishes). The family Trichomycteridae is widespread within Central and South America with over 230 species. About half of these species are presently classified in the genus Trichomycterus (Pencil Catfishes), which is closely related to Hatcheria. Patagonian Catfish are endemic to Argentina and Chile. In Argentina they range from the Rio Colorado south to the Rio Deseado. In Chile they occur in Pacific flowing rivers that extend into Argentina in the continental Chiloé and Aysén regions. Patagonian Catfish are largely benthic and primarily occur in smaller fast flowing streams and rivers. They have elongated pencil like bodies with whiskers around their mouths to assist in finding food. They grow to a maximum size of about 20 cm.

Ruzzante D. E., S. J. Walde, V. E. Cussac, M. L. Dalebout, J. Seibert, S. Ortubay, E. Habit. 2006. Phylogeography of the Percichthyidae in Patagonia: roles of orogeny, glaciation, and volcanism. Molecular Ecology, 15:2949-2968.

Buria L., S. J. Walde, M Battini, P. J. Macchi, M. Alonso, D. E. Ruzzante, V. E. Cussac. 2006. Movement of a South American perch (Percichthys trucha) in a montane Patagonian lake during spawning and pre-spawning periods. Journal Fish Biology (in press).

Ruzzante D. E., S. J. Walde, V. E. Cussac, P. J. Macchi, M. Alonso, M. Battini. 2003. Trophic polymorphism in Pecichthys trucha (Pisces, Percichthyidae) in the Andes: phenotypic evidence for variation among lakes. Biological Journal of the Linnean Society, 78:497-515.

Logan M. S., S. J. Iverson, D. E. Ruzzante, S. J. Walde, P. Macchi, M. Alonso, V. E. Cussac. 2000. Long term diet differences between morphs in trophically polymorphic Percichthys trucha (Pisces: Percichthyidae) populations from the southern Andes. Biological Journal of the Linnean Society, 69:599-616.

Ruzzante D. E., S. J. Walde, V. E. Cussac, P. Macchi, M. Alonso. 1998. Trophic polymorphism, habitat and diet segregation within Percichthys trucha (Percichthyidae, Pisces) in the Andes. Biological Journal of the Linnean Society, 65:191-214.

Further Information:

http://www.costapatagonica.org.ar