Data from: Introgression threatens the survival of the critically endangered freshwater crayfish Cherax tenuimanus (Decapoda : Parastacidae) in the wild

Hybridization and genetic introgression following the introduction of
exotic species can pose a significant threat to the survival of
geographically restricted species. A remnant population of the critically
endangered freshwater crayfish Cherax tenuimanus in the upper reaches of
the Margaret River in southwestern Australia is under threat following the
introduction and spread of its congener Cherax cainii. Here, we examine
the extent of hybridization and introgression between the two species
using twelve polymorphic microsatellite loci. Our study reveals there are
three times more C. cainii than C. tenuimanus at our study site in the
upper reaches of the Margaret River. There is also evidence of
hybridization and introgression between C. tenuimanus and C. cainii at
this site, with F1, F2 and backcrossed individuals identified. While
interbreeding was confirmed in this study, our simulations suggest that
the levels of introgression are much lower than would be expected under
random mating, indicating partial reproductive barriers exist.
Nevertheless, it is apparent that hybridization and introgression with C.
cainii pose a serious threat to C. tenuimanus and their survival in the
wild will require active adaptive management and continued genetic
monitoring to evaluate management effectiveness.