Differential invasion success of salmonids in southern Chile: patterns and hypotheses

Evaluating taxonomic homogenization of freshwater fish assemblages in Chile

“…We designated each area of endemism as one biotic unit: Titicaca (U1, 18°S-23°S), Atacama (U2, 18°S-22°S), Central (U3, 28°S-33°S), South-Central (U4, 35°S-39°S), and South (U5, 39°S-42°S). Several studies have documented the presence of non-native taxa, especially salmonids, in both U5 and Patagonia province (e.g., Soto et al 2006Habit et al 2010;Arismendi et al 2012;Arismendi et al 2014). Although Patagonia has not been described as an area of endemism, we included it as the sixth biotic unit of our study (U6, 42°S-55°S).…”

“…So-called naturalized species with narrow geographic distributions are likely to contribute to TD within and between biotic units rather than TH, which is seemingly driven by invasive species widely distributed across watersheds. All three dimensions-the invader, biotic interactions, and human-have been recognized as crucial to understand the complexity of invasions (Arismendi et al 2014), even though their importance are still the subject of much debate (Hayes and Barry 2008;Martin et al 2009;Sol et al 2012). Parallel patterns and processes of invasions among Chile's watersheds and regions around the world might help evaluate the importance of such dimensions.…”

“…Native and alien (non-native) taxa have been suffixed with "N" and "A," respectively Introduction of salmonids in Chile has occurred since the late 1800s motivated by the establishment of recreational fisheries, with stocking efforts as common practice since 1960 until the present (Basulto 2003;Arismendi and Nahuelhual 2007;Arismendi et al 2014). During the last three decades, both recreational fishing and salmon farming have experienced an explosive growth, especially in the southern portion of the country spanning South (U5) and Patagonia (U6) units (Basulto 2003;Gajardo and Laikre 2003;Arismendi et al 2009, Buschmann et al 2009Arismendi et al 2014). However, both Rainbow Trout and Brown Trout are also abundant at northern latitudes as far as Atacama (U2), which likely explains the highest estimates of TH found in our study when we compared U2 and U5.…”

“…However, both Rainbow Trout and Brown Trout are also abundant at northern latitudes as far as Atacama (U2), which likely explains the highest estimates of TH found in our study when we compared U2 and U5. Collectively, propagule pressure, species traits (e.g., demography, migratory life history, phenotypic plasticity, and physiological tolerance), and low environmental resistance have concomitantly contributed to the current dominance of free-living salmonids and their invasion success in Chile (Soto et al 2006;Arismendi et al 2014). Yet, environmental and landscape attributes such as temperature, connectivity between lakes, and hydrological position have been documented to restrict the viability and current abundance of both native fishes and salmonids in Patagonia (U6: Soto et al 2006;Habit et al 2012;Correa and Hendry 2012).…”

Collaboration between Atlantic and Pacific salmon biologists to enhance recovery of endangered salmon in North America

“…They bring the power of these models to the toolbox of fisheries managers. Arismendi et al (2014) review the invasion of Atlantic and Pacific salmon in Chile and provide recommendations on control efforts based on patterns of invasion and the biology of these species. Finally, Jane et al (2014) contribute a unique paper that spans biology and archaeology to provide a multidisciplinary context to infer historical abundance and geographic distribution of North American salmon populations.…”