The invasion of Patagonia by Chinook salmon (Oncorhynchus tshawytscha): inferences from mitochondrial DNA patterns

  title={The invasion of Patagonia by Chinook salmon (Oncorhynchus tshawytscha): inferences from mitochondrial DNA patterns},
  author={Carla Riva Rossi and Miguel Pascual and E. Aedo Marchant and N{\'e}stor G. Basso and Javier Ernesto Ciancio and B. Mezga and Daniel Alfredo Fern{\'a}ndez and B. Ernst-Elizalde},
The Chinook salmon Oncorhynchus tshawytscha, which was introduced deliberately in Chile four decades ago for sport fishing and aquaculture, represents a rare example of a successful translocation of an anadromous Pacific salmon into the southern Hemisphere, offering a unique opportunity to examine the role of introduction history and genetic variability in invasion success. We used historical information and mitochondrial displacement loop sequences (D-loop) from seven colonized sites in Chile… 

Disentangling the contributions of ocean ranching and net-pen aquaculture in the successful establishment of Chinook salmon in a Patagonian basin

The results revealed that Chinook salmon established in the Futaleufú River have high levels of within-population genetic diversity compared with populations from across the native range and subsequent admixture and hybridization among these multiple independent source stocks is likely responsible for the high level of standing genetic variation.

Young-of-the-year Coho Salmon Oncorhynchus kisutch recruit in fresh waters of remote Patagonian fjords in southern Chile (51°S)

This work assesses the natal origin of young-of-the-year Coho Salmon collected from estuaries and lakes associated with remote Patagonian fjords by examining their otolith microchemical composition and provides the first ever evidence of recruitment and probable establishment of self-sustaining Coho salmon population in Patagonia.

The invasion of an Atlantic Ocean river basin in Patagonia by Chinook salmon: new insights from SNPs

It is suggested that the successful invasion of the Caterina River in Patagonia by Chinook salmon was aided by pre-adaptations of some of the stocks used in the ocean ranching experiments to conditions in the new environment, rather than a post-colonization adaptation.

Temporal Genetic Variance and Propagule-Driven Genetic Structure Characterize Naturalized Rainbow Trout (Oncorhynchus mykiss) from a Patagonian Lake Impacted by Trout Farming

The results reinforce the notion that naturalized trout originated recently from a small yet genetically diverse source and that farm propagules might have played a significant role in the invasion of Rainbow Trout within a single lake with intensive trout farming and argue for proficient mitigation measures that include management of escapes and strategies to minimize unintentional releases from farm facilities.

Size structure, age, and diets of introduced Chinook salmon (Oncorhynchus tshawytscha) inhabiting the Palena River, Chilean Patagonia

Immature adults, with ages between 3+ and 4+, were collected from a small lake (Claro Solar), displayed a piscivorous diet mainly based on native Galaxid species, and all the adult salmon were devoid of food.

Genetic signals of artificial and natural dispersal linked to colonization of South America by non‐native Chinook salmon (Oncorhynchus tshawytscha)

These findings support a model of colonization in which high‐diversity artificial populations established first; some of these populations exhibited significant admixture resulting from propagule pressure, and low-diversity natural populations were likely subsequently founded from a reduced number of individuals.

Early development and diets of non‐native juvenile Chinook Salmon (Oncorhynchus tshawytscha) in an invaded river of Patagonia, southern South America

Diet analyses revealed a specialist feeding behaviour based on food pulses that included both aquatic and terrestrial insects; piscivory was not detected and juvenile salmon co‐occurred with native fishes suggesting a potential for interspecific interference.

Mixed-stock analyses of migratory, non-native Chinook salmon at sea and assignment to natal sites in fresh water at their introduced range in South America

Combined genetic evidence points strongly to homing among non-native Chinook salmon, whereby most adults return to breed to their natal river amid potentially long-distance migrations through the coast.



Chinook salmon invade southern South America

This is the first anadromous salmon species to have invaded such a large range in South America, and it raises many evolutionary, ecological, environmental and socioeconomic issues, with several discussed here.

The establishment of exotic Chinook salmon (Oncorhynchus tshawytscha) in Pacific rivers of Chubut, Patagonia, Argentina

The aim of this paper is to report the colonization process of three headwater rivers of two large trans-national Pacific river basins shared by Chile and Argentina, by exotic Chinook salmon

Natural Colonization and Establishment of a Chinook Salmon, Oncorhynchus tshawytscha, Population in the Santa Cruz River, an Atlantic Basin of Patagonia

SynopsisWe report the finding of an established population of exotic Chinook salmon spawning in headwaters of the Santa Cruz River system (Argentina), the first for this species in an Atlantic basin

Origin and genetic structure of chinook salmon, Oncorhynchus tshawytscha, transplanted from California to New Zealand: allozyme and mtDNA evidence

Chinook salmon. Onco­ rhynchus tshawytscha, transplanted from the Sacramento River. California, to the Waitaki River catchment ofNew Zealand at the turn ofthe century rap­ idly colonized many South

Colonization of the Southern Patagonia Ocean by Exotic Chinook Salmon

Abstract:  Anadromous salmonids have been particularly successful at establishing wild populations in southern Patagonia, in contrast to their limited success elsewhere outside their native ranges.

Chinook salmon (Oncorhynchus tshawytscha, Walbaum 1792) in the Beagle Channel, Tierra del Fuego: the onset of an invasion

The results provide support to the idea that, in practice, no district of Patagonia is sheltered from the colonization by invasive anadromous Salmonids.

Evolution of chinook salmon (Oncorhynchus tshawytscha) populations in New Zealand: pattern, rate, and process

It is suggested that in addition to genetic divergence resulting from random founder effects, divergence may also arise during the very early stages of colonization when the original colonists are a non-random, pre-adapted subset of the source population.

Contrasting patterns in genetic diversity following multiple invasions of fresh and brackish waters

The results confirm that biological invasions need not result in diminished genetic diversity, particularly if multiple source populations, each with distinctive genetic composition, contribute to the founding populations.

Mitochondrial Variation and Biogeographic History of Chinook Salmon

Nested clade analysis suggests northward expansion from this area during the late Pleistocene, a hypothesis that is further supported by evidence of demographic growth and population expansion in the northern portion of the species' range.

Winning the invasion roulette: escapes from fish farms increase admixture and facilitate establishment of non-native rainbow trout

It is suggested that non‐native salmonids introduced into the Southern Hemisphere could benefit from admixture because local adaptations may not have yet developed, and there may be initially little fitness loss resulting from outbreeding depression.