Scale, connectivity, and incentives in the introduction and management of non‐native species: the case of exotic salmonids in Patagonia

Abstract

Many introduced species have become established throughout large areas of the world, causing millions of dollars in damages. The introduction of such pest species is universally condemned, and science and management efforts are geared toward eradication, containment, or prevention of future infestations. Meanwhile, other organisms are actively traded around the world for consumption, as well as recreational and aesthetic purposes, providing examples of the conflict between human development and conservation. When dealing with such species, are there ways to balance the competing goals of economic production and protection of nature? How can science help to identify suitable compromises? We address these questions by analyzing three case studies dealing with exotic salmonids in Patagonia: trout aquaculture in shallow, fishless lakes; trout recreational fisheries; and marine net‐pen salmon aquaculture. We propose that three interrelated properties of these case studies (scale, connectivity, and incentives for conservation) determine our ability to identify and promote situations that balance production and the integrity of nature.

High incidence of invertebrate‐chemoautotroph symbioses in benthic communities of the New Zealand fjords

“…These regions similarly experience very high precipitation and levels of sedimentation (Silva and Prego 2002;Nuwer and Keil 2005;Sepú lveda et al 2009), although to the best of our knowledge similar studies of OM flux through infaunal communities have not been conducted to date. Such knowledge would be particularly relevant given the exploitation of higher trophic level species in these regions that are likely supported by such macroinfaunal communities, and potential changes to sediment chemistry caused by the dramatic increase in aquaculture developments in the Chilean fjords (Pascual et al 2009). …”

Escaped farmed salmon and trout in Chile: incidence, impacts, and the need for an ecosystem view

“…Among freshwater introductions, salmonids are considered to be among the most pervasive exotic species in the world (Pascual et al 2009). In Chile, the environmental concerns from salmonid escapes have focused on shortterm predatory effects upon native fish, long-term effects linked to the probability of farmed salmon establishing self-sustainable populations, and disease and pathogen transfer (Young et al 2010, Arismendi et al 2012, Niklitschek et al 2013).…”

Dealing with non-native species: what makes the difference in South America?

“…Therefore, the case of South America might be considered as a shifting baseline in the form of generational amnesia, where knowledge extinction occurs because younger generations are not aware of past biological conditions (Papworth et al 2009). Moreover, non-native species are often much valued and protected by local people, in part, because they represent an income (Pascual et al 2009;Lambertucci and Speziale 2011). They are hunted or fished, restaurants advertise them as traditional dishes, and souvenir shops sell souvenirs with their likeness represented (Fig.…”