The Arapaima Fish

            The introduction and establishment of arapaima (Arapaima gigas) in southeastern Peru and northwestern Bolivia is an example of a fish species that appears to be increasingly common and widespread in non-native portions of its range, but whose populations are on the decline within its native range. The arapaima is overfished and considered threatened throughout its native range in the Central Amazon. We gathered and examined data on the distribution of fish and wildlife in the Takana II Indigenous Territory in Bolivia, near the arapaima’s reported initial invasion zone in Peru. Results confirmed the presence of arapaima in several water bodies where local people have also reported a strong decline in native fish populations. Further south in the Takana I Indigenous Territory, monitoring of fisheries by local communities (2002-2008), including observations on arapaima catches, indicate that until 2008 arapaima had not been reported in the area. However in 2009, there were reports of arapaima in the Undumo stream. Our results demonstrate that since the first presence of arapaima in Bolivia at the beginning of the 1980s, it has steadily expanded its distribution. We propose actions to mitigate this situation by managing and controlling populations of this invasive and endangered species, as well as improving income for indigenous communities.

        Arapaima [Arapaima gigas (Schinz, 1822)], known as paiche in Bolivia and Peru and as pirarucú in Brazil, is one of the most emblematic species of the Amazon and the focus of numerous studies (Migdalaski 1957; Hrbek et al. 2005; Castello et al. 2009). This giant fish is native to the Central Amazon where it has long been over-exploited by humans as a source of food (Figure 1) (Hrbek et al. 2007). The arapaima was introduced into lagoons in the Madre de Dios region of Peru for aquaculture and during the late 1970s these fish or their progeny escaped into nearby streams during flood events (Wust 2001; Farrel and Azurduy 2006). Local people report that the introduction of arapaima has caused serious environmental impacts. In northern Bolivia, it may be causing a reduction of native fish populations, including many fish of high commercial value