Freshwater fishes of Patagonia: conservation and fisheries

Abstract

The absence of much literature on the Patagonian fish fauna in comparison with that of the neotropics, has previously been blamed on its poor species diversity. Knowledge of the fishes of Patagonia, however, rose sharply at the beginning of the present century, allowing for an understanding of the complex biogeographical history that has led to the present diversity and distribution patterns. There are several new and potential threats to biodiversity and conservation of Patagonian fishes, such as the introduction of exotic species, damming, climate change and changes geared to safeguard economic interests, often acting synergistically. A great amount of new information is now available and the aim of the present review is to articulate this knowledge in a comprehensive way in order to aid in the development of tools to face the increasing challenges posed by environmental change and human activity. Knowledge about fishes of Patagonia has grown at the same time as human actions, and presence.

Back to the future? Late Holocene marine food web structure in a warm climatic phase as a predictor of trophodynamics in a warmer South‐Western Atlantic Ocean

“…In any case, common galaxias ( Galaxias maculatus [Jenyns, 1842]) dominated the freshwater fish fauna existing 1,278–1,013 cal years BP at Tierra de Fuego, as salmonids had not been introduced yet (Cussac et al, ). Common galaxias migrate to estuaries to spawn and Bahía Cambaceres Interior had a strong estuarine influence 1,278–1,013 cal years BP (Zangrando, Ponce, et al, ), thus suggesting the existence of a higher connectivity between freshwater and marine ecosystems in the Beagle Channel 1,278–1,013 cal years BP.…”

“…Ancient cormorant from other archaeological sites in the Beagle Channel had stable isotope ratios more consistent with a marine diet (Kochi et al, ), but the ancient cormorant from Lanashuaia II may have relied largely on migratory common galaxias spawning in the area (Casaux et al, ). However, the abundance of common galaxias has declined as a result of the introduction of salmonids and the fish community of the lower reaches of rivers and estuaries is currently dominated by exotic species (Cussac et al, ), too large to be exploited successfully by cormorants (Casaux et al, ). Thus, the above reported shift in the isotopic niche of cormorants might be explained by the decline of common galaxias.…”

Why does freshwater fish species richness differ between Pacific and Atlantic drainages of the Americas?

“…Note that species densities tend to be greater in Pacific than Atlantic drainages >50 °N, perhaps reflecting post‐glacial recolonization from the Beringian refuge (Lindsey & McPhail, ): the greater richness in glaciated Pacific NA over other Pacific locations (Figure b) is consistent with this conclusion. Recolonization is also favoured by an increased incidence of diadromous species at high latitudes (Cussac et al., ; McDowall, ). Two biotic provinces are recognized in Chile (Dyer, ).…”

Using a Population Model to Inform the Management of River Flows and Invasive Carp (Cyprinus carpio)

“…Carp (Cyprinus carpio L.) is a highly invasive alien species that occurs widely throughout the world (Lever 1996;Crichigno et al 2016) and has invaded south-eastern Australia over the past 50 years (Koehn et al 2000). With biological attributes (e.g., high fecundities and rates of movement) that allow their populations to expand rapidly (Ricciardi and Rasmussen 1998;Koehn 2004), this species has become widespread and highly abundant (Koehn et al 2000).…”