Data from: Losing cichlid fish biodiversity: genetic and morphological homogenization of tilapia following colonization by introduced species
Shechonge, Asilatu, University of Dar es Salaam, University of Bristol
Ngatunga, Benjamin P., University of Dar es Salaam
Tamatamah, Rashid, University of Dar es Salaam
Bradbeer, Stephanie J., University of Bristol
Harrington, Jack, University of Bristol
Ford, Antonia G.P.
Turner, George F., Bangor University
Genner, Martin J., University of Bristol
Ford, Antonia G. P., University of Roehampton
Published Jun 27, 2019 on Dryad.
Cite this dataset
Shechonge, Asilatu et al. (2019). Data from: Losing cichlid fish biodiversity: genetic and morphological homogenization of tilapia following colonization by introduced species [Dataset]. Dryad. https://doi.org/10.5061/dryad.38c4h63
Among the many negative impacts of invasive species, hybridization with indigenous species has increasingly become recognized as a major issue. However, few studies have characterized the phenotypic outcomes of hybridization following biological invasions. Here we investigate the genetic and morphological consequences of stocking invasive tilapia species in two water bodies in central Tanzania. We sampled individuals from Mindu Reservoir on the Ruvu river system, and at Kidatu on the Great Ruaha-Rufiji river system. We screened individuals at 16 microsatellite loci, and quantified morphology using geometric morphometrics and linear measurements. In both the Mindu and Kidatu systems, we identified evidence of hybridization between indigenous Wami tilapia (Oreochromis urolepis) and the introduced Nile tilapia (Oreochromis niloticus) or blue-spotted tilapia (Oreochromis leucostictus). At both sites, purebred individuals could largely be separated using geometric morphometric variables, with hybrids occupying a broad morphospace among the parental species. Our data demonstrate that the gene pools and phenotypic identity of the indigenous O. urolepis have been severely impacted by the stocking of the invasive species. Given the lack of evidence for clear commercial benefits from stocking invasive tilapia species in waters already populated by indigenous congenerics, we suggest further spread of introduced species should be undertaken with considerable caution.
Microsatellite data, Convert format, for focal sites and reference samples
Landmark coordinates, tps file
Linear measurements. Included are species assignments based on the genetic data (Structure output).