Population structure and management of invasive cats on an Australian Island

Abstract

Invasive predators have a major impact on endemic island species; therefore, information about invasion dynamics are essential for implementing successful control measures. The introduction of feral cats onto Dirk Hartog Island, Western Australia, has had devastating effects, with presumably 10 of 13 native terrestrial mammal species being lost because of predation. Detailed records of historical introduction events were lacking; therefore, we analyzed genetic variation of the current population to gain information about past invasion dynamics and current gene‐flow patterns. We analyzed the genetic structure and diversity of feral cats on the island and 2 mainland populations (Peron Peninsula and Steep Point). Analysis of mitochondrial DNA (ND5 and ND6) showed 2 primary haplotypes that we attribute to 2 main introduction events. Pairwise G″ST values indicated high connectivity on the island but some isolation to the mainland populations. Mitochondrial and nuclear data showed no evidence for genetic differentiation of island and mainland populations; however, kinship analyses rejected evidence for on‐going immigration of members of the current cat populations. Overall, our data suggested that gene flow following the main introduction events ceased some years ago. Because current island populations appear to be reproductively isolated from mainland populations, a sufficiently large‐scale eradication measure might successfully diminish feral cat populations long‐term. © 2014 The Wildlife Society.

Feral Cat Globetrotters: genetic traces of historical human‐mediated dispersal

“…; Koch et al. ). Microsatellite analysis was conducted with all samples except Sulawesi, because samples did not yield sufficient nuclear DNA for adequate genetic analysis.…”

“…A total of 1800 base pairs (bp) of the mitochondrial ND5 and ND6 region were sequenced using a Bio‐Rad C1000 Thermocycler using conditions as outlined in Koch et al. (). For microsatellite analysis, we genotyped at 12 microsatellite loci, which included a gender‐identifying sequence tagged site from the domestic cat Y chromosome SRY gene (Butler et al.…”

“…Cocos (Keeling) Island is hereafter referred to as Cocos Island. Trapping, collection of tissue, hair, and blood samples as well as genomic and mitochondrial DNA isolation were conducted as described in Koch et al (2014). A total of 1800 base pairs (bp) of the mitochondrial ND5 and ND6 region were sequenced using a Bio-Rad C1000 Thermocycler using conditions as outlined in Koch et al (2014).…”

“…Trapping, collection of tissue, hair, and blood samples as well as genomic and mitochondrial DNA isolation were conducted as described in Koch et al (2014). A total of 1800 base pairs (bp) of the mitochondrial ND5 and ND6 region were sequenced using a Bio-Rad C1000 Thermocycler using conditions as outlined in Koch et al (2014). For microsatellite analysis, we genotyped at 12 microsatellite loci, which included a gender-identifying sequence tagged site from the domestic cat Y chromosome SRY gene (Butler et al 2002;Menotti-Raymond et al 2005;Koch et al 2014).…”

“…A total of 1800 base pairs (bp) of the mitochondrial ND5 and ND6 region were sequenced using a Bio-Rad C1000 Thermocycler using conditions as outlined in Koch et al (2014). For microsatellite analysis, we genotyped at 12 microsatellite loci, which included a gender-identifying sequence tagged site from the domestic cat Y chromosome SRY gene (Butler et al 2002;Menotti-Raymond et al 2005;Koch et al 2014). Microsatellite analysis was conducted with all samples except Sulawesi, because samples did not yield sufficient nuclear DNA for adequate genetic analysis.…”