Reconstructing the introduction history of an invasive fish predator in South Africa

Abstract

The Largemouth Bass (Micropterus salmoides) is a global invader with demonstrated ecological impacts on native fish communities. Introductions of fishes in freshwater ecosystems are often characterized as complex processes, yet an understanding of the nature of the introduction can inform management and conservation actions. Early in the twentieth century, two introductions of Largemouth Bass were made into South Africa for the establishment of a recreational fishery, and subsequent translocations have expanded their dis-Keywords Invasion reconstruction Á Microsatellite Á Freshwater fish Á Centrarchidae Á DIYABC Electronic supplementary material The online version of this article (

Biotic Interactions as Mediators of Biological Invasions: Insights from South Africa

“…In an assessment of the parasitism of largemouth bass for example, Truter et al (2017) documented lower parasite abundance and richness in South Africa in comparison with native range populations. This may explain why this species managed to invade a wide range of habitats throughout southern Africa despite extremely low genetic diversity, resulting from a very limited number of propagules introduced into South Africa in the late 1920s (Hargrove et al 2017). Similar mechanisms might be responsible for the success of rainbow trout, Onchorhynchus mykiss, and brown trout, Salmo trutta, for which there are no records of co-introduced parasites (see Weyl et al 2020, Sect.…”

The ghost of introduction past: Spatial and temporal variability in the genetic diversity of invasive smallmouth bass

“…These specific sampling sites, however, often display much lower levels of genetic variability when compared to rivers, as suggested by our results (localities BU and MP in the invasive range). Similarly, a recent study reconstructing the invasion history of the largemouth bass, Micropterus salmoides , identified extremely low levels of neutral genetic diversity within invasive populations in lentic environments with limited connectivity (Hargrove, Weyl, & Austin, 2017). Their results revealed that all lentic populations had allele frequencies dominated by a single allele, but that a population sampled from Kowie Weir, located at the end of a 580 km 2 catchment, was more diverse, suggesting multiple introduction events or hybridization between co‐occurring Micropterus species (Hargrove et al., 2017).…”

“…However, sampling problems such as the number of native versus invasive populations sampled and the number of individuals sampled per population may hinder the accuracy of the molecular markers to identify the source population . To date, however, no study has looked at the effect that identified extremely low levels of neutral genetic diversity within invasive populations in lentic environments with limited connectivity (Hargrove, Weyl, & Austin, 2017). Their results revealed that all lentic populations had allele frequencies dominated by a single allele, but that a population sampled from Kowie Weir, located at the end of a 580 km 2 catchment, was more diverse, suggesting multiple introduction events or hybridization between co-occurring Micropterus species (Hargrove et al, 2017).…”

“…To date, however, no study has looked at the effect that identified extremely low levels of neutral genetic diversity within invasive populations in lentic environments with limited connectivity (Hargrove, Weyl, & Austin, 2017). Their results revealed that all lentic populations had allele frequencies dominated by a single allele, but that a population sampled from Kowie Weir, located at the end of a 580 km 2 catchment, was more diverse, suggesting multiple introduction events or hybridization between co-occurring Micropterus species (Hargrove et al, 2017). Thus, choice of sampling locality and, in particular, the degree of isolation are important considerations when assessing the demographic or invasion history of a species.…”

Global Patterns in the Motivations and Behaviors of Tournament Anglers Targeting Bedding Bass

“…In southern Africa, for example, populations of Largemouth Bass were first established in the late 1920s (Harrison ; Hargrove et al. ) and became widespread by the 1930s (Ellender and Weyl ); competitive fishing events are now routinely held in Botswana, Namibia, Mozambique, South Africa, and Zimbabwe (Hargrove et al. ).…”